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Sample records for vo2max running velocity

  1. Peak treadmill running velocity during the VO2 max test predicts running performance.

    Science.gov (United States)

    Noakes, T D; Myburgh, K H; Schall, R

    1990-01-01

    Twenty specialist marathon runners and 23 specialist ultra-marathon runners underwent maximal exercise testing to determine the relative value of maximum oxygen consumption (VO2max), peak treadmill running velocity, running velocity at the lactate turnpoint, VO2 at 16 km h-1, % VO2max at 16 km h-1, and running time in other races, for predicting performance in races of 10-90 km. Race time at 10 or 21.1 km was the best predictor of performance at 42.2 km in specialist marathon runners and at 42.2 and 90 km in specialist ultra-marathon runners (r = 0.91-0.97). Peak treadmill running velocity was the best laboratory-measured predictor of performance (r = -0.88(-)-0.94) at all distances in ultra-marathon specialists and at all distances except 42.2 km in marathon specialists. Other predictive variables were running velocity at the lactate turnpoint (r = -0.80(-)-0.92); % VO2max at 16 km h-1 (r = 0.76-0.90) and VO2max (r = 0.55(-)-0.86). Peak blood lactate concentrations (r = 0.68-0.71) and VO2 at 16 km h-1 (r = 0.10-0.61) were less good predictors. These data indicate: (i) that in groups of trained long distance runners, the physiological factors that determine success in races of 10-90 km are the same; thus there may not be variables that predict success uniquely in either 10 km, marathon or ultra-marathon runners, and (ii) that peak treadmill running velocity is at least as good a predictor of running performance as is the lactate turnpoint. Factors that determine the peak treadmill running velocity are not known but are not likely to be related to maximum rates of muscle oxygen utilization.

  2. Interval training at 95% and 100% of the velocity at VO2 max: effects on aerobic physiological indexes and running performance.

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    Denadai, Benedito S; Ortiz, Marcelo J; Greco, Camila C; de Mello, Marco T

    2006-12-01

    The objective of this study was to analyze the effect of two different high-intensity interval training (HIT) programs on selected aerobic physiological indices and 1500 and 5000 m running performance in well-trained runners. The following tests were completed (n=17): (i) incremental treadmill test to determine maximal oxygen uptake (VO2 max), running velocity associated with VO2 max (vVO2 max), and the velocity corresponding to 3.5 mmol/L of blood lactate concentration (vOBLA); (ii) submaximal constant-intensity test to determine running economy (RE); and (iii) 1500 and 5000 m time trials on a 400 m track. Runners were then randomized into 95% vVO2 max or 100% vVO2 max groups, and undertook a 4 week training program consisting of 2 HIT sessions (performed at 95% or 100% vVO2 max, respectively) and 4 submaximal run sessions per week. Runners were retested on all parameters at the completion of the training program. The VO2 max values were not different after training for both groups. There was a significant increase in post-training vVO2 max, RE, and 1500 m running performance in the 100% vVO2 max group. The vOBLA and 5000 m running performance were significantly higher after the training period for both groups. We conclude that vOBLA and 5000 m running performance can be significantly improved in well-trained runners using a 4 week training program consisting of 2 HIT sessions (performed at 95% or 100% vVO2 max) and 4 submaximal run sessions per week. However, the improvement in vVO2 max, RE, and 1500 m running performance seems to be dependent on the HIT program at 100% vVO2 max.

  3. Estimated VO2max and its corresponding velocity predict performance of amateur runners

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    Bruno Ribeiro Ramalho Oliveira

    2012-03-01

    Full Text Available In recent years, there has been a substantial increase in the number of runners, with a proportional increase in their involvement in amateur street competition. Identification of the determinants of performance in this population appears necessary for optimization of time devoted to training. The objective of this study was to ascertain the association between estimated maximal oxygen uptake (VO2max, critical velocity (CV and VO2max velocity (VVO2max and athletic performance in the 3.6 km (uphill and 10 and 21.1 km (flatland events. Twelve amateur runners (nine male, mean age 36 ± 5 years underwent five tests: 1 and 5 km race on level ground, 3.6 km race with slope (≈8%, and indirect VO2max measurement. CV was determined from the linear relationship between distance and run time on the first two tests. The subjects then took part in two official 10 km and 21.1 km (half marathon races. VVO2max was calculated from the VO2max through a metabolic equation. VO2max showed the best association with running performance in the 10 and 21.1 km events. For the uphill race, VVO2max showed a better association. Overall, the variable with the highest average association was VO2max (0.91±0.07, followed by VVO2max (0.90±0.04 and VC (0.87±0.06. This study showed strong associations between physiological variables established by low-cost, user-friendly indirect methods and running performance in the 10 and 21.1 km (flatland and 3.6 km (uphill running events.

  4. Effect of protocol on determination of velocity at VO2 max and on its time to exhaustion.

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    Billat, V L; Hill, D W; Pinoteau, J; Petit, B; Koralsztein, J P

    1996-01-01

    The velocity associated with the achievement of VO2 max during an incremental treadmill test (v VO2 max) has been reported to be an indicator of performance in middle distance running events. Previous study has shown the reproducibility of the time to exhaustion (time limit: tlim) at v VO2 max performed by well-trained males in the same condition at one week of interval (Billat et al., 1994b). It is essential in studies involving tlim at v VO2 max that the v VO2 max be precisely determined, or else the measured tlim will be meaningless. The purpose of this study was to examine the influence of the stage duration and velocity incrementation on the velocity at VO2 max and, consequently, on the two times to exhaustion (tlim) associated with the two v VO2 max generated by the two protocols. v VO2 max was determined in 15 trained male endurance athletes as the lowest speed at which VO2 max was attained in speed-incremented 0%-slope treadmill tests. For one test, increments were 1.0 km.h-1 and stages were 2 min in duration; for the other test, increments were 0.5 km.h-1 and stages were 1 min in duration. Results of paired means t-tests revealed no difference in v VO2 max obtained using the two protocols. v VO2 max was 20.7 +/- 1.0 km.h-1 with the 1.0 km.h-1 x 2 min protocol and 20.8 +/- 0.9 km.h-1 with the 0.5 km.h-1 x 1 min protocol. In addition, VO2, VCO2, VE, VE/VO2 and respiratory exchange ratio at the submaximal intensities that were common to both protocols (e.g., 17.0 km.h-1, 18.0 km.h-1, 19.0 km.h-1, 20.0 km.h-1) did not differ. Times to exhaustion at the two v VO2 max demonstrated a high degree of inter-individual variability (coefficients of variation were 35% and 45%) but did not differ (345 +/- 120 s versus 373 +/- 169 s). These results demonstrated that small changes in protocol have no significant impact on the value of v VO2 max and in consequence on tlim v VO2 max.

  5. Time limit and time at VO2max' during a continuous and an intermittent run.

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    Demarie, S; Koralsztein, J P; Billat, V

    2000-06-01

    The purpose of this study was to verify, by track field tests, whether sub-elite runners (n=15) could (i) reach their VO2max while running at v50%delta, i.e. midway between the speed associated with lactate threshold (vLAT) and that associated with maximal aerobic power (vVO2max), and (ii) if an intermittent exercise provokes a maximal and/or supra maximal oxygen consumption longer than a continuous one. Within three days, subjects underwent a multistage incremental test during which their vVO2max and vLAT were determined; they then performed two additional testing sessions, where continuous and intermittent running exercises at v50%delta were performed up to exhaustion. Subject's gas exchange and heart rate were continuously recorded by means of a telemetric apparatus. Blood samples were taken from fingertip and analysed for blood lactate concentration. In the continuous and the intermittent tests peak VO2 exceeded VO2max values, as determined during the incremental test. However in the intermittent exercise, peak VO2, time to exhaustion and time at VO2max reached significantly higher values, while blood lactate accumulation showed significantly lower values than in the continuous one. The v50%delta is sufficient to stimulate VO2max in both intermittent and continuous running. The intermittent exercise results better than the continuous one in increasing maximal aerobic power, allowing longer time at VO2max and obtaining higher peak VO2 with lower lactate accumulation.

  6. The influence of exercise duration at VO2 max on the off-transient pulmonary oxygen uptake phase during high intensity running activity.

    Science.gov (United States)

    Billat, V L; Hamard, L; Koralsztein, J P

    2002-12-01

    The purpose of this study was to examine the influence of time run at maximal oxygen uptake (VO2 max) on the off-transient pulmonary oxygen uptake phase after supra-lactate threshold runs. We hypothesised: 1) that among the velocities eliciting VO2 max there is a velocity threshold from which there is a slow component in the VO2-off transient, and 2) that at this velocity the longer the duration of this time at VO2 max (associated with an accumulated oxygen kinetics since VO2 can not overlap VO2 max), the longer is the off-transient phase of oxygen uptake kinetics. Nine long-distance runners performed five maximal tests on a synthetic track (400 m) while breathing through the COSMED K4b2 portable, telemetric metabolic analyser: i) an incremental test which determined VO2 max, the minimal velocity associated with VO2 max (vVO2 max) and the velocity at the lactate threshold (vLT), ii) and in a random order, four supra-lactate threshold runs performed until exhaustion at vLT + 25, 50, 75 and 100% of the difference between vLT and vVO2 max (vdelta25, vdelta50, vdelta75, vdelta100). At vdelta25, vdelta50 (= 91.0 +/- 0.9% vVO2 max) and vdelta75, an asymmetry was found between the VO2 on (double exponential) and off-transient (mono exponential) phases. Only at vdelta75 there was at positive relationship between the time run at VO2 max (%tlimtot) and the VO2 recovery time constant (Z = 1.8, P = 0.05). In conclusion, this study showed that among the velocities eliciting VO2 max, vdelta75 is the velocity at which the longer the duration of the time at VO2 max, the longer is the off-transient phase of oxygen uptake kinetics. It may be possible that at vdelta50 there is not an accumulated oxygen deficit during the plateau of VO2 at VO2 max and that the duration of the time at VO2 max during the exhaustive runs at vdelta100, could be too short to induce an accumulating oxygen deficit affecting the oxygen recovery.

  7. Percent utilization of VO2 max at 5-km competition velocity does not determine time performance at 5 km among elite distance runners.

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    Støa, Eva Maria; Støren, Øyvind; Enoksen, Eystein; Ingjer, Frank

    2010-05-01

    The present study investigated to what extent maximum oxygen uptake (VO2 max) and fractional utilization (%VO2 max) in 5-km competition speed correlate with 5-km performance times among elite long distance runners. Eight elite long distance runners with 5-km performance times of 15.10 minutes ( +/- 32 seconds) were tested for VO2 max during an incremental protocol and for %VO2 max during an 8-minute treadmill test at the velocity representing their 5-km seasonal best performance time. There was no correlation between fractional utilization and 5-km performance. The study showed no significant difference between VO2 max obtained during an incremental VO2 max test and %VO2 max when running for 8 minutes at the runner's individual 5-km competition speed. The 5-km time was related to the runner's VO2 max even in a homogenous high-level performance group. In conclusion, the present study found no relationship between fractional utilization and 5-km performance time. Training aiming to increase %VO2 max may thus be of little or no importance in performance enhancement for competitions lasting up to approximately 20 minutes.

  8. Time to Exhaustion at the VO2max Velocity in Swimming: A Review.

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    Fernandes, Ricardo J; Vilas-Boas, J Paulo

    2012-05-01

    The aim of this study was to present a review on the time to exhaustion at the minimum swimming velocity corresponding to maximal oxygen consumption (TLim-vVO2max). This parameter is critical both for the aerobic power and the lactate tolerance bioenergetical training intensity zones, being fundamental to characterize it, and to point out its main determinants. The few number of studies conducted in this topic observed that swimmers were able to maintain an exercise intensity corresponding to maximal aerobic power during 215 to 260 s (elite swimmers), 230 to 260 s (high level swimmers) and 310 to 325 s (low level swimmers), and no differences between genders were reported. TLim-vVO2max main bioenergetic and functional determinants were swimming economy and VO2 slow component (direct relationship), and vVO2max, velocity at anaerobic threshold and blood lactate production (inverse relationship); when more homogeneous groups of swimmers were analysed, the inverse correlation value between TLim-vVO2max and vVO2max was not so evident. In general, TLim-vVO2max was not related to VO2max. TLim-vVO2max seems also to be influenced by stroking parameters, with a direct relationship to stroke length and stroke index, and an inverse correlation with stroke rate. Assessing TLim-vVO2max, together with the anaerobic threshold and the biomechanical general parameters, will allow a larger spectrum of testing protocols application, helping to build more objective and efficient training programs.

  9. Is time limit at the minimum swimming velocity of VO2 max influenced by stroking parameters?

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    Fernandes, Ricardo J; Marinho, Daniel A; Barbosa, Tiago M; Vilas-Boas, J Paulo

    2006-08-01

    The aim of this study was to observe the relationship between time limit at the minimum velocity that elicits maximal oxygen consumption (TLim-v VO2 max) and stroke rate, stroke length, and stroke index. 13 men and 10 women, highly trained swimmers, performed an intermittent incremental test for v VO2 max assessment and an all-out swim to estimate TLim-v VO2 max. The mean +/- SD TLim-v VO2 max, v VO2 max, stroke rate, stroke length, and stroke index values were 233.36 +/- 53.92 sec., 1.40 +/- .06 meter/sec., 35.58 +/- 2.89 cycles/min., 2.39 +/- .22 meter/cycle, and 3.36 +/- .41 meter2/(cycle x sec.), respectively. The correlation between TLim-v VO2 max and stroke rate was -.51 (p VO2 max with stroke length (r = .52, p < .01) and stroke index (r = .45, p < .05). These results seem to suggest that technical skill is a key factor in typical efforts requiring prolonged aerobic power.

  10. Predicting maximal aerobic capacity (VO2max) from the critical velocity test in female collegiate rowers.

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    Kendall, Kristina L; Fukuda, David H; Smith, Abbie E; Cramer, Joel T; Stout, Jeffrey R

    2012-03-01

    The objective of this study was to examine the relationship between the critical velocity (CV) test and maximal oxygen consumption (VO2max) and develop a regression equation to predict VO2max based on the CV test in female collegiate rowers. Thirty-five female (mean ± SD; age, 19.38 ± 1.3 years; height, 170.27 ± 6.07 cm; body mass, 69.58 ± 0.3 1 kg) collegiate rowers performed 2 incremental VO2max tests to volitional exhaustion on a Concept II Model D rowing ergometer to determine VO2max. After a 72-hour rest period, each rower completed 4 time trials at varying distances for the determination of CV and anaerobic rowing capacity (ARC). A positive correlation was observed between CV and absolute VO2max (r = 0.775, p < 0.001) and ARC and absolute VO2max (r = 0.414, p = 0.040). Based on the significant correlation analysis, a linear regression equation was developed to predict the absolute VO2max from CV and ARC (absolute VO2max = 1.579[CV] + 0.008[ARC] - 3.838; standard error of the estimate [SEE] = 0.192 L·min(-1)). Cross validation analyses were performed using an independent sample of 10 rowers. There was no significant difference between the mean predicted VO2max (3.02 L·min(-1)) and the observed VO2max (3.10 L·min(-1)). The constant error, SEE and validity coefficient (r) were 0.076 L·min(-1), 0.144 L·min(-1), and 0.72, respectively. The total error value was 0.155 L·min(-1). The positive relationship between CV, ARC, and VO2max suggests that the CV test may be a practical alternative to measuring the maximal oxygen uptake in the absence of a metabolic cart. Additional studies are needed to validate the regression equation using a larger sample size and different populations (junior- and senior-level female rowers) and to determine the accuracy of the equation in tracking changes after a training intervention.

  11. A comparison of two different shuttle run tests for the estimation of VO2max.

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    Naughton, L M; Cooley, D; Kearney, V; Smith, S

    1996-06-01

    The aims of this experiment were twofold. The first was to determine whether there was a significant difference between two types of 20-m shuttle run test used to estimate VO2max, these being the Canadian version (CT) and the European versione (ET). The second aim was to determine which of the two tests best estimated direct VO2 measurement in our laboratory. To accomplish the first aim, 500 schoolchildren aged 12 to 16 years were randomly chosen from schools within Tasmania to undertake the two tests within seven days of each other. On the day of testing the children were assigned to one of the two tests and had no knowledge as to which test was being undertaken. Half of the children underwent the CT test first while the other half undertook the ET test first. Seven days after the first test was completed the appropriate second test was undertaken. The instructions to each child centred around the necessity to complete as many shuttles as possible staying in time with a pre-recorded signal. A relationship between the two sets of shuttle run data indicated that there was a significant correlation between the ET and CT, r = 0.834 (p test revealed that when the estimates of VO2max were compared however, there was a significant difference between the two tests (p VO2max at 34.9 +/- 0.45 ml.kg-1.min-1 whereas the CT estimated VO2max at 43.3 +/- 0.40 ml.kg-1.min-1. When this data was correlated, the co-efficient dropped to r = 0.761 which was still significant (p VO2max test (DM) which was conducted via standard open circuit spirometry using a Quinton Metabolic Cart (QMC). The highest correlation was DM:ET being r = 0.93 whereas DM:CT was r = 0.87, both being significant at p VO2max as 37.6 +/- 0.37 ml.kg-1.min-1 whereas ET underestimated DM and measured VO2max at 34.7 +/- 0.56 ml.kg-1.min-1. The CT (41.9 +/- 0.62 ml.kg-1.min-1) over estimated DM by 11.4% however, the difference here also being significant (p test or the other in the estimation of VO2max as the two

  12. Validation of a Ramp Running Protocol for Determination of the True VO2max in Mice

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    Ayachi, Mohamed; Niel, Romain; Momken, Iman; Billat, Véronique L.; Mille-Hamard, Laurence

    2016-01-01

    In the field of comparative physiology, it remains to be established whether the concept of VO2max is valid in the mouse and, if so, how this value can be accurately determined. In humans, VO2max is generally considered to correspond to the plateau observed when VO2 no longer rises with an increase in workload. In contrast, the concept of VO2peak tends to be used in murine studies. The objectives of the present study were to determine whether (i) a continuous ramp protocol yielded a higher VO2peak than a stepwise, incremental protocol, and (ii) the VO2peak measured in the ramp protocol corresponded to VO2max. The three protocols (based on intensity-controlled treadmill running until exhaustion with eight female FVB/N mice) were performed in random order: (a) an incremental protocol that begins at 10 m.min−1 speed and increases by 3 m.min−1 every 3 min. (b) a ramp protocol with slow acceleration (3 m.min−2), and (c) a ramp protocol with fast acceleration (12 m.min−2). Each protocol was performed with two slopes (0 and 25°). Hence, each mouse performed six exercise tests. We found that the value of VO2peak was protocol-dependent (p VO2max plateau was associated with the fulfillment of two secondary criteria (a blood lactate concentration >8 mmol.l−1 and a respiratory exchange ratio >1). The total duration of the 3 m.min−2 0° ramp protocol was shorter than that of the incremental protocol. Taken as a whole, our results suggest that VO2max in the mouse is best determined by applying a ramp exercise protocol with slow acceleration and no treadmill slope. PMID:27621709

  13. Elite cross-country skiers do not reach their running VO2max during roller ski skating.

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    Losnegard, T; Hallén, J

    2014-08-01

    Cross-country skiers' VO2max is often measured during treadmill running. However, VO2max during treadmill skiing with the diagonal stride technique is higher, whereas it is lower during double poling, another classical style technique. How these values compare to VO2max during ski skating in elite cross country skiers is not known. Therefore, this study compared VO2max during treadmill uphill running and treadmill roller ski skating. Twenty-two males (21±2 years, 182±6 cm, 77±7 kg, VO2max running; 72.4±4.4 mL·kg-1·min-1) elite cross-country skiers and biathlon athletes underwent testing in both running and roller ski skating before (May) and at the end (October) of the preseason training. From May to October VO2max increased during running (3.1±4.5%, P=0.003, Effect size; ES=0.44, small) but not during roller ski skating (1.8±5.6%, P=0.13, ES=0.24, small). In May the subjects' VO2max during running was 1.7±4.7% higher compared to during roller ski skating (P=0.08, ES=0.24, small) while in October this difference was 3.0±5.0 % (PVO2max during roller ski skating than during running and this relationship does not change during the pre-season training period.

  14. Relationship between velocity reached at VO2(max) and time-trial performances in elite Australian Rules footballers.

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    Lorenzen, Christian; Williams, Morgan D; Turk, Paul S; Meehan, Daniel L; Kolsky, Daniel J Cicioni

    2009-09-01

    Running velocity reached at maximal oxygen uptake (vVO2(max)) can be a useful measure to prescribe training intensity for aerobic conditioning. Obtaining it in the laboratory is often not practical, and average velocities from time trials are an attractive alternative. To date, the efficacies of such practices for team sport players are unknown. This study aimed to assess the relationship between vVO2(max) obtained in the laboratory against two time-trial estimates (1500 m and 3200 m). During the early preseason, elite Australian Rules football players (n = 23, 22.7 +/- 3.4 y, 187.7 +/- 8.2 cm, 75.5 +/- 9.2 kg) participated in a laboratory test on a motorized treadmill and two outdoor time trials. Based on average velocity the 1500-m time-trial performance (5.01 +/- 0.23 m x s(-1)) overestimated (0.36 m x s(-1), d = 1.75), whereas the 3200-m time trial (4.47 +/- 0.23 m x s(-1)) underestimated (0.17 m x s(-1), d = 0.83) the laboratory vVO2(max) (4.64 +/- 0.18 m x s(-1)). Despite these differences, both 1500-m and 3200-m time-trial performances correlated with the laboratory measure (r = -0.791; r = -0.793 respectively). Both subsequent linear regressions were of good fit and predicted the laboratory measure within +/- 0.12 m x s(-1). Estimates of vVO2(max) should not be used interchangeably, nor should they replace the laboratory measure. When laboratory testing is not accessible for team sports players, prescription of training intensity may be more accurately estimated from linear regression based on either 1500-m or 3200-m time-trial performance than from the corresponding average velocity.

  15. Very short (15s-15s) interval-training around the critical velocity allows middle-aged runners to maintain VO2 max for 14 minutes.

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    Billat, V L; Slawinksi, J; Bocquet, V; Chassaing, P; Demarle, A; Koralsztein, J P

    2001-04-01

    The purpose of this study was to compare the effectiveness of three very short interval training sessions (15-15 s of hard and easier runs) run at an average velocity equal to the critical velocity to elicit VO2 max for more than 10 minutes. We hypothesized that the interval with the smallest amplitude (defined as the ratio between the difference in velocity between the hard and the easy run divided by the average velocity and multiplied by 100) would be the most efficient to elicit VO2 max for the longer time. The subjects were middle-aged runners (52 +/- 5 yr, VO2 max of 52.1 +/- 6 mL x min(-1) x kg(-1), vVO2 max of 15.9 +/- 1.8 km x h(-1), critical velocity of 85.6 +/- 1.2% vVO2 max) who were used to long slow distance-training rather than interval training. They performed three interval-training (IT) sessions on a synthetic track (400 m) whilst breathing through the COSMED K4b2 portable metabolic analyser. These three IT sessions were: A) 90-80% vVO2 max (for hard bouts and active recovery periods, respectively), the amplitude= (90-80/85) 100=11%, B) 100-70% vVO2 max amplitude=35%, and C) 60 x 110% vVO2 max amplitude = 59%. Interval training A and B allowed the athlete to spend twice the time at VO2 max (14 min vs. 7 min) compared to interval training C. Moreover, at the end of interval training A and B the runners had a lower blood lactate than after the procedure C (9 vs. 11 mmol x l(-1)). In conclusion, short interval-training of 15s-15s at 90-80 and 100-70% of vVO2 max proved to be the most efficient in stimulating the oxygen consumption to its highest level in healthy middle-aged long-distance runners used to doing only long slow distance-training.

  16. Time to Exhaustion at the VO2max Velocity in Swimming: A Review

    OpenAIRE

    Fernandes, Ricardo J.; Vilas-Boas, J. Paulo

    2012-01-01

    The aim of this study was to present a review on the time to exhaustion at the minimum swimming velocity corresponding to maximal oxygen consumption (TLim-vVO2max). This parameter is critical both for the aerobic power and the lactate tolerance bioenergetical training intensity zones, being fundamental to characterize it, and to point out its main determinants. The few number of studies conducted in this topic observed that swimmers were able to maintain an exercise intensity corresponding to...

  17. Erythropoietin elevates VO2,max but not voluntary wheel running in mice.

    Science.gov (United States)

    Kolb, E M; Kelly, S A; Middleton, K M; Sermsakdi, L S; Chappell, M A; Garland, T

    2010-02-01

    Voluntary activity is a complex trait, comprising both behavioral (motivation, reward) and anatomical/physiological (ability) elements. In the present study, oxygen transport was investigated as a possible limitation to further increases in running by four replicate lines of mice that have been selectively bred for high voluntary wheel running and have reached an apparent selection limit. To increase oxygen transport capacity, erythrocyte density was elevated by the administration of an erythropoietin (EPO) analogue. Mice were given two EPO injections, two days apart, at one of two dose levels (100 or 300 microg kg(-1)). Hemoglobin concentration ([Hb]), maximal aerobic capacity during forced treadmill exercise (VO2,max) and voluntary wheel running were measured. [Hb] did not differ between high runner (HR) and non-selected control (C) lines without EPO treatment. Both doses of EPO significantly (PVO2,max by approximately 5% in both the HR and C lines, with no dosexline type interaction. However, wheel running (revolutions per day) did not increase with EPO treatment in either the HR or C lines, and in fact significantly decreased at the higher dose in both line types. These results suggest that neither [Hb] per se nor VO2,max is limiting voluntary wheel running in the HR lines. Moreover, we hypothesize that the decrease in wheel running at the higher dose of EPO may reflect direct action on the reward pathway of the brain.

  18. Individual versus Standardized Running Protocols in the Determination of VO2max.

    Science.gov (United States)

    Sperlich, Paula F; Holmberg, Hans-Christer; Reed, Jennifer L; Zinner, Christoph; Mester, Joachim; Sperlich, Billy

    2015-06-01

    The purpose of this study was to determine whether an individually designed incremental exercise protocol results in greater rates of oxygen uptake (VO2max) than standardized testing. Fourteen well-trained, male runners performed five incremental protocols in randomized order to measure their VO2max: i) an incremental test (INCS+I) with pre-defined increases in speed (2 min at 8.64 km·h(-1), then a rise of 1.44 km·h(-1) every 30 s up to 14.4 km·h(-1)) and thereafter inclination (0.5° every 30 s); ii) an incremental test (INCI) at constant speed (14.4 km·h(-1)) and increasing inclination (2° every 2 min from the initial 0°); iii) an incremental test (INCS) at constant inclination (0°) and increasing speed (0.5 km·h(-1) every 30 s from the initial 12.0 km·h(-1)); iv) a graded exercise protocol (GXP) at a 1° incline with increasing speed (initially 8.64 km·h(-1) + 1.44 km·h(-1) every 5 min); v) an individual exercise protocol (INDXP) in which the runner chose the inclination and speed. VO2max was lowest (-4.2%) during the GXP (p = 0.01; d = 0.06-0.61) compared to all other tests. The highest rating of perceived exertion, heart rate, ventilation and end-exercise blood lactate concentration were similar between the different protocols (p VO2max attained by employing an individual treadmill protocol does not differ from the values derived from various standardized incremental protocols. Key pointsThe mean maximum oxygen uptake during the GXP was lower than for all other tests.Differences in the maximum rate of oxygen uptake between the various protocols exhibited considerable inter-individual variation.From the current findings, it can be concluded that well trained athletes are able to perform an individually designed treadmill running protocol.

  19. Convergent Validity of the One-Mile Run and PACER VO2MAX Prediction Models in Middle School Students

    Directory of Open Access Journals (Sweden)

    Ryan D. Burns

    2014-02-01

    Full Text Available FITNESSGRAM uses an equating method to convert Progressive Aerobic Cardiovascular Endurance Run (PACER laps to One-mile run/walk (1MRW times to estimate aerobic fitness (VO2MAX in children. However, other prediction models can more directly estimate VO2MAX from PACER performance. The purpose of this study was to examine the convergent validity and relative accuracy between 1MRW and various PACER models for predicting VO2MAX in middle school students. Aerobic fitness was assessed on 134 students utilizing the 1MRW and PACER on separate testing days. Pearson correlations, Bland–Altman plots, kappa statistics, proportion of agreement, and prediction error were used to assess associations and agreement among models. Correlation coefficients were strong (r ≥ .80, p .40 and agreement > .90. The results support that PACER models contain convergent validity and strong relative accuracy with the 1MRW model.

  20. VO2 kinetics and metabolic contributions whilst swimming at 95, 100, and 105% of the velocity at VO2max.

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    Sousa, Ana C; Vilas-Boas, João P; Fernandes, Ricardo J

    2014-01-01

    A bioenergetical analysis of swimming at intensities near competitive distances is inexistent. It was aimed to compare the transient VO2 kinetics responses and metabolic contributions whilst swimming at different velocities around VO2max. 12 trained male swimmers performed (i) an incremental protocol to determine the velocity at VO2max (vVO2max) and (ii) three square wave exercises from rest to 95, 100, and 105% of vVO2max. VO2 was directly measured using a telemetric portable gas analyser and its kinetics analysed through a double-exponential model. Metabolic contributions were assessed through the sum of three energy components. No differences were observed in the fast component response (τ1--15, 18, and 16 s, A1--36, 34, and 37 mL · kg(-1) · min (-1), and Gain--32, 29, and 30 mL · min (-1) at 95, 100, and 105% of the vVO2max, resp.) but A2 was higher in 95 and 100% compared to 105% intensity (480.76 ± 247.01, 452.18 ± 217.04, and 147.04 ± 60.40 mL · min (-1), resp.). The aerobic energy contribution increased with the time sustained (83 ± 5, 74 ± 6, and 59 ± 7% for 95, 100, and 105%, resp.). The adjustment of the cardiovascular and/or pulmonary systems that determine O2 delivery and diffusion to the exercising muscles did not change with changing intensity, with the exception of VO2 slow component kinetics metabolic profiles.

  1. Individual versus Standardized Running Protocols in the Determination of VO2max

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    Paula F. Sperlich, Hans-Christer Holmberg, Jennifer L. Reed, Christoph Zinner, Joachim Mester, Billy Sperlich

    2015-06-01

    Full Text Available The purpose of this study was to determine whether an individually designed incremental exercise protocol results in greater rates of oxygen uptake (VO2max than standardized testing. Fourteen well-trained, male runners performed five incremental protocols in randomized order to measure their VO2max: i an incremental test (INCS+I with pre-defined increases in speed (2 min at 8.64 km·h−1, then a rise of 1.44 km·h−1 every 30 s up to 14.4 km·h−1 and thereafter inclination (0.5° every 30 s; ii an incremental test (INCI at constant speed (14.4 km·h−1 and increasing inclination (2° every 2 min from the initial 0°; iii an incremental test (INCS at constant inclination (0° and increasing speed (0.5 km·h−1 every 30 s from the initial 12.0 km·h−1; iv a graded exercise protocol (GXP at a 1° incline with increasing speed (initially 8.64 km·h−1 + 1.44 km·h−1 every 5 min; v an individual exercise protocol (INDXP in which the runner chose the inclination and speed. VO2max was lowest (-4.2% during the GXP (p = 0.01; d = 0.06-0.61 compared to all other tests. The highest rating of perceived exertion, heart rate, ventilation and end-exercise blood lactate concentration were similar between the different protocols (p < 0.05. The time to exhaustion ranged from 7 min 18 sec (INCS to 25 min 30 sec (GXP (p = 0.01.The VO2max attained by employing an individual treadmill protocol does not differ from the values derived from various standardized incremental protocols.

  2. Relationship between running kinematic changes and time limit at vVO2max. DOI: http://dx.doi.org/10.5007/1980-0037.2012v14n4p428

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    Sebastião Iberes Lopes Melo

    2012-07-01

    Full Text Available DOI: http://dx.doi.org/10.5007/1980-0037.2012v14n4p428Exhaustive running at maximal oxygen uptake velocity (vVO2max can alter running kinematic parameters and increase energy cost along the time. The aims of the present study were to compare characteristics of ankle and knee kinematics during running at vVO2max and to verify the relationship between changes in kinematic variables and time limit (Tlim. Eleven male volunteers, recreational players of team sports, performed an incremental running test until volitional exhaustion to determine vVO2max and a constant velocity test at vVO2max. Subjects were filmed continuously from the left sagittal plane at 210 Hz for further kinematic analysis. The maximal plantar flexion during swing (p<0.01 was the only variable that increased significantly from beginning to end of the run. Increase in ankle angle at contact was the only variable related to Tlim (r=0.64; p=0.035 and explained 34% of the performance in the test. These findings suggest that the individuals under study maintained a stable running style at vVO2max and that increase in plantar flexion explained the performance in this test when it was applied in non-runners.

  3. Efeito da intensidade do exercício de corrida intermitente 30s:15s no tempo de manutenção no ou próximo do VO2max Effect of intensity of intermittent running exercise 30s:15s at the time maintenance at or near VO2max

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    Rafael Alves de Aguiar

    2013-03-01

    Full Text Available O presente estudo comparou o tempo mantido acima de 90% (t90VO2max e de 95% VO2max (t95VO2max em três diferentes intensidades de exercício. Após a realização de um teste incremental para determinar o VO2max, oito estudantes de educação física ativos (23 ± 3 anos executaram três sessões de exercícios intermitentes (100, 110 e 120% da velocidade do VO2max (vVO2max com razão esforço:recuperação de 30s:15s. O t95VO2max foi significantemente maior em 110%vVO2max (EI110% (218,1 ± 81,6 s quando comparado a 100%vVO2max (EI100% (91,9 ± 75,2s e a 120%vVO2max (EI120% (126,3 ± 29,4 s, porém sem diferença entre EI100% e EI120%. O t90VO2max somente apresentou diferença significante entre EI110% e EI120%. Portanto, conclui-se que durante exercício intermitente com razão 30s:15s, a intensidade de 110%vVO2max apresenta-se mais adequada para manter o VO2 próximo ou no VO2max por um tempo maior.The present study compared the time maintained above 90% (t90VO2max or 95% VO2max (t95VO2max in three different exercise intensities. After performing an incremental test to determine VO2max, eight physical education active students (23 ± 3 years performed three intermittent exercise sessions (100, 110 e 120% velocity of VO2max (vVO2max with ratio effort:recovery of 30s:15s. The t95%VO2max was significantly higher at 110%vVO2max (EI110% (218.1 ± 81.6s compared to 100% vVO2max (EI100% (91.9 ± 75.2s and 120%vVO2max (EI120% (126.3 ± 29.4s, but without differences between EI100% and EI120%. The t90%vVO2max was significantly different only between EI110% and 120%. Therefore, we conclude that during intermittent exercise with ratio 30s:15s, the intensity of 110%vVO2max appears more appropriate to maintain VO2max for a longer time.

  4. Crossvalidation of two 20-m shuttle-run tests for predicting VO2max in female collegiate soccer players.

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    Green, Michael S; Esco, Michael R; Martin, Tyler D; Pritchett, Robert C; McHugh, Aindrea N; Williford, Henry N

    2013-06-01

    The aim of this study was twofold: (a) to compare the maximal attained speed (MAS) from the 20-m shuttle (MST) and 20-m square-shuttle (SST) tests and (b) to crossvalidate 2 equations for predicting maximal oxygen consumption (VO2max) that were previously developed from MST and SST in a group of female collegiate soccer players. Thirty-nine subjects (age: 20.1 ± 1.5 years) participated in the study. A maximal graded exercise treadmill test was used to measure VO2max. In addition, VO2max was predicted from the MAS obtained during MST ((pred)VO2maxMST) and SST ((pred)VO2maxSST) using previously developed equations. Measured VO2max for the group was 44.2 ± 3.3 ml·kg(-1)·min(-1). The MAS was 12.5 ± 0.6 km·h(-1) for MST and 13.3 ± 0.8 km·h(-1) for SST (p < 0.05). The prediction methods yielded a (pred)VO2maxMST of 49.6 ± 3.9 ml·kg(-1)·min(-1) and predVO2maxSST of 41.8 ± 3.1 ml·kg(-1)·min(-1), which were significantly different from measured VO2max (p < 0.05). The validity statistics revealed the following constant error (CE), correlation coefficient (r), standard error of estimate (SEE), and total error (TE) for (pred)VO2maxMST and (pred)VO2maxSST: CE = 5.35 ± 3.83, r = 0.45 (p < 0.05), SEE = 2.97 ml·kg(-1)·min(-1), TE = 6.39 ml·kg(-1)·min(-1); and CE = -2.43 ± 2.49, r = 0.69 (p < 0.05), SEE = 2.39 ml·kg(-1)·min(-1), TE = 3.43 ml·kg(-1)·min(-1), respectively. Residual plots indicated no proportional bias for either prediction model. The results of this study suggest that female collegiate soccer players had a higher MAS from SST compared with that from MST. In addition, SST appeared to be a more accurate predictor of VO2max than MST in the group of athletes.

  5. Comparison of VO2 Max Prediction Value, Physiological Response, and Borg Scale between 12-Minute and 3200-Meter Run Fitness Tests among Indonesian Army Soldiers

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    Maulidi Abdillah

    2016-09-01

    Full Text Available Objective: To compare the VO2 max and physiological responses between 12-minute and 3200-meter run fitness tests. Methods: The subjects were 40 soldiers aged 18–21 years old of the Infantry Battalion 303/SSM of Cikajang, Garut, West Java, Indonesia. The 12-minute and 3200-meter run fitness tests were conducted with one week resting period. The measurement of the VO2 max prediction was based on each of the formulations and the measurement of physiological response included blood pressure, heart rate, respiratory rate, Borg scale and oxygen saturation before and after the tests. This study used a cross-sectional method while the data were analyzed statistically using t-test (p=0.05. Results: The results showed that the VO2 max prediction in 12-minute run fitness test was 52.046±2.980 mL/KgBB/min and the 3200-meter run test was 55.323±3.238 mL/KgBB/min. The value was statistically significant (p=0.008. There was no significant difference in the physiological response in both tests, except the SpO2 parameter after the tests (p=0.021. Conclusions: There is a significant difference in VO2 max prediction between 12 minutes and 3200 meter run test. No significant difference was found in the physiological response in both tests, except the SpO2 parameter.

  6. A comparison of time to exhaustion at VO2 max in élite cyclists, kayak paddlers, swimmers and runners.

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    Billat, V; Faina, M; Sardella, F; Marini, C; Fanton, F; Lupo, S; Faccini, P; de Angelis, M; Koralsztein, J P; Dalmonte, A

    1996-02-01

    A recent study has shown the reproducibility of time to exhaustion (time limit: tlim) at the lowest velocity that elicits the maximal oxygen consumption (vVO2 max). The same study found an inverse relationship between this time to exhaustion at vVO2 max and vVO2 max among 38 élite long-distance runners (Billat et al. 1994b). The purpose of the present study was to compare the time to exhaustion at the power output (or velocity) at VO2 max for different values of VO2 max, depending on the type of exercise and not only on the aerobic capacity. The time of exhaustion at vVO2 max (tlim) has been measured among 41 élite (national level) sportsmen: 9 cyclists, 9 kayak paddlers, 9 swimmers and 14 runners using specific ergometers. Velocity or power at VO2 max (vVO2 max) was determined by continuous incremental testing. This protocol had steps of 2 min and increments of 50 W, 30 W, 0.05 m s-1 and 2 km-1 for cyclists, kayak paddlers, swimmers and runners, respectively. One week later, tlim was determined under the same conditions. After a warm-up of 10 min at 60% of their vVO2 max, subjects were concluded (in less than 45 s) to their vVO2 max and then had to sustain it as long as possible until exhaustion. Mean values of vVO2 max and tlim were respectively equal to 419 +/- 49 W (tlim = 222 +/- 91 s), 239 +/- 56 W (tlim = 376 +/- 134 s), 1.46 +/- 0.09 m s-1 (tlim = 287 +/- 160 s) and 22.4 +/- 0.8 km h-1 (tlim = 321 +/- 84 s), for cyclists, kayak paddlers, swimmers and runners. Time to exhaustion at vVO2 max was only significantly different between cycling and kayaking (ANOVA test, p < 0.05). Otherwise, VO2 max (expressed in ml min-1 kg-1) was significantly different between all sports except between cycling and running (p < 0.05). In this study, time to exhaustion at vVO2 max was also inversely related to VO2 max for the entire group of élite sportsmen (r = -0.320, p < 0.05, n = 41). The inverse relationship between VO2 max and tlim at vVO2 max has to be explained, it

  7. [Effect of 4 weeks of training on the limit time at VO2 max].

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    Heubert, Richard; Bocquet, Valéry; Koralsztein, Jean Pierre; Billat, Véronique

    2003-10-01

    The purpose of this study was to examine the effect of 4 weeks training in running on the time spent at VO2max (tlim VO2max). Eight athletes carried out, before and after an aerobic training, an incremental and five exhaustive tests at 90, 95, 100, 115% vVO2max and at the critical power at VO2max (CV'; slope of the linear relation between the tlim VO2max and the distance limit at VO2max). This training did not significantly improve VO2max (p = 0.17) or tlim VO2max (p = 0.72). However, the "tlim VO2max-intensity" curve was shifted toward the right, meaning that the athlete had to run at a higher intensity after training to obtain the same tlim VO2max. Tlim VO2max at CV' before training was significantly higher than tlim VO2max at 90, 95, 100, and 115% vVO2max (p max; p = 0.9). In conclusion, in spite of the shift of the "tlim VO2max-intensity" curve, tlim VO2max was not significantly increased by this training. Furthermore, CV' allowed subjects to spend the longest time of exercise at VO2max during a continuous exercise with constant speed, but CV', expressed in % vVO2max, did not improve with this training.

  8. Influence of work-interval intensity and duration on time spent at a high percentage of VO2max during intermittent supramaximal exercise.

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    Wakefield, Benjamin R; Glaister, Mark

    2009-12-01

    The purpose of this study was to examine the effect of work-interval duration (WID) and intensity on the time spent at, or above, 95% VO2max (T95 VO2max) during intermittent bouts of supramaximal exercise. Over a 5-week period, 7 physically active men with a mean (+/-SD) age, height, body mass, and VO2max of 22 +/- 5 years, 181.5 +/- 5.6 cm, 86.4 +/- 11.4 kg, and 51.5 +/- 1.5 ml.kg-1.min-1, respectively, attended 7 testing sessions. After completing a submaximal incremental test on a treadmill to identify individual oxygen uptake/running velocity relationships, subjects completed a maximal incremental test to exhaustion to VO2max and subsequently (from the aforementioned relationship) the minimum velocity required to elicit VO2max (vVO2max). In a random order, subjects then carried out 3 intermittent runs to exhaustion at both 105% and 115% vVO2max. Each test used a different WID (20 s, 25 s, or 30 s) interspersed with 20-second passive recovery periods. Results revealed no significant difference in T95 vVO2max for intermittent runs at 105% versus 115% vVO2max (p = 0.142). There was, however, a significant effect (p VO2max, with WIDs of 30 seconds enabling more time relative to WIDs of 20 seconds (p = 0.018) and 25 seconds (p = 0.009). Moreover, there was an interaction between intensity and duration such that the effect of WID was magnified at the lower exercise intensity (p = 0.046). In conclusion, despite a number of limitations, the results of this investigation suggest that exercise intensities of approximately 105% vVO2max combined with WIDs greater than 25 seconds provide the best way of optimizing T95 VO2max when using fixed 20-second stationary rest periods.

  9. Estimation of VO2 Max: A Comparative Analysis of Five Exercise Tests.

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    Zwiren, Linda D.; And Others

    1991-01-01

    Thirty-eight healthy females measured maximal oxygen uptake (VO2max) on the cycle ergometer and treadmill to compare five exercise tests (run, walk, step, and two tests using heart-rate response on the bicycle ergometer) in predicting VO2max. Results indicate that walk and run tests are satisfactory predictors of VO2max in 30- to 39-year-old…

  10. Efeito da intensidade do exercício de corrida intermitente 30s:15s no tempo de manutenção no ou próximo do VO2max Effect of intensity of intermittent running exercise 30s:15s at the time maintenance at or near VO2max

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    Rafael Alves de Aguiar; Jardel Schlickmann; Tiago Turnes; Fabrizio Caputo

    2013-01-01

    O presente estudo comparou o tempo mantido acima de 90% (t90VO2max) e de 95% VO2max (t95VO2max) em três diferentes intensidades de exercício. Após a realização de um teste incremental para determinar o VO2max, oito estudantes de educação física ativos (23 ± 3 anos) executaram três sessões de exercícios intermitentes (100, 110 e 120% da velocidade do VO2max (vVO2max)) com razão esforço:recuperação de 30s:15s. O t95VO2max foi significantemente maior em 110%vVO2max (EI110%) (218,1 ± 81,6 s) quan...

  11. Reproducibility of maximum aerobic power (VO2max) among soccer players using a modified heck protocol.

    Science.gov (United States)

    Santos-Silva, Paulo Roberto; Fonseca, Alfredo José; Castro, Anita Weigand de; Greve, Júlia Maria D'Andréa; Hernandez, Arnaldo José

    2007-08-01

    To determine the degree of reproducibility of maximum oxygen consumption (VO2max) among soccer players, using a modified Heck protocol. 2 evaluations with an interval of 15 days between them were performed on 11 male soccer players. All the players were at a high performance level; they were training for an average of 10 hours per week, totaling 5 times a week. When they were evaluated, they were in the middle of the competitive season, playing 1 match per week. The soccer players were evaluated on an ergometric treadmill with velocity increments of 1.2 km.h-1 every 2 minutes and a fixed inclination of 3% during the test. VO2max was measured directly using a breath-by-breath metabolic gas analyzer. The maximum running speed and VO2max attained in the 2 tests were, respectively: (15.6 +/- 1.1 vs. 15.7 +/- 1.2 km.h-1; [P = .78]) and (54.5 +/- 3.9 vs. 55.2 +/- 4.4 ml.kg-1.min-1; [P = .88]). There was high and significant correlation of VO2max between the 2 tests with a 15-day interval between them [r = 0.97; P testing was insufficient to significantly modify the soccer players' VO2max values.

  12. Gas exchange threshold and VO2max testing for athletes: an update.

    Science.gov (United States)

    Pettitt, Robert W; Clark, Ida E; Ebner, Stacy M; Sedgeman, Daniel T; Murray, Steven R

    2013-02-01

    Standardized graded exercise test (GXT) protocols are ineffective for testing endurance athletes. Scientists have called for the abandonment of traditional techniques for corroborating "true" maximum oxygen uptake (VO2max), as measured during a GXT. Instead, a new technique, the verification bout subsequent to the GXT, has emerged for establishing the "true" VO2max. The addition of the verification bout reframes how the GXT should be viewed. In this article, we summarize the methods for developing custom GXT protocols, identifying threshold and interpolating power or outdoor running velocity, and implicating the verification bout.

  13. Health-Related Physical Fitness in Healthy Untrained Men: Effects on VO2max, Jump Performance and Flexibility of Soccer and Moderate-Intensity Continuous Running.

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    Zoran Milanović

    Full Text Available The purpose of this study was to determine the effects of recreational soccer (SOC compared to moderate-intensity continuous running (RUN on all health-related physical fitness components in healthy untrained men. Sixty-nine participants were recruited and randomly assigned to one of three groups, of which sixty-four completed the study: a soccer training group (SOC; n = 20, 34±4 (means±SD years, 78.1±8.3 kg, 179±4 cm; a running group (RUN; n = 21, 32±4 years, 78.0±5.5 kg, 179±7 cm; or a passive control group (CON; n = 23, 30±3 years, 76.6±12.0 kg, 178±8 cm. The training intervention lasted 12 weeks and consisted of three 60-min sessions per week. All participants were tested for each of the following physical fitness components: maximal aerobic power, minute ventilation, maximal heart rate, squat jump (SJ, countermovement jump with arm swing (CMJ, sit-and-reach flexibility, and body composition. Over the 12 weeks, VO2max relative to body weight increased more (p<0.05 in SOC (24.2%, ES = 1.20 and RUN (21.5%, ES = 1.17 than in CON (-5.0%, ES = -0.24, partly due to large changes in body mass (-5.9, -5.7 and +2.6 kg, p<0.05 for SOC, RUN and CON, respectively. Over the 12 weeks, SJ and CMJ performance increased more (p<0.05 in SOC (14.8 and 12.1%, ES = 1.08 and 0.81 than in RUN (3.3 and 3.0%, ES = 0.23 and 0.19 and CON (0.3 and 0.2%, while flexibility also increased more (p<0.05 in SOC (94%, ES = 0.97 than in RUN and CON (0-2%. In conclusion, untrained men displayed marked improvements in maximal aerobic power after 12 weeks of soccer training and moderate-intensity running, partly due to large decreases in body mass. Additionally soccer training induced pronounced positive effects on jump performance and flexibility, making soccer an effective broad-spectrum fitness training intervention.

  14. Multi-Stage 20-m Shuttle Run Fitness Test, Maximal Oxygen Uptake and Velocity at Maximal Oxygen Uptake

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    Paradisis Giorgos P.

    2014-07-01

    Full Text Available The multi-stage 20-m shuttle run fitness test (20mMSFT is a popular field test which is widely used to measure aerobic fitness by predicting maximum oxygen uptake (VO2 max and performance. However, the velocity at which VO 2 max occurs (vVO 2 max is a better indicator of performance than VO 2 max, and can be used to explain inter-individual differences in performance that VO 2 max cannot. It has been reported as a better predictor for running performance and it can be used to monitor athletes’ training for predicting optimal training intensity. This study investigated the validity and suitability of predicting VO2max and vVO2max of adult subjects on the basis of the performance of the 20mMST. Forty eight (25 male and 23 female physical education students performed, in random order, a laboratory based continuous horizontal treadmill test to determine VO2max, vVO 2 max and a 20mMST, with an interval of 3 days between each test. The results revealed significant correlations between the number of shuttles in the 20mMSFT and directly determined VO 2 max (r = 0.87, p<0.05 and vVO 2 max (r = 0.93, p<0.05. The equation for prediction of VO 2 max was y = 0.0276x + 27.504, whereas for vVO 2 max it was y = 0.0937x + 6.890. It can be concluded that the 20mMSFT can accurately predict VO 2 max and vVO 2 max and this field test can provide useful information regarding aerobic fitness of adults. The predicted vVO 2 max can be used in monitoring athletes, especially in determining optimal training intensity.

  15. Multi-Stage 20-m Shuttle Run Fitness Test, Maximal Oxygen Uptake and Velocity at Maximal Oxygen Uptake.

    Science.gov (United States)

    Paradisis, Giorgos P; Zacharogiannis, Elias; Mandila, Dafni; Smirtiotou, Athanasia; Argeitaki, Polyxeni; Cooke, Carlton B

    2014-06-28

    The multi-stage 20-m shuttle run fitness test (20mMSFT) is a popular field test which is widely used to measure aerobic fitness by predicting maximum oxygen uptake (VO2max) and performance. However, the velocity at which VO2max occurs (vVO2max) is a better indicator of performance than VO2max, and can be used to explain inter-individual differences in performance that VO2max cannot. It has been reported as a better predictor for running performance and it can be used to monitor athletes' training for predicting optimal training intensity. This study investigated the validity and suitability of predicting VO2max and vVO2max of adult subjects on the basis of the performance of the 20mMST. Forty eight (25 male and 23 female) physical education students performed, in random order, a laboratory based continuous horizontal treadmill test to determine VO2max, vVO2max and a 20mMST, with an interval of 3 days between each test. The results revealed significant correlations between the number of shuttles in the 20mMSFT and directly determined VO2max (r = 0.87, pVO2max was y = 0.0276x + 27.504, whereas for vVO2max it was y = 0.0937x + 6.890. It can be concluded that the 20mMSFT can accurately predict VO2max and vVO2max and this field test can provide useful information regarding aerobic fitness of adults. The predicted vVO2max can be used in monitoring athletes, especially in determining optimal training intensity.

  16. Test of the classic model for predicting endurance running performance.

    Science.gov (United States)

    McLaughlin, James E; Howley, Edward T; Bassett, David R; Thompson, Dixie L; Fitzhugh, Eugene C

    2010-05-01

    To compare the classic physiological variables linked to endurance performance (VO2max, %VO2max at lactate threshold (LT), and running economy (RE)) with peak treadmill velocity (PTV) as predictors of performance in a 16-km time trial. Seventeen healthy, well-trained distance runners (10 males and 7 females) underwent laboratory testing to determine maximal oxygen uptake (VO2max), RE, percentage of maximal oxygen uptake at the LT (%VO2max at LT), running velocity at LT, and PTV. Velocity at VO2max (vVO2max) was calculated from RE and VO2max. Three stepwise regression models were used to determine the best predictors (classic vs treadmill performance protocols) for the 16-km running time trial. Simple Pearson correlations of the variables with 16-km performance showed vVO2max to have the highest correlation (r = -0.972) and %VO2max at the LT the lowest (r = 0.136). The correlation coefficients for LT, VO2max, and PTV were very similar in magnitude (r = -0.903 to r = -0.892). When VO2max, %VO2max at LT, RE, and PTV were entered into SPSS stepwise analysis, VO2max explained 81.3% of the total variance, and RE accounted for an additional 10.7%. vVO2max was shown to be the best predictor of the 16-km performance, accounting for 94.4% of the total variance. The measured velocity at VO2max (PTV) was highly correlated with the estimated velocity at vVO2max (r = 0.8867). Among well-trained subjects heterogeneous in VO2max and running performance, vVO2max is the best predictor of running performance because it integrates both maximal aerobic power and the economy of running. The PTV is linked to the same physiological variables that determine vVO2max.

  17. [VO2 max, a true exercise test].

    Science.gov (United States)

    Saunier, Carole

    2013-01-01

    VO2 max is nowadays an essential examination performed in the monitoring of heart failure. The nurse has a role to play during the test and in supporting the patient, although this test remains highly technical and complex.

  18. Indirect estimation of VO2max in athletes by ACSM’s equation: valid or not?

    Science.gov (United States)

    Koutlianos, N; Dimitros, E; Metaxas, T; Cansiz, M; Deligiannis, AS; Kouidi, E

    2013-01-01

    Aim: The purpose of this study was to assess the indirect calculation of VO2max using ACSM’s equation for Bruce protocol in athletes of different sports and to compare with the directly measured; secondly to develop regression models predicting VO2 max in athletes. Methods: Fifty five male athletes of national and international level (mean age 28.3 ± 5.6 yrs) performed graded exercise test with direct measurement of VO2 through ergospirometric device. Moreover, 3 equations were used for the indirect calculation of VO2max: a) VO2max= (0.2 · Speed) + (0.9 · Speed · Grade) + 3.5 (ACSM running equation), b) regression analysis model using enter method and c) stepwise method based on the measured data of VO2. Age, BMI, speed, grade and exercise time were used as independent variables. Results: Regression analysis using enter method yielded the equation (R=.64, standard error of estimation [SEE] = 6.11): VO2max (ml·kg-1·min-1) = 58.443 - (0.215 · age) - (0.632 · BMI) - (68.639 · grade) + (1.579 · time) while stepwise method (R = .61, SEE = 6.18) led to: VO2max (ml·kg-1·min-1) = 33.971 - (0.291 · age) + (1.481 · time). The calculated values of VO2max from these regression models did not differ significantly from the measured VO2max (p>.05). On the contrary, VO2max calculated from the ACSM’s running equation was significantly higher from the actually measured value by 14.6% (p VO2max in athletes aged 18-37 years using Bruce protocol. Only the regression models were correlated moderately with the actually measured values of VO2max. PMID:24376318

  19. Indirect estimation of VO2max in athletes by ACSM's equation: valid or not?

    Science.gov (United States)

    Koutlianos, N; Dimitros, E; Metaxas, T; Cansiz, M; Deligiannis, As; Kouidi, E

    2013-04-01

    The purpose of this study was to assess the indirect calculation of VO2max using ACSM's equation for Bruce protocol in athletes of different sports and to compare with the directly measured; secondly to develop regression models predicting VO2 max in athletes. Fifty five male athletes of national and international level (mean age 28.3 ± 5.6 yrs) performed graded exercise test with direct measurement of VO2 through ergospirometric device. Moreover, 3 equations were used for the indirect calculation of VO2max: a) VO2max= (0.2 · Speed) + (0.9 · Speed · Grade) + 3.5 (ACSM running equation), b) regression analysis model using enter method and c) stepwise method based on the measured data of VO2. Age, BMI, speed, grade and exercise time were used as independent variables. Regression analysis using enter method yielded the equation (R=.64, standard error of estimation [SEE] = 6.11): VO2max (ml·kg(-1)·min(-1)) = 58.443 - (0.215 · age) - (0.632 · BMI) - (68.639 · grade) + (1.579 · time) while stepwise method (R = .61, SEE = 6.18) led to: VO2max (ml·kg(-1)·min(-1)) = 33.971 - (0.291 · age) + (1.481 · time). The calculated values of VO2max from these regression models did not differ significantly from the measured VO2max (p>.05). On the contrary, VO2max calculated from the ACSM's running equation was significantly higher from the actually measured value by 14.6% (p VO2max in athletes aged 18-37 years using Bruce protocol. Only the regression models were correlated moderately with the actually measured values of VO2max.

  20. VO2 max in an Indian population: a study to understand the role of factors determining VO2 max.

    Science.gov (United States)

    Nitin, Y M; Sucharita, S; Madhura, M; Thomas, T; Sandhya, T A

    2013-01-01

    VO2 max is the maximum amount of oxygen a person can consume and the value does not change despite an increase in workload. There is lack of data evaluating the impact of factors, which could affect VO2 max measurement, particularly in Indian population. The objectives of the present study were (i) to estimate VO2 max in a young healthy Indian population and to compare it with available prediction equations for Indian population (ii) to correlate time to achieve VO2 max with the relative VO2 max (iii) to assess the factors affecting the time to achieve VO2 max measurement (body composition and physical activity level). Twenty healthy adult males (18-30 years) underwent detailed anthropometry, physical activity level and modified Bruce protocol for VO2 max assessment. Breath by breath VO2, VCO2, oxygen saturation, heart rate, blood pressure were measured continuously and following exercise protocol. There was an internal validity between the estimated VO2 max and the maximum heart rate (MHR) (r = 0.51, P VO2 max P VO2 max. Out of the 3 prediction equations computed to estimate VO2 max, 2 equations significantly overestimated VO2 max. In Conclusion, physical activity level emerged to be a strong predictor of time to VO2 max. Time to achieve VO2 max is an important factor to be considered when determining VO2 max. There was an overestimation in the VO2 max values derived from predicted equations.

  1. Fitness self-perception and Vo2max in firefighters.

    Science.gov (United States)

    Peate, W F; Lundergan, Linda; Johnson, Jerry J

    2002-06-01

    Firefighters work at maximal levels of exertion. Fitness for such duty requires adequate aerobic capacity (maximum oxygen consumption [Vo2max]). Aerobic fitness can both improve a worker's ability to perform and offer resistance to cardiopulmonary conditions. Inactive firefighters have a 90% greater risk of myocardial infarction than those who are aerobically fit. Participants (101 firefighters) completed a questionnaire that asked them to rank their fitness level from 0 to 7; e.g., Level 0 was low fitness: "I avoid walking or exertion, e.g., always use elevator, drive whenever possible." The level of activity rating increased to Level 7: "I run over 10 miles per week or spend 3 hours per week in comparable physical activity." Each participant then completed two measures of Vo2max: a 5-minute step test and a submaximal treadmill test. There was no association between the firefighters' self-perception of their level of fitness and their aerobic capacity as measured by either step test or submaximal treadmill. Because of the critical job demands of firefighting and the negative consequences of inadequate fitness and aerobic capacity, periodic aerobic capacity testing with individualized exercise prescriptions and work--community support may be advisable for all active-duty firefighters.

  2. Echinacea purpurea supplementation does not enhance VO2max in distance runners.

    Science.gov (United States)

    Baumann, Cory W; Bond, Kelsey L; Rupp, Jeffrey C; Ingalls, Christopher P; Doyle, J Andrew

    2014-05-01

    Oral supplementation of Echinacea purpurea (ECH) has been reported to increase levels of serum erythropoietin and as a result improve endurance performance in untrained subjects. The purpose of this study was to determine if ECH supplementation alters maximal oxygen uptake (VO2max) in trained endurance runners. Using a double-blind design, 16 trained endurance runners (9 ECH and 7 placebo [PLA]) supplemented with either 8,000 mg·d(-1) of ECH or wheat flour (PLA) for 6 weeks. Maximal aerobic treadmill tests and blood samples were measured before and after supplementation to determine VO2max, hematocrit (Hct), and hemoglobin (Hb). VO2max, Hct, and Hb did not differ between the ECH and PLA groups before or after supplementation. Furthermore, supplementation of ECH failed to improve VO2max (67.37 ± 4.62 vs. 67.23 ± 5.82 ml·kg(-1)·min(-1)), Hct (43.57 ± 2.38 vs. 42.85 ± 1.46%), or Hb (14.93 ± 1.27 vs. 15.55 ± 0.80 g·dL(-1)) from baseline measurements. Echinacea purpurea supplementation of 8,000 mg·d(-1) for 6 weeks failed to increase VO2max, Hct, or Hb in trained endurance runners and thus does not seem to influence physiological variables that affect distance running performance.

  3. The Effect of Habitual Smoking on VO2max

    Science.gov (United States)

    Wier, Larry T.; Suminski, Richard R.; Poston, Walker S.; Randles, Anthony M.; Arenare, Brian; Jackson, Andrew S.

    2008-01-01

    VO2max is associated with many factors, including age, gender, physical activity, and body composition. It is popularly believed that habitual smoking lowers aerobic fitness. PURPOSE: to determine the effect of habitual smoking on VO2max after controlling for age, gender, activity and BMI. METHODS: 2374 men and 375 women employed at the NASA/Johnson Space Center were measured for VO2max by indirect calorimetry (RER>=1.1), activity by the 11 point (0-10) NASA Physical Activity Status Scale (PASS), BMI and smoking pack-yrs (packs day*y of smoking). Age was recorded in years and gender was coded as M=1, W=0. Pack.y was made a categorical variable consisting of four levels as follows: Never Smoked (0), Light (1-10), Regular (11-20), Heavy (>20). Group differences were verified by ANOVA. A General Linear Models (GLM) was used to develop two models to examine the relationship of smoking behavior on VO2max. GLM #1(without smoking) determined the combined effects of age, gender, PASS and BMI on VO2max. GLM #2 (with smoking) determined the added effects of smoking (pack.y groupings) on VO2max after controlling for age, gender, PASS and BMI. Constant errors (CE) were calculated to compare the accuracy of the two models for estimating the VO2max of the smoking subgroups. RESULTS: ANOVA affirmed the mean VO2max of each pack.y grouping decreased significantly (psmoking exposure increased. GLM #1 showed that age, gender, PASS and BMI were independently related with VO2max (R2 = 0.642, SEE = 4.90, pSmoked, the effects on VO2max from Light and Regular smoking habits were -0.83 and -0.85 ml.kg- 1.min-1 respectively (peffect of Heavy smoking on VO2max was -2.56 ml.kg- 1.min-1 (psmoking group in GLM #2 was smaller than the CE s of the smoking group counterparts in GLM #1. CONCLUSIONS: After accounting for the effects of gender, age, PASS and BMI the effect of habitual smoking on reducing VO2max is minimal, about 0.85 ml/kg/min, until the habit exceeds 20 pack.y at which point an

  4. Factors determining the time course of VO2(max) decay during bedrest: implications for VO2(max) limitation.

    Science.gov (United States)

    Capelli, C; Antonutto, G; Kenfack, M Azabji; Cautero, M; Lador, F; Moia, C; Tam, E; Ferretti, G

    2006-09-01

    The aim of this study was to characterize the time course of maximal oxygen consumption VO2(max) changes during bedrests longer than 30 days, on the hypothesis that the decrease in VO2(max) tends to asymptote. On a total of 26 subjects who participated in one of three bedrest campaigns without countermeasures, lasting 14, 42 and 90 days, respectively, VO2(max) maximal cardiac output (Qmax) and maximal systemic O2 delivery (QaO2max) were measured. After all periods of HDT, VO2max, Qmax, and QaO2max were significantly lower than before. The VO2max decreased less than qmax after the two shortest bedrests, but its per cent decay was about 10% larger than that of Qmax after 90-day bedrest. The VO2max decrease after 90-day bedrest was larger than after 42- and 14-day bedrests, where it was similar. The Qmax and QaO2max declines after 90-day bedrest was equal to those after 14- and 42-day bedrest. The average daily rates of the VO2max, Qmax, and QaO2max decay during bedrest were less if the bedrest duration were longer, with the exception of that of VO2max in the longest bedrest. The asymptotic VO2max decay demonstrates the possibility that humans could keep working effectively even after an extremely long time in microgravity. Two components in the VO2max decrease were identified, which we postulate were related to cardiovascular deconditioning and to impairment of peripheral gas exchanges due to a possible muscle function deterioration.

  5. Leg strength and the VO2 max of older men.

    Science.gov (United States)

    Lovell, D; Cuneo, R; Delphinus, E; Gass, G

    2011-04-01

    The purpose of the study was to determine if leg strength limits VO2 max and the ability to reach a plateau during VO2 max test in older men during cycle ergometry. Men aged 70-80 years were randomly selected into a strength training (ST, n=12) 3 times weekly for 16 weeks, followed by 4 weeks detraining or a non-training control group (C, n=12). Leg strength and VO2 max were assessed every 4 weeks for 20 weeks; body composition and cardiac function were assessed before and after 16 weeks training and after 4 weeks detraining. Leg strength, upper leg muscle mass (ULMM), arterial-venous O2 difference (a-v O2 difference) and VO2 max increased in the ST group (95±0.6%, 7±0.7%. 6.2±0.5% and 8±0.8%, respectively; PVO2 max and a-v O2 difference returned to pre-training levels. There was no change in the ability of the participants to reach a plateau during VO2 max testing over the 20-week study. These findings indicate that leg strength may not limit either VO2 max or the ability to plateau during VO2 max tests in older men during cycle ergometry. © Georg Thieme Verlag KG Stuttgart · New York.

  6. Assessment of anaerobic power to verify VO2max attainment.

    Science.gov (United States)

    Astorino, Todd A; White, Ailish C

    2010-07-01

    Across various populations, verification testing is used to confirm VO(2)max attainment and has repeatedly shown similar VO(2)max values to those obtained from incremental exercise. Yet, many individuals show meaningful differences in VO(2)max between protocols, and an explanation for this is unknown. The aim of the study was to elucidate this phenomenon in 30 men and women of similar age, fitness, and physical activity using assessment of anaerobic power. On day 1, they completed the Wingate test, and returned at least 48 h later to complete incremental cycle ergometry followed by a verification protocol. During exercise, ventilation, pulmonary gas exchange data, and heart rate (HR) were continuously measured. Mean VO(2)max was similar (P > 0.05) between protocols (42.05 +/- 5.88 ml kg(-1) per min versus 42.03 +/- 5.75 ml kg(-1) per min, respectively), although seven subjects (23%) revealed a VO(2)max that was not 'verified' by the supramaximal protocol. Indices of power output and gas exchange data were similar (P > 0.05) between subjects who revealed a 'true' VO(2)max compared to those who did not, although peak and mean power was consistently higher in persons whose VO(2)max was not 'verified.' A previously established HRmax criterion for verification testing was not met in 17% of subjects. Additional study is merited to identify alternate determinants of VO(2)max, such as muscle activation via assessment of motor unit recruitment, and to investigate utility of verification testing to confirm VO(2)max attainment in elite athletes and the elderly.

  7. VO2 Max in Variable Type Exercise Among Well-Trained Upper Body Athletes.

    Science.gov (United States)

    Seals, Douglas R.; Mullin, John P.

    1982-01-01

    The maximal oxygen consumption (VO2 max) of well-trained upper body athletes was compared to that of untrained individuals in four types of exercise: arm cranking, legs only cycling, graded treadmill running, and combined arm cranking and leg cycling. Results of the study showed that well-trained upper body athletes attained a significantly higher…

  8. VO2max estimation from a submaximal 1-mile track jog for fit college-age individuals.

    Science.gov (United States)

    George, J D; Vehrs, P R; Allsen, P E; Fellingham, G W; Fisher, A G

    1993-03-01

    The primary purpose of this study was to develop a submaximal field test for the estimation of maximal oxygen uptake (VO2max) using a 1-mile track jog. A second purpose was to determine the accuracy of the 1.5-mile run in estimating VO2max for both male and female subjects. VO2max was measured in 149 relatively fit college students (males = 88, females = 61) 18-29 yr using a treadmill protocol (mean +/- SD; VO2max = 47.7 +/- 6.3 ml.kg-1 x min-1). Multiple regression analysis (N = 54) to estimate VO2max from the submaximal, steady-state 1-mile track jog yielded the following validation (V) model (r(adi) = 0.87, SEE = 3.0 ml.kg-1 x min-1): VO2max = 100.5 + 8.344* GENDER (0 = female; 1 = male) - 0.1636* BODY MASS (kg) - 1.438* JOG TIME (min.mile-1) - 0.1928* HEART RATE (bpm). To help ensure that a submaximal level of exertion was realized for the 1-mile track jog, elapsed jog time was restricted to > or = 8.0 min for males and > or = 9.0 min for females and exercise HR to < or = 180 bpm. Cross-validation (CV) of the 1-mile track jog comparing observed and estimated VO2max (N = 52) resulted in radj = 0.84, SEE = 3.1 ml.kg-1 x min-1. Multiple regression analysis (N = 50) to estimate VO2max from the 1.5-mile run (V:N = 49, radj = 0.90, SEE = 2.8 ml.kg-1 x min-1; CV: N = 47, radj = 0.82, SEE = 3.9 ml.kg-1 x min-1), used elapsed run time, body mass, and gender as independent variables.(ABSTRACT TRUNCATED AT 250 WORDS)

  9. Influence of simulated microgravity on the VO2 max of nontrained and trained rats

    Science.gov (United States)

    Woodman, C. R.; Monnin, K. A.; Sebastian, L. A.; Tipton, C. M.

    1993-01-01

    Head-down suspension (HDS) of rats has evolved as a useful model for the simulation of a microgravity environment. Previous HDS experiments with rats have shown an impaired capacity to perform aerobic exercise as demonstrated by reductions in maximum oxygen consumption (VO2 max), treadmill run time (RT), and mechanical efficiency (ME) of treadmill running at submaximal conditions. To determine whether endurance training (TR) before HDS would modify exercise performance, male Sprague-Dawley rats were assigned to nontrained (NT) or TR groups for 6 wk and exposed to HDS or cage control (CC) conditions for 29 days. The rats were tested for VO2 max, RT, and ME before treatment and on days 7, 14, 21, and 28. In addition, water and electrolyte excretion was measured on days 1 and 21 of the experimental period. Before HDS, the TR rats had significantly higher measures of VO2 max (15%) and RT (22%) than the NT rats. On day 28, HDS was associated with significant reductions in absolute VO2 max (ml/min) in TR (-30%) and NT (-14%) rats. Relative VO2 max (ml.min-1.kg-1) was significantly reduced in TR (-15%) but not NT rats. Similar reductions in RT occurred in TR (-37%) and NT (-35%) rats by day 28. ME was reduced 22% in both TR and NT rats after 28 days of suspension. HDS elicited diuresis, natriuresis, and kaliuresis in TR rats after 21 days but not after 24 h. In contrast, HDS-NT rats exhibited no diuretic, natriuretic, or kaliuretic responses.(ABSTRACT TRUNCATED AT 250 WORDS).

  10. Accuracy of VO2(max) prediction equations in older adults.

    Science.gov (United States)

    Peterson, Matthew J; Pieper, Carl F; Morey, Miram C

    2003-01-01

    We explored the accuracy and bias of prediction equations (ACSM and Foster) in older, deconditioned men and women. We also examined the predictors of VO2(max) to further understand which variables affect respiratory fitness in the elderly. One hundred seventy-one community dwelling, men (72.6 +/- 4.8 yr) and women (71.0 +/- 5.1 yr) screened in a clinical trial were retrospectively examined. VO2(max) was measured using a standardized protocol with gas exchange measured. Measured VO2 (max) values were compared with prediction equations via mean difference analyses, and bias was explored using Bland-Altman analyses. Regression analysis determined significant predictors of measured VO2 (max). Alpha was PVO2 (max), 21.7 +/- 4.8 and 17.3 +/- 4.0, respectively. ACSM overestimated VO2 (max) in men and women, 26.3 +/- 8.2 and 20.9 +/- 7.3, respectively. By using Bland-Altman plots, ACSM showed significant overestimation bias in more fit women (r = 0.29), whereas Foster showed no estimation bias in either gender. Significant predictors of VO2 (max) were gender, BMI, age, treadmill grade, and speed, with an equation R(2) of 0.70. A measure of current activity levels did not make it into the final model ( P= 0.0505) but is worthy of future consideration using more sensitive measures than ours. ACSM is not appropriate for use when treadmill testing older adults. We believe the Foster equation's VO2 (max) prediction accuracy is acceptable, showing no bias along a continuum of aerobic capacity.

  11. Biology of VO2 max: looking under the physiology lamp.

    Science.gov (United States)

    Lundby, C; Montero, D; Joyner, M

    2017-06-01

    In this review, we argue that several key features of maximal oxygen uptake (VO2 max) should underpin discussions about the biological and reductionist determinants of its interindividual variability: (i) training-induced increases in VO2 max are largely facilitated by expansion of red blood cell volume and an associated improvement in stroke volume, which also adapts independent of changes in red blood cell volume. These general concepts are also informed by cross-sectional studies in athletes that have very high values for VO2 max. Therefore, (ii) variations in VO2 max improvements with exercise training are also likely related to variations in these physiological determinants. (iii) All previously untrained individuals will respond to endurance exercise training in terms of improvements in VO2 max provided the stimulus exceeds a certain volume and/or intensity. Thus, genetic analysis and/or reductionist studies performed to understand or predict such variations might focus specifically on DNA variants or other molecular phenomena of relevance to these physiological pathways. © 2016 Scandinavian Physiological Society. Published by John Wiley & Sons Ltd.

  12. Submaximal treadmill test predicts VO2max in overweight children.

    Science.gov (United States)

    Nemeth, Blaise A; Carrel, Aaron L; Eickhoff, Jens; Clark, R Randall; Peterson, Susan E; Allen, David B

    2009-05-01

    To demonstrate the ability of a submaximal test to predict VO(2max) in overweight children. A total of 130 children, 11 to 14 years old, with body mass index >85 percentile for age and sex performed a submaximal walking test. VO(2max) was measured by using open circuit spirometry during a graded exercise test to volitional fatigue. An equation to predict VO(2max) was modeled by using the variables of sex, weight (kg), height (cm), heart rate (HR) after 4 minutes during the submaximal test (4minHR), HR difference (4minHR - resting HR), and submaximal treadmill speed (miles per hour [mph]) in 75% of the subjects. Validation was performed by using the remaining 25% of subjects. A total of 113 subjects achieved a maximal effort and was used in the statistical analysis. Development and validation groups were similar in all aspects. On validation, the mean square error was 241.06 with the predicted VO(2max) within 10% of the observed value in 67% of subjects. VO(2max) was accurately predicted in this cohort of overweight children by using a submaximal, treadmill-based testing protocol.

  13. Reproducibility of maximum aerobic power (VO2max among soccer players using a modified heck protocol Reprodutibilidade da potência aeróbia máxima (VO2max em jogadores de futebol utilizando o protocolo de heck modificado

    Directory of Open Access Journals (Sweden)

    Paulo Roberto Santos-Silva

    2007-01-01

    Full Text Available OBJECTIVE: To determine the degree of reproducibility of maximum oxygen consumption (VO2max among soccer players, using a modified Heck protocol. METHODS: 2 evaluations with an interval of 15 days between them were performed on 11 male soccer players. All the players were at a high performance level; they were training for an average of 10 hours per week, totaling 5 times a week. When they were evaluated, they were in the middle of the competitive season, playing 1 match per week. The soccer players were evaluated on an ergometric treadmill with velocity increments of 1.2 km.h-1 every 2 minutes and a fixed inclination of 3% during the test. VO2max was measured directly using a breath-by-breath metabolic gas analyzer. RESULTS: The maximum running speed and VO2max attained in the 2 tests were, respectively: (15.6 ± 1.1 vs. 15.7 ± 1.2 km.h-1; [P = .78] and (54.5 ± 3.9 vs. 55.2 ± 4.4 ml.kg-1.min-1; [P = .88]. There was high and significant correlation of VO2max between the 2 tests with a 15-day interval between them [r = 0.97; P OBJETIVO: Determinar o grau de reprodutibilidade do consumo máximo de oxigênio (VO2max em jogadores de futebol utilizando o protocolo de Heck modificado. MÉTODOS: Foram avaliados por duas vezes, com intervalo de 15 dias entre os testes, 11 futebolistas masculinos. Todos eram de alto nível, treinavam em média 10 horas por semana subdivididos em treinamentos físicos, técnicos, táticos e jogos competitivos, totalizando cinco vezes por semana e na fase em que foram avaliados se encontravam em pleno período competitivo realizando um jogo por semana. Os futebolistas foram avaliados em esteira ergométrica (1,2 km.h-1 a cada dois minutos e inclinação fixa durante o teste em 3%. O VO2max foi medido diretamente utilizando analisador metabólico de análise de gases expirados respiração-a-respiração. RESULTADOS: A velocidade máxima de corrida e o VO2max atingido nos dois testes foram respectivamente: (15,6 ± 1

  14. Matching of Male and Female Subjects Using VO2 Max.

    Science.gov (United States)

    Cureton, Kirk J.

    1981-01-01

    The increasing use of various VO2 max expressions as test measures is a problem because the magnitude of sex difference varies considerably with each expression. A valid match of male and female test subjects would consider physical activity history and the amount of endurance exercise done in the previous year. (Author/FG)

  15. Validity of 3 protocols for verifying VO2 max.

    Science.gov (United States)

    Kirkeberg, J M; Dalleck, L C; Kamphoff, C S; Pettitt, R W

    2011-04-01

    The verification bout has emerged as a technique for confirming 'true' VO2 max; however, validity during a single visit is unknown. We evaluated 3 different GXT durations with severe intensity verification bouts. On 3 separate days, in counterbalanced order, 12 recreational-trained men completed short (9±1 min), middle (11±1 min), and long (13±2 min) duration GXTs followed by exhaustive, sine wave verification bouts during the same visit. Intensities for verification were set at speeds equivalent to 2-stages minus end-GXT speed. No differences (pVO2 max (mL/kg/min) were observed between short (49.1), middle (48.2), and long (48.8) protocols. In addition, no differences in verification bout duration occurred between protocols (3±1 min). Validity of VO2 max was strongest for the middle duration protocol (ICC α=0.97; typical error=1 mL/kg/min; CV=2%). A small, but significantly higher HR (max) (∼1-2 bpm) was observed for the long protocol. Maximum respiratory exchange ratios were inconsistent (ICC α ranged 0.58-0.68). Our findings indicate GXT-verification bout testing during a single visit is a valid means of measuring 'true' VO2 max. The 10 min target for GXT duration was the optimum. © Georg Thieme Verlag KG Stuttgart · New York.

  16. Prediction of VO2max in Children and Adolescents Using Exercise Testing and Physical Activity Questionnaire Data.

    Science.gov (United States)

    Black, Nate E; Vehrs, Pat R; Fellingham, Gilbert W; George, James D; Hager, Ron

    2016-01-01

    The purpose of this study was to evaluate the use of a treadmill walk-jog-run exercise test previously validated in adults and physical activity questionnaire data to estimate maximum oxygen consumption (VO2max) in boys (n = 62) and girls (n = 66) aged 12 to 17 years old. Data were collected from Physical Activity Rating (PA-R) and Perceived Functional Ability (PFA) questionnaires, a walk-jog-run submaximal treadmill exercise test, and a maximal graded exercise test. Regression analysis resulted in the development of 2 models to predict VO2max. Submaximal exercise test data were used to build the following model (R2 = .73; SEE = 4.59 mL + kg(- 1) + min(- 1)): VO2max (mL + kg(- 1) + min(- 1)) = 26.890+(5.877 × Gender; 0 = female; 1 = male) - (0.782 × Body Mass Index [BMI])+(0.438 × PFA Score) +(2.712 × Treadmill Speed; mph) +(0.746 × Age) +(0.449 × PA-R Score). Maximal exercise test data were used to build the following model (R2 = .83; SEE = 3.63 mL + kg(- 1) + min(- 1)): VO2max (mL + kg(- 1) + min(- 1)) = 10.716+(1.334 × Maximal Treadmill Grade) +(5.203 × Treadmill Speed; mph) +(3.494 × Gender; 0 = female; 1 = male) - (0.413 × BMI) +(0.249 × PFA). The results of this study demonstrate, for the first time, that regression equations that use both exercise data and physical activity questionnaire data can accurately predict VO2max in youth. The submaximal and maximal exercise tests that use self-selected treadmill speeds can be used to assess cardiorespiratory fitness of youth with a wide range of fitness levels.

  17. Effect of hindlimb suspension on VO2 max and regional blood flow responses to exercise.

    Science.gov (United States)

    Overton, J M; Woodman, C R; Tipton, C M

    1989-02-01

    Male rodents were studied before and after undergoing one of three treatment conditions for 9 days: 1) cage control (n = 15, CON), 2) horizontal suspension (n = 15, HOZ), and 3) head-down suspension (n = 18, HDT). Testing included measurements of maximal O2 uptake (VO2 max) and select cardiovascular responses to graded treadmill exercise. VO2 max expressed on an absolute basis (ml/min) was significantly decreased after HOZ (-14.1 +/- 2.5%) and HDT (-14.3 +/- 2.0%), while being essentially unchanged in CON (-1.0 +/- 3.3%). Significant reductions in body weight were observed after both HOZ (-10.1 +/- 4.2 g) and HDT (-22.5 +/- 3.3 g), whereas CON animals exhibited a significant increase in weight (10.4 +/- 3.8 g). As a result, when VO2 max was normalized for body weight, all groups exhibited similar significant reductions of 6-7%. Although no differences in heart rate and blood pressure response to graded exercise were observed, the HDT group exhibited greater increases in mesenteric resistance at the same absolute exercise intensity. Furthermore, both suspended groups had higher iliac resistance values during exercise at similar relative exercise conditions, suggesting that muscle blood flow during treadmill running may have been reduced after suspension. In general, the decrements associated with the HOZ and HDT conditions were similar. It was concluded that reduction in exercise capacity and altered cardiovascular responses to exercise observed after 6-9 days of suspension were attributable to a combination of hypokinesia, lack of hindlimb weight bearing, or restraint, rather than to hydrostatic influences associated with HDT.

  18. Comparison of Blood Cholesterol Profiles Before and After The Measurements of Maximum Aerobic Capacity (VO2max

    Directory of Open Access Journals (Sweden)

    Ar Rasyid Shadiqin

    2013-11-01

    Full Text Available This study is aimed to compare the blood cholesterol profile, before and after the measurement of maximum aerobic capacity (VO2max in the students of Jurusan Pendidikan Olahraga dan Kesehatan (JPOK pada Fakultas Keguruan dan Ilmu Pendidikan (FKIP Universitas Lambung Mangkurat Banjarmasin.Variables in this study consist of lipid profiles, including total cholesterol, high density lipoprotein (HDL, low density lipoprotein (LDL, triglyceride (TG and Maximum Aerobic Capacity (VO2max. The concept of VO2max according to Kent(1994:268: “maximum oxygen volume consumed per minute to show total work capacity, or volume per minute relative to body weight (ml/kg.min”. Operationally, VO2max referred in this study is the maximum volume of oxygen that can be consumed per minute, as measured at progressive run (Bleep Test.The method used in this study is pre-experimental with one group pretest-posttest design. This design implies that a group of subjects are treated for a specific period and the measurements are taken both pre and post.The results: There are changes in blood cholesterol profile after the measurement of maximum oxygen capacity (VO2max, shown by significant decrease of total cholesterol variable, increased HDL, and decreased LDL. Changes in triglyceride variable showed no significant decrease despite the statistic differences. Specific HDL sub-class increasing after exercise is a constructive lipoprotein sub-class whereas LDL is destructive lipoproteins sub-class that might damage the body. Therefore, an increase in HDL and decrease in LDL found in this study appears to be advantageous and consequently might alter the risk of coronary heart disease.

  19. Monitoring changes in VO2max via the Polar FT40 in female collegiate soccer players.

    Science.gov (United States)

    Esco, Michael R; Snarr, Ronald L; Williford, Hank N

    2014-01-01

    This study was conducted to determine if the Polar FT40 could accurately track changes in maximal oxygen consumption (VO2max) in a group of female soccer players. Predicted VO2max (pVO2max) via the Polar FT40 and observed VO2max (aVO2max) from a maximal exercise test on a treadmill were determined for members of a collegiate soccer team (n = 20) before and following an 8-week endurance training protocol. Predicted (VO2max and aVO2max measures were compared at baseline and within 1 week post-training. Change values (i.e., the difference between pre to post) for each variable were also determined and compared. There was a significant difference in aVO2max (pre = 43.6 ± 2.4 ml · kg · min(-1), post = 46.2 ± 2.4 ml · kg · min(-1), P < 0.001) and pVO2max (pre = 47.3 ± 5.3 ml · kg · min(-1), post = 49.7 ± 6.2 ml · kg · min(-1), P = 0.009) following training. However, predicted values were significantly greater at each time point compared to observed values (P < 0.001 at pre and P = 0.008 at post). Furthermore, there was a weak correlation between the change in aVO2max and the change in pVO2max (r = 0.18, P = 0.45). The Polar FT40 does not appear to be a valid method for predicting changes in individual VO2max following 8 weeks of endurance training in female collegiate soccer players.

  20. PELATIHAN LARI SIRKUIT 2 X 10 MENIT DAN PELATIHAN LARI KONTINYU 2 X 10 MENIT DAPAT MENINGKATKAN VO2 MAX TAEKWONDOIN PUTRA KABUPATEN MANGGARAI - NTT

    Directory of Open Access Journals (Sweden)

    Regina Sesilia Noy

    2014-08-01

    Full Text Available VO2 max is very important in everyday life, so as to facilitate any physicalactivity, specially for athletes in order to achieve maximum performance. In aneffort to increase VO2 max training should be carried out regularly, measured andplanned. This study aims to determine the increase in VO2 max through circuittraining run and run continuously. The sample is taekwondoin son Manggarai-NTTwith an average age of 15 years. This study is an experimental study with the studydesign used was Randomized Pre and Post Test Group desigen. With a totalsample of 7 people in each group. Samples were randomly selected. Treatmentgroup 1 (KP1 given training run circuit 2 x 10 minute and Treatment Group 2(KP2 are given continuous training run 2 x 10 minute. Training carried out for 6weeks with a frequency of four times a week starting at 17:00 to 18:00 pm locatedat Frans Sales Lega Airport Manggarai-NTT. The analysis showed an increase inVO2 max was significantly (p <0.05 against both groups fled. In both groups thecircuit run by Pulse Oxymeter and Norma Cooper an increase in VO2 max with p<0.05, as well as a continuous run either by Pulse Oxymeter and Norma Cooperwith an increase in VO2 max value of p <0.05. The results of this analysis meansthat either the training or circuit training run run continuously to improve VO2max. Based on a comparison of test data by an independent test after training inboth groups either by Pulse Oxymeter and Norma Cooper in get p values > 0.05, orthere is no significant difference. Based on these results it can be concluded thatthe run circuit training and continuous training run together can increase VO2 maxand there was no significant difference. The results of this study are expected toincrease the knowledge of coaches, teachers and taekwondoin to perform trainingon a regular basis and are also expected to do similar research that examines VO2max with different training.

  1. The Effect of Aging on Relationships between Lean Body Mass and VO2max in Rowers.

    Science.gov (United States)

    Kim, Chul-Ho; Wheatley, Courtney M; Behnia, Mehrdad; Johnson, Bruce D

    2016-01-01

    Aging is associated with a fall in maximal aerobic capacity as well as with a decline in lean body mass. The purpose of the study was to investigate the influence of aging on the relationship between aerobic capacity and lean body mass in subjects that chronically train both their upper and lower bodies. Eleven older rowers (58±5 yrs) and 11 younger rowers (27±4 yrs) participated in the study. Prior to the VO2max testing, subjects underwent a dual energy X-ray absorptiometry scan to estimate total lean body mass. Subsequently, VO2max was quantified during a maximal exercise test on a rowing ergometer as well as a semi-recumbent cycle ergometer. The test protocol included a pre-exercise stage followed by incremental exercise until VO2max was reached. The order of exercise modes was randomized and there was a wash-out period between the two tests. Oxygen uptake was obtained via a breath-by-breath metabolic cart (Vmax™ Encore, San Diego, CA). Rowing VO2max was higher than cycling VO2max in both groups (pVO2max from cycling to rowing (pVO2max for both groups (pVO2max between groups disappeared (p>0.05), however, older subjects still demonstrated a lower rowing VO2max relative to younger subjects (pVO2max obtained, however, it appears that VO2max in older subjects may be less influenced by muscle mass than in younger subjects.

  2. A longitudinal assessment of change in VO2max and maximal heart rate in master athletes.

    Science.gov (United States)

    Hawkins, S A; Marcell, T J; Victoria Jaque, S; Wiswell, R A

    2001-10-01

    The purpose of this study was to determine the longitudinal change in VO2max and HRmax in male and female master endurance runners and to compare these changes based upon gender, age, and change in training volume. Eighty-six male (53.9 +/- 1.1 yr) and 49 female (49.1 +/- 1.2 yr) master endurance runners were tested an average of 8.5 yr apart. Subjects were grouped by age at first visit, change in VO2max, and change in training volume. Measurements included body composition by hydrostatic weighing, maximal exercise testing on a treadmill, and training history by questionnaire. Data were analyzed by ANOVA and multiple regression. VO2max and HRmax declined significantly regardless of gender or age group (P VO2max by age group ranged from -1% to -4.6% per year for men and -0.5% to 2.4% per year for women. Men with the greatest loss in VO2max had the greatest loss in LBM (-2.8 +/- 0.7 kg), whereas women with the greatest loss in VO2max demonstrated the greatest change in training volume (-24.1 +/- 3.0 km.wk-1). Additionally, women with the greatest loss in VO2max (-9.6 +/- 2.6 mL.kg-1.min-1) did not replace estrogen after menopause independent of age. HRmax change did not differ by VO2max change or training volume change in either gender. In conclusion, these data suggest that VO2max declines in male and female master athletes at a rate similar to or greater than that expected in sedentary older adults. Additionally, these data suggest that maintenance of LBM and VO2max were associated in men, whereas in women, estrogen replacement and maintenance of training volume were associated with maintained VO2max.

  3. A Study of VO2 Max and Body Fat Percentage in Female Athletes

    Science.gov (United States)

    Bute, Smita S; Deshmukh, P.R

    2014-01-01

    Introduction: Aerobic capacity of athletes is an important element of success in sports achievements. It is generally considered the best indicator of cardio respiratory endurance and athletic fitness. Body fat percentage affects VO2 max and thus the cardiovascular status of the athletes. The present study was undertaken to assess the VO2 max and body fat percentage in athletes. The secondary objective of the study was to study the relationship between VO2 max and body fat percentage. Materials and Methods: Twenty five female athletes of age group 17-22years were selected for the study. VO2 max was determined by Queen’s college step test and body fat percentage by skin fold calipers. The VO2 max and body fat percentage were determined in non athletes of same age group for comparison. The statistical analysis was done by Student’s t-test and Pearson correlation test. Observation and Results: The mean VO2 max in athletic group was 39.62 ± 2.80 ml/kg/min. In non-athletic group, VO2 max was 23.54 ± 3.26 ml/kg/min. The mean body fat percentage in athletes was 24.11 ± 1.83% and in non-athletes it was 29.31 ± 3.86%.The difference in VO2 max and body fat percentage was statistically significant in our study. The VO2 max and body fat percentage in both the groups showed negative correlation by Pearson test but, was not statistically significant. Conclusion: The present study showed a statistically significant higher VO2 max in female athletes. The study showed a negative correlation between VO2 max and body fat percentage but was not statistically significant. PMID:25653935

  4. Waist circumference and VO2max are associated with metabolic and hemostatic risk in premenopausal nurses

    NARCIS (Netherlands)

    Elich, H; Riese, H; De Geus, EJC

    In 21 nurses (34.4+/-3.9 yr), VO2max, physical activity, body composition and lifestyle parameters were measured to determine which of these characteristics are related to metabolic and hemostatic risk for cardiovascular disease. Physical activity was assessed with the 7-day recall interview VO2max

  5. Effect of Toe Clips During Bicycle Ergometry on VO2 max.

    Science.gov (United States)

    Moffat, Roger S.; Sparling, Phillip B.

    1985-01-01

    Eight men participated in three randomized maximal oxygen uptake tests to investigate the hypothesis that the use of toe clips on bicycle ergometers produced a higher VO2 max. No significant difference in mean VO2 max or performance time was observed. (Author/MT)

  6. A new non-exercise-based Vo2max prediction equation for aerobically trained men.

    Science.gov (United States)

    Malek, Moh H; Housh, Terry J; Berger, Dale E; Coburn, Jared W; Beck, Travis W

    2005-08-01

    The purposes of the present study were to (a) modify previously published Vo(2)max equations using the constant error (CE = mean difference between actual and predicted Vo(2)max) values from Malek et al. (28); (b) cross-validate the modified equations to determine their accuracy for estimating Vo(2)max in aerobically trained men; (c) derive a new non- exercise-based equation for estimating Vo(2)max in aerobically trained men if the modified equations are not found to be accurate; and (d) cross-validate the new Vo(2)max equation using the predicted residual sum of squares (PRESS) statistic and an independent sample of aerobically trained men. One hundred and fifty-two aerobically trained men (Vo(2)max mean +/- SD = 4,154 +/- 629 ml.min(-1)) performed a maximal incremental test on a cycle ergometer to determine actual Vo(2)max. An aerobically trained man was defined as someone who had participated in continuous aerobic exercise 3 or more sessions per week for a minimum of 1 hour per session for at least the past 18 months. Nine previously published Vo(2)max equations were modified for use with aerobically trained men. The predicted Vo(2)max values from the 9 modified equations were compared to actual Vo(2)max by examining the CE, standard error of estimate (SEE), validity coefficient (r), and total error (TE). Cross-validation of the modified non-exercise-based equations on a random subsample of 50 subjects resulted in a %TE > or = 13% of the mean of actual Vo(2)max. Therefore, the following non-exercise-based Vo(2)max equation was derived from a random subsample of 112 subjects: Vo(2)max (ml.min(-1)) = 27.387(weight in kg) + 26.634(height in cm) - 27.572(age in years) + 26.161(h.wk(-1) of training) + 114.904(intensity of training using the Borg 6-20 scale) + 506.752(natural log of years of training) - 4,609.791 (R = 0.82, R(2) adjusted = 0.65, and SEE = 378 ml.min(-1)). Cross-validation of this equation on the remaining sample of 40 subjects resulted in a %TE of 10

  7. High-intensity interval training every second week maintains VO2max in soccer players during off-season.

    Science.gov (United States)

    Slettaløkken, Gunnar; Rønnestad, Bent R

    2014-07-01

    Reduced endurance training among semiprofessional soccer players during off-season may have negative effect on game performance during the competition season. This negative effect can be prevented by adding high-intensity interval training (HIT) to normal activity. In this study, we want to compare 2 different frequencies of HIT (5 bouts of 4 minutes on 87-97% peak heart rate) session on maintenance of aerobic fitness among semiprofessional soccer players during a 6-week off-season period. Seventeen male players at second and third highest soccer division in Norway participated. The subjects were randomized into 1 HIT session every second week (HIT 0.5) or 1 HIT session per week (HIT 1). All participants performed a 20-m shuttle run test and a maximal oxygen uptake (VO2max) test on treadmill before and after the training intervention. VO2max (HIT 0.5, 63.4 ± 5.9 ml·kg-1·min-1; HIT 1, 65.6 ± 2.1 ml·kg-1·min-1) and 20-m shuttle run performance (HIT 0.5, 2335 ± 390 m, HIT 1, 2531 ± 106 m) were not different between the groups before the training intervention. VO2max was maintained after the training intervention in both HIT 0.5 and HIT 1 (64.0 ± 5.9 ml·kg-1·min-1 and 64.3 ± 1.3 ml·kg-1·min-1, respectively). There was a reduction in distance covered during the 20-m shuttle run test in HIT 1 and when groups were pooled (-7.9 ± 5.7% and -6.4 ± 7.9%, respectively, p ≤ 0.05). In conclusion, HIT 1 did not maintain VO2max better than HIT 0.5 when added to normal off-season activity. However, performance in 20-m shuttle run, which is a more soccer-specific fitness test than VO2max test, was slightly reduced when both groups was pooled.

  8. Prediction of VO2max from a new field test based on portable indirect calorimetry.

    Science.gov (United States)

    Flouris, Andreas D; Metsios, Giorgos S; Famisis, Konstantinos; Geladas, Nikos; Koutedakis, Yiannis

    2010-01-01

    We assessed the validity and reliability of the new 15m square shuttle run test (SST) for predicting laboratory treadmill test (TT) maximal oxygen uptake (VO(2 max)) compared to the 20 m multistage shuttle run test (MST) in 45 adult males. Thirty participants performed a TT and a SST once to develop a VO( 2max) prediction model. The remaining 15 participants performed the TT and MST once and the SST twice for cross-validation purposes. Throughout testing V O(2max) was determined via portable indirect calorimetry while blood lactate concentration was assessed at the fifth recovery minute. Comparisons of TT V O(2 max) (51.3+/-3.1 ml kg(-1)min(-1)) with SST measured (51.2+/-3.2 ml kg(-1)min(-1)) and predicted (50.9+/-3.3 ml kg(-1)min(-1)) V O(2 max) showed no differences while TT blood lactate was higher compared to SST (10.3+/-1.7 mmol vs. 9.7+/-1.7 mmol, respectively). In contrast, MST measured (53.4+/-3.5 ml kg(-1)min(-1)) and predicted (57.0+/-4.5 ml kg(-1)min(-1)) V O(2 max) and blood lactate (11.2+/-2.0 mmol) were significantly higher compared to TT. No test-retest differences were detected for SST measured and predicted V O(2 max) and blood lactate. It is concluded that the SST is a highly valid and reliable predictive test for V O(2 max). Copyright (c) 2009 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  9. Daily pattern of %VO2max and heart rates in normal and undernourished school children.

    Science.gov (United States)

    Spurr, G B; Reina, J C

    1990-10-01

    The pattern of usage of the VO2max, expressed as %VO2max during ordinary school days, with minute-by-minute heart rate recording, was studied in 106 boys and 83 girls, 6-16 yr of age divided into three age groups (6-8, 10-12, and 14-16 yr), living under economically deprived conditions in Colombia and classified as nutritionally normal or marginally malnourished. In a 12-h period, the 12 groups of children spent, on the average, 7-10 h at less than 30% VO2max, 1.5-4 h at 30-50% VO2max, and an accumulated time of 20-60 min above 50% VO2max. The latter occurred in short bursts rather than during sustained periods. There was a statistically significant but small decrease (approximately -3%) in the average 12 h %VO2max with age but no effects of sex or nutritional status. The overall average was about 25% VO2max in all groups. The data may suggest the existence of the regulation of physical activity to some level easily sustainable for long periods. Expressing the data as 30 min averages during 5 h of school and 5 h of free-time activity allows for the possibility of seeing group differences during shorter periods of time. This may prove useful in exercise training programs and studies of effort in the workplace.

  10. VO2 max is associated with ACE genotype in postmenopausal women.

    Science.gov (United States)

    Hagberg, J M; Ferrell, R E; McCole, S D; Wilund, K R; Moore, G E

    1998-11-01

    Relationships have frequently been found between angiotensin-converting enzyme (ACE) genotype and various pathological and physiological cardiovascular outcomes and functions. Thus we sought to determine whether ACE genotype affected maximal O2 consumption (VO2 max) and maximal exercise hemodynamics in postmenopausal women with different habitual physical activity levels. Age, body composition, and habitual physical activity levels did not differ among ACE genotype groups. However, ACE insertion/insertion (II) genotype carriers had a 6.3 ml . kg-1 . min-1 higher VO2 max (P VO2 max (P VO2 max than the DD genotype group, but the difference was not significant. ACE genotype accounted for 12% of the variation in VO2 max among women after accounting for the effect of habitual physical activity levels. The entire difference in VO2 max among ACE genotype groups was the result of differences in maximal arteriovenous O2 difference (a-vDO2). ACE genotype accounted for 17% of the variation in maximal a-vDO2 in these women. Maximal cardiac output index did not differ whatsoever among ACE genotype groups. Thus it appears that ACE genotype accounts for a significant portion of the interindividual differences in VO2 max among these women. However, this difference is the result of genotype-dependent differences in maximal a-vDO2 and not of maximal stroke volume and maximal cardiac output.

  11. .VO2max is not altered by self-pacing during incremental exercise.

    Science.gov (United States)

    Chidnok, Weerapong; Dimenna, Fred J; Bailey, Stephen J; Burnley, Mark; Wilkerson, Daryl P; Vanhatalo, Anni; Jones, Andrew M

    2013-02-01

    We tested the hypothesis that incremental cycling to exhaustion that is paced using clamps of the rating of perceived exertion (RPE) elicits higher .VO2max values compared to a conventional ramp incremental protocol when test duration is matched. Seven males completed three incremental tests to exhaustion to measure .VO2max. The incremental protocols were of similar duration and included: a ramp test at 30 W min(-1) with constant cadence (RAMP1); a ramp test at 30 W min(-1) with cadence free to fluctuate according to subject preference (RAMP2); and a self-paced incremental test in which the power output was selected by the subject according to prescribed increments in RPE (SPT). The subjects also completed a .VO2max 'verification' test at a fixed high-intensity power output and a 3-min all-out test. No difference was found for .VO2max between the incremental protocols (RAMP1 = 4.33 ± 0.60 L min(-1); RAMP2 = 4.31 ± 0.62 L min(-1); SPT = 4.36 ± 0.59 L min(-1); P > 0.05) nor between the incremental protocols and the peak.VO2max measured during the 3-min all-out test (4.33 ± 0.68 L min(-1)) or the .VO2max measured in the verification test (4.32 ± 0.69 L min(-1)). The integrated electromyogram, blood lactate concentration, heart rate and minute ventilation at exhaustion were not different (P > 0.05) between the incremental protocols. In conclusion, when test duration is matched, SPT does not elicit a higher .VO2max compared to conventional incremental protocols. The striking similarity of .VO2max measured across an array of exercise protocols indicates that there are physiological limits to the attainment of .VO2max that cannot be exceeded by self-pacing.

  12. Validation of a new method for estimating VO2max based on VO2 reserve.

    Science.gov (United States)

    Swain, David P; Parrott, James A; Bennett, Anna R; Branch, J David; Dowling, Elizabeth A

    2004-08-01

    The American College of Sports Medicine's (ACSM) preferred method for estimating maximal oxygen consumption (VO2max) has been shown to overestimate VO2max, possibly due to the short length of the cycle ergometry stages. This study validates a new method that uses a final 6-min stage and that estimates VO2max from the relationship between heart rate reserve (HRR) and VO2 reserve. A cycle ergometry protocol was designed to elicit 65-75% HRR in the fifth and sixth minutes of the final stage. Maximal workload was estimated by dividing the workload of the final stage by %HRR. VO2max was then estimated using the ACSM metabolic equation for cycling. After the 6-min stage was completed, an incremental test to maximal effort was used to measure actual VO2max. Forty-nine subjects completed a pilot study using one protocol to reach the 6-min stage, and 50 additional subjects completed a modified protocol. The pilot study obtained a valid estimate of VO2max (r = 0.91, SEE = 3.4 mL x min(-1) x kg-1) with no over- or underestimation (mean estimated VO2max = 35.3 mL x min(-1) x kg(-1), mean measured VO2max = 36.1 mL x min(-1) x kg(-1)), but the average %HRR achieved in the 6-min stage was 78%, with several subjects attaining heart rates considered too high for submaximal fitness testing. The second study also obtained a valid estimate of VO2max (r = 0.89, SEE = 4.0 mL x min(-1) x kg(-1)) with no over- or underestimation (mean estimated VO2max = 36.7 mL x min(-1) x kg(-1), mean measured VO2max = 36.9 mL x min(-1) x kg(-1), and the average %HRR achieved in the 6-min stage was 64%. A new method for estimating VO2max from submaximal cycling based on VO2 reserve has been found to be valid and more accurate than previous methods.

  13. Improved VO2max and time trial performance with more high aerobic intensity interval training and reduced training volume: a case study on an elite national cyclist.

    Science.gov (United States)

    Støren, Øyvind; Bratland-Sanda, Solfrid; Haave, Marius; Helgerud, Jan

    2012-10-01

    The present study investigated to what extent more high aerobic intensity interval training (HAIT) and reduced training volume would influence maximal oxygen uptake (VO2max) and time trial (TT) performance in an elite national cyclist in the preseason period. The cyclist was tested for VO2max, cycling economy (C(c)), and TT performance on an ergometer cycle during 1 year. Training was continuously logged using heart rate monitor during the entire period. Total monthly training volume was reduced in the 2011 preseason compared with the 2010 preseason, and 2 HAIT blocks (14 sessions in 9 days and 15 sessions in 10 days) were performed as running. Between the HAIT blocks, 3 HAIT sessions per week were performed as cycling. From November 2010 to February 2011, the cyclist reduced total average monthly training volume by 18% and cycling training volume by 60%. The amount of training at 90-95% HRpeak increased by 41%. VO2max increased by 10.3% on ergometer cycle. TT performance improved by 14.9%. C(c) did not change. In conclusion, preseason reduced total training volume but increased amount of HAIT improved VO2max and TT performance without any changes in C(c). These improvements on cycling appeared despite that the HAIT blocks were performed as running. Reduced training time, and training transfer from running into improved cycling form, may be beneficial for cyclists living in cold climate areas.

  14. Effects of erythrocyte infusion on VO2max at high altitude

    DEFF Research Database (Denmark)

    Young, Jette Feveile; Sawka, M N; Muza, S R

    1996-01-01

    group received only saline. The VO2max of erythrocyte-infused [54 +/- 1 (SE) ml.kg-1.min-1] and control subjects (52 +/- 2 ml.kg-1.min-1) did not differ at SL before infusion. The decrement in VO2max on HA1 did not differ between groups, averaging 26% overall, despite higher (P arterial...... hematocrit, hemoglobin concentration, and arterial O2 content in the erythrocyte-infused subjects. By HA9, there were no longer any differences in hematocrit, hemoglobin concentration, or arterial O2 content between groups. No change in VO2max occurred between HA1 and HA9 for either group. Thus, despite...... increasing arterial O2-carrying capacity, autologous erythrocyte infusion did not ameliorate the decrement in VO2max at 4,300-m altitude....

  15. Patterns of Senescence in Human Cardiovascular Fitness: VO2max in Subsistence and Industrialized Populations

    Science.gov (United States)

    Pisor, Anne C.; Gurven, Michael; Blackwell, Aaron D.; Kaplan, Hillard; Yetish, Gandhi

    2014-01-01

    Objectives This study explores whether cardiovascular fitness levels and senescent decline are similar in the Tsimane of Bolivia and Canadians, as well as other subsistence and industrialized populations. Among Tsimane, we examine whether morbidity predicts lower levels and faster decline of cardiovascular fitness, or whether their lifestyle (e.g., high physical activity) promotes high levels and slow decline. Alternatively, high activity levels and morbidity might counterbalance such that Tsimane fitness levels and decline are similar to those in industrialized populations. Methods Maximal oxygen uptake (VO2max) was estimated using a step test heart rate method for 701 participants. We compared these estimates to the Canadian Health Measures Survey and previous studies in industrialized and subsistence populations. We evaluated whether health indicators and proxies for market integration were associated with VO2max levels and rate of decline for the Tsimane. Results The Tsimane have significantly higher levels of VO2max and slower rates of decline than Canadians; initial evidence suggests differences in VO2max levels between other subsistence and industrialized populations. Low hemoglobin predicts low VO2max for Tsimane women while helminth infection predicts high VO2max for Tsimane men, though results might be specific to the VO2max scaling parameter used. No variables tested interact with age to moderate decline. Conclusions The Tsimane demonstrate higher levels of cardiovascular fitness than industrialized populations, but levels similar to other subsistence populations. The high VO2max of Tsimane is consistent with their high physical activity and few indicators of cardiovascular disease, measured in previous studies. PMID:24022886

  16. A theoretical analysis of factors determining VO2 MAX at sea level and altitude.

    Science.gov (United States)

    Wagner, P D

    1996-12-01

    When maximal VO2 (VO2 MAX) is limited by O2 supply, it is generally thought that cardiac output (QT) is mostly responsible, but other O2 transport conductances [ventilation (VA); [Hb]; pulmonary (DLO2) and muscle (DMO2) diffusion capacities] may also influence VO2 MAX. A numerical analysis interactively linking the lungs, circulation and muscles was designed to compare the influences of each conductance component on VO2 MAX at three altitudes: PB = 760, 464 and 253 Torr. For any given set of conductances the analysis simultaneously solved six equations for alveolar, arterial, and venous PO2 and PcO2. The equations represent pulmonary mass balance, pulmonary diffusion, and muscle diffusion for both gases. At PB = 760, [Hb], DLO2 and DMO2 were as influential as QT in limiting VO2 MAX. With increasing altitude, the influence of QT and [Hb] fell while that of VA, DLO2 and DMO2 progressively increased until at PB = 253, VO2 MAX was independent of QT and [Hb]. Neither the fall in maximal QT nor rise in [Hb] with chronic hypoxia therefore appear to affect VO2 MAX. However, high values of ventilation, DLO2 and DMO2 appear to be advantageous for exercise at altitude.

  17. Inverse relationship between VO2max and economy/efficiency in world-class cyclists.

    Science.gov (United States)

    Lucía, Alejandro; Hoyos, Jesus; Pérez, Margarita; Santalla, Alfredo; Chicharro, José L

    2002-12-01

    To determine the relationship that exists between VO2max and cycling economy/efficiency during intense, submaximal exercise in world-class road professional cyclists. METHODS Each of 11 male cyclists (26+/-1 yr (mean +/- SEM); VO2max: 72.0 +/- 1.8 mL x kg(-1) x min(-1)) performed: 1) a ramp test for O2max determination and 2) a constant-load test of 20-min duration at the power output eliciting 80% of subjects' VO2max during the previous ramp test (mean power output of 385 +/- 7 W). Cycling economy (CE) and gross mechanical efficiency (GE) were calculated during the constant-load tests. CE and GE averaged 85.2 +/- 2.3 W x L(-1) x min(-1) and 24.5 +/- 0.7%, respectively. An inverse, significant correlation was found between 1) VO2max (mL x kg(-0.32) x min(-1)) and both CE (r = -0.71; P = 0.01) and GE (-0.72; P = 0.01), and 2) VO2max (mL x kg(-1) x min(-1)) and both CE (r = -0.65; P = 0.03) and GE (-0.64; P = 0.03). A high CE/GE seems to compensate for a relatively low VO2max in professional cyclists.

  18. Reliability of treadmill measures and criteria to determine VO2max in prepubertal girls.

    Science.gov (United States)

    Figueroa-Colon, R; Hunter, G R; Mayo, M S; Aldridge, R A; Goran, M I; Weinsier, R L

    2000-04-01

    The main objective of this study was to determine the reliability of measuring treadmill exercise economy (VO2submax) and the maximal oxygen uptake (VO2max) in prepubertal girls tested twice, 6 wk apart. We also wanted to examine the percentage of young girls who were able to reach the criteria for achieving VO2max and to describe methods that would allow a high proportion of young children to achieve criteria for reaching a true VO2max. We studied 61 normal-weight, prepubertal girls with a mean (+/- SD) age 7.3+/-1.3 yr (range 4.8 to 10.3 yr). VO2submax was determined while walking for 4 min at 2.5 mph with 0% grade. VO2max was measured during a progressive, all-out, continuous treadmill test using standardized procedures and criteria. Heart rate (HR) was measured using a Polar monitor. Respiratory rate (RR), respiratory exchange ratio (RER), ventilation (V), and VO2 were measured using a Sensormedics metabolic monitor. There were no significant differences between visits I and 2 in mean HR, RR, RER, V, VO2submax (421 vs 422 mL x min(-1), respectively), and VO2max (1036 vs 1049 mL x min(-1), respectively). Intra-individual coefficients of variation (CV) between visits 1 and 2 for submaximal tests were: HR = 5.1%, RR = 12.4%, RER = 7.2%, V = 12.5%, and VO2 = 12.4%. Intra-individual CVs for the maximum tests were: HRmax = 2.1%, RRmax = 10.8%, RERmax = 5.3%, Vmax = 11.7%, and VO2max = 7.5%. A high proportion of the girls reached criteria for VO2max [RER> 1.00, HR>85% of age predicted maximum, and plateauing of VO2max] in both visits: 99% reached one of three criteria, 92% reached two of three criteria, and 70% reached all three criteria. Twenty girls [mean age 7.2+/-1.2 yr] reached at least two criteria in both visits, whereas 32 girls [mean (+/- SD) age 8.6+/-1.0 yr] reached three criteria in both visits. Exercise measurements using treadmill testing were reliable in healthy, normal-weight, prepubertal girls. Older girls when compared to the younger girls were able

  19. VO2max trainability and high intensity interval training in humans: a meta-analysis.

    Science.gov (United States)

    Bacon, Andrew P; Carter, Rickey E; Ogle, Eric A; Joyner, Michael J

    2013-01-01

    Endurance exercise training studies frequently show modest changes in VO2max with training and very limited responses in some subjects. By contrast, studies using interval training (IT) or combined IT and continuous training (CT) have reported mean increases in VO2max of up to ~1.0 L · min(-1). This raises questions about the role of exercise intensity and the trainability of VO2max. To address this topic we analyzed IT and IT/CT studies published in English from 1965-2012. Inclusion criteria were: 1)≥ 3 healthy sedentary/recreationally active humans training duration 6-13 weeks, 3) ≥ 3 days/week, 4) ≥ 10 minutes of high intensity work, 5) ≥ 1:1 work/rest ratio, and 6) results reported as mean ± SD or SE, ranges of change, or individual data. Due to heterogeneity (I(2) value of 70), statistical synthesis of the data used a random effects model. The summary statistic of interest was the change in VO2max. A total of 334 subjects (120 women) from 37 studies were identified. Participants were grouped into 40 distinct training groups, so the unit of analysis was 40 rather than 37. An increase in VO2max of 0.51 L · min(-1) (95% CI: 0.43 to 0.60 L · min(-1)) was observed. A subset of 9 studies, with 72 subjects, that featured longer intervals showed even larger (~0.8-0.9 L · min(-1)) changes in VO2max with evidence of a marked response in all subjects. These results suggest that ideas about trainability and VO2max should be further evaluated with standardized IT or IT/CT training programs.

  20. VO2max trainability and high intensity interval training in humans: a meta-analysis.

    Directory of Open Access Journals (Sweden)

    Andrew P Bacon

    Full Text Available Endurance exercise training studies frequently show modest changes in VO2max with training and very limited responses in some subjects. By contrast, studies using interval training (IT or combined IT and continuous training (CT have reported mean increases in VO2max of up to ~1.0 L · min(-1. This raises questions about the role of exercise intensity and the trainability of VO2max. To address this topic we analyzed IT and IT/CT studies published in English from 1965-2012. Inclusion criteria were: 1≥ 3 healthy sedentary/recreationally active humans <45 yrs old, 2 training duration 6-13 weeks, 3 ≥ 3 days/week, 4 ≥ 10 minutes of high intensity work, 5 ≥ 1:1 work/rest ratio, and 6 results reported as mean ± SD or SE, ranges of change, or individual data. Due to heterogeneity (I(2 value of 70, statistical synthesis of the data used a random effects model. The summary statistic of interest was the change in VO2max. A total of 334 subjects (120 women from 37 studies were identified. Participants were grouped into 40 distinct training groups, so the unit of analysis was 40 rather than 37. An increase in VO2max of 0.51 L · min(-1 (95% CI: 0.43 to 0.60 L · min(-1 was observed. A subset of 9 studies, with 72 subjects, that featured longer intervals showed even larger (~0.8-0.9 L · min(-1 changes in VO2max with evidence of a marked response in all subjects. These results suggest that ideas about trainability and VO2max should be further evaluated with standardized IT or IT/CT training programs.

  1. Comparison of the IPAQ-A and actigraph in relation to VO2max among European adolescents: the HELENA study.

    Science.gov (United States)

    Ottevaere, Charlene; Huybrechts, Inge; De Bourdeaudhuij, Ilse; Sjöström, Michael; Ruiz, Jonatan R; Ortega, Francisco B; Hagströmer, Maria; Widhalm, Kurt; Molnár, Dénes; Moreno, Luis A; Beghin, Laurent; Kafatos, Anthony; Polito, Angela; Manios, Yannis; Mártinez-Gómez, David; De Henauw, Stefaan

    2011-07-01

    The purpose was to compare data obtained from a modified, long, self-administered version of the International Physical Activity Questionnaire (IPAQ-A) with objective data obtained in parallel from Actigraph accelerometers, and VO(2)max in adolescents. The study comprised a total of 2018 adolescents (46% male) from ten European cities participating in the HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) study. Physical activity was assessed over seven consecutive days by accelerometry and expressed as min/day of moderate, vigorous, and moderate to vigorous (MVPA) physical activity (PA). PA was also assessed with the IPAQ-A. VO(2)max was estimated from a 20-m shuttle run test. Poor to fair correlations between the two methodologies were found for the whole study sample and when stratified by age and gender (r(s) = 0.08-0.26, p < 0.01). On average, the self-reported time spent in moderate PA was higher compared to the time measured with the accelerometer, while the differences between both instruments were less clear for vigorous intensity. Adolescents reporting high levels of PA (3rd tertile IPAQ-A) also showed higher levels of PA (accelerometers) in all the study variables (moderate, vigorous and MVPA), compared to adolescents reporting low PA (1st tertile IPAQ-A) (all p < 0.001). Both methods were moderately correlated with estimated VO(2)max. Within the HELENA-study, the IPAQ-A showed the modest comparability with the accelerometer data for assessing PA in each intensity level and was the highest for vigorous intensity. Both instruments are able to detect the adolescents with the highest cardio respiratory fitness, which are the most active adolescents. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

  2. Comparison of intensities and rest periods for VO2max verification testing procedures.

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    Nolan, P B; Beaven, M L; Dalleck, L

    2014-11-01

    We sought to determine the incidence of 'true' VO2max confirmation with the verification procedure across different protocols. 12 active participants (men n=6, women n=6) performed in random order 4 different maximal graded exercises tests (GXT) and verification bout protocols on 4 separate days. Conditions for the rest period and verification bout intensity were: A - 105% intensity, 20 min rest; B - 105% intensity, 60 min rest; C - 115% intensity, 20 min rest; D - 115% intensity, 60 min rest. VO2max confirmation (difference between peak VO2 GXT and verification trialVO2max confirmation across all exercise test conditions (intensity effect within recovery 20 min (χ(2) (1)=4.800, pVO2max confirmation with different rest periods. We recommend the use of 105% of the maximal GXT workload and 20 min rest periods when using verification trials to confirm VO2max in normally active populations. © Georg Thieme Verlag KG Stuttgart · New York.

  3. Verification Testing to Confirm VO2max in Altitude-Residing, Endurance-Trained Runners.

    Science.gov (United States)

    Weatherwax, R M; Richardson, T B; Beltz, N M; Nolan, P B; Dalleck, L

    2016-06-01

    We sought to explore the utility of the verification trial to confirm individual attainment of 'true' VO2max in altitude-residing, endurance-trained runners during treadmill exercise. 24 elite endurance-trained men and women runners (age=21.5±3.3 yr, ht=174.8±9.3 cm, body mass=60.5±6.7 kg, PR 800 m 127.5±13.1 s) completed a graded exercise test (GXT) trial (VO2max=60.0±5.8 mL·kg(-1)·min(-1)), and returned 20 min after incremental exercise to complete a verification trial (VO2max=59.6±5.7 mL·kg(-1)·min(-1)) of constant load, supramaximal exercise. The incidence of 'true' VO2max confirmation using the verification trial was 24/24 (100%) with all participants revealing differences in VO2max≤3% (the technical error of our equipment) between the GXT and verification trials. These findings support use of the verification trial to confirm VO2max attainment in altitude-residing, endurance-trained runners. © Georg Thieme Verlag KG Stuttgart · New York.

  4. Non-exercise estimation of VO2max using the International Physical Activity Questionnaire

    Science.gov (United States)

    Schembre, Susan M.; Riebe, Deborah A.

    2011-01-01

    Non-exercise equations developed from self-reported physical activity can estimate maximal oxygen uptake (VO2max) as well as submaximal exercise testing. The International Physical Activity Questionnaire (IPAQ) is the most widely used and validated self-report measure of physical activity. This study aimed to develop and test a VO2max estimation equation derived from the IPAQ-Short Form (IPAQ-S). College-aged males and females (n = 80) completed the IPAQ-S and performed a maximal exercise test. The estimation equation was created with multivariate regression in a gender-balanced subsample of participants, equally representing five levels of fitness (n = 50) and validated in the remaining participants (n = 30). The resulting equation explained 43% of the variance in measured VO2max (SEE = 5.45 ml·kg-1·min-1). Estimated VO2max for 87% of individuals fell within acceptable limits of error observed with submaximal exercise testing (20% error). The IPAQ-S can be used to successfully estimate VO2max as well as submaximal exercise tests. Development of other population-specific estimation equations is warranted. PMID:21927551

  5. Steady exercise removes VO(2max) difference between mitochondrial genomic variants.

    Science.gov (United States)

    Marcuello, Ana; Martínez-Redondo, Diana; Dahmani, Yahya; Terreros, José L; Aragonés, Teresa; Casajús, José A; Echavarri, José M; Quílez, Julia; Montoya, Julio; López-Pérez, Manuel J; Díez-Sánchez, Carmen

    2009-09-01

    It has been clearly established that mitochondrial variants, among other potential factors, influence on VO(2max). With this study we sought to determine whether this genetic predisposition could be modified by steady exercise. Mitochondrial genetic variants were determined in 70 healthy controls (CON) and in 77 athletes who trained regularly (50 cyclists, aerobic training (AER), and 27 runners of 400m, anaerobic training (NoAER)). All of them were male Spanish Caucasian individuals. A maximum graded exercise test (GXT) in cycle-ergometer was performed to determine VO(2max) (mL kg(-1)min(-1)). Our results confirmed that, in CON, VO(2max) (P=0.007) was higher in Non-J than J individuals. Furthermore, we found that AER and NoAER showed, as it could be expected, higher VO(2max) than CON, but not differences between mitochondrial variants have been found. According with these findings, the influence of mitochondrial DNA (mtDNA) variants on VO(2max) has been confirmed, and a new conclusion has arisen: the steady exercise is able to remove this influence. The interest of these promising findings in muscular performance should be further explored, in particular, the understanding of potential applications in sport training and in muscle pathological syndromes.

  6. VO2 Max and Back and Leg Muscle Strength Profile of Universitas Padjadjaran Swimming Team

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    Pitriyani Nurul Pajar

    2016-12-01

    Full Text Available Background: Cardiorespiratory endurance (VO2 max and back and leg muscle strength are a few components required to support the performance of swimming athlete during competition. The objective of this study was to determine the VO2 max and back and leg muscle strength in high category level of Universitas Padjadjaran swimming team period 2014. Methods: A descriptive study was conducted to 19 swimmers of Universitas Padjadjaran in September 2014. The variables of this study were VO2 max and back and leg muscle strength. Then, the data were categorized based on the standard of The National Sports Committee of Indonesia. Results: The data obtained showed that the VO2 max of the majority of subjects was in the very good category (6/19 subjects and the back muscle strength of the majority of subjects was in the very good category (10/19 subjects. In contrast, the leg muscle strength of majority of subjects was in the low category (11/19 subjects. Conclusions: The VO2 max and back muscle strength in high category level of the swimming team fulfilled the standard of The National Sports Committee of Indonesia.

  7. Development of a branching submaximal treadmill test for predicting VO2max.

    Science.gov (United States)

    Swank, A M; Serapiglia, L; Funk, D; Adams, K J; Durham, M; Berning, J M

    2001-08-01

    This study determined the reliability and validity of a branching treadmill protocol in predicting VO2max. Thirty-seven, apparently healthy individuals (19 women and 18 men); volunteered to participate. On 2 separate testing days, each subject underwent maximal exercise testing using the protocol developed. Stepwise regression analysis indicated that the percentage of age-predicted maximum heart rate (APMHR) achieved at stage 3, speed and grade at stage 3, and APMHR accounted for 89% of the variance in VO2max. The 4 predictor variables were statistically significant (p VO2max for their clients outside the laboratory environment. Furthermore, our results indicate that using the proposed regression model is reliable and has received preliminary construct validity support.

  8. Effect of high-intensity interval training on cardiovascular function, VO2max, and muscular force.

    Science.gov (United States)

    Astorino, Todd A; Allen, Ryan P; Roberson, Daniel W; Jurancich, Matt

    2012-01-01

    The purpose of this study was to examine the effects of short-term high-intensity interval training (HIIT) on cardiovascular function, cardiorespiratory fitness, and muscular force. Active, young (age and body fat = 25.3 ± 4.5 years and 14.3 ± 6.4%) men and women (N = 20) of a similar age, physical activity, and maximal oxygen uptake (VO2max) completed 6 sessions of HIIT consisting of repeated Wingate tests over a 2- to 3-week period. Subjects completed 4 Wingate tests on days 1 and 2, 5 on days 3 and 4, and 6 on days 5 and 6. A control group of 9 men and women (age and body fat = 22.8 ± 2.8 years and 15.2 ± 6.9%) completed all testing but did not perform HIIT. Changes in resting blood pressure (BP) and heart rate (HR), VO2max, body composition, oxygen (O2) pulse, peak, mean, and minimum power output, fatigue index, and voluntary force production of the knee flexors and extensors were examined pretraining and posttraining. Results showed significant (p VO2max, O2 pulse, and Wingate-derived power output with HIIT. The magnitude of improvement in VO2max was related to baseline VO2max (r = -0.44, p = 0.05) and fatigue index (r = 0.50, p 0.05) in resting BP, HR, or force production was revealed. Data show that HIIT significantly enhanced VO2max and O2 pulse and power output in active men and women.

  9. Development of a rowing-specific VO2max field test.

    Science.gov (United States)

    Huntsman, Heather D; DiPietro, Loretta; Drury, Daniel G; Miller, Todd A

    2011-06-01

    The purpose of this study was to develop an aerobic capacity test for rowers using minimal equipment that could be used in the field. Thirty rowers (15 men and 15 women) between the ages of 18 and 26 years were recruited on a volunteer basis from the District of Columbia metro area. The testing protocol consisted of a maximum of 7 2-minute stages on a rowing ergometer, separated by 30-second breaks where lactic acid concentrations were analyzed. Starting intensity for men was 200 W, although women started at 150 W, and each stage increased by 50 W. Expired gasses were collected during the test, and athletes were asked to row until maximal volition so that the directly measured VO2max could be compared to predicted values. Peak heart rates from each completed stage were plotted, and regression equations were calculated to predict VO2max. Separate regression equations were calculated for men and women. The predicted VO2max values were approximately 23 and 25% lower than what was actually achieved for men and women, respectively. Heart rate was a stronger correlate of VO2max in men compared with in women. Among men, we observed a moderate and statistically significant correlation (r = 0.55; p = 0.05), whereas among women, no such agreement was observed (r = -0.05; p > 0.85). The principle finding of this study was that the test was adequate in predicting VO2max in men but was inadequate in its prediction in women. With slight modifications to the testing protocol, stronger correlations and a more accurate prediction of VO2max is expected in men.

  10. Markers of inflammation are inversely associated with VO2 max in asymptomatic men.

    Science.gov (United States)

    Kullo, Iftikhar J; Khaleghi, Mahyar; Hensrud, Donald D

    2007-04-01

    We investigated whether markers of inflammation, including a cytokine (IL-6), acute-phase reactants [C-reactive protein (CRP) and fibrinogen], and white blood cell (WBC) count are associated with maximal O(2) consumption (Vo(2 max)) in men without coronary heart disease (CHD). In asymptomatic men (n = 172, 51 +/- 9.3 yr old), Vo(2 max) was measured during a symptom-limited graded treadmill exercise test. Physical activity level was assessed by a standardized questionnaire. IL-6 and CRP were measured by immunoassays, fibrinogen by the Clauss method, and WBC count with a Coulter counter. IL-6 and CRP were logarithmically transformed to reduce skewness. Multivariable regression was used to assess whether markers of inflammation were associated with Vo(2 max) after adjustment for age, body mass index, CHD risk factors, and lifestyle variables (physical activity level, percent body fat, and alcohol intake). Vo(2 max) was 34.5 ml.kg(-1).min(-1) (SD 6.1). Log IL-6 (r = -0.38, P max). In separate multivariable linear regression models that adjusted for age, body mass index, CHD risk factors, and lifestyle variables, log IL-6 [beta-coeff = -1.66 +/- 0.63 (SE), P = 0.010], log CRP [beta-coeff = -0.99 +/- 0.33 (SE), P = 0.003], fibrinogen [beta-coeff = -1.51 +/- 0.44 (SE), P = 0.001], and WBC count [beta-coeff = -0.52 +/- 0.30 (SE), P = 0.088] were each inversely associated with Vo(2 max). In conclusion, higher circulating levels of IL-6, CRP, and fibrinogen are independently associated with lower Vo(2 max) in asymptomatic men.

  11. An alternative approach to the Army Physical Fitness Test two-mile run using critical velocity and isoperformance curves.

    Science.gov (United States)

    Fukuda, David H; Smith, Abbie E; Kendall, Kristina L; Cramer, Joel T; Stout, Jeffrey R

    2012-02-01

    The purpose of this study was to evaluate the use of critical velocity (CV) and isoperformance curves as an alternative to the Army Physical Fitness Test (APFT) two-mile running test. Seventy-eight men and women (mean +/- SE; age: 22.1 +/- 0.34 years; VO2(MAX): 46.1 +/- 0.82 mL/kg/min) volunteered to participate in this study. A VO2(MAX) test and four treadmill running bouts to exhaustion at varying intensities were completed. The relationship between total distance and time-to-exhaustion was tracked for each exhaustive run to determine CV and anaerobic running capacity. A VO2(MAX) prediction equation (Coefficient of determination: 0.805; Standard error of the estimate: 3.2377 mL/kg/min) was developed using these variables. Isoperformance curves were constructed for men and women to correspond with two-mile run times from APFT standards. Individual CV and anaerobic running capacity values were plotted and compared to isoperformance curves for APFT 2-mile run scores. Fifty-four individuals were determined to receive passing scores from this assessment. Physiological profiles identified from this procedure can be used to assess specific aerobic or anaerobic training needs. With the use of time-to-exhaustion as opposed to a time-trial format used in the two-mile run test, pacing strategies may be limited. The combination of variables from the CV test and isoperformance curves provides an alternative to standardized time-trial testing.

  12. Prior Knowledge of Trial Number Influences the Incidence of Plateau at VO2max.

    Science.gov (United States)

    Gordon, Dan; Caddy, Oliver; Merzbach, Viviane; Gernigon, Marie; Baker, James; Scruton, Adrian; Keiller, Don; Barnes, Richard

    2015-03-01

    The purpose of this study was to assess the VO2max plateau response at VO2max during a series of pre-determined trials. Ten male well-trained athletes (age, 23.0 ± 3.2; height, 183.3 ± 5.5 cm; mass 77.5 ± 11.1 Kg; VO2max 66.5 ± 5.0 ml(.)kg(-1,)min(-1)), but who were VO2max testing naïve and with prior-knowledge of trial number completed four incremental tests to volitional exhaustion, separated by ~72-h for the determination of VO2max and gas exchange threshold. Throughout all trials VO2max was recorded on a breath-by-breath basis using a pre-calibrated metabolic cart, using a plateau criterion of Δ VO2 ≤1.5 ml(.)kg(-1.)min(-1) over the final 2 consecutive 30 s sampling periods. A significant difference was observed between trial-1 and trial-4 for plateau incidence (p = 0.0285) rising from 20% in trial-1 to a 70% response rate in trial-4. Furthermore a significant difference was observed for VO2dif (difference between criterion value and Δ VO2) in trial-1, 1.02 ± 1.69 ml(.)kg(-1.)min(-1) (p = 0.038), with non-significant differences observed for all other trials, despite a non-significant difference for VO2max across all trials (p > 0.05). Finally, a significant difference was observed for effort perception (RPE) at volitional exhaustion between trial-1 (17.7 ± 1.3) and trial-4 (19.0 ± 1.4) (p = 0.0052). These data indicate that prior-knowledge of trial number can influence the manifestation of the VO2 plateau in a group of well-trained male athletes, thereby suggesting that a form of effort control is established in order to preserve the finite anaerobic capacity. Key pointsIn well-trained athletes the incidence of plateau at VO2max increases in conjunction with an increase in trial number and the associated sensations of pain and fatigue.By informing the participant of the number of trials to be completed a closed-loop condition is developed whereby effort in all trials is compared to a perceptually developed template.Closed-loop condition leads to a

  13. The reliability of aerobic capacity (VO2max) testing in adolescent girls.

    Science.gov (United States)

    Pivarnik, J M; Dwyer, M C; Lauderdale, M A

    1996-09-01

    Despite the fact that our subjects were naive regarding the test procedures, it appears that aerobic fitness testing using an incremental treadmill protocol is extremely reliable in adolescent girls. In addition, day-to-day variability of VO2max in our subjects averaged less than 5%, which is similar to results obtained with adults (Katch, Sady, & Freedson, 1982). Finally, it was most encouraging to find that a single VO2max test trial resulted in high reliability coefficients. This finding should provide a great deal of confidence to investigators who are performing aerobic fitness tests on large numbers of subjects where multiple testing is neither practical nor cost-effective.

  14. Supramaximal testing to confirm attainment of VO2max in sedentary men and women.

    Science.gov (United States)

    Astorino, T A; White, A C; Dalleck, L C

    2009-04-01

    Supramaximal testing is widely used to verify VO2max attainment, yet its efficacy in sedentary subjects is unknown. The aim of the study was to test this hypothesis in men and women completing maximal cycle ergometry. Fifteen sedentary subjects (age=22.4+/-3.9 year) completed incremental exercise, and returned at least 24 h later to complete constant load exercise at 105% peak work rate (Wmax). Another group of nine sedentary men and women (age=21.8+/-5 year) completed supramaximal exercise at 115% Wmax 1-1.5 h after incremental exercise. During exercise, gas exchange data and heart rate (HR) were continuously obtained. VO2max was similar (p>0.05) between incremental and supramaximal exercise in subjects in the first (32.32+/-4.81 mL/kg/min vs. 31.80+/-5.35 mL/kg/min) and second subset (40.63+/-3.61 mL/kg/min vs. 41.66+/-5.55 mL/kg/min). Maximal HR was lower (pTest-retest reliability (r=0.81-0.89, pVO2max was high during repeated bouts of supramaximal testing. Findings support use of this protocol to confirm VO2max attainment in healthy, sedentary men and women completing incremental cycle ergometry.

  15. Prediction VO2max during cycle ergometry based on submaximal ventilatory indicators.

    Science.gov (United States)

    Nunes, Rodolfo Alkmim Moreira; Vale, Rodrigo Gomes de Souza; Simão, Roberto; de Salles, Belmiro Freitas; Reis, Victor Machado; Novaes, Jefferson da Silva; Miranda, Humberto; Rhea, Matthew R; Medeiros, Aldo da Cunha

    2009-09-01

    There are several equations to predict maximum oxygen consumption (VO2max) from ergometric test variables on different ergometers. However, a similar equation using ventilatory thresholds of ergospirometry in a submaximal test on a cycle ergometer is unavailable. The aim of the present study was to assess the accuracy of VO2max prediction models based on indicators of submaximal effort. Accordingly, 4,640 healthy, nonathlete women ages 20 years and older volunteered to be tested on a cycle ergometer using a maximum incremental protocol. The subjects were randomly assigned to 2 groups: group A (estimation) and group B (validation). From the independent variables of weight in kilograms, the second workload threshold (WT2), and heart rate of the second threshold (HRT2), it was possible to build a multiple linear regression model to predict maximal oxygen consumption (VO2max = 40.302 - 0.497 [Weight] - 0.001 [HRT2] + 0.239 [WT2] in mL O2/kg/min(-1); r = 0.995 and standard error of the estimate [SEE] = 0.68 mL O2/kg/min(-1)). The cross-validation method was used in group B with group A serving as the basis for building the model and the validation dataset. The results showed that, in healthy nonathlete women, it is possible to predict VO2max with a minimum of error (SEE = 1.00%) from submaximal indicators obtained in an incremental test.

  16. Prior Knowledge of Trial Number Influences the Incidence of Plateau at VO2max

    Directory of Open Access Journals (Sweden)

    Dan Gordon

    2015-01-01

    Full Text Available The purpose of this study was to assess the VO2max plateau response at VO2max during a series of pre-determined trials. METHODS: Ten male well-trained athletes (age, 23.0 ± 3.2; height, 183.3 ± 5.5 cm; mass 77.5 ± 11.1 Kg; VO2max 66.5 ± 5.0 ml.kg-1,min-1, but who were VO2max testing naïve and with prior-knowledge of trial number completed four incremental tests to volitional exhaustion, separated by ~72-h for the determination of VO2max and gas exchange threshold. Throughout all trials VO2max was recorded on a breath-by-breath basis using a pre-calibrated metabolic cart, using a plateau criterion of Δ VO2 ≤1.5 ml.kg-1.min-1 over the final 2 consecutive 30 s sampling periods. A significant difference was observed between trial-1 and trial-4 for plateau incidence (p = 0.0285 rising from 20% in trial-1 to a 70% response rate in trial-4. Furthermore a significant difference was observed for VO2dif (difference between criterion value and Δ VO2 in trial-1, 1.02 ± 1.69 ml.kg-1.min-1 (p = 0.038, with non-significant differences observed for all other trials, despite a non-significant difference for VO2max across all trials (p > 0.05. Finally, a significant difference was observed for effort perception (RPE at volitional exhaustion between trial-1 (17.7 ± 1.3 and trial-4 (19.0 ± 1.4 (p = 0.0052. These data indicate that prior-knowledge of trial number can influence the manifestation of the VO2 plateau in a group of well-trained male athletes, thereby suggesting that a form of effort control is established in order to preserve the finite anaerobic capacity.

  17. Frequency of the VO2max plateau phenomenon in world-class cyclists.

    Science.gov (United States)

    Lucía, A; Rabadán, M; Hoyos, J; Hernández-Capilla, M; Pérez, M; San Juan, A F; Earnest, C P; Chicharro, J L

    2006-12-01

    We aimed to determine the frequency of the VO2max plateau phenomenon in top-level male professional road cyclists (n = 38; VO2max [mean +/- SD]: 73.5 +/- 5.5 ml.kg(-1).min(-1)) and in healthy, sedentary male controls (n = 37; VO2max: 42.7 +/- 5.6 ml.kg(-1).min(-1)). All subjects performed a continuous incremental cycle-ergometer test of 1-min workloads until exhaustion. Power output was increased from a starting value of 25 W (cyclists) or 20 W (controls) at the rate of 25 W.min(-1) (cyclists) or 20 W.min(-1) (controls) until volitional exhaustion. We measured gas-exchange and heart rate (HR) throughout the test. Blood concentrations of lactate (BLa) were measured at end-exercise in both groups. We defined maximal exercise exertion as the attainment of a respiratory exchange rate (RER) >or= 1.1; HR > 95 % age-predicted maximum; and BLa > 8 mmo.l(-1). The VO2max plateau phenomenon was defined as an increase in two or more consecutive 1-min mean VO2 values of less than 1.5 ml.kg(-1).min(-1). Most cyclists met our criteria for maximal exercise effort (RER > 1.1, 100 %; 95 % predicted maximal HR [HRmax], 82 %; BLa > 8 mmol.l(-1), 84 %). However, the proportion of cyclists attaining a V.O (2max) plateau was considerably lower, i.e., 47 %. The majority of controls met the criteria for maximal exercise effort (RER > 1.1, 100 %; predicted HRmax, 68 %; BLa > 8 mmol. l(-1), 73 %), but the proportion of these subjects with a VO2max plateau was only 24 % (significantly lower proportion than in cyclists [p < 0.05]). Scientists should consider 1) if typical criteria of attainment of maximal effort are sufficiently stringent, especially in elite endurance athletes; and 2) whether those humans exhibiting the VO2max plateau phenomenon are those who perform an absolute maximum effort or there are additional distinctive features associated with this phenomenon.

  18. STUDY OF VO 2 MAX DURING PHASES OF MENSTRUATION IN YOUNG FEMALE ATHLETES

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    Sunitha

    2013-06-01

    Full Text Available ABSTRACT: Context: The menstrual cycle is a natural monthly event in y oung women, coordinated by the hypothalamic-pituitary ovarian axis and may influence physiological and pathological changes that occur throughout the life time of the woman. There is a cyclical change in sex hormones during the course of menstrual cycle that have the potential effects on exercise capacity and performance through numerous mechanisms, such a s substrate metabolism, cardiorespiratory function, thermoregulation, psychological factors a nd injuries. Consequently hormone level changes may theoretically lead to either improved or decrea sed performance at various times throughout the menstrual cycle. Physiological indices such as heart rate, tension, VO 2 max and aerobic power are of the main indicators of exercise performance, a potential change in these indices over the menstrual cycle will have large practical implicati ons for female athletes. VO 2 max is highly predictive of endurance performance, hence the pres ent study was done to evaluate whether there is any changes in the VO 2 max during phases of menstruation in young female athletes. Aim: The present study was done to evaluate the VO 2 max during phases of menstruation in young female athletes. Settings and Design: The present study was a cross sectional study consi sting of 30 healthy female athletes of 17-20 years of age. Materials and Methods: This study was conducted in the Department of Physiology, Adichunchanagiri inst itute of medical sciences after the institutional ethical clearance and written consent from each par ticipant. VO 2 max (maximum oxygen uptake was indirectly assessed by the Astrand nomogram met hod from submaximal exercise data obtained using Harvard step test during all the three phases of menstrual cycle. Results: The parameters were analyzed for statistical significance using St udents‘t’ test and p<0.05 was considered the level of significance. There were no significant

  19. Earbud-Based Sensor for the Assessment of Energy Expenditure, Heart Rate, and VO2max

    Science.gov (United States)

    LeBoeuf, Steven F.; Aumer, Michael E.; Kraus, William E.; Johnson, Johanna L.; Duscha, Brian

    2014-01-01

    Introduction/Purpose The goal of this program was to determine the feasibility of a novel noninvasive, highly miniaturized optomechanical earbud sensor for accurately estimating total energy expenditure (TEE) and maximum oxygen consumption (VO2max). The optomechanical sensor module, small enough to fit inside commercial audio earbuds, was previously developed to provide a seamless way to measure blood flow information during daily life activities. The sensor module was configured to continuously measure physiological information via photoplethysmography (PPG) and physical activity information via accelerometry. This information was digitized and sent to a microprocessor where digital signal processing (DSP) algorithms extract physiological metrics in real-time. These metrics were streamed wirelessly from the earbud to a computer. Methods In this study, 23 subjects of multiple physical habitus were divided into a training group of 14 subjects and a validation group of 9 subjects. Each subject underwent the same exercise measurement protocol consisting of treadmill-based cardiopulmonary exercise (CPX) testing to reach VO2max. Benchmark sensors included a 12-lead electrocardiography (ECG) sensor for measuring heart rate, a calibrated treadmill for measuring distance and speed, and a gas-exchange analysis instrument for measuring TEE and VO2max. The earbud sensor was the device under test (DUT). Benchmark and DUT data collected from the 14-person training dataset study were integrated into a preconceived statistical model for correlating benchmark data with earbud sensor data. Coefficients were optimized, and the optimized model was validated in the 9-person validation dataset. Results It was observed that the earbud sensor estimated TEE and VO2max with mean ± SD percent estimation errors of −0.7 ± 7.4% and −3.2 ± 7.3% respectively. Conclusion The earbud sensor can accurately estimate TEE and VO2max during CPX testing. PMID:24743110

  20. Earbud-based sensor for the assessment of energy expenditure, HR, and VO2max.

    Science.gov (United States)

    Leboeuf, Steven Francis; Aumer, Michael E; Kraus, William E; Johnson, Johanna L; Duscha, Brian

    2014-01-01

    The goal of this program was to determine the feasibility of a novel noninvasive, highly miniaturized optomechanical earbud sensor for accurately estimating total energy expenditure (TEE) and maximum oxygen consumption (VO2max). The optomechanical sensor module, small enough to fit inside commercial audio earbuds, was previously developed to provide a seamless way to measure blood flow information during daily life activities. The sensor module was configured to continuously measure physiological information via photoplethysmography and physical activity information via accelerometry. This information was digitized and sent to a microprocessor where digital signal-processing algorithms extract physiological metrics in real time. These metrics were streamed wirelessly from the earbud to a computer. In this study, 23 subjects of multiple physical habitus were divided into a training group of 14 subjects and a validation group of 9 subjects. Each subject underwent the same exercise measurement protocol consisting of treadmill-based cardiopulmonary exercise testing to reach VO2max. Benchmark sensors included a 12-lead ECG sensor for measuring HR, a calibrated treadmill for measuring distance and speed, and a gas-exchange analysis instrument for measuring TEE and VO2max. The earbud sensor was the device under test. Benchmark and device under test data collected from the 14-person training data set study were integrated into a preconceived statistical model for correlating benchmark data with earbud sensor data. Coefficients were optimized, and the optimized model was validated in the 9-person validation data set. It was observed that the earbud sensor estimated TEE and VO2max with mean ± SD percent estimation errors of -0.7 ± 7.4% and -3.2 ± 7.3%, respectively. The earbud sensor can accurately estimate TEE and VO2max during cardiopulmonary exercise testing.

  1. Bone mass in girls according to their BMI, VO2 max, hours and years of practice.

    Science.gov (United States)

    Ubago-Guisado, Esther; Martinez-Rodriguez, Alejandro; Gallardo, Leonor; Sánchez-Sánchez, Javier

    2016-11-01

    The accumulation of bone mass during puberty is related with bone health in adulthood. This accumulation is influenced by diverse factors such as body mass index (BMI), maximal oxygen uptake (VO2 max), hours of training and years of sport practice. For this reason, the objective of this study is to analyse the influence of these variables on bone mass in young female athletes. The sample is formed of 120 healthy girls with ages between 9 and 13 (11.32 ± 1.6 years old), divided into two groups depending on their BMI, VO2 max, hours of training and years of sport practice. The participants completed a series of tests to evaluate level of sexual development, body composition (fat mass, lean mass and bone mass) and physical condition. The results show higher values of total lean mass, total fat mass and percentage of body fat in the groups with higher BMI in prepubertal girls and pubertal girls (p VO2 max, in the prepubertal group, girls with lower VO2 max had higher values of total fat mass (p VO2 max also showed a higher total fat mass (p < .05). The studied variables account for a 85% and 75.4% of the variance of total bone mineral content and bone mineral density (BMD), respectively. In conclusion, the content and BMD are closely related with muscle mass and sports practice in young females. The amount of fat mass showed no association with bone mass and physical condition has an indirect relationship with bone development.

  2. A new submaximal cycle ergometer test for prediction of VO2max.

    Science.gov (United States)

    Ekblom-Bak, E; Björkman, F; Hellenius, M-L; Ekblom, B

    2014-04-01

    Maximal oxygen uptake (VO2max) is an important, independent predictor of cardiovascular health and mortality. Despite this, it is rarely measured in clinical practice. The aim of this study was to create and evaluate a submaximal cycle ergometry test based on change in heart rate (HR) between a lower standard work rate and an individually chosen higher work rate. In a mixed population (n = 143) with regard to sex (55% women), age (21-65 years), and activity status (inactive to highly active), a model included change in HR per unit change in power, sex, and age for the best estimate of VO2max. The association between estimated and observed VO2max for the mixed sample was r = 0.91, standard error of estimate = 0.302 L/min, and mean measured VO2max = 3.23 L/min. The corresponding coefficient of variation was 9.3%, a significantly improved precision compared with one of the most commonly used submaximal exercise tests, the Åstrand test, which in the present study was estimated to be 18.1%. Test-retest reliability analysis over 1 week revealed no mean difference in the estimated VO2max (-0.02 L/min, 95% confidence interval: -0.07-0.03). The new test is low-risk, easily administered, and valid for a wide capacity range, and is therefore suitable in situations as health evaluations in the general population. © 2012 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. Why is VO2 max after altitude acclimatization still reduced despite normalization of arterial O2 content?

    DEFF Research Database (Denmark)

    Calbet, J A L; Boushel, Robert Christopher; Radegran, G

    2003-01-01

    Acute hypoxia (AH) reduces maximal O2 consumption (VO2 max), but after acclimatization, and despite increases in both hemoglobin concentration and arterial O2 saturation that can normalize arterial O2 concentration ([O2]), VO2 max remains low. To determine why, seven lowlanders were studied at VO2...

  4. Crossvalidation of two heart rate-based equations for predicting VO2max in white and black men.

    Science.gov (United States)

    Esco, Michael R; Olson, Michele S; Williford, Henry N; Mugu, Emmanuel M; Bloomquist, Barbara E; McHugh, Aindrea N

    2012-07-01

    The purpose of this investigation was to crossvalidate 2 equations that use the ratio of maximal heart rate (HRmax) to resting HR (HRrest) for predicting maximal oxygen consumption (VO2max) in white and black men. One hundred and nine white (n = 51) and black (n = 58) men completed a maximal exercise test on a treadmill to determine VO2max. The HRrest and HRmax were used to predict VO2max via the HRindex and HRratio equations. Validity statistics were done to compare the criterion versus predicted VO2max values across the entire cohort and within each race separately. For the entire group, VO2max was significantly overestimated with the HRindex equation, but the HRratio equation yielded no significant difference compared with the criterion. In addition, there were no significant differences shown between VO2max and either HR-based prediction equation for the white subgroup. However, both equations significantly overestimated VO2max in the black group. Furthermore, large standard error of estimates (ranging from 6.92 to 7.90 ml·kg(-1)·min(-1)), total errors (ranging from 8.30 to 8.62 ml·kg(-1)·min(-1)), and limits of agreement (ranging from upper limits of 16.65 to lower limits of -18.25 ml·kg(-1)·min(-1)) were revealed when comparing the predicted to criterion VO2max for both the groups. Considering the results of this investigation, the HRratio and HRindex methods appear to crossvalidate and prove useful for estimating the mean VO2max in white men as a group but not for an age-matched group of black men. However, because of inflated values for error, caution should be exercised when using these methods to predict individual VO2max.

  5. Predição da potência aeróbia (VO2máx de crianças e adolescentes em teste incremental na esteira rolante Prediction of aerobic power (VO2max of children and adolescents during an incremental treadmill test

    Directory of Open Access Journals (Sweden)

    Fabiana Andrade Machado

    2013-03-01

    Full Text Available O consumo máximo de oxigênio (VO2máx é a quantidade máxima de energia que pode ser produzida pelo metabolismo aeróbio em determinada unidade de tempo, podendo ser determinado direta ou indiretamente através de equações preditivas. O objetivo deste trabalho foi elaborar uma equação preditiva específica para determinar o VO2máx de meninos de 10 a 16 anos. Quarenta e dois meninos realizaram teste ergoespirométrico de corrida em esteira rolante com velocidade inicial de 9 km/h até exaustão voluntária. Através da regressão linear múltipla foi possível desenvolver a seguinte equação para a determinação indireta do VO2máx: VO2máx (ml/min = -1574,06 + (141,38 x Vpico + (48,34 * Massa corporal, com erro padrão de estimativa = 191,5 ml/min (4,10 ml/kg/min e o coeficiente de determinação = 0,934. Sugerimos que esta é uma fórmula adequada para predizer o VO2máx para esta população.The maximal oxygen uptake (VO2max is the maximal quantity of energy that can be produced by the aerobic metabolism in certain time unity. It can be determined direct or indirectly by predictive equations. The objective of this study was to make a specific predictive equation to determine the VO2max from boys aged 10-16 years-old. Forty-two boys underwent a treadmill running ergospirometric test, with the initial velocity set at 9 km/h, until voluntary exhaustion. By the multiple linear regression was possible to develop the following equation for the indirect determination of the VO2max: VO2max (ml/min = -1574.06 + (141.38 x Vpeak + (48.34 * Body mass, with standard error of estimate = 191.5 ml/min (4.10 ml/kg/min and coefficient of determination = 0.934. We suggest that this formula is appropriate to predict VO2max for this population.

  6. Monitoring VO2max during fourteen weeks of endurance training using the CardioCoach.

    Science.gov (United States)

    Vehrs, Pat R; Keller, David M; George, James D; Hager, Ronald L; Fellingham, Gilbert W

    2007-02-01

    This study evaluated the validity of the desktop CardioCoach metabolic system to measure VO2max and VEmax. Sixteen subjects (mean age = 19.5 +/- 3.2 years) completed 2 maximal graded exercise tests following the same protocol before and after 7 and 14 weeks of endurance training. Subjects' VO2max and VEmax were measured by either the CardioCoach or the ParvoMedics TrueOne 2400 metabolic measurement system (TrueOne). An alpha level of significance of p test completion and the final treadmill grade of the exercise tests performed by both the CardioCoach and the TrueOne increased over the 3 testing periods, confirming an improvement in cardiorespiratory fitness resulting from the 14 weeks of training. A linear growth curve analysis indicated that there were statistically significant differences between VO2max (ml x kg(-1) x min(-1)) as measured by the TrueOne and the CardioCoach before (44.4 +/- 5.0 and 49.3 +/- 5.4) and after 7 weeks (46.0 +/- 5.2 and 48.2 +/- 5.4) of training but not after 14 weeks of training (47.8 +/- 5.6 and 48.4 +/- 5.2). Significant differences also existed in VEmax (L x min(-1)) as measured by the TrueOne and the CardioCoach before (76.8 +/- 17.7 and 71.9 +/- 13.7), after 7 weeks (81.4 +/- 16.2 and 72.8 +/- 14.1), and after 14 weeks (86.8 +/- 19.4 and 74.2 +/- 13.1) of training. Although significant growth of VO2max (0.24 ml x kg(-1) x min(-1) x wk(-1)) and VEmax (0.71 L x min(-1) x wk(-1)) was measured by the TrueOne over 14 weeks of training, the CardioCoach was unable to detect growth in VO2max (-0.02 ml x kg(-1) x min(-1) x wk(-1)) or VEmax (0.17 L x min(-1) x wk(-1)). This study indicates that the CardioCoach did not accurately measure or monitor changes in VO2max or VEmax resulting from training.

  7. Effects of concurrent training on explosive strength and VO(2max) in prepubescent children.

    Science.gov (United States)

    Marta, C; Marinho, D A; Barbosa, T M; Izquierdo, M; Marques, M C

    2013-10-01

    The purpose of this study was to compare the effects of an 8-weeks training period of resistance training alone (GR), combined resistance and endurance training (GCON) and a control group (GC) on explosive strength and V(O2max) in a large sample of prepubescent boys and girls. 125 healthy children (58 boys, 67 girls), aged 10-11 years old (10.8±0.4 years) were assigned into 2 training groups to train twice a week for 8 weeks: GR (19 boys, 22 girls), GCON (21 boys, 24 girls) and a control group (GC: 18 boys, 21 girls; no training program). A significant but medium-sized increase from pre- to the post-training in the vertical jump (Effect size=0.22, F=34.44, ptraining group (GR and GCON) and sex factors did not significantly influence the evolution of strength variables from pre- to the post-training. The V(O2max) increased significantly only in GCON. Concurrent training is equally effective on training-induced explosive strength, and more efficient than resistance training only for V(O2max), in prepubescent boys and girls. This should be taken into consideration in order to optimize strength training school-based programs. © Georg Thieme Verlag KG Stuttgart · New York.

  8. EVALUATION AND COMPARISON OF VO2MAX ASSESSMENT MODELS IN HIGH SCHOOL STUDENTS

    Directory of Open Access Journals (Sweden)

    Lotfali Bolboli

    2013-02-01

    Full Text Available The purpose of this study was to evaluation and comparison of VO2max assessment models in students. Thirty students from high schools of Ardabil city were selected randomly and served as subjects in this study (age: 15.73±0.69 year, height: 169.46±8.1 cm, weight: 61.70±9.32 kg. Subjects were divided into two groups. In one group Rockport test was used to estimate their VO2 max and in other group Balk test was used for the same purpose. Also, the VO2max of both groups were examined by a standard treadmill test and the results were compared with the results of field tests. The one way of ANOVA and Tukey's post-hoc tests were used for data analysis (p>0/05. The results showed that there were significant differences between the results of the field tests and standard treadmill test (Bruce: 40.93±5.83 vs. Rockport: 58.71±2.73 and Balke: 52.09± 6.18. As a result of these findings it was concluded that the regression equations used in this study used is not suitable for 15-17 (yr boys and does not estimate their aerobic power correctly.

  9. Determinants of VO2 max decline with aging: an integrated perspective.

    Science.gov (United States)

    Betik, Andrew C; Hepple, Russell T

    2008-02-01

    Aging is associated with a progressive decline in the capacity for physical activity. Central to this decline is a reduction in the maximal rate of oxygen utilization, or VO2 max. This critical perspective examines the roles played by the factors that determine the rate of muscle oxygen delivery versus those that determine the utilization of oxygen by muscle as a means of probing the reasons for VO2 max decline with aging. Reductions in muscle oxygen delivery, principally due to reduced cardiac output and perhaps also a maldistribution of cardiac output, appear to play the dominant role up until late middle age. On the other hand, there is a decline in skeletal muscle oxidative capacity with aging, due in part to mitochondrial dysfunction, which appears to play a particularly important role in extreme old age (senescence) where skeletal muscle VO2 max is observed to decline by approximately 50% even under conditions of similar oxygen delivery as young adult muscle. It is noteworthy that at least the structural aspects of the capillary bed do not appear to be reduced in a manner that would compromise the capacity for muscle oxygen diffusion even in senescence.

  10. Development of a hockey-specific, skate-treadmill VO2 max protocol.

    Science.gov (United States)

    Dreger, R W; Quinney, H A

    1999-12-01

    The purpose of this study was to investigate a protocol for the determination of VO2 max utilizing a motor-driven skate treadmill (ST). On separate days, 6 male hockey players completed a ST and a cycle ergometer (BK) VO2 max protocol. The results showed no significant difference between the ST and BK protocols for relative (60.4 +/- 5.09 vs. 59.0 +/- 8.31 ml.kg-1.min-1) and absolute VO2 max values (4.51 +/- 0.50 vs. 4.39 +/- 0.59 L.min-1), respectively. Significantly higher HR max was recorded during the ST protocol (202.3 +/- 4.27 vs. 200.7 +/- 4.55 b.min-1) (p < 0.05). Peak VE and VT were nonsignificant between the two conditions. However, peak f was higher for the ST protocol (63.0 +/- 7.56 vs. 60.2 +/- 7.76 breath.min-1) (p < 0.05). Although the physiological response to both protocols was similar, the ST protocol replicates a hockey stride, which may provide more applicable information for the development of training programs.

  11. The effects of uphill vs. level-grade high-intensity interval training on VO2max, Vmax, V(LT), and Tmax in well-trained distance runners.

    Science.gov (United States)

    Ferley, Derek D; Osborn, Roy W; Vukovich, Matthew D

    2013-06-01

    Uphill running represents a frequently used and often prescribed training tactic in the development of competitive distance runners but remains largely uninvestigated and unsubstantiated as a training modality. The purpose of this investigation included documenting the effects of uphill interval training compared with level-grade interval training on maximal oxygen consumption (VO2max), the running speed associated with VO2max (Vmax), the running speed associated with lactate threshold (V(LT)), and the duration for which Vmax can be sustained (Tmax) in well-trained distance runners. Thirty-two well-trained distance runners (age, 27.4 ± 3.8 years; body mass, 64.8 ± 8.9 kg; height, 173.6 ± 6.4 cm; and VO2max, 60.9 ± 8.5 ml·min(-1)·kg(-1)) received assignment to an uphill interval training group (G(Hill) = 12), level-grade interval training group (G(Flat) = 12), or control group (G(Con) = 8). G(Hill) and G(Flat) completed 12 interval and 12 continuous running sessions over 6 weeks, whereas G(Con) maintained their normal training routine. Pre- and posttest measures of VO2max, Vmax, V(LT), and Tmax were used to assess performance. A 3 × 2 repeated measures analysis of variance was performed for each dependent variable and revealed a significant difference in Tmax in both G(Hill) and G(Flat) (p interval training can induce significant improvements in a run-to-exhaustion test in well-trained runners at the speed associated with VO2max but that traditional level-grade training produces greater gains.

  12. Estimation of VO2max from the ratio between HRmax and HRrest--the Heart Rate Ratio Method.

    Science.gov (United States)

    Uth, Niels; Sørensen, Henrik; Overgaard, Kristian; Pedersen, Preben K

    2004-01-01

    The effects of training and/or ageing upon maximal oxygen uptake ( VO(2max)) and heart rate values at rest (HR(rest)) and maximal exercise (HR(max)), respectively, suggest a relationship between VO(2max) and the HR(max)-to-HR(rest) ratio which may be of use for indirect testing of VO(2max). Fick principle calculations supplemented by literature data on maximum-to-rest ratios for stroke volume and the arterio-venous O(2) difference suggest that the conversion factor between mass-specific VO(2max) (ml.min(-1).kg(-1)) and HR(max).HR(rest)(-1) is approximately 15. In the study we experimentally examined this relationship and evaluated its potential for prediction of VO(2max). VO(2max) was measured in 46 well-trained men (age 21-51 years) during a treadmill protocol. A subgroup ( n=10) demonstrated that the proportionality factor between HR(max).HR(rest)(-1) and mass-specific VO(2max) was 15.3 (0.7) ml.min(-1).kg(-1). Using this value, VO(2max) in the remaining 36 individuals could be estimated with an SEE of 0.21 l.min(-1) or 2.7 ml.min(-1).kg(-1) (approximately 4.5%). This compares favourably with other common indirect tests. When replacing measured HR(max) with an age-predicted one, SEE was 0.37 l.min(-1) and 4.7 ml.min(-1).kg(-1) (approximately 7.8%), which is still comparable with other indirect tests. We conclude that the HR(max)-to-HR(rest) ratio may provide a tool for estimation of VO(2max) in well-trained men. The applicability of the test principle in relation to other groups will have to await direct validation. VO(2max) can be estimated indirectly from the measured HR(max)-to-HR(rest) ratio with an accuracy that compares favourably with that of other common indirect tests. The results also suggest that the test may be of use for VO(2max) estimation based on resting measurements alone.

  13. Antepartum cardiorespiratory fitness (CRF) quantification by estimation of maximal oxygen consumption (Vo2 max) in pregnant South Indian women.

    Science.gov (United States)

    Chakaravertty, Biswajit; Parkavi, K; Coumary, Sendhil A; Felix, A J W

    2012-04-01

    The aim of the study was to calculate the maximal oxygen consumption (Vo2max) for pregnant women of varying trimesters and to quantify the cardiorespiratory fitness (CRF)with the objective of being able to determine the exercise dose for antenatal women which can be prescribed to achieve optimal exercise benefits during various trimesters. A study group comprising 64 pregnant women with uncomplicated singleton pregnancy and control group with 77 non-pregnant women were subjected to Cooper's 12 minutes walk test. From the distance covered in 12 minutes, Vo2max was calculated. The Vo2max values were statistically analysed between the non-pregnant and pregnant and also its variability among the trimesters. Percentile tables of Vo2max were drawn and multiple comparisons were applied. Results show that the Vo2max values among non-pregnant and first trimester ranges between 18 and 22 ml/kg/minute. Trimesters II and III had a range of Vo2max values between 16-20 and 14-18 ml/kg/minute respectively. The CRF of pregnant women significantly reduced to 6%, 9% and 18% in each trimester respectively when compared with the reference table framed out of non-pregnant Vo2max values. Among the study group the reduction in Vo2max values had no statistical significance between first 2 trimesters but trimester III significantly differs from other trimesters. The exercise prescription cannot be the same for pregnant and non-pregnant women. Even among the pregnant women, III trimester needs separate exercise prescription from the other two trimesters as CRF is markedly compromised towards term.

  14. Modality determines VO2max achieved in self-paced exercise tests: validation with the Bruce protocol.

    Science.gov (United States)

    Hanson, Nicholas J; Scheadler, Cory M; Lee, Taylor L; Neuenfeldt, Noah C; Michael, Timothy J; Miller, Michael G

    2016-07-01

    The Bruce protocol is traditionally used to assess maximal cardiorespiratory fitness (VO2max), but may have limitations, such as an unknown duration and large work rate increases. The use of self-paced VO2max tests (SPVs) may be beneficial if they are able to elicit similar maximal values in a set period of time. In addition, differences in modality between SPVs have not been explored. The purpose of this study was to compare SPVs, utilizing two different modes, with the Bruce (treadmill) protocol. Thirteen healthy, recreationally active individuals (eight men, five women) volunteered and participated in three different laboratory visits with each utilizing a different VO2max testing protocol. The first visit consisted of the Bruce protocol test, and the remaining visits entailed a maximal SPV on a treadmill (TM SPV) and a cycle ergometer (CE SPV). There were no differences in VO2max values between the TM SPV and the Bruce protocol tests (55.6 ± 4.9 vs. 56.2 ± 6.8, respectively; p = .510). As expected, the CE SPV (48.3 ± 7.6) was significantly lower than the other two tests (p VO2max as the Bruce protocol and did so with less incline and in less time suggesting that there are no changes in the limits of VO2max even when the test is self-paced and perceptually regulated.

  15. Initial Weekly HRV Response is Related to the Prospective Change in VO2max in Female Soccer Players.

    Science.gov (United States)

    Esco, M R; Flatt, A A; Nakamura, F Y

    2016-06-01

    The aim of this study was to determine whether the early response in weekly measures of HRV, when derived from a smartphone application, were related to the eventual change in VO2max following an off-season training program in female soccer athletes. 9 female collegiate soccer players participated in an 11-week off-season conditioning program. In the week immediately before and after the training program, each participant performed a test on a treadmill to determine maximal oxygen consumption (VO2max). Daily measures of the log-transformed root mean square of successive R-R intervals (lnRMSSD) were performed by the participants throughout week 1 and week 3 of the conditioning program. The mean and coefficient of variation (CV) lnRMSSD values of week 1 showed small (r=- 0.13, p=0.74) and moderate (r=0.57, p=0.11), respectively, non-significant correlations to the change in VO2max at the end of the conditioning program (∆VO2max). Significant and near-perfect correlation was found between the change in the weekly mean lnRMSSD values from weeks 1 and 3 (∆lnRMSSDM) and ∆VO2max (r=0.90, p=0.002). The current results have identified that the initial change in weekly mean lnRMSSD from weeks 1 to 3 of a conditioning protocol was strongly associated with the eventual adaptation of VO2max.

  16. Limitations to vasodilatory capacity and .VO2 max in trained human skeletal muscle.

    Science.gov (United States)

    Barden, Jeremy; Lawrenson, Lesley; Poole, Jennifer G; Kim, Jeannie; Wray, D Walter; Bailey, Damian M; Richardson, Russell S

    2007-05-01

    To further explore the limitations to maximal O(2) consumption (.VO(2 max)) in exercise-trained skeletal muscle, six cyclists performed graded knee-extensor exercise to maximum work rate (WR(max)) in hypoxia (12% O(2)), hyperoxia (100% O(2)), and hyperoxia + femoral arterial infusion of adenosine (ADO) at 80% WR(max). Arterial and venous blood sampling and thermodilution blood flow measurements allowed the determination of muscle O(2) delivery and O(2) consumption. At WR(max), O(2) delivery rose progressively from hypoxia (1.0 +/- 0.04 l/min) to hyperoxia (1.20 +/- 0.09 l/min) and hyperoxia + ADO (1.33 +/- 0.05 l/min). Leg .VO(2 max) varied with O(2) availability (0.81 +/- 0.05 and 0.97 +/- 0.07 l/min in hypoxia and hyperoxia, respectively) but did not improve with ADO-mediated vasodilation (0.80 +/- 0.09 l/min in hyperoxia + ADO). Although a vasodilatory reserve in the maximally working quadriceps muscle group may have been evidenced by increased leg vascular conductance after ADO infusion beyond that observed in hyperoxia (increased blood flow but no change in blood pressure), we recognize the possibility that the ADO infusion may have provoked vasodilation in nonexercising tissue of this limb. Together, these findings imply that maximally exercising skeletal muscle may maintain some vasodilatory capacity, but the lack of improvement in leg .VO(2 max) with significantly increased O(2) delivery (hyperoxia + ADO), with a degree of uncertainty as to the site of this dilation, suggests an ADO-induced mismatch between O(2) consumption and blood flow in the exercising limb.

  17. Applicability of an Indirect VO2max Test: Its Association with the 400 Meters Freestyle Performance

    Directory of Open Access Journals (Sweden)

    Adalberto Veronese da Costa

    Full Text Available Abstract The aim of this study was to evaluate the VO2max using a previously validated indirect test for non-expert adult swimmers and to verify its connection with the 400 meters freestyle test. A total of 17 non-expert male swimmers (21.5 ± 3.12 years were evaluated. Body composition measurements included body weight (74 ± 9.41 kg, height (172.9 ± 5.21 cm and body fat percentage (15.2 ± 4.15 %. Two tests were conducted on different days; the 400 meters freestyle (400 MF and the Progressive Swim Test (PSwT, respectively. The participant's heart rate frequency before and after the test (BHR and AHR was analyzed, as well as the subjective perception of effort (RPE, the number of laps covered (NLP, and the time of test execution measured in minutes. Significant differences were identified in all variables (p - 0.60 was found between AHR and execution time (r > - 0.70, as well as between the VO2max estimated by the PSwT and the 400 MF performance test (r > - 0.70. The Bland-Altman Plot showed that the values discovered were within the established concordance limits of 95% (±1.96 SD. A negative correlation between a swimming test and a test that estimates the VO2max occurred, and the PSwT showed results of greater approximation of the aerobic power of non-expert swimmers. In conclusion, the PSwT is applicable for non-expert adult swimmers.

  18. THE RELATIONSHIP BETWEEN AEROBIC POWER AND REPEATED SPRINT ABILITY IN YOUNG SOCCER PLAYERS WITH DIFFERENT LEVELS OF VO2 MAX

    Directory of Open Access Journals (Sweden)

    Rostam Alizadeh

    2010-06-01

    Full Text Available In some team sports such as soccer which is interval, athletes need to prepare themselves immediatelyfor the next activity. Therefore it is very important to have enough information on characteristics of recovery phase and quick recovery to the first situation and to have the minimum speed reduction. The purpose of this study was to determine the relationship between aerobic power and repeated sprint ability (RSA or decrementindex in young soccer players in three different levels of Vo2max. Methods: For this reason 41 volunteers were divided in to three groups with different levels of Vo2max ml.kg-1.min-1 low 37.22 ± 2.3 (n= 18, age 17.1 ± 0.9 year, height 170.6 ± 0.76 cm, weight 67.1 ± 5.05 kg medium 46.46± 1.97 ml.kg-1.min-1 (n= 13, age 17.6± 0.76year, height 173.8 ± 4.84 cm, weight 65.9 ± 4.92 kg and high 55.63 ± 1.52 ml.kg-1.min-1 (n=10, age 17.4 ±0.69 year, height 177 ± 3.23 cm, weight 71.4 ± 3.94 kg. To determine Vo2max a graded exercise test until volitional exhaustion on treadmill was used, and also RAST was used to measure RSA. The lactate accumulation was measured before and after RSA protocol. Pearson's correlation was used to determine the correlation between the aerobic power and RSA. The results indicated that there are significant relationship between Vo2max anddecremental index in low Vo2max group (r= 0.86, p= 0.001, no significant relationship medium Vo2max group (r= 0.14, p= 0.63 and negative significant relationship in high Vo2max group (r= - 0.64, p= 0.04. There are no significant relationship between Lactate accumulation and decremental index in medium (r= 0.005, p= 0.98 and high Vo2max groups (r=0.27, p= 0.45. Discussion: It is possible that the recovery of inter muscular resources relates to aerobic ability, but there are other factors effective in RSA rather than Vo2max and Lactate accumulation. The current study showed a normal curved relationship between Vo2max and RSA.

  19. VO2max Measured with a Self-selected Work Rate Protocol on an Automated Treadmill.

    Science.gov (United States)

    Scheadler, Cory M; Devor, Steven T

    2015-10-01

    The use of graded maximal exercise tests for measuring maximal oxygen consumption (VO2max) is common practice in both cardiopulmonary rehabilitation settings and in sports medicine research. Recent alterations of common testing protocols to allow for self-selected work rates (SPV) have elicited V˙O2max values similar to or higher than more traditional style protocols (TP). Research is lacking in the delivery of the SPV protocol using a treadmill modality. The purpose of the study was to examine the validity of an SPV using an automated treadmill for measuring cardiorespiratory fitness. Thirteen experienced endurance runners completed three maximal exercise tests on a treadmill. Oxygen consumption was measured using a computerized system and averaged more than 30-s time periods. SPV was completed using an automated treadmill that consisted of a sonar range finder, microcontroller, and customized computer software. Subject deviations from the middle of the treadmill belt resulted in rapid, graded increases or decreases in speed. TP was completed on the same treadmill without the use of the automated software. A verification phase protocol (VP) was used to verify if VO2 was maximal. Peak work rate achieved during SPV was significantly greater than that achieved during TP by 1.2 METs; P VO2max than TP despite higher work rates.

  20. Exercise tolerance during VO2max testing is a multifactorial psychobiological phenomenon.

    Science.gov (United States)

    Midgley, Adrian W; Earle, Keith; McNaughton, Lars R; Siegler, Jason C; Clough, Peter; Earle, Fiona

    2017-08-21

    Fifty-nine men completed a VO2max test and a questionnaire to establish reasons for test termination, perceived exercise reserve (difference between actual test duration and the duration the individual perceived could have been achieved if continued until physical limitation), and perception of verbal encouragement. Participants gave between 1 and 11 factors as reasons for test termination, including leg fatigue, various perceptions of physical discomfort, safety concerns, and achievement of spontaneously set goals. The two most common main reasons were leg fatigue and breathing discomfort, which were predicted by pre-to-post test changes in pulmonary function (p = 0.038) and explosive leg strength (p = 0.042; R(2) = 0.40). Median (interquartile range) perceived exercise reserve, was 45 (50) s. Two-thirds of participants viewed verbal encouragement positively, whereas one-third had a neutral or negative perception. This study highlights the complexity of exercise tolerance during VO2max testing and more research should explore these novel findings.

  1. Determinants of maximal oxygen uptake (VO2 max) in fire fighter testing.

    Science.gov (United States)

    Vandersmissen, G J M; Verhoogen, R A J R; Van Cauwenbergh, A F M; Godderis, L

    2014-07-01

    The aim of this study was to evaluate current daily practice of aerobic capacity testing in Belgian fire fighters. The impact of personal and test-related parameters on the outcome has been evaluated. Maximal oxygen uptake (VO2 max) results of 605 male fire fighters gathered between 1999 and 2010 were analysed. The maximal cardio respiratory exercise tests were performed at 22 different centres using different types of tests (tread mill or bicycle), different exercise protocols and measuring equipment. Mean VO2 max was 43.3 (SD = 9.8) ml/kg.min. Besides waist circumference and age, the type of test, the degree of performance of the test and the test centre were statistically significant determinants of maximal oxygen uptake. Test-related parameters have to be taken into account when interpreting and comparing maximal oxygen uptake tests of fire fighters. It highlights the need for standardization of aerobic capacity testing in the medical evaluation of fire fighters. Copyright © 2014 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  2. Estimation of Aerobic Capacity (VO2-max and Physical Work Capacity in Laborers

    Directory of Open Access Journals (Sweden)

    Sedeghe Hosseinabadi

    2013-06-01

    Full Text Available Introduction: Measurement of Maximum aerobic capacity (VO2-max is important in physiologically fitting the laborers to the job. This study was conducted to estimate the aerobic capacity and physical work capacity (PWC of workers of galvanize department of Semnan rolling pipe Company and also determine the relative frequency of workers whom their jobs were proportional to their physical work capacity . Methods: 50 male workers of Semnan rolling pipe company were selected randomly to participate in this cross-sectional study. Tuxworth & shahnavaz methods were applied to measure instances VO2-MAX. Independent-Sample t-test and correlation technique were used to analysis the data by SPSS software. Results: Average maximum aerobic capacity of workers was 2.88± .033 liters per minute and the average of physical work capacity was 4.76 ± 0.54 kilocalories per minute. There was a significant relationship between body mass index and aerobic capacity. The result showed that 36 percent of subjects expend more energy than their physical work capacity to perform their duties during the work time. Conclusion: According to the ILO classification, the average physical work capacity of the workers fall into a category of light energy;accordingly, on average, these workers had physical ability to performe less or lighter duties. More than one-third of these workers need to undergo job modification or to change their present job to a job with less energy consumption.

  3. The ergogenic effect of recombinant human erythropoietin on VO2max depends on the severity of arterial hypoxemia.

    Directory of Open Access Journals (Sweden)

    Paul Robach

    Full Text Available Treatment with recombinant human erythropoietin (rhEpo induces a rise in blood oxygen-carrying capacity (CaO(2 that unequivocally enhances maximal oxygen uptake (VO(2max during exercise in normoxia, but not when exercise is carried out in severe acute hypoxia. This implies that there should be a threshold altitude at which VO(2max is less dependent on CaO(2. To ascertain which are the mechanisms explaining the interactions between hypoxia, CaO(2 and VO(2max we measured systemic and leg O(2 transport and utilization during incremental exercise to exhaustion in normoxia and with different degrees of acute hypoxia in eight rhEpo-treated subjects. Following prolonged rhEpo treatment, the gain in systemic VO(2max observed in normoxia (6-7% persisted during mild hypoxia (8% at inspired O(2 fraction (F(IO(2 of 0.173 and was even larger during moderate hypoxia (14-17% at F(IO(2 = 0.153-0.134. When hypoxia was further augmented to F(IO(2 = 0.115, there was no rhEpo-induced enhancement of systemic VO(2max or peak leg VO(2. The mechanism highlighted by our data is that besides its strong influence on CaO(2, rhEpo was found to enhance leg VO(2max in normoxia through a preferential redistribution of cardiac output toward the exercising legs, whereas this advantageous effect disappeared during severe hypoxia, leaving augmented CaO(2 alone insufficient for improving peak leg O(2 delivery and VO(2. Finally, that VO(2max was largely dependent on CaO(2 during moderate hypoxia but became abruptly CaO(2-independent by slightly increasing the severity of hypoxia could be an indirect evidence of the appearance of central fatigue.

  4. Why is VO2 max after altitude acclimatization still reduced despite normalization of arterial O2 content?

    Science.gov (United States)

    Calbet, J A L; Boushel, R; Radegran, G; Sondergaard, H; Wagner, P D; Saltin, B

    2003-02-01

    Acute hypoxia (AH) reduces maximal O2 consumption (VO2 max), but after acclimatization, and despite increases in both hemoglobin concentration and arterial O2 saturation that can normalize arterial O2 concentration ([O2]), VO2 max remains low. To determine why, seven lowlanders were studied at VO2 max (cycle ergometry) at sea level (SL), after 9-10 wk at 5,260 m [chronic hypoxia (CH)], and 6 mo later at SL in AH (FiO2 = 0.105) equivalent to 5,260 m. Pulmonary and leg indexes of O2 transport were measured in each condition. Both cardiac output and leg blood flow were reduced by approximately 15% in both AH and CH (P VO2 max (4.1 +/- 0.3 l/min at SL) fell to 2.2 +/- 0.1 l/min in AH (P VO2 max after acclimatization despite normalization of arterial [O2] is explained by two circulatory effects of altitude: 1) failure of cardiac output to normalize and 2) preferential redistribution of cardiac output to nonexercising tissues. Oxygen transport from blood to muscle mitochondria, on the other hand, appears unaffected by CH.

  5. Is low VO2max/kg in obese heart failure patients indicative of cardiac dysfunction?

    Science.gov (United States)

    Hothi, S S; Tan, D K; Partridge, G; Tan, L B

    2015-04-01

    Low peak O2 consumption (VO2max/kg) has been widely used as an indirect indicator of poor cardiac fitness, and often guides management of patients with severe heart failure (HF). We hypothesized that it should be as good an indicator of cardiac dysfunction in obese and non-obese HF patients. We compared the cardiopulmonary exercise performance and non-invasive hemodynamics of 152 obese (BMI>34 kg.m(-2)) and 173 non-obese (BMI≤32) male HF patients in NYHA classes II and III, with reference to 101 healthy male controls. Their physical and cardiac functional reserves were measured during treadmill exercise testing with standard respiratory gas analyses and CO2 rebreathing to measure cardiac output non-invasively during peak exercise. Data are given as mean ± SD. Obese HF patients with BMI 40.9 ± 7.5 kg·m(-2) (age 56.1 ± 14.0 years, NYHA 2.5 ± 0.5) exercised to acceptable cardiopulmonary limits (peak RER=1.07 ± 0.12), and achieved a mean VO2max/kg of 18.6 ± 5.2 ml·kg(-1)·min(-1), significantly lower than in non-obese HF counterparts (19.9 ± 5.6 ml·kg(-1)·min(-1), P=0.02, age 55.8 ± 10.6 years, BMI 26.6 ± 3.1, NYHA 2.4 ± 0.5, peak RER=1.07 ± 0.09), with both lower than controls (38.5 ± 9.7 ml·kg(-1)·min(-1), PVO2max was higher in obese (2.31 ± 0.69 ml·min(-1)) than non-obese HF patients (1.61 ± 0.49 ml·min(-1), PVO2max/kg is not a generally reliable indicator of cardiac fitness in all patients. Instead, we found that despite having lower VO2max/kg, obese HF patients had stronger hearts capable of generating greater cardiac power than non-obese HF patients of equivalent clinical HF status. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  6. Continuos incremental field test to estimate velocity and maximal oxygen consumption in non-expert runners

    OpenAIRE

    José A. Bragada; Moreno, R; Barbosa, Tiago M

    2009-01-01

    Parameters such as a maximal oxygen uptake (VO2max) and velocity at which VO2max occurs (VelVO2max) are often used to training control purposes to enhance runner’s performance. This study had two purposes: (i) determine the relationship between VelVO2max obtained in continuous incremental filed test (CIFT) and VelVO2max determined on a treadmill in a laboratory; and (II) verify if it is possible to estimate the VO2max based on CIFT velocity

  7. [Expired gas analysis--focused on VO2 max and anaerobic threshold].

    Science.gov (United States)

    Omiya, K

    1996-07-01

    Recently, expired gas analysis(EGA) during exercise testing is broadly performed. It has been recognized that anaerobic threshold(AT) and maximal oxygen uptake(VO2 max) may be useful in identifying one's exercise tolerance. AT especially has a good correlation with endurance capacity. In the field of sports medicine, the purposes of EGA are: 1) evaluation of endurance exercise capacity. 2) decision of intensity and frequency for exercise training, and 3) prevention of overtraining syndrome. In the clinical fields, EGA is frequently performed with cardiovascular patients, for example, myocardial infarction(MI), and congestive heart failure(CHF). The purposes are: 1) decision of intensity for exercise therapy with the patients of old MI. 2) evaluation of exercise capacity with the patients' of CHF. 3) index of exercise therapy for hypertension, hyperlipidemia, and diabetes, and 4) evaluation of drug effects including vasodilators and cardiotonics.

  8. Ratio of total carbon dioxide produced to oxygen consumed is predictive of VO2 max during graded exercise testing

    Directory of Open Access Journals (Sweden)

    DAVID BELLAR

    2016-10-01

    Full Text Available The purpose of the present investigation was to examine the ratio between total cO2 expiration and O2 consumption to vO2max. Twenty-six male (vO2 max: 55.4± 8.3 ml O2/kg*min and thirty- five female (vO2 max: 44.1± 8.1 ml O2/kg*min recreationally active adults volunteered. The participants underwent a custom ramped treadmill protocol (gXT with expired gases monitored. Third order polynomial regression was undertaken for the vO2 and vcO2 by time (r>0.950. regression equations were integrated from 60seconds after the start of the test (to negate any initial hyperventilation until vO2 max. This area under the curve calculation was equal to the total accumulated expired cO2 and consumed O2. The ratio of total cO2 to O2 was calculated (auc ratio. Data analysis was undertaken using multiple linear regression analysis. The model included gender, rer at vO2 max and auc ratio as predictors and relative vO2 max as the outcome. The model was significant with predictor variable gender (b =0.582, p<0.001 and auc ratio (b=-0.298, p=0.019 significant in the model. Based upon these results it would appear that individuals who are more fit relying more heavily on oxidative pathways throughout the course of a GXT.

  9. The ergogenic effect of recombinant human erythropoietin on VO2max depends on the severity of arterial hypoxemia

    DEFF Research Database (Denmark)

    Robach, Paul; Calbet, Jose A L; Thomsen, Jonas J;

    2008-01-01

    Treatment with recombinant human erythropoietin (rhEpo) induces a rise in blood oxygen-carrying capacity (CaO(2)) that unequivocally enhances maximal oxygen uptake (VO(2)max) during exercise in normoxia, but not when exercise is carried out in severe acute hypoxia. This implies that there should...... redistribution of cardiac output toward the exercising legs, whereas this advantageous effect disappeared during severe hypoxia, leaving augmented CaO(2) alone insufficient for improving peak leg O(2) delivery and VO(2). Finally, that VO(2)max was largely dependent on CaO(2) during moderate hypoxia but became...

  10. Graded Exercise Testing Protocols for the Determination of VO2max: Historical Perspectives, Progress, and Future Considerations.

    Science.gov (United States)

    Beltz, Nicholas M; Gibson, Ann L; Janot, Jeffrey M; Kravitz, Len; Mermier, Christine M; Dalleck, Lance C

    2016-01-01

    Graded exercise testing (GXT) is the most widely used assessment to examine the dynamic relationship between exercise and integrated physiological systems. The information from GXT can be applied across the spectrum of sport performance, occupational safety screening, research, and clinical diagnostics. The suitability of GXT to determine a valid maximal oxygen consumption (VO2max) has been under investigation for decades. Although a set of recommended criteria exists to verify attainment of VO2max, the methods that originally established these criteria have been scrutinized. Many studies do not apply identical criteria or fail to consider individual variability in physiological responses. As an alternative to using traditional criteria, recent research efforts have been directed toward using a supramaximal verification protocol performed after a GXT to confirm attainment of VO2max. Furthermore, the emergence of self-paced protocols has provided a simple, yet reliable approach to designing and administering GXT. In order to develop a standardized GXT protocol, additional research should further examine the utility of self-paced protocols used in conjunction with verification protocols to elicit and confirm attainment of VO2max.

  11. Impact of Body Composition and Vo2 Max on the Competitive Success in Top-Level Handball Players.

    Science.gov (United States)

    Ilic, Vladimir; Ranisavljev, Igor; Stefanovic, Dorde; Ivanovic, Vuk; Mrdakovic, Vladimir

    2015-09-01

    The purpose of the study was to determine the morphological and functional characteristics of 32 Serbian national U20 handball players (age 20.43 +/- 1.16 y; training experience 8.12 +/- 1.89 y) before European championship in Switzerland (2006) and to determinate their impact on competitive performance and outstanding success achieved. The results show that wing players differ from other players in morphological characteristics. Values for body height, weight, BMI, muscle mass and fat mass were significantly lower compared to the other playing positions. Extremely low values of maximal oxygen uptake (VO2 max) were measured in all players (ranged from 2.68 to 4.66 l x min(-1)). Pivots had the highest VO2 max in absolute values (3.76 l x min(-1)), and wing players in relative terms (40.83 ml x kg(-1) x min(-1)). Handball is characterized by high intensity intermittent play, followed by a number of walking breaks and quick substitutions. This makes possible to retain high playing intensity during whole match, because players can be given rest periods whenever needed. This will result in a high intensity game that does not necessarily require high VO2 max. Competitive success in modern top-level handball might be more reliant on optimal tactical preparation than on the body composition and VO2 max of an individual athlete.

  12. Graded Exercise Testing Protocols for the Determination of VO2max: Historical Perspectives, Progress, and Future Considerations

    Directory of Open Access Journals (Sweden)

    Nicholas M. Beltz

    2016-01-01

    Full Text Available Graded exercise testing (GXT is the most widely used assessment to examine the dynamic relationship between exercise and integrated physiological systems. The information from GXT can be applied across the spectrum of sport performance, occupational safety screening, research, and clinical diagnostics. The suitability of GXT to determine a valid maximal oxygen consumption (VO2max has been under investigation for decades. Although a set of recommended criteria exists to verify attainment of VO2max, the methods that originally established these criteria have been scrutinized. Many studies do not apply identical criteria or fail to consider individual variability in physiological responses. As an alternative to using traditional criteria, recent research efforts have been directed toward using a supramaximal verification protocol performed after a GXT to confirm attainment of VO2max. Furthermore, the emergence of self-paced protocols has provided a simple, yet reliable approach to designing and administering GXT. In order to develop a standardized GXT protocol, additional research should further examine the utility of self-paced protocols used in conjunction with verification protocols to elicit and confirm attainment of VO2max.

  13. Graded Exercise Testing Protocols for the Determination of VO2max: Historical Perspectives, Progress, and Future Considerations

    Science.gov (United States)

    Gibson, Ann L.; Janot, Jeffrey M.; Kravitz, Len; Dalleck, Lance C.

    2016-01-01

    Graded exercise testing (GXT) is the most widely used assessment to examine the dynamic relationship between exercise and integrated physiological systems. The information from GXT can be applied across the spectrum of sport performance, occupational safety screening, research, and clinical diagnostics. The suitability of GXT to determine a valid maximal oxygen consumption (VO2max) has been under investigation for decades. Although a set of recommended criteria exists to verify attainment of VO2max, the methods that originally established these criteria have been scrutinized. Many studies do not apply identical criteria or fail to consider individual variability in physiological responses. As an alternative to using traditional criteria, recent research efforts have been directed toward using a supramaximal verification protocol performed after a GXT to confirm attainment of VO2max. Furthermore, the emergence of self-paced protocols has provided a simple, yet reliable approach to designing and administering GXT. In order to develop a standardized GXT protocol, additional research should further examine the utility of self-paced protocols used in conjunction with verification protocols to elicit and confirm attainment of VO2max. PMID:28116349

  14. Knee extensor fatigue threshold is related to whole-body VO2max.

    Science.gov (United States)

    de Ruiter, Cornelis J; Maas, Ellen A; Wesseling, Mariska G H; de Haan, Arnold

    2012-07-01

    Above a given exercise intensity, rapid muscle fatigue will occur. We explored the possibility of assessing torque threshold for peripheral fatigue during single-legged repetitive isometric knee extensor exercise. We hypothesized this fatigue threshold to be related to the general aerobic fitness level and the so-called "critical torque" (CT) established with a recently validated 5-min all-out test. Seventeen healthy men (VO(2max) = 44.7-69.6 mL·kg(-1)·min(-1)) performed six submaximal (20%-55% maximal voluntary contraction [MVC]) 5-min bouts of 60 repetitive contractions (3-s on, 2-s off). Torque was changed between bouts in steps of 5% MVC to estimate the highest intensity (fatigue threshold) at which average changes in rsEMG, EMG median power frequency, and tissue deoxygenation (near-infrared spectroscopy) of the three superficial knee extensor muscles were still test torque representing CT. Fatigue threshold (40.0% ± 8.1% MVC) was related (r(2) = 0.57, P test may be used to evaluate changes in endurance capacity of single muscle groups, without the necessity for all-out testing, which could be problematic with frail subjects.

  15. Aerobic Fitness Levels and Validation of a Non-Exercise VO2max Prediction Equation for HIV-Infected Patients on HAART

    Science.gov (United States)

    Sullivan, Katherine; Shikuma, Cecilia M.; Chow, Dominic; Cornelius, Elizabeth; Romine, Rebecca K.; Lindsey, Rachel A.; Stickley, Christopher D.; Kimura, Iris F.; Hetzler, Ronald K.

    2015-01-01

    Background Non-exercise (N-EX) questionnaires have been developed to determine maximal oxygen consumption (VO2max) in healthy populations. There are limited reliable and validated N-EX questionnaires for the HIV+ population that provide estimates of habitual physical activity and not VO2max. Objectives To determine how well regression equations developed previously on healthy populations, including N-EX prediction equations for VO2max and age-predicted maximal heart rates (APMHR), worked on an HIV+ population; and to develop a specific N-EX prediction equation for VO2max and APMHR for HIV+ individuals. Methods Sixty-six HIV+ participants on stable HAART completed 4 N-EX questionnaires and performed a maximal graded exercise test. Results Sixty males and 6 females were included; mean (SD) age was 49.2 (8.2) years; CD4 count was 516.0 ± 253.0 cells·mn−3; and 92% had undetectable HIV PCR. Mean VO2max was 29.2 ± 7.6 (range, 14.4–49.4) mL·kg−1·min−1. Despite positive correlations with VO2max, previously published N-EX VO2max equations produced results significantly different than actual VO2 scores (P VO2max values, R = 0.71, when compared to achieved VO2max (P = .53). Conclusion HIV+ individuals tend to be sedentary and unfit, putting them at increased risk for the development of chronic diseases associated with a sedentary lifestyle. Based on the level of error associated with utilizing APMHR and N-EX VO2max equations with HIV+ individuals, neither should be used in this population for exercise prescription. PMID:24710921

  16. A Reference Equation for Normal Standards for VO2 max: Analysis from the Fitness Registry and the Importance of Exercise National Database (FRIEND Registry).

    Science.gov (United States)

    Myers, Jonathan; Kaminsky, Leonard A; Lima, Ricardo; Chistle, Jeffrey; Ashley, Euan; Arena, Ross

    2017-04-01

    Existing normal standards for maximal oxygen uptake (VO2 max) are problematic because they tend to be population specific, lack normal distribution and portability, and are poorly represented by women. The objective of the current study was to apply the Fitness Registry and the Importance of Exercise: A National Data Base (FRIEND) Registry to improve upon previous regression formulas for normal standards for VO2 max using treadmill testing. Maximal treadmill tests were performed in 7783 healthy men and women (20-79years; maximal RER >1.0) from the FRIEND registry and a separate validation cohort of 1287 subjects. A regression equation for VO2 max was derived from the FRIEND registry and compared to the validation cohort and two commonly used equations (Wasserman and European). Age, gender, and body weight were the only significant predictors of VO2 max (multiple R=0.79, R(2)=0.62, p<0.001). The equation for predicting VO2 max was: [Formula: see text] Marked differences were observed in percentage predicted VO2 max achieved between commonly used reference equations, particularly among women, overweight and obese subjects. In the validation sample, the FRIEND equation closely paralleled measured VO2 max, with the validation group yielding a percent predicted VO2 max of 100.4% based on the FRIEND equation. An equation for age-predicted VO2 max derived from the FRIEND registry provided a lower average error between measured and predicted VO2 max than traditional equations, and thus may provide a more suitable normal standard relative to traditional equations.

  17. Specificity of VO2MAX and the ventilatory threshold in free swimming and cycle ergometry: comparison between triathletes and swimmers.

    Science.gov (United States)

    Roels, B; Schmitt, L; Libicz, S; Bentley, D; Richalet, J-P; Millet, G

    2005-12-01

    To compare maximal heart rate (HRmax), maximal oxygen consumption (VO2MAX), and the ventilatory threshold (VT; %VO2MAX) during cycle ergometry and free swimming between swimmers and triathletes. Nine swimmers and ten triathletes completed an incremental swimming and cycling test to exhaustion. Whole body metabolic responses were determined in each test. The swimmers exhibited a significantly higher VO2MAX in swimming than in cycling (58.4 (5.6) v 51.3 (5.1) ml/kg/min), whereas the opposite was found in the triathletes (53.0 (6.7) v 68.2 (6.8) ml/kg/min). HRmax was significantly different in the maximal cycling and swimming tests for the triathletes (188.6 (7.5) v 174.8 (9.0) beats/min). In the maximal swimming test, HRmax was significantly higher in the swimmers than in the triathletes (174.8 (9.0) v 184.6 (9.7) beats/min). No significant differences were found for VT measured in swimming and cycling in the triathletes and swimmers. This study confirms that the exercise testing mode affects the VO2MAX value, and that swimmers have very specific training adaptations even compared with triathletes. This may be a function of acute physiological responses combined with the specialist training status of the different athletes influencing maximal cardiac output or oxygen extraction. In contrast, the different training regimens do not seem to influence the VT, as this variable did not differ between the two testing modes in either group.

  18. The reliability and validity of the Astrand nomogram and linear extrapolation for deriving VO2max from submaximal exercise data.

    Science.gov (United States)

    Macsween, A

    2001-09-01

    While the accepted measure of aerobic power remains the VO2max this test is extremely demanding even for athletes. There are serious practical and ethical concerns in attempting such testing in non-athletic or patient populations. An alternative method of measuring aerobic power in such populations is required. A limited body of work exists evaluating the accuracy of the Astrand-Ryhming nomogram and linear extrapolation of the heart rate/oxygen uptake plot. Issues exist in terms of both equipment employed and sample numbers. Twenty-five normal subjects (mean age 28.6, range 22-50) completed 52 trials (Bruce treadmill protocol) meeting stringent criteria for VO2max performance. Respiratory gases were measured with a portable gas analyser on a five-sec sample period. The data was analysed to allow comparison of the reliability and validity of linear extrapolations to three estimates of heart rate maximum with the Astrand nomogram prediction. Extrapolation was preferable yielding intraclass correlation co-efficients (ICC) of 0.9433 comparable to that of the observed VO2max at 0.9443 and a bias of -1.1 ml x min(-1) x kg(-1) representing a 2.19 percent underestimate. This study provides empirical evidence that extrapolation of submaximal data can be employed with confidence for both clinical monitoring and research purposes. With the use of portable equipment and submaximal testing the scope for future research in numerous populations and non-laboratory environments is considerably increased.

  19. Efeito da intensidade do exercício de corrida intermitente 30s:15s no tempo de manutenção no ou próximo do VO2max

    OpenAIRE

    Aguiar,Rafael Alves de; Schlickmann, Jardel; Turnes, Tiago; Caputo, Fabrizio [UNESP

    2013-01-01

    O presente estudo comparou o tempo mantido acima de 90% (t90VO2max) e de 95% VO2max (t95VO2max) em três diferentes intensidades de exercício. Após a realização de um teste incremental para determinar o VO2max, oito estudantes de educação física ativos (23 ± 3 anos) executaram três sessões de exercícios intermitentes (100, 110 e 120% da velocidade do VO2max (vVO2max)) com razão esforço:recuperação de 30s:15s. O t95VO2max foi significantemente maior em 110%vVO2max (EI110%) (218,1 ± 81,6 s) quan...

  20. Influence of an Enforced Fast Start on 10-km-Running Performance.

    Science.gov (United States)

    do Carmo, Everton C; Barroso, Renato; Renfree, Andrew; Gil, Saulo; Tricoli, Valmor

    2016-09-01

    The effects of an enforced fast start on long-distance performance are controversial and seem to depend on the athlete's capacity to delay and tolerate metabolic disruption. The aim of this study was to investigate the effects of an enforced start on 10-km-running performance and the influence of the some physiological and performance variables on the ability to tolerate an enforced fast start during the running. Fifteen moderately trained runners performed two 10-km time trials (TTs): free pacing (FP-TT) and fast start (FS-TT). During FS-TT, speed during the first kilometer was 6% higher than in FP-TT. Maximal oxygen uptake (VO2max), peak velocity (PV), velocity associated with VO2max (vVO2max), ventilatory threshold, and running economy at 10 and 12 km/h and FP-TT average velocity (AV-10 km) were individually determined. There were no differences between FP-TT and FS-TT performance (45:01 ± 4:08 vs 45:11 ± 4:46 min:s, respectively, P = .4). Eight participants improved (+2.2%) their performance and were classified as positive responders (PR) and 7 decreased (-3.3%) performance and were classified as negative responders (NR). Running speed was significantly higher for PR between 6 and 9.2 km (P performance also presented higher vVO2max and PV, suggesting a possible association between these variables and response to the strategy adopted.

  1. Evidence of O2 supply-dependent VO2 max in the exercise-trained human quadriceps.

    Science.gov (United States)

    Richardson, R S; Grassi, B; Gavin, T P; Haseler, L J; Tagore, K; Roca, J; Wagner, P D

    1999-03-01

    Maximal O2 delivery and O2 uptake (VO2) per 100 g of active muscle mass are far greater during knee extensor (KE) than during cycle exercise: 73 and 60 ml. min-1. 100 g-1 (2.4 kg of muscle) (R. S. Richardson, D. R. Knight, D. C. Poole, S. S. Kurdak, M. C. Hogan, B. Grassi, and P. D. Wagner. Am. J. Physiol. 268 (Heart Circ. Physiol. 37): H1453-H1461, 1995) and 28 and 25 ml. min-1. 100 g-1 (7.5 kg of muscle) (D. R. Knight, W. Schaffartzik, H. J. Guy, R. Predilleto, M. C. Hogan, and P. D. Wagner. J. Appl. Physiol. 75: 2586-2593, 1993), respectively. Although this is evidence of muscle O2 supply dependence in itself, it raises the following question: With such high O2 delivery in KE, are the quadriceps still O2 supply dependent at maximal exercise? To answer this question, seven trained subjects performed maximum KE exercise in hypoxia [0.12 inspired O2 fraction (FIO2)], normoxia (0.21 FIO2), and hyperoxia (1.0 FIO2) in a balanced order. The protocol (after warm-up) was a square wave to a previously determined maximum work rate followed by incremental stages to ensure that a true maximum was achieved under each condition. Direct measures of arterial and venous blood O2 concentration in combination with a thermodilution blood flow technique allowed the determination of O2 delivery and muscle VO2. Maximal O2 delivery increased with inspired O2: 1.3 +/- 0.1, 1.6 +/- 0.2, and 1.9 +/- 0.2 l/min at 0.12, 0.21, and 1.0 FIO2, respectively (P VO2 (VO2 max): 1.04 +/- 0.13, 1. 24 +/- 0.16, and 1.45 +/- 0.19 l/min at 0.12, 0.21, and 1.0 FIO2, respectively (P VO2 max, supporting our previous finding that a decrease in O2 supply will proportionately decrease muscle VO2 max. As even in the isolated quadriceps (where normoxic O2 delivery is the highest recorded in humans) an increase in O2 supply by hyperoxia allows the achievement of a greater VO2 max, we conclude that, in normoxic conditions of isolated KE exercise, KE VO2 max in trained subjects is not limited by mitochondrial

  2. Correlação entre as medidas direta e indireta do VO2max em atletas de futsal Correlación entre las medidas directa e indirecta del VO2max en atletas de futsal Correlation between direct and indirect VO2max measurements in indoor soccer players

    Directory of Open Access Journals (Sweden)

    Anna Myrna Jaguaribe de Lima

    2005-06-01

    Full Text Available A importância das qualidades morfofuncionais na melhora do rendimento nos esportes aumentou o interesse no aprimoramento dos níveis de aptidão física dos atletas. No entanto, há poucos estudos sobre as variáveis fisiológicas do futsal disponíveis na literatura científica mundial. Dessa forma, o objetivo deste estudo foi verificar a existência de correlação entre os testes de medida direta e indireta do VO2max, em jogadores de futsal. Foram analisados 13 jogadores de futsal, com idade de 18,6 ± 1,9 anos, altura igual a 177,1 ± 3,5cm, peso de 68,5 ± 9,5kg, índice de massa corporal (IMC de 21,7 ± 2,3kg/m². Para medida direta do VO2max foi utilizado o sistema ergoespirométrico computadorizado (VO-2000, Aerosport, Medgraphics, St. Paul, Minnesota e para mensuração indireta do VO2max foi realizado o teste de campo de 3.200m. A análise estatística foi elaborada através do teste t de Student para amostras pareadas e pelo coeficiente de correlação de Pearson. Os valores de VO2max obtidos no teste de medida direta não apresentaram diferenças significativas em relação à medida indireta (62,8 ± 10,1 vs. 58,5 ± 8,5ml/kg/min, respectivamente. Quando correlacionados os valores de VO2max obtidos em ambos os testes, observou-se forte correlação (r = 0,72. Em conclusão, os testes de medida indireta apresentam boa aceitação para os atletas de futsal, tendo em vista a alta correlação com os testes de medida direta, o baixo custo de sua aplicação e o fornecimento de informações importantes que podem auxiliar na prescrição e no acompanhamento do treinamento.La importância de las cualidades morfo-funcionales en la mejora del rendimiento en los deportes aumentó el interes en el acondicionamiento de los niveles de aptitud física de los atletas. En tanto, hay pocos estudios sobre las variables fisiológicas del futsal disponibles en la literatura mundial. De esta forma, el objetivo del estudio fué verificar la existencia

  3. The role of haemoglobin mass on VO(2)max following normobaric 'live high-train low' in endurance-trained athletes

    DEFF Research Database (Denmark)

    Robach, Paul; Siebenmann, Christoph; Jacobs, Robert A

    2012-01-01

    It remains unclear by which mechanism 'live high-train low' (LHTL) altitude training increases exercise performance. Haematological and skeletal muscle adaptations have both been proposed. To test the hypotheses that (i) LHTL improves maximal oxygen uptake (VO(2)max) and (ii) this improvement...... is related to hypoxia-induced increases in total haemoglobin mass (Hb(mass)) and not to improved maximal oxidative capacity of skeletal muscle, we determined VO(2)max before LHTL and after LHTL, before and after the altitude-induced increases in Hb(mass) (measured by carbon-monoxide rebreathing) had been...... to 3000 m altitude (LHTL, n=10). Four-week LHTL did not increase VO(2)max, irrespective of treatment (LHTL: 1.5%; placebo: 2.0%). Hb(mass) was slightly increased (4.6%) in 5 (of 10) LHTL subjects but this was not accompanied by a concurrent increase in VO(2)max. In the subjects demonstrating an increase...

  4. Concurrent validity of the non-exercise based VO2max prediction equation using percentage body fat as a variable in asian Indian adults

    Science.gov (United States)

    2012-01-01

    Background Aerobic capacity (VO2max) is highly dependent upon body composition of an individual and body composition varies with ethnicity. The purpose of this study was to check the concurrent validity of the non-exercise prediction equation developed by Jackson and colleagues (1990) using percentage body fat as a variable in Asian Indian adults. Methods One hundred twenty college-aged participants (60 male, 60 female, mean age 22.02 ± 2.29 yrs) successfully completed a maximal graded exercise test (GXT) on a motorized treadmill to assess VO2max. VO2max was then estimated by the non-exercise prediction equation developed by Jackson and colleagues (1990) using percentage body fat. Percentage body fat was calculated by three different models (Sandhu et al’s fat mass equation, Durnin-womersley’s 4 site percentage body fat and Jackson & Pollock’s 4 site percentage body fat) and was used in the above equation. The results of VO2max obtained using “gold standard” treadmill methods were then compared with the three results of VO2max obtained by Jackson et al’s equation (using three different models to calculate percentage body fat) and it was determined which equation is best suited to determine percentage body fat and in turn VO2 max for Indian population. Results Jackson et al’s prediction equation overpredicts VO2max in Asian Indian subjects who have a lower VO2max (33.41 ± 14.39 ml/kg/min) than those reported in other age matched populations. percentage body fats calculated by the three equations were significantly different and the correlation coefficient (r) between VO2max calculated by Jackson and colleagues (1990) using Sandhu et al’s equation for percentage body fat with VO2 max calculated using treadmill (gold standard) (r = .817) was found slightly more significantly correlated than the other two equations and was not statistically different from the measured value. Conclusions This study proves that VO2max equation using

  5. The effect of limited handrail support on total treadmill time and the prediction of VO2 max.

    Science.gov (United States)

    Manfre, M J; Yu, G H; Varmá, A A; Mallis, G I; Kearney, K; Karageorgis, M A

    1994-08-01

    Holding onto the front handrail during treadmill testing significantly increases total treadmill time (TT) and predicted VO2max when compared with tests without front handrail support. By limiting the amount of handrail support to the tips of two fingers of one hand, the difference in TT can be substantially reduced. In the present study, the difference in TT between tests with and without handrail support for healthy men was not significantly different. However, this was not true for healthy women and for male patients with coronary artery disease and myocardial infarction.

  6. Oxygen uptake and blood metabolic responses to a 400-m run.

    Science.gov (United States)

    Hanon, Christine; Lepretre, Pierre-Marie; Bishop, David; Thomas, Claire

    2010-05-01

    This study aimed to investigate the oxygen uptake and metabolic responses during a 400-m run reproducing the pacing strategy used in competition. A portable gas analyser was used to measure the oxygen uptake (VO2) of ten specifically trained runners racing on an outdoor track. The tests included (1) an incremental test to determine maximal VO2 (VO2max) and the velocity associated with VO2(max) (v - VO2max), (2) a maximal 400-m (400T) and 3) a 300-m running test (300T) reproducing the exact pacing pattern of the 400T. Blood lactate, bicarbonate concentrations [HCO3(-)], pH and arterial oxygen saturation were analysed at rest and 1, 4, 7, 10 min after the end of the 400 and 300T. The peak VO2 recorded during the 400T corresponded to 93.9 +/- 3.9% of VO2max and was reached at 24.4 +/- 3.2 s (192 +/- 22 m). A significant decrease in VO2 (P < 0.05) was observed in all subjects during the last 100 m, although the velocity did not decrease below v - VO2max. The VO2 in the last 5 s was correlated with the pH (r = 0.86, P < 0.0005) and [HCO3(-)] (r = 0.70, P < 0.05) measured at the end of 300T. Additionally, the velocity decrease observed in the last 100 m was inversely correlated with [HCO3(-)] and pH at 300T (r = -0.83, P < 0.001, r = -0.69, P < 0.05, respectively). These track running data demonstrate that acidosis at 300 m was related to both the VO2 response and the velocity decrease during the final 100 m of a 400-m run.

  7. The impact of decreasing cutoff values for maximal oxygen consumption (VO2max) in the decision-making process for candidates to lung cancer surgery

    Science.gov (United States)

    Gatani, Tindaro; Di Maio, Massimo; Meoli, Ilernando; La Rocca, Antonello; Martucci, Nicola; La Manna, Carmine; Stefanelli, Francesco

    2013-01-01

    Background Maximal oxygen consumption (VO2max) is considered a decisive test for risk prediction in patients with borderline cardiopulmonary reserve. Guidelines have adopted decreasing VO2max cut-off values to define operability within acceptable mortality and morbidity limits. We wanted to investigate how the adoption of decreasing VO2max cut-off-values assessment contributed to better select lung surgery candidates. Methods One hundred and nineteen consecutive surgical candidates have been prospectively analyzed as a sample population. Preoperative work-up included spirometry and transfer factor (DLco); irrespective of the spirometric values, these patients were subjected to VO2max assessment. Surgical eligibility was decided by the same surgeon throughout the series. In the postoperative period, overall mortality and the occurrence of any, major or minor complications was recorded and graded according to the Common Terminology Criteria for Adverse Events v.4.3. Results Three arbitrary cut-offs were introduced at 15, 14 and 12 mL.kg-1.min-1. Notably, 15 and 12 mL.kg-1.min-1 correlated with percentage VO2max values of 50% and 35% of predicted (PVO2max less than 35% (P=0.0017) and CTCAE >2 (P=0.0457) emerged as significant predictors of survival after surgery. Conversely on logistic regression analysis, age over 70 years (P=0.03) and pneumonectomy (P=0.001), but not VO2max cut-off values, were significant predictors of major (CTCAE >2) morbidity. Conclusions Since VO2max is increasingly used to contribute to risk prediction for the individual patient, surgeons need to be advised that the concept of a definitive, generalized cut-off value for VO2max is probably a contradiction in terms. Patient-specific VO2max values are more likely to contribute to risk assessment since they may reflect the primarily affected component among the determinants of maximal oxygen consumption. Whether patient-specific VO2max should be routinely used by surgeons to define operability for

  8. Strength training improves cycling performance, fractional utilization of VO2max and cycling economy in female cyclists.

    Science.gov (United States)

    Vikmoen, O; Ellefsen, S; Trøen, Ø; Hollan, I; Hanestadhaugen, M; Raastad, T; Rønnestad, B R

    2016-04-01

    The purpose of this study was to investigate the effect of adding heavy strength training to well-trained female cyclists' normal endurance training on cycling performance. Nineteen female cyclists were randomly assigned to 11 weeks of either normal endurance training combined with heavy strength training (E+S, n = 11) or to normal endurance training only (E, n = 8). E+S increased one repetition maximum in one-legged leg press and quadriceps muscle cross-sectional area (CSA) more than E (P < 0.05), and improved mean power output in a 40-min all-out trial, fractional utilization of VO2 max and cycling economy (P < 0.05). The proportion of type IIAX-IIX muscle fibers in m. vastus lateralis was reduced in E+S with a concomitant increase in type IIA fibers (P < 0.05). No changes occurred in E. The individual changes in performance during the 40-min all-out trial was correlated with both change in IIAX-IIX fiber proportion (r = -0.63) and change in muscle CSA (r = 0.73). In conclusion, adding heavy strength training improved cycling performance, increased fractional utilization of VO2 max , and improved cycling economy. The main mechanisms behind these improvements seemed to be increased quadriceps muscle CSA and fiber type shifts from type IIAX-IIX toward type IIA.

  9. Efeitos do estado e especificidade do treinamento aeróbio na relação %VO2max versus %FCmax durante o ciclismo Effects of the state and specificity of aerobic training on the %VO2max versus %HRmax ratio during cycling

    Directory of Open Access Journals (Sweden)

    Fabrizio Caputo

    2005-01-01

    Full Text Available OBJETIVO: Determinar os efeitos do estado e especificidade de treinamento aeróbio na relação entre o percentual do consumo máximo de oxigênio (%VO2max e o percentual da frequência cardíaca máxima (%FCmax durante o exercício incremental realizado no cicloergômetro. MÉTODOS: Sete corredores, 9 ciclistas, 11 triatletas e 12 sedentários, todos do sexo masculino e aparentemente saudáveis, foram submetidos a um teste incremental até a exaustão no cicloergômetro. Regressões lineares entre %VO2max e %FCmax foram determinadas para cada indivíduo. Com base nessas regressões, foram calculados %FCmax correspondentes a determinados %VO2max (50, 60, 70, 80 e 90% de cada participante. RESULTADOS: Não foram encontradas diferenças significantes entre todos os grupos nos %FCmax para cada um dos %VO2max avaliados. Analisando-se os voluntários como um único grupo, as médias dos %FCmax correspondentes a 50, 60, 70, 80 e 90% %VO2max foram 67, 73, 80, 87, e 93%, respectivamente. CONCLUSÃO: Nos grupos analisados, a relação entre o %VO2max e %FCmax durante o exercício incremental no ciclismo não é dependente do estado e especificidade do treinamento aeróbio.OBJECTIVE: To determine the effects of the status and specificity of exercise training in the ratio between maximum oxygen consumption (%VO2max and the percentage of maximal heart rate (%HRmax during incremental exercise on a cycle ergometer. METHODS: Seven runners, 9 cyclists, 11 triathletes, and 12 sedentary individuals, all male and apparently healthy, underwent exhaustive incremental exercise on cycle ergometers. Linear regressions between %VO2max x %HRmax were determined for each individual. Based on these regressions, %HRmax was assessed corresponding to a determined %VO2max (50, 60, 70, 80, and 90% from each participant. RESULTS: Significant differences were not found between the groups in %HRmax for each of the %VO2max assessed. Analyzing the volunteers as a single group, the

  10. The effect of acute L-Carnitine supplementation on the blood lactate, glucose, VO2max and power in trained men: a brief report

    Directory of Open Access Journals (Sweden)

    Arazi H

    2013-04-01

    Full Text Available Background: Probably L-Carnitine can induce increasing of Pyruvate dehydrogenase activity, decreasing of lactic acid production and performance improvements due to the reinforcement of long chain fatty acid oxidation and stabilize of Coenzyme A (CoASH to free Coenzyme A (COA. Based on this, the aim of this study was to investigate the effect of acute L-Carnitine supplementation on blood lactate, glucose, VO2max and anaerobic power in trained men.Methods: Sixteen trained men (aged 19-23 volunteers from University of Guilan, facul-ty of Physical Education and Sport Sciences participated as subjects in this investiga-tion. Subjects divided to aerobic (A and anaerobic (An group randomly. In a double blind design, subjects participated in two separated tests by one week. Subjects ingested 3 grams of L-Carnitine supplementation or placebo (maltodextrin 90 minute before aerobic and anaerobic exercise. For aerobic activity used shuttle run 20 meter and for anaerobic activity used RAST test. Blood samples were collected 5 minute prior at rest and 4 minute post tests. Participants were asked in the morning to obtain fasting blood samples and perform tests. A t-test was used to detect differences between supplementa-tion and placebo groups in each exercise.Results: L-Carnitine group ((A 141.25±20.62 and (An 145.38±55.47 significantly had lower lactate concentration than placebo ((A 151.00±20.85 and (An 152.50±28.59 after tests (P≤0.05. L-Carnitine group ((A 136.00±19.74 and (An 115.50±13.64 had significa-ntly higher blood glucose compared to placebo ((A 121.62±15.65 and (An 110.12±12.63 too (P≤0.05. Also, VO2max, mean and maximum anaerobic power in L-Carnitine group were significantly more than ones in placebo (P<0.05.Conclusion: These findings indicate that acute oral supplementation of L-Carnitine can induce fatigue decreasing and improvement of aerobic and anaerobic performance.

  11. Influência do estado nutricional e do VO2max nos níveis de adiponectina em homens acima de 35 anos Influencia del Estado Nutricional y del VO2max en los Niveles de Adiponectina en Hombres que superan los 35 Años Influence of nutritional status and VO2max on adiponectin levels in men older than 35 years

    Directory of Open Access Journals (Sweden)

    Eduardo Camillo Martinez

    2011-06-01

    Full Text Available FUNDAMENTO: A adiponectina é considerada importante fator na patogênese das doenças cardiovasculares e metabólicas, por suas propriedades antiaterogênicas e antiinflamatórias. Poucos estudos, entretanto, sugerem a existência de relação direta entre os níveis de adiponectina e os níveis de condicionamento cardiorrespiratório e atividade física. OBJETIVO: Verificar a influência do estado nutricional e do condicionamento cardiorrespiratório nos níveis plasmáticos de adiponectina em homens adultos. MÉTODOS: Foram avaliados 250 sujeitos, homens, todos militares da ativa do Exército Brasileiro (42,6 ± 4,8 anos. Foram mensurados os níveis plasmáticos de adiponectina, massa corporal, estatura, circunferência da cintura (CC, percentual de gordura por pesagem hidrostática e VO2max por ergoespirometria. Um questionário foi utilizado para obter as características do treinamento físico realizado pelos sujeitos. RESULTADOS: Na amostra, 121 (48% sujeitos apresentaram sobrepeso e 36 (14% eram obesos. Ainda, 66 sujeitos (27% apresentaram percentual de gordura maior que 25% e 26.7% apresentaram CC > 94 cm. Sujeitos com sobrepeso e obesidade apresentaram valores significativamente menores de adiponectina em relação aqueles com estado nutricional normal. Sujeitos no mais alto tercil de VO2max apresentaram níveis de adiponectina mais altos que os demais. Os níveis de adiponectina estiveram positivamente correlacionados com o tempo total de treinamento físico semanal e com o VO2max e inversamente correlacionados com os valores de massa corporal, IMC e CC. A correlação dos níveis de adiponectina e do VO2max não permaneceu significante após controlada pelo IMC e CC. CONCLUSÃO: Sujeitos com melhor condicionamento cardiorrespiratório e com estado nutricional normal parecem apresentar níveis mais saudáveis de adiponectina.FUNDAMENTO: La adiponectina es considerada un importante factor en la patogénesis de las enfermedades

  12. Living and training in moderate hypoxia does not improve VO2 max more than living and training in normoxia.

    Science.gov (United States)

    Henderson, K K; Clancy, R L; Gonzalez, N C

    2001-06-01

    The objective of these experiments was to determine whether living and training in moderate hypoxia (MHx) confers an advantage on maximal normoxic exercise capacity compared with living and training in normoxia. Rats were acclimatized to and trained in MHx [inspired PO2 (PI(O2)) = 110 Torr] for 10 wk (HTH). Rats living in normoxia trained under normoxic conditions (NTN) at the same absolute work rate: 30 m/min on a 10 degrees incline, 1 h/day, 5 days/wk. At the end of training, rats exercised maximally in normoxia. Training increased maximal O2 consumption (VO2 max) in NTN and HTH above normoxic (NS) and hypoxic (HS) sedentary controls. However, VO2 max and O2 transport variables were not significantly different between NTN and HTH: VO2 max 86.6 +/- 1.5 vs. 86.8 +/- 1.1 ml x min(-1) x kg(-1); maximal cardiac output 456 +/- 7 vs. 443 +/- 12 ml x min(-1) x kg(-1); tissue blood O2 delivery (cardiac output x arterial O2 content) 95 +/- 2 vs. 96 +/- 2 ml x min(-1) x kg(-1); and O2 extraction ratio (arteriovenous O2 content difference/arterial O2 content) 0.91 +/- 0.01 vs. 0.90 +/- 0.01. Mean pulmonary arterial pressure (Ppa, mmHg) was significantly higher in HS vs. NS (P < 0.05) at rest (24.5 +/- 0.8 vs. 18.1 +/- 0.8) and during maximal exercise (32.0 +/- 0.9 vs. 23.8 +/- 0.6). Training in MHx significantly attenuated the degree of pulmonary hypertension, with Ppa being significantly lower at rest (19.3 +/- 0.8) and during maximal exercise (29.2 +/- 0.5) in HTH vs. HS. These data indicate that, despite maintaining equal absolute training intensity levels, acclimatization to and training in MHx does not confer significant advantages over normoxic training. On the other hand, the pulmonary hypertension associated with acclimatization to hypoxia is reduced with hypoxic exercise training.

  13. Effect of blood haemoglobin concentration on V(O2,max) and cardiovascular function in lowlanders acclimatised to 5260 m

    DEFF Research Database (Denmark)

    Calbet, J A L; Rådegran, G; Boushel, Robert Christopher

    2002-01-01

    The principal aim of this investigation was to determine the influence of blood haemoglobin concentration ([Hb]) on maximal exercise capacity and maximal O(2) consumption (V(O(2),max)) in healthy subjects acclimatised to high altitude. Secondarily, we examined the effects of [Hb] on the regulation...... of cardiac output (CO), blood pressure and muscular blood flow (LBF) during exercise. Eight Danish lowlanders (three females and five males; 24 +/- 0.6 years, mean +/- S.E.M.) performed submaximal and maximal exercise on a cycle ergometer after 9 weeks at an altitude of 5260 m (Mt Chacaltaya, Bolivia......). This was done first with the high [Hb] resulting from acclimatisation and again 2-4 days later, 1 h after isovolaemic haemodilution with Dextran 70 to near sea level [Hb]. After measurements at maximal exercise while breathing air at each [Hb], subjects were switched to hyperoxia (55 % O(2) in N(2...

  14. [Pre-operative screening tests for lung cancer using the analysis of expired gas with exercise testing--principally VO2 max/m2].

    Science.gov (United States)

    Nagamatsu, Y; Ono, H; Hiraki, H; Matsuo, T; Mitsuoka, M; Takamori, S; Hayashi, A; Yamana, H; Hayashida, R; Kakegawa, T

    1994-10-01

    The analysis of expired gas with exercise testing was conducted preoperatively with lung cancer patients in order to examine the relationship between maximum oxygen consumption (VO2 max) and postoperative complications, determining the cut-off of VO2 max/m2. The usefulness of the test as a preoperative screening test for both pulmonary ventilation and circulation was evaluated in comparison to pulmonary ventilation tests with spirometry and pulmonary circulation tests with Swan-Ganz catheter. Preoperative VO2 max/m2 was calculated from VO2 max in 111 patients with lung cancer who underwent lobectomy of more than one lobe. Also preoperatively conducted were pulmonary ventilation tests by spirometry and pulmonary circulation tests using the Swan-Ganz catheter to measure VC, %VC, FEV1.0, FEV1.0%, mean pulmonary arterial pressure (PPA) and cardiac output coefficient (C.I.). Form theses measurements, VC/m2, FEV1.0/m2 and total pulmonary vascular resistance (TPVR) were calculated. After the cut-off values of VO2 max/m2 were set tentatively at three stages, 600, 650 and 700 ml/min/m2 based on the incidence of postoperative complications, the 111 patients were divided into two groups in each cut-off value; one with VO2 max/m2 greater than the cut-off value and the other less than the cut-off value. Comparison of measurements obtained by spirometry between the two groups disclosed significant differences (p < 0.001) in VC/m2, %VC and FEV1.0/m2 in all cut-off values. Similarly, comparison of measurements obtained using the Swan-Ganz catheter between the two groups yielded significant differences (p < 0.05 to p < 0.01) in PPA and TPVR in all cut-off values.(ABSTRACT TRUNCATED AT 250 WORDS)

  15. A randomized controlled pilot study of VO2 max testing: a potential model for measuring relative in vivo efficacy of different red blood cell products.

    Science.gov (United States)

    Bennett-Guerrero, Elliott; Lockhart, Evelyn L; Bandarenko, Nicholas; Campbell, Mary L; Natoli, Michael J; Jamnik, Veronika K; Carter, Timothy R; Moon, Richard E

    2017-03-01

    Randomized trials, for example, RECESS, comparing "young" (median, 7-day) versus "middle-aged" (median, 28-day) red blood cells (RBCs), showed no difference in outcome. These data are important; however, they do not inform us about the safety and effectiveness of the oldest RBCs, which some patients receive. It may not be feasible to conduct a clinical trial randomizing patients to receive the oldest blood. Therefore, we propose strenuous exercise (VO2 max testing) as a model to study the relative efficacy to increase oxygen delivery to tissue of different RBC products, for example, extremes of storage duration. In this pilot study, eight healthy subjects had 2 units of leukoreduced RBCs collected by apheresis in AS-3 using standard methods. Subjects were randomized to receive both (2) units of their autologous RBCs at either 7 or 42 days after blood collection. VO2 max testing on a cycle ergometer was performed 2 days before (Monday) and 2 days after (Friday) the transfusion visit (Wednesday). This design avoids confounding effects on intravascular volume from the 2-unit blood transfusion. The primary outcome was the difference in VO2 max between Friday and Monday (delta VO2 max). VO2 max increased more in the 7-day RBC arm (8.7 ± 6.9% vs. 1.9 ± 6.5%, p = 0.202 for comparison between arms). Exercise duration (seconds) increased in the 7-day RBC arm (8.4 ± 1.7%) but actually decreased in the 42-day arm (-2.6 ± 3.6%, p = 0.002). This pilot study suggests that VO2 max testing has potential as a rigorous and quantitative in vivo functional assay of RBC function. Our preliminary results suggest that 42-day RBCs are inferior to 7-day RBCs at delivering oxygen to tissues. © 2016 AABB.

  16. The Effect of Training Intensity on VO2max in Young Healthy Adults: A Meta-Regression and Meta-Analysis

    OpenAIRE

    SCRIBBANS, TRISHA D.; VECSEY, STEPHAN; Hankinson, Paul B.; Foster, William S.; Brendon J Gurd

    2016-01-01

    Exercise training at a variety of intensities increases maximal oxygen uptake (VO2max), the strongest predictor of cardiovascular and all-cause mortality. The purpose of the present study was to perform a systematic review, meta-regression and meta-analysis of available literature to determine if a dose-response relationship exists between exercise intensity and training-induced increases in VO2max in young healthy adults. Twenty-eight studies involving human participants (Mean age: 23±1 yr; ...

  17. Evaluation of Maximal Oxygen Uptake (V02max) and Submaximal Estimates of VO2max Before, During and After Long Duration ISS Missions

    Science.gov (United States)

    Moore, Alan; Evetts, Simon; Feiveson, Alan; Lee, Stuart; McCleary, Frank; Platts, Steven

    2009-01-01

    NASA's Human Research Program Integrated Research Plan (HRP-47065) serves as a road-map identifying critically needed information for future space flight operations (Lunar, Martian). VO2max (often termed aerobic capacity) reflects the maximum rate at which oxygen can be taken up and utilized by the body during exercise. Lack of in-flight and immediate postflight VO2max measurements was one area identified as a concern. The risk associated with not knowing this information is: Unnecessary Operational Limitations due to Inaccurate Assessment of Cardiovascular Performance (HRP-47065).

  18. Tolerance to high-intensity intermittent running exercise: do oxygen uptake kinetics really matter?

    Directory of Open Access Journals (Sweden)

    Martin eBuchheit

    2012-10-01

    Full Text Available We examined the respective associations between aerobic fitness (VO2max, metabolic control (VO2 kinetics and locomotor function and various physiological responses to high-intensity intermittent running exercise (HIT in team sport players. Eleven players (30.5 ± 3.6 y performed a series of tests to determine their VO2max and the associated velocity (vVO2max, maximal sprinting speed (MSS and VO2 kinetics at exercise onset in the moderate and severe intensity domains, and during recovery (VO2τoff SEV. Cardiorespiratory variables, oxygenation and electromyography (EMG of lower limbs muscles and blood lactate concentration ([La] were collected during a standardized HIT protocol consisting in 8 sets of 10, 4-s runs. During HIT, four players could not complete more than 2 sets; the others finished at least 5 sets. Metabolic responses to the 2 first sets of HIT were negatively correlated with VO2max, vVO2max, and VO2τoff SEV (r=-0.6 to -0.8, while there was no clear relationship with the other variables. VO2, oxygenation and [La] responses to the first 2 sets of HIT were the only variables that differed between the players which could complete at least 5 sets or those who could not complete more than 2 sets. Players that managed to run at least 5 sets presented, in comparison with the others, greater v O2max (ES=+1.5(0.4;2.7, MSS(ES=+1.0(0.1;1.9 and training load (ES=+3.8 (2.8;4.9. There was no clear between-group difference in any of the VO2 kinetics measures (e.g., ES=-0.1(-1.4;1.2 for VO2τon SEV. While VO2max and vVO2max are likely determinant for HIT tolerance, the importance of VO2 kinetics as assessed in the present study appears limited in the present population. Knowing the main factors influencing tolerance to high-intensity intermittent running exercise may assist practitioners in personalizing training interventions.

  19. Estimativa das contribuições dos sistemas anaeróbio lático e alático durante exercícios de cargas constantes em intensidades abaixo do VO2max Estimation of contributions of the anaerobic lactic and alactic systems during constant-load exercises at intensities below the VO2max

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    Marcos David Silva-Cavalcante

    2013-01-01

    Full Text Available O objetivo do estudo foi estimar as contribuições do metabolismo anaeróbio lático (MAL e alático (MAA em intensidades abaixo do consumo máximo de oxigênio (VO2max. Dez homens (23 ± 4 anos, 176,4 ± 6,8 cm, 72,4 ± 8,2 kg, 12,0 ± 4,5 % de gordura corporal realizaram um teste progressivo até a exaustão voluntária para identificação do VO2max, da potência correspondente ao VO2max (WVO2max e do segundo limiar ventilatório (LV2. Na segunda e na terceira visita foram realizados seis testes de cargas constantes (três testes por sessão com intensidades abaixo do VO2max. Houve uma predominância do MAL sobre o MAA durante os exercícios submáximos a partir da intensidade correspondente ao LV2, sendo significativamente maior em 90% VO2max (p The purpose this study was that estimated contributions of the anaerobic lactic (MAL and alactic (MAA metabolism during constant load exercises at intensities below the maximal oxygen capacity uptake (VO2max. Ten males (23 ± 4 years, 176.4 ± 6.8 cm, 72.4 ± 8.2 kg, 12.0 ± 4.5 % of fat body performed in the first visit a progressive test until exhaustion to identification of VO2max, power output corresponding to the VO2max (WVO2max and second ventilatory threshold (LV2. On the second and third visit, the participants performed six constant workload tests (3 per session with intensities below VO2max. There was a predominance of MAL about MAA during the exercises sub-maximal from intensity corresponding to the LV2, being significantly higher at 90% VO2max (p < 0.05. Thus, these results may help coaches to implement training loads appropriate to their athletes, according to the metabolic demand of the competition.

  20. Validity of arm-leg elliptical ergometer for VO2max analysis.

    Science.gov (United States)

    Brown, Andrew B; Kueffner, Tannin E; OʼMahony, Erin C; Lockard, Michael M

    2015-06-01

    Maximal oxygen consumption ((Equation is included in full-text article.)) can be determined through multiple exercise modalities intended to elicit an individual's maximal aerobic exertion. Uphill treadmill running is considered the best modality for measuring (Equation is included in full-text article.). Previous studies have examined correlations between treadmill and elliptical ergometer tests as well as the cycle ergometer, but none of the studies use an arm-leg elliptical ergometer (ALE). The purpose of this study was to develop an ALE (Equation is included in full-text article.)testing protocol and determine whether ALE produces valid (Equation is included in full-text article.)values as compared with the treadmill. Twelve undergraduate students (mean age: 20.8 years) completed 2 (Equation is included in full-text article.)tests, 1 on a treadmill and 1 on ALE. (Equation is included in full-text article.)correlation between ALE and treadmill was examined, and paired t-tests were run for (Equation is included in full-text article.)and maximum heart rate (HRmax). A strong positive correlation was found between ALE and treadmill (Equation is included in full-text article.)values (r = 0.84; p Equation is included in full-text article.)values; however, HRmax values were higher on the treadmill than ALE (p = 0.003). Although future research is needed to examine the observed differences in HRmax between the 2 testing modalities and gender differences in muscle recruitment patterns, the results of this study suggest that ALE is a valid modality for (Equation is included in full-text article.)testing. This will be particularly valuable as a clinical tool to assess (Equation is included in full-text article.)in populations requiring low-impact exercise.

  1. Verification criteria for the determination of Vo2 MAX in the field.

    Science.gov (United States)

    Sánchez-Otero, Tania; Iglesias-Soler, Eliseo; Boullosa, Daniel A; Tuimil, José L

    2014-12-01

    The purpose of this study was to evaluate if a verification test (VT) performed in the field offers more confident results than do traditional criteria in the determination of maximal oxygen uptake ((Equation is included in full-text article.)). Twelve amateur runners (age, 36.6 ± 6.6 years) performed a maximal graded field test and after 15 minutes of passive recovery a supramaximal test to exhaustion at 105% of their velocity associated with (Equation is included in full-text article.)(v(Equation is included in full-text article.)). Traditional criteria and 2 different verification criteria were evaluated. Verification criteria were (a) maximal oxygen uptake achieved in the VT ((Equation is included in full-text article.)) must be ≤5% higher than (Equation is included in full-text article.), and (b) no significant differences of means between tests. All participants met the first verification criterion although significant differences were found between (Equation is included in full-text article.)and (Equation is included in full-text article.)(59.4 ± 5.1 vs. 56.2 ± 4.7 ml·kg·min, p max) were satisfied by 75, 66, 92, and 66 of the participants, respectively. Kappa coefficients gave a significant and substantial agreement beyond chance between traditional criteria (p max being the more stringent criteria for amateur runners. A verification protocol in the field using the criterion based on individual analysis is recommended.

  2. How to Be 80 Year Old and Have a VO2max of a 35 Year Old

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    Trine Karlsen

    2015-01-01

    Full Text Available Background. To discuss the cardiovascular and pulmonary physiology and common risk factors of an 80-year-old man with a world record maximal oxygen uptake of 50 mL·kg−1·min−1. Methods. Case report. Results. His maximal oxygen uptake of 3.31 L·min−1, maximal heart rate of 175 beats·min−1, and maximal oxygen pulse of 19 mL·beats−1 are high. He is lean (66.6 kg and muscular (49% skeletal muscle mass. His echo parameters of mitral flow (left ventricular filling, E = 82 cm·s−1 and E/A = 1.2 were normal for 40- to 60-year-old men. Systolic and diastolic function increased adequately during exercise, with no increase in left ventricular filling pressure. He has excellent pulmonary function (FVC = 4.31 L, FEV1 = 3.41, FEV1/FVC = 0.79, and DLCO = 12.0 Si1 and normal FMD and blood volumes (5.8 L. He has a high level of daily activity (10,900 steps·day−1 and 2:51 hours·day−1 of physical activity and a lifelong history of physical activity. Conclusion. The man is in excellent cardiopulmonary fitness and is highly physically active. His cardiac and pulmonary functions are above expectations for his age, and his VO2max is comparable to that of an inactive 25-year-old and of a normal, active 35-year-old Norwegian man.

  3. The Effects of 8-week Nigella sativa Supplementation and Aerobic Training on Lipid Profile and VO2 max in Sedentary Overweight Females.

    Science.gov (United States)

    Farzaneh, Esmail; Nia, Farhad Rahmani; Mehrtash, Mohammad; Mirmoeini, Fatemeh Sadat; Jalilvand, Mohammad

    2014-02-01

    Regular moderate intensity physical activity and lipid lowering effects of Nigella sativa (N. sativa) supplementation may be appropriate management for sedentary overweight females. Therefore, the aim of the present study was to examine the effects of long-term N. sativa supplementation and aerobic training on lipid profile and maximal oxygen consumption (VO2 max) in sedentary overweight females. In this randomized, double-blind, controlled trial, which was conducted in Kerman city (Iran), 20 sedentary overweight females were divided into two groups and assigned to N. sativa supplementation (N. sativa capsules) or a placebo for the 8 weeks, both groups participated in an aerobic training program (3 times/week). Each N. sativa capsule contained 500 ± 10 mg N. sativa crushed seeds and subjects had to take 2 g N. sativa per day for 8 weeks. Blood lipids and VO2 max were determined at baseline and at the end of 8 weeks. N. sativa supplementation lowered total cholesterol (TC) (P high density lipoprotein (HDL) and VO2 max (P training program lowered TC (P training program and N. sativa supplementation lowered LDL and HDL (P training plus N. sativa supplementation have a synergistic effect in improve profile lipid parameters.

  4. Seasonal variations in VO2max, O2-cost, O2-deficit, and performance in elite cross-country skiers.

    Science.gov (United States)

    Losnegard, Thomas; Myklebust, Håvard; Spencer, Matt; Hallén, Jostein

    2013-07-01

    Long-term effects of training are important information for athletes, coaches, and scientists when associating changes in physiological indices with changes in performance. Therefore, this study monitored changes in aerobic and anaerobic capacities and performance in a group of elite cross-country skiers during a full sport season. Thirteen men (age, 23 ± 2 years; height, 182 ± 6 cm; body mass, 76 ± 8 kg; V2 roller ski skating VO2max, 79.3 ± 4.4 ml·kg·min or 6.0 ± 0.5 L·min) were tested during the early, middle, and late preparation phase: June (T1), August (T2), and October (T3); during the competition phase: January/February (T4); and after early precompetition phase: June (T5). O2-cost during submaximal efforts, V[Combining Dot Above]O2peak, accumulated oxygen deficit (ΣO2-deficit), and performance during a 1,000-m test were determined in the V2 ski skating technique on a roller ski treadmill. Subjects performed their training on an individual basis, and detailed training logs were categorized into different intensity zones and exercise modes. Total training volume was highest during the summer months (early preseason) and decreased toward and through the winter season, whereas the volume of high-intensity training increased (all p testing sessions for 1,000 m time, O2-cost, and ΣO2-deficit (Cohen's d effect size; ES = 0.63-1.37, moderate to large, all p < 0.05). In general, the changes occurred between T1 and T3 with minor changes in the competitive season (T3 to T4). No significant changes were found in V[Combining Dot Above]O2peak across the year (ES = 0.17, trivial). In conclusion, the training performed by elite cross-country skiers induced no significant changes in V[Combining Dot Above]O2peak but improved performance, O2-cost, and ΣO2-deficit.

  5. CONSUMO MÁXIMO DE OXÍGENO (VO2max EN BOMBEROS: REVISIÓN SISTEMÁTICA DE ESTUDIOS

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    Jimmy Rojas Quirós

    2013-07-01

    Full Text Available Rojas, J.(2012.Maximun oxygen consumption (VO2max in fire fighters: a systematic review of studies. The fireman's profession is listed as a profession of risk, with high physical requirement;, in recent years the firefighter has acquired more powers itself out fires,including interventions in traffic accidents, hazardous materials incidents, rescues, forest fires, among others. The traditional image of the firefighter has given way to new professionals ready to face all kinds of disasters by the talk today offullfirefighter. The aimof this studywas to systematically reviewthe scientific evidence onthe level ofmaximun oxygen intake(VO2max that a firefightermust haveto fulfill theirdaily obligations. Weincludeda total of 19studies, publishedbetween 2002and2012, fromEBSCOhostdatabases, SpringerLink, SPORTDiscusandjournalsas Journalof SportsScience&Medicine, among others. We concludethisreview, based on the resultsof the studies, that different populationsoffire, haunt aVO2maxof34.80 to 58.21ml/kg/min, which varieswiththe initial conditionfirefightersstudies proposingdifferentauthors, in generalit is determined thata firefightermust haveVO2maxvaluesabove43 ml/kg/min, which is the minimumrecommended toat leasthave a goodaerobic capacitythat enablesfunction inits core functionsas a firefighter.ResumenConsumo máximo de oxígeno (VO2max en bomberos: revisión sistemática de estudios. El trabajo de bombero es catalogada como una profesión de riesgo, con alto requerimiento físico; en los últimos años el bombero ha adquirido más competencias que la propia de apagar incendios, entre ellas las intervenciones en accidentes de tránsito, incidentes con materiales peligrosos, rescates, fuegos forestales, entre otros. La imagen del bombero tradicional ha dado paso a nuevos profesionales preparados para afrontar todo tipo de desastres por lo que se habla en la actualidad del bombero completo. El objetivo de este estudio fue revisar sistemáticamente la

  6. Sport-specific fitness testing differentiates professional from amateur soccer players where VO2max and VO2 kinetics do not.

    Science.gov (United States)

    Wells, C M; Edwards, A M; Winter, E M; Fysh, M L; Drust, B

    2012-06-01

    The purpose of this study was to identify if sport-specific and cardiopulmonary exercise testing differentiated professional from amateur soccer players. Thirty six men comprising 18 professional (mean±s: age 23.2±2.4 years) and 18 amateur (mean±SD: age 21.1±1.6 years) soccer players participated and performed four tests on separate occasions: 1) a graded exercise test to determine VO2max; 2) four exercise transients from walking to 80%Δ for the determination of VO2 kinetics; 3) the Yo-Yo Intermittent Recovery Test level 2 (Yo-Yo IR2) and 4) a repeated sprint test (RST). The players did not differ in VO2max (professional 56.5±2.9 mL.kg-1.min-1; amateur 55.7±3.5 mL.kg-1.min-1: P=0.484) or VO2 kinetic fundamental measures (τ1 onset, professional 24.5±3.2 s; amateur 24.0±1.8 s: τ1 cessation, professional 28.7±2.8 s; amateur 29.3±3.5 s: P=0.923). However, the amateurs were outperformed in the Yo-Yo IR2 (Professional 966±153 m; Amateur 840±156 m) (P=0.034) and RST (best time, professional 6.46±0.27 s; amateur 6.84±0.24 s, P=0.012). Performance indices derived from field-based sport-specific performance tests identified significant differences between professional and amateur players (Ptests of VO2 kinetics nor VO2max differentiated between groups, suggesting laboratory tests of cardiorespiratory parameters are probably less consequential to soccer than sport-specific field-based observations.

  7. Determinación del Vo2max en un grupo de adultos que practican natación recreativa en la ciudad de Tres Arroyos

    OpenAIRE

    2015-01-01

    El presente trabajo se encuadra dentro de la realidad de un grupo de personas que practican Natación de forma recreativa en la ciudad de Tres Arroyos. El tema que rige la investigación de la tesis se basa en la determinación del Consumo máximo de oxígeno (Vo2 max) de los nadadores a través de pruebas indirectas1, test máximo incremental de Lavoie realizadas en la piscina. Además se tomaron otros test en donde las variables fueron tiempo y distancia a máxima intensidad, estos fu...

  8. Influência do estado nutricional e do VO2max nos níveis de adiponectina em homens acima de 35 anos

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    Eduardo Camillo Martinez

    2011-06-01

    Full Text Available FUNDAMENTO: A adiponectina é considerada importante fator na patogênese das doenças cardiovasculares e metabólicas, por suas propriedades antiaterogênicas e antiinflamatórias. Poucos estudos, entretanto, sugerem a existência de relação direta entre os níveis de adiponectina e os níveis de condicionamento cardiorrespiratório e atividade física. OBJETIVO: Verificar a influência do estado nutricional e do condicionamento cardiorrespiratório nos níveis plasmáticos de adiponectina em homens adultos. MÉTODOS: Foram avaliados 250 sujeitos, homens, todos militares da ativa do Exército Brasileiro (42,6 ± 4,8 anos. Foram mensurados os níveis plasmáticos de adiponectina, massa corporal, estatura, circunferência da cintura (CC, percentual de gordura por pesagem hidrostática e VO2max por ergoespirometria. Um questionário foi utilizado para obter as características do treinamento físico realizado pelos sujeitos. RESULTADOS: Na amostra, 121 (48% sujeitos apresentaram sobrepeso e 36 (14% eram obesos. Ainda, 66 sujeitos (27% apresentaram percentual de gordura maior que 25% e 26.7% apresentaram CC > 94 cm. Sujeitos com sobrepeso e obesidade apresentaram valores significativamente menores de adiponectina em relação aqueles com estado nutricional normal. Sujeitos no mais alto tercil de VO2max apresentaram níveis de adiponectina mais altos que os demais. Os níveis de adiponectina estiveram positivamente correlacionados com o tempo total de treinamento físico semanal e com o VO2max e inversamente correlacionados com os valores de massa corporal, IMC e CC. A correlação dos níveis de adiponectina e do VO2max não permaneceu significante após controlada pelo IMC e CC. CONCLUSÃO: Sujeitos com melhor condicionamento cardiorrespiratório e com estado nutricional normal parecem apresentar níveis mais saudáveis de adiponectina.

  9. Supervised physical exercise improves VO2max, quality of life, and health in early stage breast cancer patients: a randomized controlled trial.

    Science.gov (United States)

    Casla, Soraya; López-Tarruella, Sara; Jerez, Yolanda; Marquez-Rodas, Iván; Galvão, Daniel A; Newton, Robert U; Cubedo, Ricardo; Calvo, Isabel; Sampedro, Javier; Barakat, Rubén; Martín, Miguel

    2015-09-01

    Breast cancer patients suffer impairment in cardiorespiratory fitness after treatment for primary disease, affecting patients' health and survival. The aim of this study was to evaluate the ability of a pragmatic exercise intervention to improve cardiorespiratory fitness of breast cancer patients after primary treatment. Between February 2013 and December 2014, 94 women with early stage (I-III) breast cancer, 1-36 months post-chemotherapy, and radiotherapy were randomly assigned to an intervention program (EX) combining supervised aerobic and resistance exercise (n = 44) or usual care (CON) (n = 45) for 12 weeks. Primary study endpoint was VO2max. Secondary endpoints were muscle strength, shoulder range of motion, body composition, and quality of life (QoL). Assessments were undertaken at baseline, 12-week, and 6-month follow-ups. Eighty-nine patients aged 29-69 years were assessed at baseline and 12 weeks. The EX group showed significant improvements in VO2max, muscle strength, percent fat, and lean mass (p ≤ 0.001 in all cases) and QoL compared with usual care (CON). Apart from body composition, improvements were maintained for the EX at 6-month follow-up. There were no adverse events during the testing or exercise intervention program. A combined exercise intervention produced considerable improvement in cardiorespiratory fitness, physical function, and quality of life in breast cancer patients previously treated with chemotherapy and radiation therapy. Importantly, most of these benefits were maintained 6 months after ceasing the supervised exercise intervention.

  10. Study of the relationship between the aerobic capacity (VO2 max) and the rating of perceived exertion based on the measurement of heart beat in the metal industries Esfahan

    Science.gov (United States)

    Habibi, Ehsanollah; Dehghan, Habibollah; Moghiseh, Mohammad; Hasanzadeh, Akbar

    2014-01-01

    Background and Objective: To establish a balance between work (physical exercise) and human beings, the aerobic capacity (VO2 max) could be used as a measure. Additionally, the subjective and physiological assessment could be applied as one of the methods for assessing physical exercise. The most commonly used tools for the assessment of fatigue during physical exercise include the Borg scale Rating of perceived Exertion (RPE) in relation to subjective symptoms and heart rate (HR) in relation to physiological symptoms. The study is aimed to investigate the relationship between the aerobic capacity and the RPE based on the measurement of heat rate (HR) of workers from the Metal Industries of Isfahan. Materials and Methods: The subjects were 200 male workers from metal components manufacturers in Isfahan selected by using random sampling based on statistic method. The subjects were examined by using ergometer in accordance with A strand 6 minutes cycle test protocol. Furthermore, the subjects were asked to rate their status based on the Borg rating scale at the end of each minute. Additionally, their heat rates were monitored and recorded automatically at the end of each minutes. Results: Statistical analysis showed that there was a significant relationship between the RPE and the aerobic capacity (VO2 max) (r = –0.904, P VO2 max (r = 0.991, P VO2 max and HR. Conclusions: The results indicated that there was a strong relationship between the RPE and VO2 max, as well as a greater correlation between HR and VO2 max. Therefore, the HR could be used as a Prediction measure to estimate VO2 max. PMID:25077148

  11. The effects of modified exponential tapering technique on perceived exertion, heart rate, time trial performance, VO2max and power output among highly trained junior cyclists.

    Science.gov (United States)

    Ishak, Asmadi; Hashim, Hairul A; Krasilshchikov, Oleksandr

    2016-09-01

    The present study investigated the effects of a 2-week modified exponential taper on physiological adaptation and time trial performance among junior cyclists. Participants (N.=27) with the mean age of 16.95±0.8 years, height of 165.6±6.1 cm and weight of 54.19±8.1 kg were matched into either modified exponential taper (N.=7), normal exponential taper (N.=7), or control (N.=7) groups using their initial VO2max values. Both experimental groups followed a 12-week progressive endurance training program and subsequently, a 2-week tapering phase. A simulated 20-km time trial performance along with VO2max, power output, heart rate and rating of perceived exertion were measured at baseline, pre and post-taper. One way ANOVA was used to analyze the difference between groups before the start of the intervention while mixed factorial ANOVA was used to analyze the difference between groups across measurement sessions. When homogeneity assumption was violated, the Greenhouse-Geisser Value was used for the corrected values of the degrees of freedom for the within subject factor the analysis. Significant interactions between experimental groups and testing sessions were found in VO2max (F=6.67, df=4, P<0.05), power output (F=5.02, df=4, P<0.05), heart rate (F=10.87, df=2.51, P<0.05) rating of perceived exertion (F=13.04, df=4, P<0.05) and 20KM time trial (F=4.64, df=2.63, P<0.05). Post-hoc analysis revealed that both types of taper exhibited positive effects compared to the non-taper condition in the measured performance markers at post-taper while no different were found between the two taper groups. It was concluded that both taper protocols successfully inducing physiological adaptations among the junior cyclists by reducing the volume and maintaining the intensity of training.

  12. The contribution of preintervention blood pressure, VO2max, BMI, autonomic function and gender to exercise-induced changes in heart rate variability.

    Science.gov (United States)

    Grant, Catharina C; Janse van Rensburg, Dina C

    2013-06-01

    The quantification of heart rate variability (HRV) is a tool to assess the interaction between exercise and autonomic control, as well as the pathophysiology of diseases affecting autonomic function. Little is known about the influence of genetically influenced physiology on exercise-induced changes in autonomic cardiac regulation. It was theorised that preintervention values for blood pressure, VO2max, body mass index (BMI), autonomic function and gender contribute significantly to the exercise-induced changes in HRV. A 12-week, medium-to-high intensity exercise intervention was completed by 183 volunteers (18-22 years). Data were sampled at baseline and after 12 weeks. Standard time domain, frequency domain and Poincaré HRV quantification techniques were implemented. Regression analysis was performed to determine the influences of the predictors (baseline values for low frequency  (LF), high frequency (HF), BMI, VO2max, gender, blood pressure) on the exercise-induced response of the dependent variables (changes in HRV-indicator values). Parameters found to be significant (pexercise-induced changes were LF, HF and systolic blood pressure in, respectively, 10, 5 and 2 of the 12 regressions performed. The results indicated that the independent variables contribute between 12.83% and 29.82%, depending on the specific HRV indicator, to the exercise-induced changes in the autonomic nervous system. Preintervention autonomic status, as represented specifically by LF, is the most important determinant of cardiac autonomic response to an exercise intervention in a healthy study population. Baseline autonomic function could thus be a significant confounder in the outcome of exercise study results.

  13. A acurácia da determinação do VO2max e do limiar anaeróbio La exactitud en la determinacion del VO2máx y del umbral anaerobico Accuracy of VO2max and anaerobic threshold determination

    Directory of Open Access Journals (Sweden)

    Paulo Cesar N Granja Filho

    2005-06-01

    Full Text Available São raros estudos que tratam da acurácia de parâmetros de trocas gasosas durante o esforço, com a população brasileira. OBJETIVO: Determinar a confiabilidade do consumo máximo de oxigênio (VO2max e do limiar anaeróbio (LAn, assim como, a objetividade do segundo (LAn em adultos jovens saudáveis. MÉTODOS: Foram aplicados dois testes de esforço máximo, a partir dos quais dois observadores independentes determinaram o LAn através do método de inspeção visual. Os dados foram tratados por meio da análise de regressão, coeficiente de correlação intraclasse (CCI, ANOVA com dois fatores com teste post hoc de Tukey e teste t pareado para alfa Son raros los estudios que tratan de la exactitud de los parámetros de cambios gaseosos durante el esfuerzo con la población brasileña. OBJETIVO: Determinar la confiabilidad del consumo máximo de oxigeno (VO2max y del umbral anaeróbico (LAn, así como la objetividad del segundo, (LAn en adultos jovenes saludables. MÉTODOS: Fueron aplicados dos tests de esfuerzo máximo, a partir de los cuales dos observadores independientes determinaron el LAn a través del método de inspección visual. Los datos fueron tratados por medio del análisis de regresión, coeficiente de relación intraclase (CCI, ANOVA com dos factores con test post hoc de Tukey y el test t apareado para alfa Studies on the accuracy of the gas exchange and ventilation parameters during exertion involving the Brazilian population are scarce in literature. OBEJCTIVE: To determine the reliability of the maximal oxygen intake (VO2max and anaerobic threshold (AnT, as well as the objectivity of the AnT determination in Brazilian healthy youth adults. METHODS: Two tests of maximal exertion were applied. Two independent observers applied the visual inspection method for the AnT determination. The data were compared by means of the regression analysis, intraclass correlation coefficient (ICC, two-way ANOVA and the paired t-test for an

  14. Vmax estimate from three-parameter critical velocity models: validity and impact on 800 m running performance prediction.

    Science.gov (United States)

    Bosquet, Laurent; Duchene, Antoine; Lecot, François; Dupont, Grégory; Leger, Luc

    2006-05-01

    The purpose of this study was to evaluate the validity of maximal velocity (Vmax) estimated from three-parameter systems models, and to compare the predictive value of two- and three-parameter models for the 800 m. Seventeen trained male subjects (VO2max=66.54+/-7.29 ml min(-1) kg(-1)) performed five randomly ordered constant velocity tests (CVT), a maximal velocity test (mean velocity over the last 10 m portion of a 40 m sprint) and a 800 m time trial (V 800 m). Five systems models (two three-parameter and three two-parameter) were used to compute V max (three-parameter models), critical velocity (CV), anaerobic running capacity (ARC) and V800m from times to exhaustion during CVT. Vmax estimates were significantly lower than (0.19Critical velocity (CV) alone explained 40-62% of the variance in V800m. Combining CV with other parameters of each model to produce a calculated V800m resulted in a clear improvement of this relationship (0.83

  15. 补服乳清蛋白对人体最大吸氧量的影响%Effects of supplementation Whey-protein On VO2max

    Institute of Scientific and Technical Information of China (English)

    任秀红; 张翔; 杨多多

    2012-01-01

    This study examined the effects of whey-protein, or placebo on VO2max, researched effects of intaking whey protein on aerobic exercise power as well. Method: twelve healthy males who major in PE participated in this research study. Single-blind design was employed, participants performed three times increasing the load continuous on anaerobic power cycling which lasted for 3 minutes followed by consumption of 7g whey-protein, 14g whey-protein or placebo 30 minutes before exercise. Results: There was significantly different between supplementation 7g whey-protein and placebo(p〈.05), similarly there was very significantly different between intaklng 7g whey-protein and 14g whey-protein(p〈.01).Conclusion: supplementation different mount of whey-protein has different effects on VO2max, Maybe supplementation whey-protein will effect the power of aerobic exercise.%目的:研究补服不同量的乳清蛋白对人体最大吸氧量的变化,探讨补服乳清蛋白对人体有氧运动能力的影响。方法:采用单盲实验法,体育系12名健康男性大学生作为被试,每次(共3次)补服不同的补剂,然后在无氧功率自行车上进行3个连续三分钟的递增负荷运动,作自身对照。结果:补服7g和14g乳清蛋白与安慰剂相比最大吸氧量水平都有不同程度的变化,补服7g乳清蛋白与安慰剂相比差异性显著,p〈0.05,补服14g乳清蛋白与安慰剂相比差异性非常显著p〈0.01。结论:(1)补服不同量的乳清蛋白都不同程度影响人体的最大吸氧量水平;(2)说明乳清蛋白的补服对人体有氧运动能力有一定影响。

  16. Middle cerebral artery blood velocity during running

    DEFF Research Database (Denmark)

    Lyngeraa, Tobias; Pedersen, Lars Møller; Mantoni, T

    2013-01-01

    for eight subjects, respectively, were excluded from analysis because of insufficient signal quality. Running increased mean arterial pressure and mean MCA velocity and induced rhythmic oscillations in BP and in MCA velocity corresponding to the difference between step rate and heart rate (HR) frequencies......) blood flow velocity, photoplethysmographic finger BP, and step frequency were measured continuously during three consecutive 5-min intervals of treadmill running at increasing running intensities. Data were analysed in the time and frequency domains. BP data for seven subjects and MCA velocity data....... During running, rhythmic oscillations in arterial BP induced by interference between HR and step frequency impact on cerebral blood velocity. For the exercise as a whole, average MCA velocity becomes elevated. These results suggest that running not only induces an increase in regional cerebral blood flow...

  17. Indices of training stress during competitive running and swimming seasons.

    Science.gov (United States)

    Flynn, M G; Pizza, F X; Boone, J B; Andres, F F; Michaud, T A; Rodriguez-Zayas, J R

    1994-01-01

    Eight male cross-country runners and five male swimmers were tested four times during their collegiate seasons. Each trial corresponded to a different training load. The runners' trials were conducted before the start of organized practice (RT1), after 3 wk of increased training (RT2), 3 wk prior to the conference championship (pre-taper, RT3), and 4 d after the conference championship (post-taper, RT4). The swimmers' trials were conducted after the first 9 wk of training (ST1), after completing 2 wk of hard training (ST2), after an additional 6 wk of training (pre-taper, ST3) and during a week following the conference championship (post-taper, ST4). Venous blood samples, heart rate (HR) and blood pressure (BP) were obtained after 15 min supine rest (0700 h). Serum was analyzed for cortisol (C), total testosterone (TT), free testosterone (FT), and creatine kinase (CK). Blood samples (lactate), HR and RPE were obtained during a fixed velocity run (75% preseason VO2max) and blood samples and RPE following a 365.8 m swim (90% preseason VO2max). The runners then completed a "performance run" to exhaustion (110% preseason VO2max) and the swimmers completed maximal 22.9 and 365.8 m swims. Serum CK, C, TT, FT, and the TT:C and FT:C ratios were not significantly different among trials for the runners. Serum TT and FT were significantly (P swimmers at ST2 (TT 16.7 +/- 2.5; FT 85.3 +/- 8.5) compared to ST1 (TT 30.3 +/- 2.8; FT 130.2 +/- 20.9) whereas, C, TT:C or FT:C were not significantly altered.(ABSTRACT TRUNCATED AT 250 WORDS)

  18. 初中生台阶试验、800米跑与 VO2 max 的相关性研究%Relevant Studies on Step Tests for Junior Middle SChool Students., Long-distance Race of 800 Meters and VO2 max

    Institute of Scientific and Technical Information of China (English)

    彭丽英

    2014-01-01

    The study tests the aerobic capabilities of junior middle school students by means of literature statistics , experiment and mathematical statistics , aimming at studying the appropriate way of testing the aerobic capabilities of junior middle school students, which provides data supports for further testing the physique qualities of middle school students .The research findings suggest that the relevance of step tests for junior middle school students and the relative value of VO 2 max are respectively as r =0. 12,r=0.08, P>0.05;The relevance between Long -distance race of 800 meters and VO2 max is repectively as r=-0.19,r=-0.20, p>0.05.The two testing ways has little relations with VO 2 max.The research findings suggest that there are some defi-ciencies on testing the aerobic capabilities of junior middle school students by means of step tests and Long -distance race of 800 meters which couldn ’ t efficiently reflect cardiovascular functions of middle school students .It is inapproriate to test the aerobic endurance capabilities in high school graduation exams by means of this method .%采用文献资料法、实验法、数理统计法对初中生有氧运动能力进行测试,其目的是研究适合测试初中生有氧运动能力的方法。为今后中学生体质测试方法的完善提供数据支撑。其研究结果:初中男、女生台阶试验与最大摄氧量( VO2 max)相对值的相关性分别为r=0.12,r=0.08,p值均大于0.05;800米跑与VO2 max相对值的相关性分别为r=-0.19,r=-0.20,p值均大于0.05。两种方法均与VO2 max呈微弱关系。结果表明:台阶试验、800米跑用于评定初中生有氧耐力存在一定的问题,此两种方法不能有效的反映中学生的心血管机能水平。中考中利用此方法来评定有氧耐力水平欠妥当。

  19. Middle cerebral artery blood velocity during running.

    Science.gov (United States)

    Lyngeraa, T S; Pedersen, L M; Mantoni, T; Belhage, B; Rasmussen, L S; van Lieshout, J J; Pott, F C

    2013-02-01

    Running induces characteristic fluctuations in blood pressure (BP) of unknown consequence for organ blood flow. We hypothesized that running-induced BP oscillations are transferred to the cerebral vasculature. In 15 healthy volunteers, transcranial Doppler-determined middle cerebral artery (MCA) blood flow velocity, photoplethysmographic finger BP, and step frequency were measured continuously during three consecutive 5-min intervals of treadmill running at increasing running intensities. Data were analysed in the time and frequency domains. BP data for seven subjects and MCA velocity data for eight subjects, respectively, were excluded from analysis because of insufficient signal quality. Running increased mean arterial pressure and mean MCA velocity and induced rhythmic oscillations in BP and in MCA velocity corresponding to the difference between step rate and heart rate (HR) frequencies. During running, rhythmic oscillations in arterial BP induced by interference between HR and step frequency impact on cerebral blood velocity. For the exercise as a whole, average MCA velocity becomes elevated. These results suggest that running not only induces an increase in regional cerebral blood flow but also challenges cerebral autoregulation. © 2012 John Wiley & Sons A/S.

  20. Effects of running velocity on running kinetics and kinematics.

    Science.gov (United States)

    Brughelli, Matt; Cronin, John; Chaouachi, Anis

    2011-04-01

    Sixteen semiprofessional Australian football players performed running bouts at incremental velocities of 40, 60, 80, and 100% of their maximum velocity on a Woodway nonmotorized force treadmill. As running velocity increased from 40 to 60%, peak vertical and peak horizontal forces increased by 14.3% (effect size [ES] = 1.0) and 34.4% (ES = 4.2), respectively. The changes in peak vertical and peak horizontal forces from 60 to 80% were 1.0% (ES = 0.05) and 21.0% (ES = 2.9), respectively. Finally, the changes in peak vertical and peak horizontal forces from 80% to maximum were 2.0% (ES = 0.1) and 24.3% (ES = 3.4). In addition, both stride frequency and stride length significantly increased with each incremental velocity (p velocity (p velocity (r = 0.47). For the kinematic variables, only stride length was found to have a significant positive correlation with maximum running velocity (r = 0.66). It would seem that increasing maximal sprint velocity may be more dependent on horizontal force production as opposed to vertical force production.

  1. The Effects of a Duathlon Simulation on Ventilatory Threshold and Running Economy

    Directory of Open Access Journals (Sweden)

    Nathaniel T. Berry, Laurie Wideman, Edgar W. Shields, Claudio L. Battaglini

    2016-06-01

    Full Text Available Multisport events continue to grow in popularity among recreational, amateur, and professional athletes around the world. This study aimed to determine the compounding effects of the initial run and cycling legs of an International Triathlon Union (ITU Duathlon simulation on maximal oxygen uptake (VO2max, ventilatory threshold (VT and running economy (RE within a thermoneutral, laboratory controlled setting. Seven highly trained multisport athletes completed three trials; Trial-1 consisted of a speed only VO2max treadmill protocol (SOVO2max to determine VO2max, VT, and RE during a single-bout run; Trial-2 consisted of a 10 km run at 98% of VT followed by an incremental VO2max test on the cycle ergometer; Trial-3 consisted of a 10 km run and 30 km cycling bout at 98% of VT followed by a speed only treadmill test to determine the compounding effects of the initial legs of a duathlon on VO2max, VT, and RE. A repeated measures ANOVA was performed to determine differences between variables across trials. No difference in VO2max, VT (%VO2max, maximal HR, or maximal RPE was observed across trials. Oxygen consumption at VT was significantly lower during Trial-3 compared to Trial-1 (p = 0.01. This decrease was coupled with a significant reduction in running speed at VT (p = 0.015. A significant interaction between trial and running speed indicate that RE was significantly altered during Trial-3 compared to Trial-1 (p < 0.001. The first two legs of a laboratory based duathlon simulation negatively impact VT and RE. Our findings may provide a useful method to evaluate multisport athletes since a single-bout incremental treadmill test fails to reveal important alterations in physiological thresholds.

  2. The effects of incline and level-grade high-intensity interval treadmill training on running economy and muscle power in well-trained distance runners.

    Science.gov (United States)

    Ferley, Derek D; Osborn, Roy W; Vukovich, Matthew D

    2014-05-01

    Despite a paucity of evidence, uphill running has been touted as a sport-specific resistance-to-movement training tactic capable of enhancing metabolic, muscular, and neuromuscular processes in distance runners in ways similar to previously established resistance-to-movement training methods, such as heavy and/or explosive strength training and plyometric training. Therefore, the purpose of this investigation included documenting the effects of incline and level-grade interval treadmill training on indices of running economy (RE) (i.e., oxygen consumption [VO2] and blood lactate [BLa] responses of submaximal running) and muscle power. Thirty-two well-trained distance runners (age, 27.4 ± 3.8 years; body mass, 64.8 ± 8.9 kg; height, 173.6 ± 6.4 cm; and VO2max, 60.9 ± 8.5 ml·min(-1)·kg(-1)) received assignment to an uphill (GHill = 12), level-grade (GFlat = 12), or control (GCon = 8) group. GHill and GFlat completed 12 interval and 12 continuous run sessions over 6 weeks, whereas GCon maintained their normal training. Dependent variables measured before and after training were VO2 and BLa at 2 separate velocities associated with lactate threshold (VLT) (VO2-60% and VO2-80%; and BLa-60% and BLa-80%, respectively); percentage of VO2max at lactate threshold (%VO2max at VLT); muscle power as assessed through a horizontal 5-jump test (5Jmax); and isokinetic knee extension and flexion at 3 angular velocities (90, 180, and 300°·s(-1)). Statistical significance was set to p ≤ 0.05. All groups significantly improved 5Jmax, VO2-60%, VO2-80%, BLa-60%, and BLa-80%. Additionally, GHill and GFlat significantly improved %VO2max at VLT. Other indices of RE and muscle power did not improve. We conclude incline treadmill training effective for improving the components of RE, but insufficient as a resistance-to-movement exercise for enhancing muscle power output.

  3. Oxygen cost of running barefoot vs. running shod.

    Science.gov (United States)

    Hanson, N J; Berg, K; Deka, P; Meendering, J R; Ryan, C

    2011-06-01

    The purpose of this study was to investigate the oxygen cost of running barefoot vs. running shod on the treadmill as well as overground. 10 healthy recreational runners, 5 male and 5 female, whose mean age was 23.8±3.39 volunteered to participate in the study. Subjects participated in 4 experimental conditions: 1) barefoot on treadmill, 2) shod on treadmill, 3) barefoot overground, and 4) shod overground. For each condition, subjects ran for 6 min at 70% vVO (2)max pace while VO (2), heart rate (HR), and rating of perceived exertion (RPE) were assessed. A 2 × 2 (shoe condition x surface) repeated measures ANOVA revealed that running with shoes showed significantly higher VO (2) values on both the treadmill and the overground track (pbarefoot. It was concluded that at 70% of vVO (2)max pace, barefoot running is more economical than running shod, both overground and on a treadmill.

  4. Comparative analysis of the 1-mile run test evaluation formulae: Assessment of aerobic capacity in male law enforcement officers aged 20–23 years

    Directory of Open Access Journals (Sweden)

    Gürhan Kayihan

    2014-04-01

    Full Text Available Objectives: The purpose of this study was to compare values of aerobic performance in the 1-mile run test (1-MRT using different formulae. Material and Methods: Aerobic capacities of 351 male volunteers working for the Turkish National Police within the age range of 20-23 years were evaluated by the 1-MRT and the 20-metre shuttle run (20-MST. VO2max values were estimated by the prediction equations developed by George et al. (1993, Cureton et al. (1995 and Kline et al. (1987 for the 1-MRT and by Leger and Lambert (1982 for the 20-MST. Results: The difference between the results of the different formulae was significant (p = 0.000. The correlation coefficient between the estimated VO2max using Cureton's equation, George's equation, Kline's equation and the 20-MST were 0.691 (p < 0.001, 0.486 (p < 0.001 and 0.608 (p < 0.001, respectively. The highest correlation coefficient was between the VO2max estimated by the 20-MST and Cureton's equation. Similarly, the highest correlation coefficient (r = -0.779 was between the 1-mile run time and the VO2max estimated by Cureton's equation. Conclusions: When analysing more vigorous exercise than sub-maximal exercise, we suggest that Cureton's equation be used to predict the VO2max from 1-mile run/walk performance in large numbers of healthy individuals with high VO2max. This research compares the use of 3 different formulae to estimate VO2max from 1-mile run/ walk performance in male law enforcement officers aged 20-23 years for the first time and reports the most accurate formula to use when evaluating aerobic capacities of large numbers of healthy individuals.

  5. A PILOT STUDY COMPARING TWO FIELD TESTS WITH THE TREADMILL RUN TEST IN SOCCER PLAYERS

    Directory of Open Access Journals (Sweden)

    Abdul Rashid Aziz

    2005-06-01

    Full Text Available This study compares the performances obtained during soccer-specific field tests of the 20 m multistage shuttle run test (MST and the Yo-Yo intermittent endurance test (YIET, with the measured maximal oxygen uptake (VO2max obtained in both field tests as well as that obtained in the traditional test of running to exhaustion on a treadmill (TRT, in young trained soccer players. Twenty-one National-level youth players performed, in random order, the MST and YIET to determine the relationship between the two field tests. From these, eight randomly chosen players performed their field tests as well as a TRT, equipped with an ambulatory gas exchange measurement device. Pearson correlation coefficient analysis showed that the players' performance (i.e. distance covered in the MST and YIET was correlated (r = 0.65, p 0.05. In contrast, significant correlations were observed between the players' performance in the MST with the measured VO2max obtained in the same MST and in the YIET (both p < 0.05; and attained almost statistical significance with the measured VO2max in the TRT (p = 0.06. The lack of association between distances covered in the YIET with all the measured VO2max values suggest that measured VO2max per se may not be suitable to characterize soccer players' intermittent endurance performance. In comparison with the MST, the YIET may be a more favourable field-based assessment of soccer player's endurance performance

  6. Comparison of the 1.5 Mile Run Times at 7,200 Feet and Simulated 850 Feet in a Hyperoxic Room

    Science.gov (United States)

    2012-03-01

    review and Maximum oxygen uptake treadmill ( VO2 max ) test introduction 30 min – VO2 max ...Maximal Oxygen Update ( VO2 max ) Test ......................................... 7 Figure 3 - VO2 Max results for Male, Female and All Subjects. * p...0.001 between Male and Female VO2 ’s. ............................................................. 11 Figure 4 - VO2 Max vs Predicted VO2 Max at

  7. Running on a lower-body positive pressure treadmill

    DEFF Research Database (Denmark)

    Raffalt, Peter C; Hovgaard-Hansen, Line; Jensen, Bente Rona

    2013-01-01

    This study investigated maximal oxygen consumption (VO2max) and time to exhaustion while running on a lower-body positive pressure treadmill (LBPPT) at normal body weight (BW) as well as how BW support affects respiratory responses, ground reaction forces, and stride characteristics....

  8. In healthy elderly postmenopausal women variations in BMD and BMC at various skeletal sites are associated with differences in weight and lean body mass rather than by variations in habitual physical activity, strength or VO2max.

    Science.gov (United States)

    Schöffl, I; Kemmler, W; Kladny, B; Vonstengel, S; Kalender, W A; Engelke, K

    2008-01-01

    The objective of this study was an integrated cross-sectional investigation for answering the question whether differences in bone mineral density in elderly postmenopausal women are associated with differences in habitual physical activity and unspecific exercise levels. Two hundred and ninety nine elderly women (69-/+3 years), without diseases or medication affecting bone metabolism were investigated. The influence of weight, body composition and physical activity on BMD was measured at multiple sites using different techniques (DXA, QCT, and QUS). Physical activity and exercise level were assessed by questionnaire, maximum strength of the legs and aerobic capacity. Variations in physical activity or habitual exercise had no effect on bone. The only significant univariate relation between strength/VO(2)max and BMD/BMC that remained after adjusting for confounding variables was between arm BMD (DXA) and hand-grip strength. The most important variable for explaining BMD was weight and for cortical BMC of the femur (QCT) lean body mass. Weight and lean body mass emerge as predominant predictors of BMD in normal elderly women, whereas the isolated effect of habitual physical activity, unspecific exercise participation, and muscle strength on bone parameters is negligible. Thus, an increase in the amount of habitual physical activity will probably have no beneficial impact on bone.

  9. The relationship between the interval shuttle run test and maximal oxygen uptake in soccer players

    NARCIS (Netherlands)

    Lemmink, KAPM; Visscher, C

    2003-01-01

    The aim of this study was to determine the relationship between the interval shuttle run test (ISRT) and maximal oxygen uptake (VO2max) in soccer players. The ISRT was developed to measure interval endurance capacity. During the ISRT, subjects alternately run for 30 sec and walk for 15 sec with

  10. Estimating Heart Rate, Energy Expenditure, and Physical Performance With a Wrist Photoplethysmographic Device During Running.

    Science.gov (United States)

    Parak, Jakub; Uuskoski, Maria; Machek, Jan; Korhonen, Ilkka

    2017-07-25

    Wearable sensors enable long-term monitoring of health and wellbeing indicators. An objective evaluation of sensors' accuracy is important, especially for their use in health care. The aim of this study was to use a wrist-worn optical heart rate (OHR) device to estimate heart rate (HR), energy expenditure (EE), and maximal oxygen intake capacity (VO2Max) during running and to evaluate the accuracy of the estimated parameters (HR, EE, and VO2Max) against golden reference methods. A total of 24 healthy volunteers, of whom 11 were female, with a mean age of 36.2 years (SD 8.2 years) participated in a submaximal self-paced outdoor running test and maximal voluntary exercise test in a sports laboratory. OHR was monitored with a PulseOn wrist-worn photoplethysmographic device and the running speed with a phone GPS sensor. A physiological model based on HR, running speed, and personal characteristics (age, gender, weight, and height) was used to estimate EE during the maximal voluntary exercise test and VO2Max during the submaximal outdoor running test. ECG-based HR and respiratory gas analysis based estimates were used as golden references. OHR was able to measure HR during running with a 1.9% mean absolute percentage error (MAPE). VO2Max estimated during the submaximal outdoor running test was closely similar to the sports laboratory estimate (MAPE 5.2%). The energy expenditure estimate (n=23) was quite accurate when HR was above the aerobic threshold (MAPE 6.7%), but MAPE increased to 16.5% during a lighter intensity of exercise. The results suggest that wrist-worn OHR may accurately estimate HR during running up to maximal HR. When combined with physiological modeling, wrist-worn OHR may be used for an estimation of EE, especially during higher intensity running, and VO2Max, even during submaximal self-paced outdoor recreational running.

  11. Estimating Heart Rate, Energy Expenditure, and Physical Performance With a Wrist Photoplethysmographic Device During Running

    Science.gov (United States)

    Uuskoski, Maria; Machek, Jan; Korhonen, Ilkka

    2017-01-01

    Background Wearable sensors enable long-term monitoring of health and wellbeing indicators. An objective evaluation of sensors’ accuracy is important, especially for their use in health care. Objective The aim of this study was to use a wrist-worn optical heart rate (OHR) device to estimate heart rate (HR), energy expenditure (EE), and maximal oxygen intake capacity (VO2Max) during running and to evaluate the accuracy of the estimated parameters (HR, EE, and VO2Max) against golden reference methods. Methods A total of 24 healthy volunteers, of whom 11 were female, with a mean age of 36.2 years (SD 8.2 years) participated in a submaximal self-paced outdoor running test and maximal voluntary exercise test in a sports laboratory. OHR was monitored with a PulseOn wrist-worn photoplethysmographic device and the running speed with a phone GPS sensor. A physiological model based on HR, running speed, and personal characteristics (age, gender, weight, and height) was used to estimate EE during the maximal voluntary exercise test and VO2Max during the submaximal outdoor running test. ECG-based HR and respiratory gas analysis based estimates were used as golden references. Results OHR was able to measure HR during running with a 1.9% mean absolute percentage error (MAPE). VO2Max estimated during the submaximal outdoor running test was closely similar to the sports laboratory estimate (MAPE 5.2%). The energy expenditure estimate (n=23) was quite accurate when HR was above the aerobic threshold (MAPE 6.7%), but MAPE increased to 16.5% during a lighter intensity of exercise. Conclusions The results suggest that wrist-worn OHR may accurately estimate HR during running up to maximal HR. When combined with physiological modeling, wrist-worn OHR may be used for an estimation of EE, especially during higher intensity running, and VO2Max, even during submaximal self-paced outdoor recreational running. PMID:28743682

  12. The determination of critical rest interval from the intermittent critical velocity test in club-level collegiate hockey and rugby players.

    Science.gov (United States)

    Fukuda, David H; Smith, Abbie E; Kendall, Kristina L; Cramer, Joel T; Stout, Jeffrey R

    2011-04-01

    The intermittent critical velocity (ICV) test is used to quantify the relationship between velocity and time to exhaustion, yielding an aerobic parameter (ICV), an anaerobic parameter (anaerobic running capacity [ARC]), and critical rest interval (CRI). Critical rest interval is the theoretical rest period needed to maintain repeated bouts of exercise for an extended period of time without inducing fatigue during intermittent treadmill running. Fourteen collegiate, club-level male participants (mean ± SD; age: 21.4 ± 1.8 years; weight: 82.8 ± 5.9 kg; body fat: 11.8 ± 5.4%; and VO2max: 51.2 ± 2.8 ml · kg · min), primarily hockey and rugby players, completed the ICV test, using 15-second repeated sprints to exhaustion during separate sessions of treadmill running at varying supramaximal intensities. The time and total distance for each running session were used to determine ICV and ARC via linear regression. The CRI was calculated using the relationship between total distance during the ICV test and the number of intervals completed. Mean ICV and ARC (± SD) values were calculated as 4.80 ± 0.3 m · s and 154.1 ± 36 m, respectively. The mean ICV values were significantly different from the mean peak velocity (± SD) (4.67 ± 0.17 m · s) achieved during the VO2max test (p = 0.011). The CRI was calculated as mean ± SD: 33.9 ± 1.9 seconds. Body fat percentage measured by air displacement plethysmography (BOD POD®; r = -0.649; p = 0.012), lean body mass (r = -0.556; p = 0.039), fat mass (r = -0.634; p = 0.015), body weight (r = -0.669; p = 0.006), and relative VO2max (r = 0.562; p = 0.036) were significantly correlated with ICV. The ARC (r = 0.804; p = 0.001) and velocity at ventilatory threshold (r = -0.630; p = 0.016) were significantly correlated with CRI. The ability to quantify CRI, an additional variable derived from the ICV test, provides a possible measure that can be used in the prescription and evaluation of training methods.

  13. Factors affecting running economy in trained distance runners.

    Science.gov (United States)

    Saunders, Philo U; Pyne, David B; Telford, Richard D; Hawley, John A

    2004-01-01

    Running economy (RE) is typically defined as the energy demand for a given velocity of submaximal running, and is determined by measuring the steady-state consumption of oxygen (VO2) and the respiratory exchange ratio. Taking body mass (BM) into consideration, runners with good RE use less energy and therefore less oxygen than runners with poor RE at the same velocity. There is a strong association between RE and distance running performance, with RE being a better predictor of performance than maximal oxygen uptake (VO2max) in elite runners who have a similar VO2max). RE is traditionally measured by running on a treadmill in standard laboratory conditions, and, although this is not the same as overground running, it gives a good indication of how economical a runner is and how RE changes over time. In order to determine whether changes in RE are real or not, careful standardisation of footwear, time of test and nutritional status are required to limit typical error of measurement. Under controlled conditions, RE is a stable test capable of detecting relatively small changes elicited by training or other interventions. When tracking RE between or within groups it is important to account for BM. As VO2 during submaximal exercise does not, in general, increase linearly with BM, reporting RE with respect to the 0.75 power of BM has been recommended. A number of physiological and biomechanical factors appear to influence RE in highly trained or elite runners. These include metabolic adaptations within the muscle such as increased mitochondria and oxidative enzymes, the ability of the muscles to store and release elastic energy by increasing the stiffness of the muscles, and more efficient mechanics leading to less energy wasted on braking forces and excessive vertical oscillation. Interventions to improve RE are constantly sought after by athletes, coaches and sport scientists. Two interventions that have received recent widespread attention are strength training and

  14. The energetics of ultra-endurance running.

    Science.gov (United States)

    Lazzer, Stefano; Salvadego, Desy; Rejc, Enrico; Buglione, Antonio; Antonutto, Guglielmo; di Prampero, Pietro Enrico

    2012-05-01

    Our objective was to determine the effects of long-lasting endurance events on the energy cost of running (C(r)), and the role of maximal oxygen uptake (VO(2max)), its fractional utilisation (F) and C(r) in determining the performance. Ten healthy runners (age range 26-59 years) participated in an ultra-endurance competition consisting of three running laps of 22, 48 and 20 km on three consecutive days in the North-East of Italy. Anthropometric characteristics and VO(2max) by a graded exercise test on a treadmill were determined 5 days before and 5 days after the competition. In addition, C(r) was determined on a treadmill before and after each running lap. Heart rate (HR) was recorded throughout the three laps. Results revealed that mean C(r) of the individual laps did not increase significantly with lap number (P = 0.200), thus ruling out any chronic lap effect. Even so, however, at the end of lap 3, C(r) was 18.0% (P increase of C(r-mean) during the competition yields to marked worsening of the performance, and (2) the three variables F, VO(2max) and C(r-mean) combined as described above explaining 87% of the total competition time variance.

  15. Physiological responses at five estimates of critical velocity.

    Science.gov (United States)

    Bull, Anthony J; Housh, Terry J; Johnson, Glen O; Rana, Sharon R

    2008-04-01

    The purpose of this study was to compare critical velocity (CV) estimates from five mathematical models, and to examine the oxygen uptake (VO(2)) and heart rate (HR) responses during treadmill runs at the five estimates of CV. Ten subjects (six males and four females) performed one incremental test to determine maximal oxygen consumption (VO(2max)) and four or five randomly ordered constant-velocity trials on a treadmill for the estimation of CV. Five mathematical models were used to estimate CV for each subject including two linear, two nonlinear, and an exponential model. Up to five randomly ordered runs to exhaustion were performed by each subject at treadmill velocities that corresponded to the five CV estimates, and VO(2) and HR responses were monitored throughout each trial. The 3-parameter, nonlinear (Non-3) model produced CV estimates that were significantly (P < 0.05) less than the other four models. During runs at CV estimates, five subjects did not complete 60 min at the their estimate from the Non-3 model, nine did not complete 60 min at their estimate from the Non-2 model, and no subjects completed 60 min at any estimate from the other three models. The mean HR value (179 +/- 18 beats min(-1), HR(peak)) at the end of runs at CV using the Non-3 model was significantly less than the maximal HR (195 +/- 7 beats min(-1), HR(max)) achieved during the incremental trial to exhaustion. However, mean HR(peak) values from runs at all other CV estimates were not significantly different from HR(max). Furthermore, data indicated that mean HR(peak) values increased during runs at CV estimates from the third minute to the end of exercise for all models, and that these increases in VO(2) (range = 367-458 ml min(-1)) were significantly greater than that typically associated with O(2) drift ( approximately 200 ml min(-1)) for all but the exponential model, indicating a VO(2) slow component associated with CV estimates from four of the five models. However, the mean VO(2

  16. Muscle fibre conduction velocity and cardiorespiratory response during incremental cycling exercise in young and older individuals with different training status.

    Science.gov (United States)

    Lenti, M; De Vito, G; Sbriccoli, P; Scotto di Palumbo, A; Sacchetti, M

    2010-08-01

    We investigated the effect of ageing and training on muscle fibre conduction velocity (MFCV) and cardiorespiratory response during incremental cycling exercise. Eight young (YT; 24+/-5 yrs) and eight older (OT; 64+/-3 yrs) cyclists, together with eight young (YU; 27+/-4 yrs) and eight older (OU; 63+/-2 yrs) untrained individuals underwent to an incremental maximal test on a cycle ergometer. Ventilatory threshold (VT), respiratory compensation point (RCP) and maximal oxygen uptake (VO(2)max) were identified and MFCV recorded from the vastus lateralis muscle using surface electromyography with linear arrays electrodes. In YT MFCV increased with the exercise intensity, reaching a peak of 4.99+/-1.02 [m/s] at VT. Thereafter, and up to VO(2)max, MFCV declined. In YU MFCV showed a similar trend although the peak [4.55+/-0.53m/s] was observed, at 75% of VO(2)max an intensity higher than VT (66% of VO(2)max). In both YT and YU MFCV did not decline until RPC, which occurred at 78% VO(2)max in YU and at 92% VO(2)max (P<0.01) in YT. Differently from young individuals, MFCV in older subjects did not increase with exercise intensity. Moreover, maximal MFCV in OU was significantly lower [3.53+/-0.40 m/s;] than that of YT (P<0.005) and YU (P<0.05). The present study shows that, especially in young individuals, MFCV reflects cardiorespiratory response during incremental dynamic cyclic exercise and hence can be used to investigate motor unit recruitment strategies.

  17. Maximal and submaximal physiological responses to adaptation to deep water running.

    Science.gov (United States)

    Azevedo, Liane B; Lambert, Mike I; Zogaib, Paulo S; Barros Neto, Turibio L

    2010-02-01

    The aim of the study was to compare physiological responses between runners adapted and not adapted to deep water running at maximal intensity and the intensity equivalent to the ventilatory threshold. Seventeen runners, either adapted (n = 10) or not adapted (n = 7) to deep water running, participated in the study. Participants in both groups undertook a maximal treadmill running and deep water running graded exercise test in which cardiorespiratory variables were measured. Interactions between adaptation (adapted vs. non-adapted) and condition (treadmill running vs. deep water running) were analysed. The main effects of adaptation and condition were also analysed in isolation. Runners adapted to deep water running experienced less of a reduction in maximum oxygen consumption (VO2max) in deep water running compared with treadmill running than runners not adapted to deep water running. Maximal oxygen consumption, maximal heart rate, maximal ventilation, VO2max at the ventilatory threshold, heart rate at the ventilatory threshold, and ventilation at the ventilatory threshold were significantly higher during treadmill than deep water running. Therefore, we conclude that adaptation to deep water running reduces the difference in VO2max between the two modalities, possibly due to an increase in muscle recruitment. The results of this study support previous findings of a lower maximal and submaximal physiological response on deep water running for most of the measured parameters.

  18. The critical velocity in swimming.

    Science.gov (United States)

    di Prampero, Pietro E; Dekerle, Jeanne; Capelli, Carlo; Zamparo, Paola

    2008-01-01

    In supra-maximal exercise to exhaustion, the critical velocity (cv) is conventionally calculated from the slope of the distance (d) versus time (t) relationship: d = I + St. I is assumed to be the distance covered at the expense of the anaerobic capacity, S the speed maintained on the basis of the subject's maximal O(2) uptake (VO2max) This approach is based on two assumptions: (1) the energy cost of locomotion per unit distance (C) is constant and (2) VO2max is attained at the onset of exercise. Here we show that cv and the anaerobic distance (d (anaer)) can be calculated also in swimming, where C increases with the velocity, provided that VO2max its on-response, and the C versus v relationship are known. d (anaer) and cv were calculated from published data on maximal swims for the four strokes over 45.7, 91.4 and 182.9 m, on 20 elite male swimmers (18.9 +/- 0.9 years, 75.9 +/- 6.4 kg), whose VO2max and C versus speed relationship were determined, and compared to I and S obtained from the conventional approach. cv was lower than S (4, 16, 7 and 11% in butterfly, backstroke, breaststroke and front crawl) and I (=11.6 m on average in the four strokes) was lower than d (anaer). The latter increased with the distance: average, for all strokes: 38.1, 60.6 and 81.3 m over 45.7, 91.4 and 182.9 m. It is concluded that the d versus t relationship should be utilised with some caution when evaluating performance in swimmers.

  19. Predicting intermittent running performance: critical velocity versus endurance index.

    Science.gov (United States)

    Buchheit, M; Laursen, P B; Millet, G P; Pactat, F; Ahmaidi, S

    2008-04-01

    The aim of the present study was to examine the ability of the critical velocity (CV) and the endurance index (EI) to assess endurance performance during intermittent exercise. Thirteen subjects performed two intermittent runs: 15-s runs intersected with 15 s of passive recovery (15/15) and 30-s runs with 30-s rest (30/30). Runs were performed until exhaustion at three intensities (100, 95 and 90 % of the speed reached at the end of the 30 - 15 intermittent fitness test, V (IFT)) to calculate i) CV from the slope of the linear relationship between the total covered distance and exhaustion time (ET) (iCV); ii) anaerobic distance capacity from the Y-intercept of the distance/duration relationship (iADC); and iii) EI from the relationship between the fraction of V (IFT) at which the runs were performed and the log-transformed ET (iEI). Anaerobic capacity was indirectly assessed by the final velocity achieved during the Maximal Anaerobic Running Test (VMART). ET was longer for 15/15 than for 30/30 runs at similar intensities. iCV (15/15) and iCV (30/30) were not influenced by changes in ET and were highly dependent on V (IFT). Neither iADC (15/15) nor iADC (30/30) were related to VMART. In contrast, iEI (15/15) was higher than iEI (30/30), and corresponded with the higher ET. In conclusion, only iEI estimated endurance capacity during repeated intermittent running.

  20. Running economy assessment within cardiopulmonary exercise testing for recreational runners.

    Science.gov (United States)

    Engeroff, Tobias; Bernardi, Andreas; Vogt, Lutz; Banzer, Winfried

    2016-03-01

    The aim of this study was to evaluate the influence of running economy (RE) on running performance within recreational runners of different maximal aerobic capacity, and the feasibility of RE assessment within routine cardiopulmonary exercise testing (CPET). Sixty-eight recreational runners (m: 49, f: 19; age: 21-54) completed a graded exercise test (GXT) until exhaustion. Maximal oxygen uptake and respiratory compensation point were obtained via CPET. RE was calculated as relative oxygen uptake per covered distance (mL/kg/km) one step below respiratory compensation point (RCP). Subjects were grouped for RE via median split and categorized into one of six fitness levels (Very Poor, Poor, Fair, Good, Excellent, Superior) (ACSM 2010). Irrespective of fitness levels, recreational runners with a more energy efficient movement (REVO2max values ranged between 35.2 and 66.0 ml/min/kg. Running velocity at RCP of runners within VO2max categories Good and Superior differed significantly (P<0.05) between RE groups. This study provides evidence that RE influences submaximal running performance in recreational distance runners within a broad range of maximal aerobic capacity. Complementing routine CPET with RE assessment at physiological threshold intensities and ACSM based categorization seems feasible to delineate the impact of movement efficiency and aerobic fitness on performance in recreational runners.

  1. Short-term changes in 10-km race pace aerobic demand and gait mechanics following a bout of high-intensity distance running.

    Science.gov (United States)

    Morgan, D W; Strohmeyer, H S; Daniels, J T; Beaudoin, C C; Craib, M W; Borden, R A; Greer, P J; Burleson, C L

    1996-01-01

    Following treadmill accommodation and a 3-day period of tapered running, ten well-trained male distance runners [x maximum oxygen uptake (VO2max) = 71.3 ml.kg-1.min-1] performed two 10-min level treadmill runs designed to assess running economy at 90% VO2max. Video recordings were obtained during the last minute of each run to quantify selected gait descriptors. Two to 3 days following the second economy run, each subject completed 30 min of high-intensity (HI) running at 90% VO2max. One 2, and 4 days after the HI run, subjects repeated the 10-min economy runs. Compared to pre HI-run values, no significant change (P > 0.05) in running economy was observed during the post-HI runs. Biomechanical analyses also revealed that running style remained unaltered after the HI run. These results support earlier findings obtained on moderately trained subjects featuring measurement of running economy and gait mechanics at less-demanding intensities and suggest that among well-trained athletes, 30 min of HI running does not elicit an increase in VO2 or disrupt gait mechanics over the short term in subsequent distance runs performed at near-maximal speeds.

  2. Pairwise velocities in the "Running FLRW" cosmological model

    Science.gov (United States)

    Bibiano, Antonio; Croton, Darren J.

    2017-01-01

    We present an analysis of the pairwise velocity statistics from a suite of cosmological N-body simulations describing the "Running Friedmann-Lemaître-Robertson-Walker" (R-FLRW) cosmological model. This model is based on quantum field theory in a curved space-time and extends ΛCDM with a time-evolving vacuum energy density, ρ _Λ. To enforce local conservation of matter a time-evolving gravitational coupling is also included. Our results constitute the first study of velocities in the R-FLRW cosmology, and we also compare with other dark energy simulations suites, repeating the same analysis. We find a strong degeneracy between the pairwise velocity and σ8 at z = 0 for almost all scenarios considered, which remains even when we look back to epochs as early as z = 2. We also investigate various Coupled Dark Energy models, some of which show minimal degeneracy, and reveal interesting deviations from ΛCDM which could be readily exploited by future cosmological observations to test and further constrain our understanding of dark energy.

  3. Cadetes of the Academia do Polícia Militar do Estado do Rio de Janeiro Correlación entre VO2 max, gordura relativa y perfil lipídico, en cadetes de la Academia de Policía Militar del Estado de Río de Janeiro

    Directory of Open Access Journals (Sweden)

    E. H. M. Dantas

    2010-09-01

    Full Text Available The objective of the present study was to verify the correlation level among the max, the relative fat and the profile lipídico of 51 Cadets (Age = 23.63 3.58 years; Weight = 74.13 ± 10.46 kg; Height = 1.76 ± 0.06 m; IMC = 23.99 2.76 kg/m2, of the masculine gender, of the Academy of the Military police of the State of Rio de Janeiro, of the year of 2007. The subjects were active and participants of the military physical training (TFM accomplished five times a week, with duration of 60 minutes for session. They were appraised: the max for ergoespirometria (I record of progressive effort, with constant inclination of 3% and initial speed of 4,0km/h, the relative fat (% G - I record of three cutaneous folds and the profile lipídico, through the method Enzymatic Calorimétrico in the variables: total cholesterol (CT, triglicérides (TG, lipoproteína of density high-cholesterol (HDL-C and lipoproteína of density low-cholesterol (LDL-C. The test of correlation of Spearman presented correlation significant between max and TG (r = -0,289; p = 0,04,  max and HDL-C (r = 0,277; p = 0,049,% G and TG (r = 0,296; p = 0,035,% G and HDL-C (r = 0,338; p = 0,015. Like this, these discoveries point a discreet relationship between the profile lipídico and the maximum consumption of oxygen corroborating the need to consider other factors as the feeding and the intensity of the exercises in the investigation of this relationship.

    Key Words: training,  VO2 max, relative fat, lipidic profile.

     

    El objetivo del presente estudio es establecer el nivel de correlación entre el  VO2 max, la grasa relativa y el perfil lipídico de 51 cadetes varones (Edad = 23.63 ± 3.58 años; Peso = 74.13 ± 10.46 Kg.; Talla = 1.76  ± 0.06 m; IMC = 23.99 ± 2.76 Kg. /m2 de la Academia de la Policía Militar del Estado de Río de Janeiro, del año de 2007. Los sujetos son f

  4. Effects of downhill or uphill training prior to a downhill run.

    Science.gov (United States)

    Pierrynowski, M R; Tüdus, P M; Plyley, M J

    1987-01-01

    Nine men volunteered to undergo 10% downhill (DT) or 10% uphill (UT) treadmill training at 60% VO2max for 12 minutes on two consecutive days. Four days later the downhill run (DR) was repeated. All subjects reported considerable muscular soreness following DT but not UT. When DR followed UT muscular soreness was again reported but not when DR followed DT. Peak knee flexion and extension moment of force data at five angular velocities, ranging from 0.52-4.71 rad s-1, were reduced following DR regardless of whether soreness was present. During each run VO2 was stable during UT but drifted upwards during DT and DR. This increase in VO2 was not due to changes in the stride frequency since the stride frequency remained nearly constant on all days except for the second day of the DT when an increase of 20 strides per minute occurred; this was the only day the subjects ran while sore. It was concluded that two 12 minute bouts of downhill running were sufficient to protect against the occurrence of muscular soreness in subsequent downhill run. However, this training was insufficient to prevent a 2-3 day loss of muscular strength. These results support the hypothesis that the sensation of delayed onset muscle soreness and the temporary strength loss associated with eccentric contraction have different physiological causes.

  5. The Effects of Backwards Running Training on Forward Running Economy in Trained Males.

    Science.gov (United States)

    Ordway, Jason D; Laubach, Lloyd L; Vanderburgh, Paul M; Jackson, Kurt J

    2016-03-01

    Backwards running (BR) results in greater cardiopulmonary response and muscle activity compared with forward running (FR). BR has traditionally been used in rehabilitation for disorders such as stroke and lower leg extremity injuries, as well as in short bursts during various athletic events. The aim of this study was to measure the effects of sustained backwards running training on forward running economy in trained male athletes. Eight highly trained, male runners (26.13 ± 6.11 years, 174.7 ± 6.4 cm, 68.4 ± 9.24 kg, 8.61 ± 3.21% body fat, 71.40 ± 7.31 ml·kg(-1)·min(-1)) trained with BR while harnessed on a treadmill at 161 m·min(-1) for 5 weeks following a 5-week BR run-in period at a lower speed (134 m·min(-1)). Subjects were tested at baseline, postfamiliarized, and post-BR training for body composition, a ramped VO2max test, and an economy test designed for trained male runners. Subjects improved forward running economy by 2.54% (1.19 ± 1.26 ml·kg(-1)·min(-1), p = 0.032) at 215 m·min(-1). VO2max, body mass, lean mass, fat mass, and % body fat did not change (p > 0.05). Five weeks of BR training improved FR economy in healthy, trained male runners without altering VO2max or body composition. The improvements observed in this study could be a beneficial form of training to an already economical population to improve running economy.

  6. Optimizing strength training for running and cycling endurance performance: A review.

    Science.gov (United States)

    Rønnestad, B R; Mujika, I

    2014-08-01

    Here we report on the effect of combining endurance training with heavy or explosive strength training on endurance performance in endurance-trained runners and cyclists. Running economy is improved by performing combined endurance training with either heavy or explosive strength training. However, heavy strength training is recommended for improving cycling economy. Equivocal findings exist regarding the effects on power output or velocity at the lactate threshold. Concurrent endurance and heavy strength training can increase running speed and power output at VO2max (Vmax and Wmax, respectively) or time to exhaustion at Vmax and Wmax. Combining endurance training with either explosive or heavy strength training can improve running performance, while there is most compelling evidence of an additive effect on cycling performance when heavy strength training is used. It is suggested that the improved endurance performance may relate to delayed activation of less efficient type II fibers, improved neuromuscular efficiency, conversion of fast-twitch type IIX fibers into more fatigue-resistant type IIA fibers, or improved musculo-tendinous stiffness.

  7. Better economy in field running than on the treadmill: evidence from high-level distance runners

    Directory of Open Access Journals (Sweden)

    M Mooses

    2015-05-01

    Full Text Available Given the ongoing interest in ways to improve the specificity of testing elite athletes in their natural environment, portable metabolic systems provide an opportunity to assess metabolic demand of exercise in sport-specific settings. Running economy (RE and maximal oxygen uptake ( ·VO 2 max were compared between track and treadmill (1% inclination conditions in competitive level European distance runners who were fully habituated to treadmill running (n = 13. All runners performed an exercise test on running track and on treadmill. While ·VO 2 max was similar on the track and on the treadmill (68.5 ± 5.3 vs. 71.4 ± 6.4 ml∙kg -1 ∙min -1 , p = 0.105, respectively, superior RE was found on the track compared to the treadmill (215.4 ± 12.4 vs. 236.8 ± 18.0 O2 ml∙kg -1 ∙km -1 , p < 0.001. RE on the track was strongly correlated with RE on the treadmill (r = 0.719, p = 0.006. The present findings indicate that high-level distance runners have significantly better RE but not ·VO2max on the track compared to treadmill. This difference may be due to biomechanical adjustments. As RE is strongly correlated between the two conditions, it would be reasonable to assume that interventions affecting RE on the treadmill will also affect RE on the track.

  8. Relação da potência aeróbica máxima e da força muscular com a economia de corrida em atletas de endurance Relación de la potencia aeróbica máxima y de la fuerza muscular con la economía de le carrera en atletas de endurance Relationship of maximal aerobic power and muscular strength with the running economy in endurance athletes

    Directory of Open Access Journals (Sweden)

    Luiz Guilherme Antonacci Guglielmo

    2005-02-01

    and the intensity corresponding to the VO2max (IVO2max; b constant-velocity treadmill run to determine RE; c 1-RM test in the leg press and; d maximal vertical jump test (VJ. VO2max (63.8 ± 8.3 ml/kg/min was significantly correlated (r = 0.63; p < 0.05 with RE (48.0 ± 6.6 ml/kg/min. However, the IVO2max (18.7 ± 1.1 km/h, the maximal isotonic strength (230.3 ± 41.2 kg and the VJ (30.8 ± 3.8 cm were not significantly correlated with RE. One concludes that the maximal aerobic power can explain in part the inter-individual RE variability in endurance athletes. However, maximal isotonic strength and explosive strength seem not to be associated with RE values observed in this group of athletes.

  9. The Comparison of Two Incremental Exercise Test Models of Ramp and GXT in Direct Measurement of VO2max%Ramp与GXT两种递增负荷模式在VO2max直接测试中的比较研究

    Institute of Scientific and Technical Information of China (English)

    胡国鹏; 王振; 刘无逸; 冯魏; 孟妍

    2016-01-01

    比较连续斜坡式递增负荷模式(Ramp)和连续分级递增负荷模式(graded exercise text,GXT)在最大摄氧量直接测试中的生理变量变化特征.方法:对20名体力活动良好的男性受试者分剐进行3次不同负荷模式的极量力竭测试,3种负荷模式分别为GXT、Ramp和105%最大负荷持续运动(constant exercise test,105 %CT).结果:Ramp与GXT测试结果相比,两测试中最大摄氧量(VO2 max、VO2max/kg)高度相关(r=0.726~0.882,P<0.01)且无显著性差异(P<0.01);而最高功率(Wmax)、血乳酸(La)均表现为Ramp测试值低于GXT测试值;两测试时长(T)高度相关且Ramp测试值较短;Ramp测试中VO2 max、VO2 max/kg、最高心率(HRmax)、呼吸商(RER)和105%CT测试中值无显著性差别.GXT、Ramp两测试中,根据平台定义不同所达到平台的百分比不同.结论:在同样的平均递增负荷幅度下,两负荷方案对不同峰值参数存在不同影响;Ramp可作为直接测试最大摄氧量替代方案,并且所达到的峰值功率及时间较低、较短;依照最大摄氧量不同平台判定标准,平台出现概率受测试方案及判定标准影响较大,ACSM推荐的平台标准不适用于Ramp测试.

  10. Research on the Correlation between the .VO2 max and Resting Function of Heart and Lung-Taking Female College Students in Non-Sports Professional as an Example%最大耗氧量与安静时心输出量和肺呼吸功能相关性研究--以非运动专业的青年女大学生为例

    Institute of Scientific and Technical Information of China (English)

    程宙明; 卢健; 牛俊茹; 张涛; 陈贝贝; 邱林利; 陈彩珍; 季浏

    2015-01-01

    Objective :This paper explores the correlation between .VO2 max and function of rest‐ing heart and lung ,and compare the difference in participants of different .VO2 max level be‐tween .VO2 max and function of heart and lung .Method :Testing 66 female college students’ (age :20 ± 6 ,BMI :20 .88 ± 1 .32 ) .VO2 max ,Cardiac output ,and lung function .Dividing the participants into two groups (normal or less than normal) based on the testing results .Con‐ducting Independent‐Samples T Test on each groups .Results :1) There is a significant correla‐tion between .VO2max(ml/kg/min) with VE (P 0 .05);3)The ventila‐tion volume of the“below‐average” group is significantly lower than the“normal” group while the respiration quotient of the former group is larger than the latter one’ s ( P 0 .05);5)The MET ,QLD and EVP of the participants in the“below‐average” group ,to some extent ,fluctuate with small range and lack amplitude .Conclusions :1) .VO2 max is greatly influenced by the ventilation volume and is posi‐tively correlated with the lungs breathing vibration intensity .However ,it is uncorrelated with the cardiac output in a static situation ;2) The depth of respiration of the “normal” group (in sports) is significantly higher than the“below‐average” group ,which is possibly due to a bet‐ter oxygen utilization in metabolism and energy supply ;3) Participants with different .VO2 max levels show no significant difference of heart function in a static situation ,suggesting that par‐ticipants of the“below‐average” group didn't lose on the "starting line" ;4) Participants of the“below‐average” group lacks advantage in terms of the overall Aerobic capacity ,which + also seems to affect their cardiopulmonary function when doing sports .%目的:探讨最大耗氧量(.VO2 max )与安静时心脏、肺功能的相关性,以及不同.VO2 max水平受试者的心脏和肺功能差异。方法:对66

  11. Velocity changes, long runs, and reversals in the Chromatium minus swimming response.

    OpenAIRE

    Mitchell, J G; Martinez-Alonso, M.; Lalucat, J.; Esteve, I; Brown, S.

    1991-01-01

    The velocity, run time, path curvature, and reorientation angle of Chromatium minus were measured as a function of light intensity, temperature, viscosity, osmotic pressure, and hydrogen sulfide concentration. C. minus changed both velocity and run time. Velocity decreased with increasing light intensity in sulfide-depleted cultures and increased in sulfide-replete cultures. The addition of sulfide to cultures grown at low light intensity (10 microeinsteins m-2 s-1) caused mean run times to i...

  12. POSTURAL CONTROL AFTER A PROLONGED TREADMILL RUN AT INDIVIDUAL VENTILATORY AND ANAEROBIC THRESHOLD

    Directory of Open Access Journals (Sweden)

    Laura Guidetti

    2011-09-01

    Full Text Available The objective of the study was to verify whether young males' balance was affected by 30min prolonged treadmill running (TR at individual ventilatory (IVT and anaerobic (IAT thresholds in recovery time. The VO2max, IAT and IVT during an incremental TR were determined. Mean displacement amplitude (Acp and velocity (Vcp of center of pressure were recorded before (pre and after (0min post; 5min post; and 10min post prolonged TR at IAT and IVT, through posturographic trials performed with eyes open (EO and closed (EC. Significant differences between IVT and IAT for Vcp, between EO and EC for Acp and Vcp, were observed. The IAT induced higher destabilizing effect when postural trials were performed with EC. The IVT intensity produced also a destabilizing effect on postural control immediately after exercise. An impairment of postural control after prolonged treadmill running exercise at IVT and IAT intensity was showed. However, destabilizing effect on postural control disappeared within 10min after IAT intensity and within 5min after IVT intensity

  13. Improved running economy and increased hemoglobin mass in elite runners after extended moderate altitude exposure.

    Science.gov (United States)

    Saunders, P U; Telford, R D; Pyne, D B; Hahn, A G; Gore, C J

    2009-01-01

    There is conflicting evidence whether hypoxia improves running economy (RE), maximal O(2) uptake (V(O)(2max)), haemoglobin mass (Hb(mass)) and performance, and what total accumulated dose is necessary for effective adaptation. The aim of this study was to determine the effect of an extended hypoxic exposure on these physiological and performance measures. Nine elite middle distance runners were randomly assigned to a live high-train low simulated altitude group (ALT) and spent 46+/-8 nights (mean+/-S.D.) at 2860+/-41m. A matched control group (CON, n=9) lived and trained near sea level ( approximately 600m). ALT decreased submaximal V(O)(2) (Lmin(-1)) (-3.2%, 90% confidence intervals, -1.0% to -5.2%, p=0.02), increased Hb(mass) (4.9%, 2.3-7.6%, p=0.01), decreased submaximal heart rate (-3.1%, -1.8% to -4.4%, p=0.00) and had a trivial increase in V(O)(2max) (1.5%, -1.6 to 4.8; p=0.41) compared with CON. There was a trivial correlation between change in Hb(mass) and change in V(O)(2max) (r=0.04, p=0.93). Hypoxic exposure of approximately 400h was sufficient to improve Hb(mass), a response not observed with shorter exposures. Although total O(2) carrying capacity was improved, the mechanism(s) to explain the lack of proportionate increase in V(O)(2max) were not identified.

  14. Physical Activity Enhances Metabolic Fitness Independently of Cardiorespiratory Fitness in Marathon Runners

    Science.gov (United States)

    Laye, M. J.; Nielsen, M. B.; Hansen, L. S.; Knudsen, T.; Pedersen, B. K.

    2015-01-01

    High levels of cardiovascular fitness (CRF) and physical activity (PA) are associated with decreased mortality and risk to develop metabolic diseases. The independent contributions of CRF and PA to metabolic disease risk factors are unknown. We tested the hypothesis that runners who run consistently >50 km/wk and/or >2 marathons/yr for the last 5 years have superior metabolic fitness compared to matched sedentary subjects (CRF, age, gender, and BMI). Case-control recruitment of 31 pairs of runner-sedentary subjects identified 10 matched pairs with similar VO2max (mL/min/kg) (similar-VO2max). The similar-VO2max group was compared with a group of age, gender, and BMI matched pairs who had the largest difference in VO2max (different-VO2max). Primary outcomes that defined metabolic fitness including insulin response to an oral glucose tolerance test, fasting lipids, and fasting insulin were superior in runners versus sedentary controls despite similar VO2max. Furthermore, performance (velocity at VO2max, running economy), improved exercise metabolism (lactate threshold), and skeletal muscle levels of mitochondrial proteins were superior in runners versus sedentary controls with similar VO2max. In conclusion subjects with a high amount of PA have more positive metabolic health parameters independent of CRF. PA is thus a good marker against metabolic diseases. PMID:25821340

  15. Time to exhaustion at continuous and intermittent maximal lactate steady state during running exercise.

    Science.gov (United States)

    Dittrich, Naiandra; de Lucas, Ricardo Dantas; Beneke, Ralph; Guglielmo, Luiz Guilherme

    2014-09-01

    The purpose of this study was to determine and compare the time to exhaustion (TE) and the physiological responses at continuous and intermittent (ratio 5:1) maximal lactate steady state (MLSS) in well-trained runners. Ten athletes (32.7 ± 6.9 y, VO2max 61.7 ± 3.9 mL · kg-1 · min-1) performed an incremental treadmill test, three to five 30-min constant-speed tests to determine the MLSS continuous and intermittent (5 min of running, interspaced by 1 min of passive rest), and 2 randomized TE tests at such intensities. Two-way ANOVA with repeated measures was used to compare the changes in physiological variables during the TE tests and between continuous and intermittent exercise. The intermittent MLSS velocity (MLSSint = 15.26 ± 0.97 km/h) was higher than in the continuous model (MLSScon = 14.53 ± 0.93 km/h), while the TE at MLSScon was longer than MLSSint (68 ± 11 min and 58 ± 15 min, P heart rate, ventilation, and rating of perceived exertion presented a significant increase in the last portion of the tests. The results showed a higher tolerance to exercising during MLSScon than during MLSSint in trained runners. Thus, the training volume of an extensive interval session (ratio 5:1) designed at MLSS intensity should take into consideration this higher speed at MLSS and also the lower TE than with continuous exercise.

  16. Acute changes in muscle activation and leg extension performance after different running exercises in elite long distance runners.

    Science.gov (United States)

    Vuorimaa, Timo; Virlander, Rami; Kurkilahti, Pasi; Vasankari, Tommi; Häkkinen, Keijo

    2006-02-01

    This study investigated acute changes in muscle activation and muscular power performance after three different running exercises in elite long-distance runners. Twenty-two nationally and internationally ranked long-distance runners performed first an incremental treadmill running test until exhaustion (MR) and then 40 min continuous (TR) and intermittent (2 min run/2 min rest) (IR) running exercises at an intensity of 80 and 100% of the velocity associated with VO(2max), respectively. Muscle activation and muscular power performance tests (counter-movement jumps, CMJ, and a set of ten maximal half squats from the static starting position with an extra load of 35% of the subjects, one repetition maximum) were performed before and immediately after the runs. The average mechanical power (P) of the half squats was calculated and the root mean square electromyogram (EMGrms) from the vastus lateralis, vastus medialis, gastrocnemius and biceps femoris muscles was recorded simultaneously during the half squat performances. The results showed an acute exercise-induced increase in P (ANOVA time effect, P = 0.000) together with a reduction in EMGrms of the knee extensor muscles (ANOVA time effect, P = 0.000). However, mechanical P expressed as a relative change within the set decreased after MR. In TR the improvement in P correlated positively with the maximal running performance of the runners (P muscles, and may lead to a different coordination strategy in leg extension exercises performed into the vertical direction. After continuous type of running the power improvement correlates positively with maximal endurance running capacity, whereas after intermittent type of running it correlates negatively.

  17. Influência da aptidão aeróbia no running anaerobic sprint test (RAST

    Directory of Open Access Journals (Sweden)

    Vitor Luiz de Andrade

    2013-09-01

    Full Text Available O objetivo do estudo foi verificar a possível influência de diferentes níveis de aptidão aeróbia (VO2MAX sobre os parâmetros do running anaerobic sprint test (RAST. Para isso, 38 indivíduos (Idade = 18,1±2,5 anos, Estatura = 173±1 cm e Massa corporal = 65,1±6,5 kg foram classificados em dois grupos, baixa e elevada aptidão aeróbias (GBA: n=22 e GEA: n=16. O VO2MAX foi determinado por um esforço incremental em esteira rolante até a exaustão voluntária. O RAST foi composto de seis esforços máximos de 35m separados por 10s de intervalo passivo. O VO2MAX foi significativamente diferente entre os grupos (GBA = 51,7±1,9 mL.kg-1.min-1; GEA = 58,6±3,1 mL.kg-1.min-1. A potência média (PM foi significativamente superior no grupo GBA (552,7±132,1 W em relação ao grupo GEA (463,6±132,8 W. O impulso (ImP foi significativamente correlacionado com o VO2MAX no GEA. Pode-se concluir que há um indicativo que o metabolismo aeróbio exerce uma influência na realização do RAST.

  18. The variation after different weeks HIIT and moderate-intensity exercise in rats ’ VO2 max and cardiovascular risk indicator%不同时长 HIIT与中等强度运动后大鼠痹VO2 max及血液心血管风险指标的变化

    Institute of Scientific and Technical Information of China (English)

    王林佳; 苏浩; 梁春瑜; 严翊; 赵岩; 张一民

    2016-01-01

    Purpose :as a new movement ,HIIT ( High‐intensity Interval T raining ) has a better effects on improving cardiorespiratory endurance than moderate training ,but there are less studies on the safety of movement .This study discussion the variation in rats ’ VO2 max and cardiovascular risk index after different time HIIT and moderate exercise .Compared two ways of exercise in improving cardiorespiratory endurance sports as well as the changes in cardiovas‐cular risk indicators ,Clearly which can improve cardiorespiratory endurance effective safety and also provide a theoretical basis for public health movement selection .Methods :120 6‐week‐old male Wistar rats were randomly divided into four groups (N = 30 ):2 weeks (group C ) ,4 weeks(group D) ,6 weeks(group E) ,10 weeks(group F) .Each group was divided into the control ,moderate‐intensity exercise and HIIT three subgroups of 10 rats each .All the rats free to gather the food and drinking water .Sedentary control rats do not exercise ,moderate intensi‐ty and HIIT rats were carried 50min exercise every day ,5times/week .Before the start of training 2 ,4 ,6 ,10 weeks ,Each group of rats were carried out maximal oxygen uptake test .24 hours after test ,rats were intraperitoneal injection by 2% sodium pentobarbital of anesthetized and get Abdominal aortic blood around 8 ml into the anticoagulant tube after centrifugation ,se‐rum to -80℃ under test .The determination of serum creatine kinase (CK ) ,aspertate amin‐otransferase(AST ) ,angiotensin II (AngII) .Different exercise group and the comparison be‐tween different exercise time of group adopt single factor analysis of variance ,the results are expressed as mean ± standard deviation .Results :(1 )after 4 weeks of training ,HIIT rats VO2 max appear stable upward trend but moderate group appears upward trend after 6 weeks . at 10 weeks HIIT group rats’ VO2 max (3 456 .4 ± 335 .427 ml/kg/min) was significantly higher than the control rats (2

  19. EFFECTS OF RUN-UP VELOCITY ON PERFORMANCE, KINEMATICS, AND ENERGY EXCHANGES IN THE POLE VAULT

    Directory of Open Access Journals (Sweden)

    Nicholas P. Linthorne

    2012-06-01

    Full Text Available This study examined the effect of run-up velocity on the peak height achieved by the athlete in the pole vault and on the corresponding changes in the athlete's kinematics and energy exchanges. Seventeen jumps by an experienced male pole vaulter were video recorded in the sagittal plane and a wide range of run-up velocities (4.5-8.5 m/s was obtained by setting the length of the athlete's run-up (2-16 steps. A selection of performance variables, kinematic variables, energy variables, and pole variables were calculated from the digitized video data. We found that the athlete's peak height increased linearly at a rate of 0.54 m per 1 m/s increase in run-up velocity and this increase was achieved through a combination of a greater grip height and a greater push height. At the athlete's competition run-up velocity (8.4 m/s about one third of the rate of increase in peak height arose from an increase in grip height and about two thirds arose from an increase in push height. Across the range of run-up velocities examined here the athlete always performed the basic actions of running, planting, jumping, and inverting on the pole. However, he made minor systematic changes to his jumping kinematics, vaulting kinematics, and selection of pole characteristics as the run-up velocity increased. The increase in run-up velocity and changes in the athlete's vaulting kinematics resulted in substantial changes to the magnitudes of the energy exchanges during the vault. A faster run-up produced a greater loss of energy during the take-off, but this loss was not sufficient to negate the increase in run-up velocity and the increase in work done by the athlete during the pole support phase. The athlete therefore always had a net energy gain during the vault. However, the magnitude of this gain decreased slightly as run-up velocity increased

  20. The reliability of the intermittent critical velocity test and assessment of critical rest interval in men and women.

    Science.gov (United States)

    Fukuda, David H; Smith, Abbie E; Kendall, Kristina L; Hetrick, Robert P; Hames, Ryan L; Cramer, Joel T; Stout, Jeffrey R

    2012-04-01

    The purpose of this study was to examine the reliability of the intermittent critical velocity (ICV) test and assess critical rest interval (CRI) during repeated-sprint exercise. The ICV test is used to examine the linear relationship between total distance and time-to-exhaustion during interval exercise, yielding a repeatable, moderate-intensity parameter (ICV), a high-intensity exhaustive parameter (W'), and CRI. CRI is the theoretical rest period needed to complete a series of repeated bouts of exercise without fatigue. Twenty-four healthy college-aged men (mean ± SD; age 22.7 ± 2.9 years; weight 85.8 ± 15.3 kg; VO(2max) 50.7 ± 8.8 ml/kg/min) and women (mean ± SD; age 21.4 ± 2.3 years; weight 58.9 ± 5.2 kg; VO(2max) 46.4 ± 4.4 ml/kg/min) participants completed two ICV tests (T1 and T2), using 10 s repeated sprints to exhaustion during separate sessions of treadmill running. Linear regression was used to determine ICV and W', while CRI was calculated using the relationship between the number of intervals completed and a variant of ICV. Intraclass correlation coefficients (ICCs) for ICV, W', and CRI were 0.89 (T1 4.42 ± 0.55 m/s; T2 4.34 ± 0.67 m/s), 0.80 (T1 125.6 ± 62.7 m; T2 144.6 ± 65.4 m), and 0.59 (T1 23.9 ± 2.0 s; T2 24.5 ± 2.6 s), respectively. These moderate to high ICC values indicate reliable measurements between ICV trials. Additionally, the evaluation of CRI demonstrated the attainment of a steady-state heart rate (94% of maximum) during a separate session of repeated supramaximal treadmill sprints. The ICV test during treadmill running provides reliable ICV and W' measures, as well as an estimated recovery time via CRI for men and women.

  1. Force-, EMG-, and elasticity-velocity relationships at submaximal, maximal and supramaximal running speeds in sprinters.

    Science.gov (United States)

    Mero, A; Komi, P V

    1986-01-01

    The relationships between ground reaction forces, electromyographic activity (EMG), elasticity and running velocity were investigated at five speeds from submaximal to supramaximal levels in 11 male and 8 female sprinters. Supramaximal running was performed by a towing system. Reaction forces were measured on a force platform. EMGs were recorded telemetrically with surface electrodes from the vastus lateralis and gastrocnemius muscles, and elasticity of the contact leg was evaluated with spring constant values measured by film analysis. Data showed increases in most of the parameters studied with increasing running speed. At supramaximal velocity (10.36 +/- 0.31 m X s-1; 108.4 +/- 3.8%) the relative increase in running velocity correlated significantly (P less than 0.01) with the relative increase in stride rate of all subjects. In male subjects the relative change in stride rate correlated with the relative change of IEMG in the eccentric phase (P less than 0.05) between maximal and supramaximal runs. Running with the towing system caused a decrease in elasticity during the impact phase but this was significant (P less than 0.05) only in the female sprinters. The average net resultant force in the eccentric and concentric phases correlated significantly (P less than 0.05-0.001) with running velocity and stride length in the maximal run. It is concluded that increased neural activation in supramaximal effort positively affects stride rate and that average net resultant force as a specific force indicator is primarily related to stride length and that the values in this indicator may explain the difference in running velocity between men and women.

  2. Mean platelet volume (MPV predicts middle distance running performance.

    Directory of Open Access Journals (Sweden)

    Giuseppe Lippi

    Full Text Available Running economy and performance in middle distance running depend on several physiological factors, which include anthropometric variables, functional characteristics, training volume and intensity. Since little information is available about hematological predictors of middle distance running time, we investigated whether some hematological parameters may be associated with middle distance running performance in a large sample of recreational runners.The study population consisted in 43 amateur runners (15 females, 28 males; median age 47 years, who successfully concluded a 21.1 km half-marathon at 75-85% of their maximal aerobic power (VO2max. Whole blood was collected 10 min before the run started and immediately thereafter, and hematological testing was completed within 2 hours after sample collection.The values of lymphocytes and eosinophils exhibited a significant decrease compared to pre-run values, whereas those of mean corpuscular volume (MCV, platelets, mean platelet volume (MPV, white blood cells (WBCs, neutrophils and monocytes were significantly increased after the run. In univariate analysis, significant associations with running time were found for pre-run values of hematocrit, hemoglobin, mean corpuscular hemoglobin (MCH, red blood cell distribution width (RDW, MPV, reticulocyte hemoglobin concentration (RetCHR, and post-run values of MCH, RDW, MPV, monocytes and RetCHR. In multivariate analysis, in which running time was entered as dependent variable whereas age, sex, blood lactate, body mass index, VO2max, mean training regimen and the hematological parameters significantly associated with running performance in univariate analysis were entered as independent variables, only MPV values before and after the trial remained significantly associated with running time. After adjustment for platelet count, the MPV value before the run (p = 0.042, but not thereafter (p = 0.247, remained significantly associated with running

  3. Force-Time Characteristics and Running Velocity of Male Sprinters During the Acceleration Phase of Sprinting.

    Science.gov (United States)

    Mero, Antti

    1988-01-01

    Investigation of the force-time characteristics of eight male sprinters during the acceleration phase of the sprint start suggested that the braking and propulsion phases occur immediately after the block phase and that muscle strength strongly affects running velocity in the sprint start. (Author/CB)

  4. Footwear and running cardio-respiratory responses.

    Science.gov (United States)

    Rubin, D A; Butler, R J; Beckman, B; Hackney, A C

    2009-05-01

    This study compared cardio-respiratory responses during running wearing a motion control shoe (MC) or a cushioning shoe (CU) in a cross-over single blinded design. Fourteen runners (10F/4M, age=27.3+/-5.1 years, body mass=64.1+/-12.2 kg, height=167.8+/-7.5 cm, VO (2)max=52.3+/-8.8 ml/kg/min) completed a 40-min run at approximately 65% VO (2) max under both shoe conditions. Oxygen uptake (mL/kg/min; L/min), minute ventilation (L/min), respiratory exchange ratio, and heart rate were measured at minutes 8-10, 18-20, 28-30 and 38-40 of exercise. Rating of perceived exertion was obtained at minutes 10, 20, 30 and 40. Two (footwear) by four (time) repeated measures ANOVAs showed no differences between footwear conditions in overall oxygen consumption (MC=36.8+/-1.5 vs. CU=35.3+/-1.4 mL/kg/min, p=0.143), minute ventilation (MC=50.4+/-4 vs. CU=48.5+/-3.8, p=0.147), respiratory exchange ratio (MC=0.90+/-0.01 vs. CU=0.89+/-0.01, p=0.331), heart rate (MC=159+/-3 vs. CU=160+/-3, p=0.926), or rate of perceived exertion. The design of motion control footwear does not appear to affect cardio-respiratory or perceived exertion responses during submaximal running. The findings are specific to the shoes tested. Nonetheless, the outcomes suggest that footwear selection to reduce certain overuse injuries does not increase the work of running.

  5. Lack of influence of muscular performance parameters on spatio-temporal adaptations with increased running velocity.

    Science.gov (United States)

    Roche-Seruendo, Luis E; García-Pinillos, Felipe; Haicaguerre, Joana; Bataller-Cervero, Ana V; Soto-Hermoso, Víctor M; Latorre-Román, Pedro Á

    2017-02-08

    This study aimed to analyse the influence of muscular performance parameters on spatio-temporal gait characteristics during running when gradually increasing speed. 51 recreationally trained male endurance runners (age: 28 ± 8 years) voluntarily participated in this study. Subjects performed a battery of jumping tests (squat jump, countermovement jump, and 20 cm drop jump), and after that, the subjects performed an incremental running test (10 to 20 km/h) on a motorized treadmill. Spatio-temporal parameters were measured using the OptoGait system. Cluster k-means analysis grouped subjects according to the jumping test performance, by obtaining a group of good jumpers (GJ, n = 19) and a group of bad jumpers (BJ, n = 32). With increased running velocity, contact time was shorter, flight time and step length longer, whereas cadence and stride angle were greater (p adaptations between those runners with good jumping ability and those with poor jumping ability. Based on that, it seems that muscular performance parameters do not play a key role in spatio-temporal adaptations experienced by recreational endurance runners with increased velocity. However, taken into consideration the well-known relationship between running performance and neuromuscular performance, the authors suggest that muscular performance parameters would be much more determinant in the presence of fatigue (exhausted condition), or in the case of considering other variables such as running economy or kinetic.

  6. The influence of surface on the running velocities of elite and amateur orienteer athletes.

    Science.gov (United States)

    Hébert-Losier, K; Jensen, K; Mourot, L; Holmberg, H-C

    2014-12-01

    We compared the reduction in running velocities from road to off-road terrain in eight elite and eight amateur male orienteer athletes to investigate whether this factor differentiates elite from amateur athletes. On two separate days, each subject ran three 2-km time trials and three 20-m sprints "all-out" on a road, on a path, and in a forest. On a third day, the running economy and maximal aerobic power of individuals were assessed on a treadmill. The elite orienteer ran faster than the amateur on all three surfaces and at both distances, in line with their better running economy and aerobic power. In the forest, the elites ran at a slightly higher percentage of their 2-km (∼3%) and 20-m (∼4%) road velocities. Although these differences did not exhibit traditional statistical significance, magnitude-based inferences suggested likely meaningful differences, particularly during 20-m sprinting. Of course, cognitive, mental, and physical attributes other than the ability to run on different surfaces are required for excellence in orienteering (e.g., a high aerobic power). However, we suggest that athlete-specific assessment of running performance on various surfaces and distances might assist in tailoring training and identifying individual strengths and/or weaknesses in an orienteer.

  7. Dynamics, velocity and run-out of the giant Storegga slide

    Science.gov (United States)

    de Blasio, F.; Issler, D.; Elverhøi, A.; Harbitz, C. B.; Ilstad, T.; Bryn, P.; Lien, R.; Løvholt, F.

    2003-04-01

    A huge slide (volume of 2400 km^3 and run-out 450 km) was released in the Storegga area off the western coast of Norway during early Holocene, followed by numerous smaller debris flows. We perform numerical simulations of the giant slide using a Bingham model for the clay material. Agreement with present deposit distribution and run-out is found by assuming that the shear resistance between the debris flow and the seabed decreases during the flow, and we suggest sediment remolding or hydroplaning as possible explanations. Debris velocities are predicted and possible applications to the associated tsunami event are investigated.

  8. A simple method for measuring power, force, velocity properties, and mechanical effectiveness in sprint running.

    Science.gov (United States)

    Samozino, P; Rabita, G; Dorel, S; Slawinski, J; Peyrot, N; Saez de Villarreal, E; Morin, J-B

    2016-06-01

    This study aimed to validate a simple field method for determining force- and power-velocity relationships and mechanical effectiveness of force application during sprint running. The proposed method, based on an inverse dynamic approach applied to the body center of mass, estimates the step-averaged ground reaction forces in runner's sagittal plane of motion during overground sprint acceleration from only anthropometric and spatiotemporal data. Force- and power-velocity relationships, the associated variables, and mechanical effectiveness were determined (a) on nine sprinters using both the proposed method and force plate measurements and (b) on six other sprinters using the proposed method during several consecutive trials to assess the inter-trial reliability. The low bias (<5%) and narrow limits of agreement between both methods for maximal horizontal force (638 ± 84 N), velocity (10.5 ± 0.74 m/s), and power output (1680 ± 280 W); for the slope of the force-velocity relationships; and for the mechanical effectiveness of force application showed high concurrent validity of the proposed method. The low standard errors of measurements between trials (<5%) highlighted the high reliability of the method. These findings support the validity of the proposed simple method, convenient for field use, to determine power, force, velocity properties, and mechanical effectiveness in sprint running.

  9. Energy expenditure and cardiorespiratory responses at the transition between walking and running.

    Science.gov (United States)

    Mercier, J; Le Gallais, D; Durand, M; Goudal, C; Micallef, J P; Préfaut, C

    1994-01-01

    We investigated whether the spontaneous transition between walking and running during moving with increasing speed corresponds to the speed at which walking becomes less economical than running. Seven active male subjects [mean age, 23.7 (SEM 0.7) years, mean maximal oxygen uptake (VO2max), 57.5 (SEM 3.3) ml.kg-1.min-1, mean ventilatory threshold (VTh), 37.5 (SEM3) ml.kg-1.min-1] participated in this study. Each subject performed four exercise tests separated by 1-week intervals: test 1, VO2max and VTh were determined; test 2, the speed at which the transition between walking and running spontaneously occurs (ST) during increasing speed (increases of 0.5 km.h-1 every 4 min from 5 km.h-1) was determined; test 3, the subjects were constrained to walk for 4 min at ST, at ST +/- 0.5 km.h-1 and at ST +/- 1 km.h-1; and test 4, the subjects were constrained to run for 4 min at ST, at ST +/- 0.5 km.h-1 and at ST +/- 1 km.h-1. During exercise oxygen uptake (VO2), heart rate (HR), ventilation (VE), ventilatory equivalents for oxygen and carbon dioxide (VE/VO2, VE/VCO2), respiratory exchange ratio (R), stride length (SL), and stride frequency (SF) were measured.(ABSTRACT TRUNCATED AT 250 WORDS)

  10. A Method for Determination of in Run-Up Front Velocities on Dikes in Oblique and Short-Crested Waves

    DEFF Research Database (Denmark)

    Andersen, Thomas Lykke; Nørgaard, Jørgen Harck; Burcharth, Hans F.

    2011-01-01

    This paper presents a physical model test study to improve description of run-up events on dikes in oblique long and short-crested waves in terms of flow depth, flow velocities and overtopping. The paper focus on the flow velocities and a new method is proposed for determining flow velocities...

  11. EFFECTS OF A SAND RUNNING SURFACE ON THE KINEMATICS OF SPRINTING AT MAXIMUM VELOCITY

    Directory of Open Access Journals (Sweden)

    P E Alcaraz

    2011-05-01

    Full Text Available Performing sprints on a sand surface is a common training method for improving sprint-specific strength. For maximum specificity of training the athlete’s movement patterns during the training exercise should closely resemble those used when performing the sport. The aim of this study was to compare the kinematics of sprinting at maximum velocity on a dry sand surface to the kinematics of sprinting on an athletics track. Five men and five women participated in the study, and flying sprints over 30 m were recorded by video and digitized using biomechanical analysis software. We found that sprinting on a sand surface was substantially different to sprinting on an athletics track. When sprinting on sand the athletes tended to ‘sit’ during the ground contact phase of the stride. This action was characterized by a lower centre of mass, a greater forward lean in the trunk, and an incomplete extension of the hip joint at take-off. We conclude that sprinting on a dry sand surface may not be an appropriate method for training the maximum velocity phase in sprinting. Although this training method exerts a substantial overload on the athlete, as indicated by reductions in running velocity and stride length, it also induces detrimental changes to the athlete’s running technique which may transfer to competition sprinting.

  12. Índices fisiológicos associados com a "performance" aeróbia em corredores de "endurance": efeitos da duração da prova Índices fisiológicos asociados a la "performance" aerobia en competidores de "endurance": efectos de la duración de la prueba Physiological indexes associated with aerobic performance in endurance runners: effects of race duration

    Directory of Open Access Journals (Sweden)

    Benedito Sérgio Denadai

    2004-10-01

    .000m (17,9 ± 0,9 fueron significantemente diferentes. La regresión múltiple stepwise mostró que el LAn fue el único elemento de predicción de la performance de la v5.000m, explicando el 50% de la variación de esta performance. Para la v1.500m, el Tlim y la vVO2max explicaron el 88% de la variación de la performance. Con base en nuestros resultados, se puede concluir que la validez de los índices fisiológicos (VO2max, vVO2max, Tlim, EC y LAn, para la predicción de la performance aerobia de atletas de endurance depende de la distancia de la prueba (1.500 x 5.000m analizada.The aim of this study was to assess the validity of the maximal oxygen uptake (VO2max, the velocity at VO2max (vVO2max, time to exhaustion at vVO2max (Tlim, running economy (RE and anaerobic threshold (AnT to predict the aerobic performance of the endurance athletes. Fourteen well-trained long-distance runners (33.4 ± 4.4 yr.; 62.7 ± 4.3 kg; 166.1 ± 5.0 cm; VO2max = 60.4 ± 5.9 ml.kg-1.min-1 underwent the following tests: a simulated competitions in the distances of 1500 and 5000 m and; b laboratory treadmill tests to determine their VO2max, vVO2max, Tlim, EC and AnT. The velocities (km/h at vVO2max (18.7 + 0.8, LAn (17.3 + 1.1 v1500 m (19.9 + 0.8 and v5000 m (17.9 + 0.9 were significantly different. A stepwise multiple-regression analysis revealed that AnT alone was the best single predictor of v-5000 m and explained 50% of the variability in 5000 m running velocity. For v1.500 m, Tlim and vVO2max explained 88 % of the variability of the performance. We conclude that, in a group of well-trained long-distance runners, the validity of the physiological indexes (VO2max, vVO2max, Tlim, EC e LAn to predict the aerobic performance is dependent of the distance (1500 x 5000 m analyzed.

  13. Decrease of muscle fiber conduction velocity correlates with strength loss after an endurance run.

    Science.gov (United States)

    Boccia, Gennaro; Dardanello, Davide; Tarperi, Cantor; Rosso, Valeria; Festa, Luca; La Torre, Antonio; Pellegrini, Barbara; Schena, Federico; Rainoldi, Alberto

    2017-02-01

    Monitoring surface electromyographic (EMG) signals can provide useful insights for characterizing muscle fatigue, which is defined as an exercise-induced strength loss. This experiment investigated the muscle fiber conduction velocity (CV) changes induced by an endurance run. The day before and immediately after a half-marathon run (21.097 km) 11 amateur runners performed maximum voluntary contractions (MVCs) of knee extensor muscles. During the MVC, multichannel EMG was recorded from the vastus lateralis and EMG amplitude and CV were calculated. After the run, knee extensors showed a decreased strength (-13  ±  9%, p  =  0.001) together with a reduction in EMG amplitude (-13  ±  10%, p  =  0.003) and in CV (-6  ±  8%, p  =  0.032). Knee extensor strength loss positively correlated with vastus lateralis CV differences (r  =  0.76, p  =  0.006). Thus, the exercises-induced muscle fatigue was associated not only with a decrease in EMG amplitude, but also with a reduction in CV. This finding suggests that muscle fibers with higher CV (i.e. those with greater fiber size) were the most impaired during strength production after an endurance run.

  14. The metabolic relation between hypoxanthine and uric acid in man following maximal short-distance running.

    Science.gov (United States)

    Westing, Y H; Ekblom, B; Sjödin, B

    1989-11-01

    This study was performed to assess the metabolic relation between hypoxanthine and uric acid following short-distance maximal running. Eleven trained males, mean age 22 years (16-31), were instructed to run 800 m in the shortest time possible. Blood samples were collected before warm-up, before the run, immediately after the run and periodically up to 24 h following the run. Blood lactate was determined after warm-up, and at 5, 10, and 30 min following the run. Mean VO2 max for the subjects was 65.8 (4.7) (SD) ml kg-1 min-1 and mean oxygen demand for the running was 118 (8)% of VO2 max. Plasma hypoxanthine levels rose from 3.3 (1.4) to a peak of 48.2 (19.0) mumol l-1 at 20 min following the run and at 180 min had almost returned to pre-run levels. Plasma uric acid levels rose from a pre-run value of 267 (34) to a peak value of 431 (87) mumol l-1 at 45 min following the run. Uric acid concentrations had not returned to normal at 10 h following the run. The blood lactate level peaked at 5 min with 13.7 (2.0) mmol l-1. The results obtained in this study indicate a metabolic relationship between the formation of hypoxanthine and the formation of uric acid. The data also indicate that xanthine oxidase is active following short-distance intensive running.

  15. INDIRECT CALORIMETRY DURING ULTRADISTANCE RUNNING: A CASE REPORT

    Directory of Open Access Journals (Sweden)

    Charles L. Dumke

    2006-12-01

    Full Text Available The purpose was to determine the energy expenditure during ultradistance trail running. A portable metabolic unit was carried by a male subject for the first 64.5 km portion of the Western States 100 running race. Calibrations were done with known gases and volumes at ambient temperature, humidity and pressure (23-40.5 °C and 16-40% respectively. Altitude averaged 1692.8 ± 210 m during data collection. The male subject (36 yrs, 75 kg, VO2max of 67.0 ml·kg-1·min-1 had an average (mean ± SD heart rate of 132 ± 9 bpm, oxygen consumption of 34.0 ± 6.8 ml·kg-1·min-1, RER of 0.91 ± 0.04, and VE of 86.0 ± 14.3 L·min-1 during the 21.7 km measuring period. This represented an average of 51% VO2max and 75% heart rate maximum. Energy expenditure was 12.6 ± 2.5 kcals·min-1, or 82.7 ± 16.6 kcals·km-1 (134 ± 27 kcals·mile-1 at 68.3 ± 12.5% carbohydrate. Extrapolation of this data would result in an energy expenditure of >13,000 kcals for the 160 km race, and an exogenous carbohydrate requirement of >250 kcal·hr-1. The energy cost of running for this subject on separate, noncompetitive occasions ranged from 64.9 ± 8.5 to 74.4 ± 5.5 kcals·km-1 (105 ± 14 to 120 ± 9 kcals·mile-1. Ultradistance trail running increases energy expenditure above that of running on nonundulating terrain, which may result in underestimating energy requirements during these events and subsequent undernourishment and suboptimal performance.

  16. Does Step Length Adjustment Determine Take-Off Accuracy and Approach Run Velocity in Long and Triple Jumps?

    National Research Council Canada - National Science Library

    Makaruk Hubert; Marcin Starzak; Jerzy Sadowski

    2015-01-01

    Purpose. While take-off accuracy and approach run velocity are known determinants of long and triple jump performance, the interaction of these factors with step length adjustment (SLA) is not as clear. Methods...

  17. Determination of maximum aerobic velocity by a five minute test with reference to running world records. A theoretical approach.

    Science.gov (United States)

    Chamoux, A; Berthon, P; Laubignat, J F

    1996-01-01

    Field measurement of the maximal aerobic velocity (MAV) is closely linked to effort-duration then to the used protocol. We construct the relationship between running speed and running-duration logarithm from running world records. It appears a noteworthy point at 4.97 minutes, to be suggested as MAV duration point. By agreement, MAV could be measured on field by a five minute test whatever the sport may be.

  18. Prediction of Maximum Oxygen Consumption from Walking, Jogging, or Running.

    Science.gov (United States)

    Larsen, Gary E.; George, James D.; Alexander, Jeffrey L.; Fellingham, Gilbert W.; Aldana, Steve G.; Parcell, Allen C.

    2002-01-01

    Developed a cardiorespiratory endurance test that retained the inherent advantages of submaximal testing while eliminating reliance on heart rate measurement in predicting maximum oxygen uptake (VO2max). College students completed three exercise tests. The 1.5-mile endurance test predicted VO2max from submaximal exercise without requiring heart…

  19. Prediction of Maximum Oxygen Consumption from Walking, Jogging, or Running.

    Science.gov (United States)

    Larsen, Gary E.; George, James D.; Alexander, Jeffrey L.; Fellingham, Gilbert W.; Aldana, Steve G.; Parcell, Allen C.

    2002-01-01

    Developed a cardiorespiratory endurance test that retained the inherent advantages of submaximal testing while eliminating reliance on heart rate measurement in predicting maximum oxygen uptake (VO2max). College students completed three exercise tests. The 1.5-mile endurance test predicted VO2max from submaximal exercise without requiring heart…

  20. Running kinematics and shock absorption do not change after brief exhaustive running.

    Science.gov (United States)

    Abt, John P; Sell, Timothy C; Chu, Yungchien; Lovalekar, Mita; Burdett, Ray G; Lephart, Scott M

    2011-06-01

    Because of the nature of running, the forces encountered require a proper coordination of joint action of the lower extremity to dissipate the ground reaction forces and accelerations through the kinetic chain. Running-related muscle fatigue may reduce the shock absorbing capacity of the lower extremity and alter running kinematics. The purpose of this study was to determine if a bout of exhaustive running at a physiologically determined high intensity, changes running kinematics, impact accelerations, and alters shock attenuating capabilities. It was hypothesized that as a result of fatigue induced by an exhaustive run, running kinematics, impact accelerations at the head and shank, acceleration reduction, and shock attenuation would change. A within-subject, repeated-measures design was used for this study. Twelve healthy, competitive male and female distance runners participated. Subjects performed 2 testing sessions consisting of a VO2max treadmill protocol to determine the heart rate at ventilatory threshold and a fatigue-inducing running bout at the identified ventilatory threshold heart rate. Kinematic data included knee flexion, pronation, time to maximum knee flexion, and time to maximum pronation. Acceleration data included shank acceleration, head acceleration, and shock attenuation. No significant differences resulted for the kinematic or acceleration variables. Although the results of this study do not support the original hypotheses, the influence of running fatigue on kinematics and accelerations remains inconclusive. Future research is necessary to examine fatigue-induced changes in running kinematics and accelerations and to determine the threshold at which point the changes may occur.

  1. Intensity related changes of running economy in recreational level distance runners.

    Science.gov (United States)

    Engeroff, Tobias; Bernardi, Andreas; Niederer, Daniel; Wilke, Jan; Vogt, Lutz; Banzer, Winfried

    2017-09-01

    Running economy (RE) is often described as a key demand of running performance. The variety of currently used assessment methods with different running intensities and outcomes restricts interindividual comparability of RE in recreational level runners. The purpose of this study was to compare the influence of RE, assessed as oxygen cost (OC) and caloric unit cost (CUC), on running speed at individual physiological thresholds. Eighteen recreational runners performed: 1) a graded exercise test to estimate first ventilatory threshold (VT1), respiratory compensation point (RCP) and maximal oxygen uptake (VO2max); 2) discontinuous RE assessment to determine relative OC in milliliters per kilogram per kilometer (mL/kg/km) and CUC in kilocalories per kilogram per kilometer (kcal/kg/km) at three different running intensities: VT1, RCP and at a third standardized reference point (TP) in between. OC (mL/kg/km; at VT1: 235.4±26.2; at TP: 227.8±23.4; at RCP: 224.9±21.9) and CUC (kcal/kg/km at VT1: 1.18±0.13; at TP: 1.14±0.12; at RCP: 1.13±0.11) decreased with increasing intensities (P≤0.01). Controlling for the influence of sex OC and CUC linearly correlated with running speed at RCP and VO2max (P≤0.01). RE, even assessed at low intensity, is strongly related to running performance in recreational athletes. Both calculation methods used (OC and CUC) are sensitive for monitoring intensity related changes of substrate utilization. RE values decreased with higher running intensity indicating an increase of anaerobic and subsequent decrease of aerobic substrate utilization.

  2. Effect of beta-alanine supplementation on the onset of blood lactate accumulation (OBLA during treadmill running: Pre/post 2 treatment experimental design

    Directory of Open Access Journals (Sweden)

    Misic Mark

    2010-05-01

    Full Text Available Abstract Background β-Alanine (βA has been shown to improve performance during cycling. This study was the first to examine the effects of βA supplementation on the onset of blood lactate accumulation (OBLA during incremental treadmill running. Methods Seventeen recreationally-active men (mean ± SE 24.9 ± 4.7 yrs, 180.6 ± 8.9 cm, 79.25 ± 9.0 kg participated in this randomized, double-blind, placebo-controlled pre/post test 2-treatment experimental design. Subjects participated in two incremental treadmill tests before and after 28 days of supplementation with either βA (6.0 g·d-1(βA, n = 8 or an equivalent dose of Maltodextrin as the Placebo (PL, n = 9. Heart rate, percent heart rate maximum (%HRmax, %VO2max@OBLA (4.0 mmol.L-1 blood lactate concentration and VO2max (L.min-1 were determined for each treadmill test. Friedman test was used to determine within group differences; and Mann-Whitney was used to determine between group differences for pre and post values (p Results The βA group experienced a significant rightward shift in HR@OBLA beats.min-1 (p 2max@OBLA increased (p 2max (L.min-1 decreased (p Conclusions βA supplementation for 28 days enhanced sub-maximal endurance performance by delaying OBLA. However, βA supplemented individuals had a reduced aerobic capacity as evidenced by the decrease in VO2max values post supplementation.

  3. How muscle fiber lengths and velocities affect muscle force generation as humans walk and run at different speeds.

    Science.gov (United States)

    Arnold, Edith M; Hamner, Samuel R; Seth, Ajay; Millard, Matthew; Delp, Scott L

    2013-06-01

    The lengths and velocities of muscle fibers have a dramatic effect on muscle force generation. It is unknown, however, whether the lengths and velocities of lower limb muscle fibers substantially affect the ability of muscles to generate force during walking and running. We examined this issue by developing simulations of muscle-tendon dynamics to calculate the lengths and velocities of muscle fibers from electromyographic recordings of 11 lower limb muscles and kinematic measurements of the hip, knee and ankle made as five subjects walked at speeds of 1.0-1.75 m s(-1) and ran at speeds of 2.0-5.0 m s(-1). We analyzed the simulated fiber lengths, fiber velocities and forces to evaluate the influence of force-length and force-velocity properties on force generation at different walking and running speeds. The simulations revealed that force generation ability (i.e. the force generated per unit of activation) of eight of the 11 muscles was significantly affected by walking or running speed. Soleus force generation ability decreased with increasing walking speed, but the transition from walking to running increased the force generation ability by reducing fiber velocities. Our results demonstrate the influence of soleus muscle architecture on the walk-to-run transition and the effects of muscle-tendon compliance on the plantarflexors' ability to generate ankle moment and power. The study presents data that permit lower limb muscles to be studied in unprecedented detail by relating muscle fiber dynamics and force generation to the mechanical demands of walking and running.

  4. Influence of running and walking on hormonal regulators of appetite in women.

    Science.gov (United States)

    Larson-Meyer, D Enette; Palm, Sonnie; Bansal, Aasthaa; Austin, Kathleen J; Hart, Ann Marie; Alexander, Brenda M

    2012-01-01

    Nine female runners and ten walkers completed a 60 min moderate-intensity (70% VO(2)max) run or walk, or 60 min rest in counterbalanced order. Plasma concentrations of the orexogenic peptide ghrelin, anorexogenic peptides peptide YY (PYY), glucagon-like peptide-1 (GLP-1), and appetite ratings were measured at 30 min interval for 120 min, followed by a free-choice meal. Both orexogenic and anorexogenic peptides were elevated after running, but no changes were observed after walking. Relative energy intake (adjusted for cost of exercise/rest) was negative in the meal following running (-194 ± 206 kcal) versus walking (41 ± 196 kcal) (P = 0.015), although both were suppressed (P regulating hormones rather than change in a single gut peptide.

  5. Effect of preexercise meals with different glycemic indices and loads on metabolic responses and endurance running.

    Science.gov (United States)

    Chen, Ya Jun; Wong, Stephen H; Wong, Chun Kwok; Lam, Ching Wan; Huang, Ya Jun; Siu, Parco M

    2008-06-01

    This study examined the effect of ingesting 3 isocaloric meals with different glycemic indices (GI) and glycemic loads (GL) 2 hr before exercise on metabolic responses and endurance running performance. Eight male runners completed 3 trials in a randomized order, separated by at least 7 days. Carbohydrate (CHO) content (%), GI, and GL were, respectively, 65%, 79, and 82 for the high-GI/high-GL meal (H-H); 65%, 40, and 42 for the low-GI/low-GL meal (L-L); and 36%, 78, and 44 for the high-GI/low-GL meal (H-L). Each trial consisted of a 1-hr run at 70% VO2max, followed by a 10-km performance run. Low-GL diets (H-L and L-L) were found to induce smaller metabolic changes during the postprandial period and during exercise, which were characterized by a lower CHO oxidation in the 2 trials (p metabolic responses.

  6. Cytoplasmic dynein binding, run length, and velocity are guided by long-range electrostatic interactions.

    Science.gov (United States)

    Li, Lin; Alper, Joshua; Alexov, Emil

    2016-08-17

    Dyneins are important molecular motors involved in many essential biological processes, including cargo transport along microtubules, mitosis, and in cilia. Dynein motility involves the coupling of microtubule binding and unbinding to a change in the configuration of the linker domain induced by ATP hydrolysis, which occur some 25 nm apart. This leaves the accuracy of dynein stepping relatively inaccurate and susceptible to thermal noise. Using multi-scale modeling with a computational focusing technique, we demonstrate that the microtubule forms an electrostatic funnel that guides the dynein's microtubule binding domain (MTBD) as it finally docks to the precise, keyed binding location on the microtubule. Furthermore, we demonstrate that electrostatic component of the MTBD's binding free energy is linearly correlated with the velocity and run length of dynein, and we use this linearity to predict the effect of mutating each glutamic and aspartic acid located in MTBD domain to alanine. Lastly, we show that the binding of dynein to the microtubule is associated with conformational changes involving several helices, and we localize flexible hinge points within the stalk helices. Taken all together, we demonstrate that long range electrostatic interactions bring a level of precision to an otherwise noisy dynein stepping process.

  7. Cross-training and periodization in running.

    Science.gov (United States)

    Brennan, D K; Wilder, R P

    1996-01-01

    Understanding the principles of cross-training and periodization will assist the coach and team physician in designing training programs that maximize performance while minimizing risk of injury. Cross-training is defined as simultaneous training for two or more sports or the use of multiple modes of training to enhance performance in one particular sport. This manuscript will review the benefits of three commonly used forms of cross training, deep water running, cycling and swimming, on running, training and performance. Periodization refers to the process of designing a progressive and appropriate training plan in order to optimize performance, yet minimize injury related to overtraining. The main structural components for periodization are macrocycles, mesocycles and microcycles. Physiological determinants for distance running performance, including VO2 max, lactate threshold and running economy, are presented as key components for the design of endurance training programs. Training intensity can be prescribed or monitored using running speed, heart rate, and rating of perceived exertion (RPE). The clinician must often make recommendations regarding the appropriate level of training or offer an alternative. By understanding the principles of cross-training and periodization, the clinician can assist the coach or athlete in preventing injury as well as assisting the attainment of peak performance.

  8. The effects of prior cycling and a successive run on respiratory muscle performance in triathletes.

    Science.gov (United States)

    Boussana, A; Galy, O; Hue, O; Matecki, S; Varray, A; Ramonatxo, M; Le Gallais, D

    2003-01-01

    The aim of the present study was to compare the effects of prior cycling and a successive run on respiratory muscle performance during a cycle-run succession as performed in the triathlon. We hypothesized that despite the moderate intensity of exercise and the absence of exhaustion, the crouched cycling position would induce a decrease in respiratory muscle performance that would be reversed by the successive vertical run position. Ten male triathletes (22.6 +/- 1.1 yr) performed a four-trial protocol: (1) an incremental cycle test to assess maximal oxygen uptake (VO2max), (2) 20 min of cycling (C), (3) 20 min of running (R), and (4) 20 min of cycling followed by 20 min of running (C-R). Trials 2, 3 and 4 were performed at the same metabolic intensity, i. e., 75 % of VO2max. Respiratory muscle force was assessed by measuring maximal expiratory (P(Emax)) and inspiratory (P(Imax)) pressures from the functional residual capacity (FRC) before and 10 min after C, R, and C-R. Respiratory muscle endurance was assessed one day before and 30 min after C, R, and C-R, by measuring the time limit (T(lim)), which corresponds to the length of time a respiratory load can be sustained before the process of fatigue develops sufficiently to cause task failure. The results showed a similar significant decrease in P(Imax) (132.4 +/- 4.9 versus 125.7 +/- 5.6 cm H2O, p 0.05). We concluded that moderate intensity exercise not performed to exhaustion induced a decrease in respiratory muscle performance. Moreover, the respiratory muscle fatigue induced by prior cycling was maintained, and neither reversed nor worsened, by the successive run.

  9. A Paradigm of Uphill Running

    Science.gov (United States)

    Padulo, Johnny; Powell, Douglas; Milia, Raffaele; Ardigò, Luca Paolo

    2013-01-01

    The biomechanical management of bioenergetics of runners when running uphill was investigated. Several metabolic and mechanical variables have been studied simultaneously to spread light on the locomotory strategy operated by humans for effective locomotion. The studied variables were: heart rate, heart rate variability, oxygen intake and blood lactate, metabolic cost, kinematics, ground reaction force and muscular activity. 18 high-level competitive male runners ran at 70% VO2max on different uphill slope conditions: 0%, 2% and 7%. Modifications were significant in almost all variables studied, and were more pronounced with increasing incline. Step frequency/length and ground reaction force are adjusted to cope with both the task of uphill progression and the available (limited) metabolic power. From 0% to 7% slope, step frequency and ground reaction force and metabolic cost increased concurrently by 4%, 12% and 53%, respectively (with a 4% step length decrease as well). It is hypothesised that this biomechanical management is allowed by an environment-body communication performed by means of specific muscular activity. PMID:23874850

  10. Caffeine stimulates voluntary wheel running in mice without increasing aerobic capacity.

    Science.gov (United States)

    Claghorn, Gerald C; Thompson, Zoe; Wi, Kristianna; Van, Lindsay; Garland, Theodore

    2017-03-01

    The "energy drink" Red Bull and the "sports drink" Gatorade are often marketed to athletes, with claims that they cause performance gains. However, both are high in sugars, and also consumed by non-athletes. Few studies have addressed the effects of these drinks or their biologically active components in rodent exercise models. We used three experiments to test effects on both voluntary exercise behavior and maximal aerobic capacity in lines of mice known to differ in "athletic" traits. Mice from four replicate High Runner (HR) lines have been selectively bred for voluntary running on wheels, and run approximately three times as many revolutions per day as do mice from four non-selected Control (C) lines. HR mice also have higher endurance and maximal oxygen consumption (VO2max) during forced treadmill exercise. In Experiment 1, we tested the hypothesis that Gatorade or Red Bull might cause or allow mice to increase their voluntary wheel running. On days 5 and 6 of 6days of wheel access, as is used to select breeders, HR mice ran 3.3-fold more than C, and females ran 1.2-fold more than males, with no linetype by sex interaction. On day 7, mice were administered Gatorade, Red Bull or tap water. During the subsequent 19-hour period, Gatorade had no statistical effect on running, but Red Bull significantly increased distance run by both sexes and in both HR and C lines. The increase in distance run caused by Red Bull was attributable to time spent running, not an increase in mean (or maximum) speed. As previous studies have found that sucrose alone does not generally increase wheel running, we tested two other active ingredients in Red Bull, caffeine and taurine, in Experiment 2. With a similar testing protocol, caffeine alone and caffeine+taurine increased running by about half the magnitude of Red Bull. In Experiment 3, we tested the hypothesis that Red Bull or caffeine alone can increase physiological performance ability during aerobic exercise, measured as VO2max

  11. Effects of High Velocity Elastic Band versus Heavy Resistance Training on Hamstring Strength, Activation, and Sprint Running Performance.

    Science.gov (United States)

    Janusevicius, Donatas; Snieckus, Audrius; Skurvydas, Albertas; Silinskas, Viktoras; Trinkunas, Eugenijus; Cadefau, Joan Aureli; Kamandulis, Sigitas

    2017-06-01

    Hamstring muscle injuries occur during high-speed activities, which suggests that muscular strength at high velocities may be more important than maximal strength. This study examined hamstring adaptations to training for maximal strength and for strength at high velocities. Physically active men (n = 25; age, 23.0 ± 3.2 years) were randomly divided into: (1) a resistance training (RT, n = 8) group, which performed high-load, low-velocity concentric-eccentric hamstring contractions; (2) a resistance training concentric (RTC; n = 9) group, which performed high-load, low-velocity concentric-only hamstring contractions; and (3) a high-velocity elastic band training (HVT, n = 8) group, which performed low-load, high-velocity concentric-eccentric hamstring contractions. Pre- and posttraining tests included hamstring strength on a hamstring-curl apparatus, concentric knee extension-flexion at 60°/s, 240°/s, and 450°/s, eccentric knee flexion at 60°/s and 240°/s, hamstring and quadriceps coactivation, knee flexion and extension frequency in the prone position, and 30-m sprint running speed from a stationary start and with a running start. Knee flexor torque increased significantly by 21.1% ± 8.1% in the RTC group and 16.2% ± 4.2% in the RT group (p training at high velocities is superior to traditional heavy resistance training for increasing knee flexor strength at high velocities, movement frequency, and sprint running performance. These findings also indicate that traditional training approaches are effective for increasing knee flexor strength and reducing knee extensor coactivation, but this outcome is limited to low and moderate speeds.

  12. Palm cooling does not improve running performance.

    Science.gov (United States)

    Scheadler, C M; Saunders, N W; Hanson, N J; Devor, S T

    2013-08-01

    The aim of this study was to test the efficacy of the BEX Runner palm cooling device during a combination of exercise and environmental heat stress. Twelve subjects completed two randomly ordered time-to-exhaustion runs at 75% VO2max, 30 °C, and 50% relative humidity with and without palm cooling. Time to exhaustion runs started once the warm-up had elicited a core temperature of 37.5 °C. Heart rate, Rating of Perceived Exertion, Feeling Scale, and core temperature were recorded at 2-min intervals during each run. Time to exhaustion was longer in control than treatment (46.7±31.1 vs. 41.3±26.3 min, respectively, prate-of-rise of core temperature was not different between control and treatment (0.047 vs. 0.048 °C · min-1, respectively). The use of the BEX Runner palm cooling device during a run in hot conditions did not eliminate or even attenuate the rise in core temperature. Exercise time in hot conditions did not increase with the use of the palm cooling device and time to exhaustion was reduced. © Georg Thieme Verlag KG Stuttgart · New York.

  13. A protocol of intermittent exercise (shuttle runs) to train young basketball players.

    Science.gov (United States)

    Zadro, Ivan; Sepulcri, Luigino; Lazzer, Stefano; Fregolent, Rudy; Zamparo, Paola

    2011-06-01

    The purpose of this study was to set up a protocol of intermittent exercise to train young basketball players. Twenty-one players were asked to complete (a) an incremental test to determine maximal oxygen uptake (VO2max), the speed at the ventilatory threshold (vthr) and the energy cost of "linear" running (Cr) and (b) an intermittent test composed of 10 shuttle runs of 10-second duration and 30-seconds of recovery (total duration: about 6 minutes). The exercise intensity (the running speed, vi) was set at 130% of vthr. During the intermittent tests, oxygen uptake (VO2) and blood lactate concentration (Lab) were measured. The average pretraining VO2 calculated for a single bout (131 ± 9 ml · min(-1) kg(-1)) was about 2.4 times greater than the subjects' measured VO2max (54.7 ± 4.6 ml · min(-1) · kg(-1)). The net energy cost of running (9.2 ± 0.9 J · m(-1) · kg(-1)) was about 2.4 times higher than that measured at constant "linear" speed (3.9 ± 0.3 J · m(-1) · kg(-1)). The intermittent test was repeated after 7 weeks of training: 9 subjects (control group [CG]) maintained their traditional training schedule, whereas for 12 subjects (experimental group [EG]) part of the training was replaced by intermittent exercise (the same shuttle test as described above). After training, the VO2 measured during the intermittent test was significantly reduced (p young basketball players.

  14. The influence of surface on the running velocities of elite and amateur orienteer athletes

    DEFF Research Database (Denmark)

    Hébert-Losier, K; Jensen, Kurt; Mourot, L

    2014-01-01

    . Of course, cognitive, mental, and physical attributes other than the ability to run on different surfaces are required for excellence in orienteering (e.g., a high aerobic power). However, we suggest that athlete-specific assessment of running performance on various surfaces and distances might assist...

  15. 无训练年轻女性骑车与跑步的脂肪氧化动力学及最大脂肪氧化研究%Fat Oxidation Kinetics and Maximal Fat Oxidation of Untrained Young Women during Cycling and Running

    Institute of Scientific and Technical Information of China (English)

    张勇; 李之俊

    2013-01-01

    Objective The aim of the study is to compare the fat oxidation kinetics,exercise intensity eliciting maximal fat oxidation (Fatmax) and maximal fat oxidation rate (MFO) of untrained young women during cycling and running.Methods 12 healthy untrained young women performed two incremental exercise tests respectively on a cycle ergometer and a treadmill,and the gas metabolism data in the last 30 seconds of each load were measured to calculate fat oxidation rate,and then a 3rd polynomial fitting curve was used to determine fat oxidation kinetics curve,Fatmax and MFO.Results As exercise intensity increased,fat oxidation rate tended to increase first and then decrease.The higher levels of fat oxidation rate was seen in cycling at 50%-60% VO2max (4.48~4.68 mg/min/kg),and in running at 50%-65% VO2max(6.36~6.67 mg/min/kg).Fat oxidation rates were significantly higher during the running than the cycling at the same intensity,and Fatmax and MFO were significantly higher during running than cycling (56.51±2.50%VO2max vs 53.18±3.25%VO2max,P < 0.05;6.71±1.15 mg/min/kg vs 4.74±1.67 mg/min/kg,P < 0.001).The intensity,at which fat oxidation more than 95%MFO,were 44.86~60.60%VO2max for cycling and 48.21%~55.41%VO2max for running.Conclusion Fat oxidation rates,Fatmax and MFO were higher during running than cycling at the same intensity,suggesting that running could be better than cycling in the exercise intervention for obesity,diabetes and others associated with fat metabolism disorder.%目的:比较无训练年轻女性骑车与跑步的脂肪氧化动力学、最大脂肪氧化强度(Fatmax)和最大脂肪氧化率(MFO)的差异.方法:12名无训练年轻女性采用递增负荷模式分别完成自行车测试和跑台测试,测定每级负荷运动过程中机体的气体代谢指标,采用每级负荷后30秒气体代谢数据计算脂肪氧化率,通过3阶数多项式拟合曲线确定脂肪氧化动力曲线及Fatmax和MFO.结果:运动

  16. Study on control method of running velocity for the permanent magnet-HTSC hybrid magnetically levitated conveyance system

    Energy Technology Data Exchange (ETDEWEB)

    Nishio, R.; Ikeda, M.; Sasaki, R. [Kansai University, 3-3-35 Yamate-cho, Suita, Osaka 564-8680 (Japan); Ohashi, S., E-mail: ohashi@kansai-u.ac.jp [Kansai University, 3-3-35 Yamate-cho, Suita, Osaka 564-8680 (Japan)

    2011-11-15

    The hybrid magnetically levitated carrying system is developed. Control method of running velocity of the carrier is studied. Running velocity is controlled by current of the propulsion coils. Propulsion characteristcs are improved. We have developed the magnetically levitated carrying system. In this system, pinning force of high temperature bulk super conductor (HTSC) is used for the levitation and guidance. Four HTSCs are installed on the carrier. The magnetic rail is set on the ground, and flux from the magnetic rail is pinned by HTSCs. To increase levitation force, repulsive force of the permanent magnet is used. The hybrid levitation system is composed. The permanent magnet is installed under the load stage of the carrier. Repulsive force by the permanent magnet between the load stage on the carrier and the magnetic rail on the ground is used to support the load weight. Levitation and guidance one by pinning effect of the YBaCuO HTSC in the carrier is used to levitate the carrier body. The load stage is separated from the carrier flame and can move freely for vertical direction levitation. For the propulsion system, electromagnet is installed on the surface of the magnetic rail. In this paper, control method of running velocity of the carrier is studied. Propulsion force is given as follows; Air core copper coils are installed on the magnetic rail. Interaction between current of these coils and permanent magnets on the carrier generates propulsion force. Running velocity is controlled by current of the propulsion coils. It is also changed by position of the carrier and the load weight. From the results, stability of the propulsion system is given, and propulsion characteristics are improved.

  17. Novel constant linear velocity control method for the multilevel run-length limited read-only disc

    Science.gov (United States)

    Yan, Mingming; Pei, Jing; Pan, Longfa; Wang, Hequn

    2009-08-01

    A novel constant linear velocity (CLV) control method employing sync pattern detection has been developed for the multi-level run-length limited read-only disc. In the proposed method, the sync pattern is special designed and inserted in the RF signal to detect the velocity error of the spindle. The differentiation method is adopted to detect the sync pattern from the RF signal and is more easy and accurate than using the threshold level slicer. By using the proposed CLV method, the spindle works robust in the CLV mode and the velocity error of the spindle can be suppressed less than 0.3%. The experimental result shows the novel CLV control method for the ML-RLL read-only disc is practicability.

  18. Forecasting to velocities harness racing on average, long, superlong distances (marathon run

    Directory of Open Access Journals (Sweden)

    Klochko L.I.

    2010-05-01

    Full Text Available The prospects of increase of sporting results are shown in a marathon. The sportsmen of high qualification are investigational in age from 17 to 27 years. Sportsmen are practice mainly on distance of 1500m. The degree of deoxygenation during at run with different speed and his attitude is certain toward a maximal deoxygenation. The degree of including of anaerobic metabolism is during work of different power. The indexes of aerobic and anaerobic metabolism allow to forecast sporting results in at run.

  19. Favorable effect of aerobic exercise on arterial pressure and aortic pulse wave velocity during stress testing.

    Science.gov (United States)

    Milatz, Florian; Ketelhut, Sascha; Ketelhut, Sascha; Ketelhut, Reinhard G

    2015-07-01

    Increased central pulse wave velocity is a major risk factor for cardiovascular disease. The favorable influence of exercise on arterial stiffness (AS) and blood pressure (BP) has been reported exclusively at rest. The present study investigated the influence of a single bout of acute cycling on AS and BP during recovery and, moreover, during cold pressor stress testing. 32 healthy men (33.7 ± 8 years, BMI 24 ± 2.5 kg/m²) performed a 60 minute endurance exercise on a bicycle ergometer (45 % VO2max). Before and after exercise aortic pulse wave velocity (aPWV) as well as central and peripheral BP were measured non-invasively at rest and at the end of a 2 minute cold pressor test (CPT). Even after 60 minutes of recovery aPWV (- 0.22 ± 0.3 m / sec) was significantly reduced (p testing.

  20. High prevalence of false-positive plateau phenomena during VO2max testing in adolescents.

    Science.gov (United States)

    Beltrami, Fernando G; Wong, Del P; Noakes, Timothy D

    2014-09-01

    It is believed that a plateau in oxygen consumption (VO2) at the end of an incremental exercise test identifies the upper limits of cardiovascular capacity. We investigated how different criteria influence the frequency with which the "plateau phenomenon" is detected and the prevalence at which "false" plateau phenomena occurs during sub-maximal exercise. Cross-sectional. Six different criteria with 3 different sampling intervals each were used to identify the "plateau phenomenon" from a single data set comprising 63 incremental exercise tests along with secondary criteria based on target heart rate (HR) and respiratory exchange ratio (RER). A single criterion from the original 18 (HALF) was also used to detect the incidence of any plateau phenomena during each test. The plateau phenomenon was detected in 16-82% of the tests depending on the criteria used, mostly as a result of the different sampling intervals. HALF identified 103 "plateau phenomena" but 73 (70.9%) of these occurred during sub-maximal exercise and so were "false". "False" plateaus were verified by at least one secondary criterion in 27% of cases. Participants reached the HR and RER targets after 83.6 ± 11.7% and 81.9 ± 18.1% of total test duration, respectively. The wide range in the percentage of plateau phenomena detected by different criteria plus the high rate (71%) of "false" plateau during sub-maximal exercise could indicate that this phenomenon is a calculation artifact rather than an indicator of true physiological events. Secondary criteria can be reached early in exercise and often identify "false" plateau phenomena as "true". Copyright © 2013 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  1. Associations between VO2max and vitality in older workers: A cross-sectional study

    NARCIS (Netherlands)

    Strijk, J.E.; Proper, K.I.; Klaver, L.; Beek, A.J. van der; Mechelen, W. van

    2010-01-01

    Background. To prevent early exit from work, it is important to study which factors contribute to healthy ageing. One concept that is assumed to be closely related to, and therefore may influence healthy ageing, is vitality. Vitality consists of both a mental and a physical component, and is charact

  2. A Device and Methodology for Measuring Repetitive Lifting VO2max (Oxygen Consumption Rate)

    Science.gov (United States)

    1987-08-01

    and its estimate from skinfold thicknesses ; measurements on 481 men and women aged from 16 to 72 years. Br J Nutr 32:77-92. 3. Intaranont K, Ayoub MM...Justificaton --. By ......... AvaI~bty Co’der, L Ust Avdi iUl I r /1- Table of Contents Table of Contents iii List of Figures iv List of Tables v...during 28 repetitive lifting exercise iv List of Tables 1. Repetitive lifting device specifications 15 2. Subject sample descriptive data 24 3

  3. Four weeks of running sprint interval training improves cardiorespiratory fitness in young and middle-aged adults.

    Science.gov (United States)

    Willoughby, Taura N; Thomas, Matthew P L; Schmale, Matthew S; Copeland, Jennifer L; Hazell, Tom J

    2016-01-01

    The purpose of this study was to determine the effectiveness of a 4-week running sprint interval training protocol to improve both aerobic and anaerobic fitness in middle-aged adults (40-50 years) as well as compare the adaptations to younger adults (20-30 years). Twenty-eight inactive participants - 14 young 20-30-year-olds (n = 7 males) and 14 middle-aged 40-50-year-olds (n = 5 males) - completed 4 weeks of running sprint interval training (4 to 6, 30-s "all-out" sprints on a curved, self-propelled treadmill separated by 4 min active recovery performed 3 times per week). Before and after training, all participants were assessed for maximal oxygen consumption (VO2max), 2000 m time trial performance, and anaerobic performance on a single 30-s sprint. There were no interactions between group and time for any tested variable, although training improved relative VO2max (young = 3.9, middle-aged = 5.2%; P sprint speed (young = 9.3, middle-aged = 2.2%; P sprint speed (young = 6.8, middle-aged = 11.6%; P sprint test. The current study demonstrates that a 4-week running sprint interval training programme is equally effective at improving aerobic and anaerobic fitness in younger and middle-aged adults.

  4. Does Step Length Adjustment Determine Take-Off Accuracy and Approach Run Velocity in Long and Triple Jumps?

    Directory of Open Access Journals (Sweden)

    Hubert Makaruk

    2015-09-01

    Full Text Available Purpose. While take-off accuracy and approach run velocity are known determinants of long and triple jump performance, the interaction of these factors with step length adjustment (SLA is not as clear. Methods. The study involved 39 male and 31 female national-level long and triple jumpers. The Optojump Next device was used to analyse jump attempts. Three groups were identified according to maximum variability of footfall placement (HVF - high, MVF - medium, LVF - Low as well as three groups regarding the onset of step length adjustment (ESLA - early, MSLA - mid, LSLA - late. Results. Take-off accuracy in the LVF and MVF groups was greater compared with the HVF group among females. Among males, the LVF group made significantly (p < 0.05 fewer foul attempts than the HVF group. The ESLA group achieved significantly (p < 0.05 higher velocity during the last five steps of the approach run than the LSLA group in men. Conclusions. Coaches should implement exercises targeting SLA in long and triple jump training exercises to improve performance.

  5. Study on control method of running velocity for the permanent magnet-HTSC hybrid magnetically levitated conveyance system

    Science.gov (United States)

    Nishio, R.; Ikeda, M.; Sasaki, R.; Ohashi, S.

    2011-11-01

    We have developed the magnetically levitated carrying system. In this system, pinning force of high temperature bulk super conductor (HTSC) is used for the levitation and guidance. Four HTSCs are installed on the carrier. The magnetic rail is set on the ground, and flux from the magnetic rail is pinned by HTSCs. To increase levitation force, repulsive force of the permanent magnet is used. The hybrid levitation system is composed. The permanent magnet is installed under the load stage of the carrier. Repulsive force by the permanent magnet between the load stage on the carrier and the magnetic rail on the ground is used to support the load weight. Levitation and guidance one by pinning effect of the YBaCuO HTSC in the carrier is used to levitate the carrier body. The load stage is separated from the carrier flame and can move freely for vertical direction levitation. For the propulsion system, electromagnet is installed on the surface of the magnetic rail. In this paper, control method of running velocity of the carrier is studied. Propulsion force is given as follows; Air core copper coils are installed on the magnetic rail. Interaction between current of these coils and permanent magnets on the carrier generates propulsion force. Running velocity is controlled by current of the propulsion coils. It is also changed by position of the carrier and the load weight. From the results, stability of the propulsion system is given, and propulsion characteristics are improved.

  6. New Zealand Blackcurrant Extract Improves High-Intensity Intermittent Running.

    Science.gov (United States)

    Perkins, Ian Craig; Vine, Sarah Anne; Blacker, Sam David; Willems, Mark Elisabeth Theodorus

    2015-10-01

    We examined the effect of New Zealand blackcurrant (NZBC) extract on high-intensity intermittent running and postrunning lactate responses. Thirteen active males (age: 25 ± 4 yrs, height: 1.82 ± 0.07 m, body mass: 81 ± 14 kg, VO2max: 56 ± 4 ml·kg-1·min-1, vVO2max: 17.6 ± 0.8 km·h-1) performed a treadmill running protocol to exhaustion, which consisted of stages with 6 × 19 s of sprints with 15 s of low-intensity running between sprints. Interstage rest time was 1 min and stages were repeated with increasing sprint speeds. Subjects consumed capsuled NZBC extract (300 mg·day-1 CurraNZ; containing 105 mg anthocyanin) or placebo for 7 days (double-blind, randomized, crossover design, wash-out at least 14 days). Blood lactate was collected for 30 min postexhaustion. NZBC increased total running distance by 10.6% (NZBC: 4282 ± 833 m, placebo: 3871 ± 622 m, p = .02), with the distance during sprints increased by 10.8% (p = .02). Heart rate, oxygen uptake, lactate and rating of perceived exertion were not different between conditions for the first 4 stages completed by all subjects. At exhaustion, blood lactate tended to be higher for NZBC (NZBC: 6.01 ± 1.07 mmol·L-1, placebo: 5.22 ± 1.52 mmol·L-1, p = .07). There was a trend for larger changes in lactate following 15 min (NZBC: -2.89 ± 0.51 mmol·L-1, placebo: -2.46 ± 0.39 mmol·L-1, p = .07) of passive recovery. New Zealand blackcurrant extract (CurraNZ) may enhance performance in sports characterized by high-intensity intermittent exercise as greater distances were covered with repeated sprints, there was higher lactate at exhaustion, and larger changes in lactate during early recovery after repeated sprints to exhaustion.

  7. Critical velocity: a predictor of 2000-m rowing ergometer performance in NCAA D1 female collegiate rowers.

    Science.gov (United States)

    Kendall, Kristina L; Smith, Abbie E; Fukuda, David H; Dwyer, Teddi R; Stout, Jeffrey R

    2011-06-01

    The aims of this study were to examine the use of the critical velocity test as a means of predicting 2000-m rowing ergometer performance in female collegiate rowers, and to study the relationship of selected physiological variables on performance times. Thirty-five female collegiate rowers (mean ± s: age 19.3 ± 1.3 years; height 1.70 ± 0.06 m; weight 69.5 ± 7.2 kg) volunteered to participate in the study. Rowers were divided into two categories based on rowing experience: varsity (more than 1 year collegiate experience) and novice (less than 1 year collegiate experience). All rowers performed two continuous graded maximal oxygen consumption tests (familiarization and baseline) to establish maximal oxygen uptake (VO(2max)), peak power output, and power output at ventilatory threshold. Rowers then completed a critical velocity test, consisting of four time-trials at various distances (400 m, 600 m, 800 m, and 1000 m) on two separate days, with 15 min rest between trials. Following the critical velocity test, rowers completed a 2000-m time-trial. Absolute VO(2max) was the strongest predictor of 2000-m performance (r = 0.923) in varsity rowers, with significant correlations also observed for peak power output and critical velocity (r = 0.866 and r = 0.856, respectively). In contrast, critical velocity was the strongest predictor of 2000-m performance in novice rowers (r = 0.733), explaining 54% of the variability in performance. These findings suggest the critical velocity test may be more appropriate for evaluating performance in novice rowers.

  8. Effect of speed endurance and strength training on performance, running economy and muscular adaptations in endurance-trained runners

    DEFF Research Database (Denmark)

    Vorup Petersen, Jacob; Tybirk Nielsen, Jonas; Gunnarsson, Thomas Petursson;

    2016-01-01

    period. Maximal aerobic speed was 0.6 km h(-1) higher (P ...PURPOSE: To investigate the effects of combined strength and speed endurance (SE) training along with a reduced training volume on performance, running economy and muscular adaptations in endurance-trained runners. METHODS: Sixteen male endurance runners (VO2-max: ~60 ml kg(-1) min(-1)) were...... randomly assigned to either a combined strength and SE training (CSS; n = 9) or a control (CON; n = 7) group. For 8 weeks, CSS replaced their normal moderate-intensity training (~63 km week(-1)) with SE (2 × week(-1)) and strength training (2 × week(-1)) as well as aerobic high (1 × week(-1)) and moderate...

  9. Velocity dispersions in a cluster of stars: How fast could Usain Bolt have run?

    CERN Document Server

    Eriksen, H K; Langangen, O; Wehus, I K

    2008-01-01

    Since that very memorable day at the Beijing 2008 Olympics, a big question on every sports commentator's mind has been "What would the 100 meter dash world record have been, had Usain Bolt not celebrated at the end of his race?" Glen Mills, Bolt's coach suggested at a recent press conference that the time could have been 9.52 seconds or better. We revisit this question by measuring Bolt's position as a function of time using footage of the run, and then extrapolate into the last two seconds based on two different assumptions. First, we conservatively assume that Bolt could have maintained Richard Thompson's, the runner-up, acceleration during the end of the race. Second, based on the race development prior to the celebration, we assume that he could also have kept an acceleration of 0.5 m/s^2 higher than Thompson. In these two cases, we find that the new world record would have been 9.61 +/- 0.04 and 9.55 +/- 0.04 seconds, respectively, where the uncertainties denote 95% statistical errors.

  10. Effects of unaccustomed downhill running on muscle damage, oxidative stress, and leukocyte apoptosis.

    Science.gov (United States)

    Park, Kyung-Shin; Lee, Man-Gyoon

    2015-06-01

    The purpose of this study was to investigate the effect of unaccustomed downhill running on muscle damage, oxidative stress, and leukocyte apoptosis. Thirteen moderately trained male subjects performed three 40 min treadmill runs at ~70% VO2max on separate days: a level run (L) followed by two downhill runs (DH1 and DH2). Blood samples were taken at rest (PRE) and immediately (POST), 2 h, 24 h, and 48 h after each run. Data were analyzed using 2-way repeated measures ANOVA with post hoc Tukey tests. Creatine kinase (CK) activity and oxidative stress level were significantly elevated at 24 h and 48 h following DH1 (P < 0.05). The level of oxidative stress at the POST measurement following DH1 and DH2 was greater than PRE. The rate of leukocyte apoptosis was significantly increased at the POST measurement following all three runs, and remained elevated for up to 48 h following DH1 (P < 0.01). CK activity and oxidative stress were elevated following an acute bout of moderate intensity downhill running, resulting in a greater apoptotic response at 24 h and 48 h post-exercise in comparison with level grade running or a second downhill run. These elevations were blunted following DH2. Although the link between exercise-induced muscle damage and leukocyte apoptosis is currently unknown, the differential response to DH1 vs. L and DH2 indicates that it may be mediated by the elevation of oxidative stress.

  11. Relationship between aerobic fitness and repeated sprint ability in soccer: protocol effect. DOI: 10.5007/1980-0037.2011v13n2p111

    Directory of Open Access Journals (Sweden)

    Leandro Teixeira Floriano

    2011-03-01

    Full Text Available The aim of this study was to evaluate the association between physiological variables related to physical fitness determined by continuous straight running on a treadmill (peak velocity on treadmill: PVTRE, maximum oxygen uptake: VO2max, minimum velocity needed to reach VO2max: vVO2max, and velocity at the anaerobic threshold: vAT and intermittent running with directional changes (peak velocity: PV and repeated sprint ability (RSA in soccer players. Twenty-nine athletes (17.9 ± 1.0 years, 178.7 ± 5.2 cm, 73.6 ± 6.7 kg, and 11.1 ± 1.3% body fat performed the following tests on different days: 1 incremental protocol on a treadmill to determine PVTRE, VO2max, vVO2max, and vAT; 2 incremental intermittent running test to determine PV, and 3 Bangsbo test to evaluate RSA and to determine the mean time (MT, fastest time (FT, and fatigue index (FI. Pearson’s correlation coefficient was used and a level of significance of 5% was adopted. PV obtained in the intermittent running test showed a higher correlation with MT and FT of the RSA test (r = -0.70, p 0.05 and PVTRE (r = -0.42, p 0.05 determined by straight running on a treadmill. In conclusion, the relationship between physical fitness and RSA depends on the type of protocol (continuous line running vs. intermittent with directional changes and the aerobic index used (capacity vs. power.

  12. Haemodynamic effect of metaboreflex activation in men after running above and below the velocity of the anaerobic threshold.

    Science.gov (United States)

    Crisafulli, Antonio; Milia, Raffaele; Lobina, Andrea; Caddeo, Manuela; Tocco, Filippo; Concu, Alberto; Melis, Franco

    2008-04-01

    Previous studies have shown that the muscle metaboreflex, along with its effect on peripheral vasculature, is capable of inducing substantial enhancement in cardiac performance, stroke volume and cardiac output. This study was designed to determine whether the metaboreflex recruited by means of postexercise muscle ischaemia (PEMI) after running at two intensities was capable of eliciting similar enhancement in these cardiovascular parameters. In eight healthy male athletes the metaboreflex was studied with the PEMI method at the start of recovery from running bouts at a velocity of 30% above (PEMI-AV(AT)) or below (PEMI-BV(AT)) the anaerobic threshold previously assessed. Control exercise recovery tests at the same intensities were also conducted. Haemodynamics were evaluated by means of impedance cardiography. The main results were that: (1) the PEMI-AV(AT) test induced an increase in stroke volume, which was not present during the other protocol conditions; (2) the PEMI-AV(AT) test also induced a blunted heart rate response compared with the control situation, but this relative bradycardia was fully compensated by the stroke volume increment so that cardiac output was maintained and even increased in comparison with the other protocol sessions; and (3) finally, there was no detectable increase in systemic vascular resistance during PEMI-AV(AT). These results provide evidence that, like what has previously been reported for small muscle mass exercise, metaboreflex activation after running is capable of enhancing cardiac performance and stroke volume. Moreover, this study strengthens the concept that the cardiovascular response to metaboreflex is not merely the consequence of an increase in systemic vascular resistance.

  13. Influence of Post-Exercise Carbohydrate-Protein Ingestion on Muscle Glycogen Metabolism in Recovery and Subsequent Running Exercise.

    Science.gov (United States)

    Alghannam, Abdullah F; Jedrzejewski, Dawid; Bilzon, James; Thompson, Dylan; Tsintzas, Kostas; Betts, James A

    2016-12-01

    We examined whether carbohydrate-protein ingestion influences muscle glycogen metabolism during short-term recovery from exhaustive treadmill running and subsequent exercise. Six endurance-trained individuals underwent two trials in a randomized double-blind design, each involving an initial run-to-exhaustion at 70% VO2max (Run-1) followed by 4-h recovery (REC) and subsequent run-to-exhaustion at 70% VO2max (Run-2). Carbohydrate-protein (CHO-P; 0.8 g carbohydrate·kg body mass [BM(-1)]·h(-1) plus 0.4 g protein·kg BM(-1)·h(-1)) or isocaloric carbohydrate (CHO; 1.2 g carbohydrate·kg BM(-1)·h(-1)) beverages were ingested at 30-min intervals during recovery. Muscle biopsies were taken upon cessation of Run-1, postrecovery and fatigue in Run-2. Time-to-exhaustion in Run-1 was similar with CHO and CHO-P (81 ± 17 and 84 ± 19 min, respectively). Muscle glycogen concentrations were similar between treatments after Run-1 (99 ± 3 mmol·kg dry mass [dm(-1)]). During REC, muscle glycogen concentrations increased to 252 ± 45 mmol·kg dm(-1) in CHO and 266 ± 30 mmol·kg dm(-1) in CHO-P (p = .44). Muscle glycogen degradation during Run-2 was similar between trials (3.3 ± 1.4 versus 3.5 ± 1.9 mmol·kg dm(-1)·min(-1) in CHO and CHO-P, respectively) and no differences were observed at the respective points of exhaustion (93 ± 21 versus 100 ± 11 mmol·kg dm(-1); CHO and CHO-P, respectively). Similarly, time-to-exhaustion was not different between treatments in Run-2 (51 ± 13 and 49 ± 15 min in CHO and CHO-P, respectively). Carbohydrate-protein ingestion equally accelerates muscle glycogen resynthesis during short-term recovery from exhaustive running as when 1.2 g carbohydrate·kg BM(-1)·h(-1) are ingested. The addition of protein did not alter muscle glycogen utilization or time to fatigue during repeated exhaustive running.

  14. COMPARISON OF LIVE HIGH: TRAIN LOW ALTITUDE AND INTERMITTENT HYPOXIC EXPOSURE

    Directory of Open Access Journals (Sweden)

    Clare E. Humberstone-Gough

    2013-09-01

    Full Text Available Live High:Train Low (LHTL altitude training is a popular ergogenic aid amongst athletes. An alternative hypoxia protocol, acute (60-90 min daily Intermittent Hypoxic Exposure (IHE, has shown potential for improving athletic performance. The aim of this study was to compare directly the effects of LHTL and IHE on the running and blood characteristics of elite triathletes. Changes in total haemoglobin mass (Hbmass, maximal oxygen consumption (VO2max, velocity at VO2max (vVO2max, time to exhaustion (TTE, running economy, maximal blood lactate concentration ([La] and 3 mM [La] running speed were compared following 17 days of LHTL (240 h of hypoxia, IHE (10.2 h of hypoxia or Placebo treatment in 24 Australian National Team triathletes (7 female, 17 male. There was a clear 3.2 ± 4.8% (mean ± 90% confidence limits increase in Hbmass following LHTL compared with Placebo, whereas the corresponding change of -1.4 ± 4.5% in IHE was unclear. Following LHTL, running economy was 2.8 ± 4.4% improved compared to IHE and 3mM [La] running speed was 4.4 ± 4.5% improved compared to Placebo. After IHE, there were no beneficial changes in running economy or 3mM [La] running speed compared to Placebo. There were no clear changes in VO2max, vVO2max and TTE following either method of hypoxia. The clear difference in Hbmass response between LHTL and IHE indicated that the dose of hypoxia in IHE was insufficient to induce accelerated erythropoiesis. Improved running economy and 3mM [La] running speed following LHTL suggested that this method of hypoxic exposure may enhance performance at submaximal running speeds. Overall, there was no evidence to support the use of IHE in elite triathletes

  15. Three Consecutive Days of Interval Runs to Exhaustion Affects Lymphocyte Subset Apoptosis and Migration

    Directory of Open Access Journals (Sweden)

    James W. Navalta

    2014-01-01

    Full Text Available This investigation assessed the lymphocyte subset response to three days of intermittent run exercise to exhaustion. Twelve healthy college-aged males (n=8 and females (n=4 (age = 26 ± 4 years; height = 170.2 ± 10 cm; body mass = 75 ± 18 kg completed an exertion test (maximal running speed and VO2max and later performed three consecutive days of an intermittent run protocol to exhaustion (30 sec at maximal running speed and 30 sec at half of the maximal running speed. Blood was collected before exercise (PRE and immediately following the treadmill bout (POST each day. When the absolute change from baseline was evaluated (i. e., Δ baseline, a significant change in CD4+ and CD8+ for CX3CR1 cells was observed by completion of the third day. Significant changes in both apoptosis and migration were observed following two consecutive days in CD19+ lymphocytes, and the influence of apoptosis persisted following the third day. Given these lymphocyte responses, it is recommended that a rest day be incorporated following two consecutive days of a high-intensity intermittent run program to minimize immune cell modulations and reduce potential susceptibility.

  16. Stabilization of gaze during circular locomotion in darkness. II. Contribution of velocity storage to compensatory eye and head nystagmus in the running monkey

    Science.gov (United States)

    Solomon, D.; Cohen, B.

    1992-01-01

    1. Yaw eye in head (Eh) and head on body velocities (Hb) were measured in two monkeys that ran around the perimeter of a circular platform in darkness. The platform was stationary or could be counterrotated to reduce body velocity in space (Bs) while increasing gait velocity on the platform (Bp). The animals were also rotated while seated in a primate chair at eccentric locations to provide linear and angular accelerations similar to those experienced while running. 2. Both animals had head and eye nystagmus while running in darkness during which slow phase gaze velocity on the body (Gb) partially compensated for body velocity in space (Bs). The eyes, driven by the vestibuloocular reflex (VOR), supplied high-frequency characteristics, bringing Gb up to compensatory levels at the beginning and end of the slow phases. The head provided substantial gaze compensation during the slow phases, probably through the vestibulocollic reflex (VCR). Synchronous eye and head quick phases moved gaze in the direction of running. Head movements occurred consistently only when animals were running. This indicates that active body and limb motion may be essential for inducing the head-eye gaze synergy. 3. Gaze compensation was good when running in both directions in one animal and in one direction in the other animal. The animals had long VOR time constants in these directions. The VOR time constant was short to one side in one animal, and it had poor gaze compensation in this direction. Postlocomotory nystagmus was weaker after running in directions with a long VOR time constant than when the animals were passively rotated in darkness. We infer that velocity storage in the vestibular system had been activated to produce continuous Eh and Hb during running and to counteract postrotatory afterresponses. 4. Continuous compensatory gaze nystagmus was not produced by passive eccentric rotation with the head stabilized or free. This indicates that an aspect of active locomotion, most

  17. Pre-exercise stretching does not impact upon running economy.

    Science.gov (United States)

    Hayes, Philip R; Walker, Adrian

    2007-11-01

    Pre-exercise stretching has been widely reported to reduce performance in tasks requiring maximal or near-maximal force or torque. The purpose of this study was to compare the effects of 3 different pre-exercise stretching routines on running economy. Seven competitive male middle and long-distance runners (mean +/- SD) age: 32.5 +/- 7.7 years; height: 175.0 +/- 8.8 cm; mass: 67.8 +/- 8.6 kg; V(.-)O2max: 66.8 +/- 7.0 ml x kg(-1) x min(-1)) volunteered to participate in this study. Each participant completed 4 different pre-exercise conditions: (a) a control condition, (b) static stretching, (c) progressive static stretching, and (d) dynamic stretching. Each stretching routine consisted of 2 x 30-second stretches for each of 5 exercises. Dependent variables measured were sit and reach test before and after each pre-exercise routine, running economy (ml x kg(-1) x km(-1)), and steady-state oxygen uptake (ml x kg(-1) x min(-1)), which were measured during the final 3 minutes of a 10-minute run below lactate threshold. All 3 stretching routines resulted in an increase in the range of movement (p = 0.008). There was no change in either running economy (p = 0.915) or steady-state V(.-)O2 (p = 0.943). The lack of change in running economy was most likely because it was assessed after a period of submaximal running, which may have masked any effects from the stretching protocols. Previously reported reductions in performance have been attributed to reduced motor unit activation, presumably IIX. In this study, these motor units were likely not to have been recruited; this may explain the unimpaired performance. This study suggests that pre-exercise stretching has no impact upon running economy or submaximal exercise oxygen cost.

  18. Effects of an Elastic Hamstring Assistance Device During Downhill Running

    Directory of Open Access Journals (Sweden)

    Aldret Randy L

    2017-06-01

    Full Text Available The purpose of this study was to determine the appropriateness of using an elastic hamstring assistance device to reduce perceived levels of soreness, increase isometric strength, increase passive range of motion, and decrease biomarkers of muscle damage after eccentric exercise, specifically, downhill running This study was conducted in a university exercise physiology laboratory placing sixteen apparently healthy males (X = 21.6 ± 2.5 years into two groups using a pre-test/post-test design. Pre-intervention measures taken included participants’ body height, body mass, body fat, capillary blood samples, VO2max, isometric hamstring strength at 45 and 90 degrees of flexion and passive hamstring range of motion. Post-intervention measures included blood biomarkers, passive range of motion, the perceived level of soreness and isometric strength. An analysis of normality of data was initially conducted followed by multivariate analysis of variance (MANOVA of hamstring strength at 45 and 90 degrees of flexion, blood myoglobin and passive range of motion of the hamstrings. Statistically significant changes were noted in subject-perceived muscle soreness and isometric strength at 90 degrees at the 24-hour post-exercise trial measure between the two groups. Results would suggest the findings could be explained by the decrease in muscle soreness from utilizing the device during the exercise trial. Further research should be conducted to address sample size issues and to determine if the results are comparable on different surfaces.

  19. Effects of an Elastic Hamstring Assistance Device During Downhill Running.

    Science.gov (United States)

    Aldret, Randy L; Trahan, Brittany A; Davis, Greggory; Campbell, Brian; Bellar, David M

    2017-06-01

    The purpose of this study was to determine the appropriateness of using an elastic hamstring assistance device to reduce perceived levels of soreness, increase isometric strength, increase passive range of motion, and decrease biomarkers of muscle damage after eccentric exercise, specifically, downhill running This study was conducted in a university exercise physiology laboratory placing sixteen apparently healthy males (X = 21.6 ± 2.5 years) into two groups using a pre-test/post-test design. Pre-intervention measures taken included participants' body height, body mass, body fat, capillary blood samples, VO2max, isometric hamstring strength at 45 and 90 degrees of flexion and passive hamstring range of motion. Post-intervention measures included blood biomarkers, passive range of motion, the perceived level of soreness and isometric strength. An analysis of normality of data was initially conducted followed by multivariate analysis of variance (MANOVA) of hamstring strength at 45 and 90 degrees of flexion, blood myoglobin and passive range of motion of the hamstrings. Statistically significant changes were noted in subject-perceived muscle soreness and isometric strength at 90 degrees at the 24-hour post-exercise trial measure between the two groups. Results would suggest the findings could be explained by the decrease in muscle soreness from utilizing the device during the exercise trial. Further research should be conducted to address sample size issues and to determine if the results are comparable on different surfaces.

  20. CARDIORESPIRATORY RESPONSES TO STATIONARY RUNNING IN WATER AND ON LAND

    Directory of Open Access Journals (Sweden)

    uiz Fernando M. Kruel

    2013-09-01

    Full Text Available The aim of the study was to compare maximal and submaximal cardiorespiratory responses between progressive tests on a treadmill on land (TRE, and stationary running on land (SRL and in water (SRW, while also comparing two methods of determining the second turn point (ST (ventilatory curve and heart rate deflection point. The study sample consisted of nine active women (23 ± 1.94 years that performed three maximal protocols in separate days. Heart rate (HR and oxygen uptake (VO2 were measured in all sessions. The data were analyzed using repeated-measures ANOVA and two-way repeated measures ANOVA with post-hoc Bonferroni test. Greater values of maximal HR (HRmax and HR at ST (HRST were observed during exercise performed on TRE and during the SRL, compared to the SRW (p < 0.05. The results for maximal VO2 (VO2max and VO2 at ST (VO2ST showed greater and significant values on TRE compared to STL and STW (p < 0.05. Furthermore, the HR and VO2 corresponding to the ST showed similar values between the two methods. Thus, the main conclusion of the present study was that the HR deflection point seems to be a simple and practical alternative method for determining the ST in all protocols analyzed

  1. The Expression of MMP-2 Following Immobilization and High-Intensity Running in Plantaris Muscle Fiber in Rats

    Directory of Open Access Journals (Sweden)

    Eli Carmeli

    2006-01-01

    Full Text Available The effect of 2-week, high-intensity running and a 2-week immobilization on muscle fiber type composition of the plantaris muscle from 18 female, 6-month-old Wistar rats (running, n = 6; immobilization, n = 6; sedentary control, n = 6 was bio- and histochemically investigated. The high-intensity treadmill running began with 20 min (32 m/min, 0% gradient, 75% VO2 max, up to 50 min/day. Right hind limbs were immobilized by an external fixation procedure for 13 days. Muscle mass of the plantaris muscle in the immobilized groups was reduced by 16% in comparison with the sedentary control group. High-intensity running and immobilization increased both mRNA and protein levels of matrix metalloproteinase type 2 (MMP-2 in plantaris. Running and immobilization decreased the percentages of transverse sectional area of fast-twitch glycolytic (FG type IIb fibers, running increased relative cross-sectional area of fast-twitch oxidative glycolytic (FOG type IIa muscle fibers, whereas immobilization increased relative cross-sectional area of slow-twitch oxidative (SO muscle fibers (type I. Our results suggest that both high-intensity running and immobilization are enough to induce overwhelming changes in plantaris.

  2. Reflex response and control of the human soleus and gastrocnemius muscles during walking and running at increasing velocity

    DEFF Research Database (Denmark)

    Simonsen, Erik B; Alkjær, Tine; Raffalt, Peter C

    2012-01-01

    than the soleus H-reflex. In both muscles the H-reflex increased significantly from walking to running but also with increasing running speed. The peak of EMG activity increased in both muscles with increasing speed. The V-wave of both muscles was absent or rather low during walking, but it increased...... significantly from walking to running with increasing running speed in the soleus but not in the medial gastrocnemius. In both muscles the V-wave was highest just prior to heel strike. It is suggested that this was due to a high firing frequency of the motoneurones in this phase of the movement. It is concluded...

  3. High chronic training loads and exposure to bouts of maximal velocity running reduce injury risk in elite Gaelic football.

    Science.gov (United States)

    Malone, Shane; Roe, Mark; Doran, Dominic A; Gabbett, Tim J; Collins, Kieran

    2017-03-01

    To examine the relationship between chronic training loads, number of exposures to maximal velocity, the distance covered at maximal velocity, percentage of maximal velocity in training and match-play and subsequent injury risk in elite Gaelic footballers. Prospective cohort design. Thirty-seven elite Gaelic footballers from one elite squad were involved in a one-season study. Training and game loads (session-RPE multiplied by duration in min) were recorded in conjunction with external match and training loads (using global positioning system technology) to measure the distance covered at maximal velocity, relative maximal velocity and the number of player exposures to maximal velocity across weekly periods during the season. Lower limb injuries were also recorded. Training load and GPS data were modelled against injury data using logistic regression. Odds ratios (OR) were calculated based on chronic training load status, relative maximal velocity and number of exposures to maximal velocity with these reported against the lowest reference group for these variables. Players who produced over 95% maximal velocity on at least one occasion within training environments had lower risk of injury compared to the reference group of 85% maximal velocity on at least one occasion (OR: 0.12, p=0.001). Higher chronic training loads (≥4750AU) allowed players to tolerate increased distances (between 90 to 120m) and exposures to maximal velocity (between 10 to 15 exposures), with these exposures having a protective effect compared to lower exposures (OR: 0.22 p=0.026) and distance (OR=0.23, p=0.055). Players who had higher chronic training loads (≥4750AU) tolerated increased distances and exposures to maximal velocity when compared to players exposed to low chronic training loads (≤4750AU). Under- and over-exposure of players to maximal velocity events (represented by a U-shaped curve) increased the risk of injury. Copyright © 2016 Sports Medicine Australia. Published by

  4. No positive influence of ingesting chia seed oil on human running performance.

    Science.gov (United States)

    Nieman, David C; Gillitt, Nicholas D; Meaney, Mary Pat; Dew, Dustin A

    2015-05-15

    Runners (n = 24) reported to the laboratory in an overnight fasted state at 8:00 am on two occasions separated by at least two weeks. After providing a blood sample at 8:00 am, subjects ingested 0.5 liters flavored water alone or 0.5 liters water with 7 kcal kg-1 chia seed oil (random order), provided another blood sample at 8:30 am, and then started running to exhaustion (~70% VO2max). Additional blood samples were collected immediately post- and 1-h post-exercise. Despite elevations in plasma alpha-linolenic acid (ALA) during the chia seed oil (337%) versus water trial (35%) (70.8 ± 8.6, 20.3 ± 1.8 μg mL(-1), respectively, p Chia seed oil supplementation compared to water alone in overnight fasted runners before and during prolonged, intensive running caused an elevation in plasma ALA, but did not enhance run time to exhaustion, alter RER, or counter elevations in cortisol and inflammatory outcome measures.

  5. Influence of Running and Walking on Hormonal Regulators of Appetite in Women

    Directory of Open Access Journals (Sweden)

    D. Enette Larson-Meyer

    2012-01-01

    Full Text Available Nine female runners and ten walkers completed a 60 min moderate-intensity (70% VO2max run or walk, or 60 min rest in counterbalanced order. Plasma concentrations of the orexogenic peptide ghrelin, anorexogenic peptides peptide YY (PYY, glucagon-like peptide-1 (GLP-1, and appetite ratings were measured at 30 min interval for 120 min, followed by a free-choice meal. Both orexogenic and anorexogenic peptides were elevated after running, but no changes were observed after walking. Relative energy intake (adjusted for cost of exercise/rest was negative in the meal following running (−194±206 kcal versus walking (41±196 kcal (P=0.015, although both were suppressed (P<0.05 compared to rest (299±308 and 284±121 kcal, resp.. The average rate of change in PYY and GLP-1 over time predicted appetite in runners, but only the change in GLP-1 predicted hunger (P=0.05 in walkers. Results provide evidence that exercise-induced alterations in appetite are likely driven by complex changes in appetite-regulating hormones rather than change in a single gut peptide.

  6. Economy of running: beyond the measurement of oxygen uptake.

    Science.gov (United States)

    Fletcher, Jared R; Esau, Shane P; Macintosh, Brian R

    2009-12-01

    The purpose of this study was to compare running economy across three submaximal speeds expressed as both oxygen cost (mlxkg(-1)xkm(-1)) and the energy required to cover a given distance (kcalxkg(-1)xkm(-1)) in a group of trained male distance runners. It was hypothesized that expressing running economy in terms of caloric unit cost would be more sensitive to changes in speed than oxygen cost by accounting for differences associated with substrate utilization. Sixteen highly trained male distance runners [maximal oxygen uptake (Vo(2max)) 66.5 +/- 5.6 mlxkg(-1)xmin(-1), body mass 67.9 +/- 7.3 kg, height 177.6 +/- 7.0 cm, age 24.6 +/- 5.0 yr] ran on a motorized treadmill for 5 min with a gradient of 0% at speeds corresponding to 75%, 85%, and 95% of speed at lactate threshold with 5-min rest between stages. Oxygen uptake was measured via open-circuit calorimetry. Average oxygen cost was 221 +/- 19, 217 +/- 15, and 221 +/- 13 mlxkg(-1)xkm(-1), respectively. Caloric unit cost was 1.05 +/- 0.09, 1.07 +/- 0.08, and 1.11 +/- 0.07 kcalxkg(-1)xkm(-1) at the three trial speeds, respectively. There was no difference in oxygen cost with respect to speed (P = 0.657); however, caloric unit cost significantly increased with speed (P < 0.001). It was concluded that expression of running economy in terms of caloric unit cost is more sensitive to changes in speed and is a more valuable expression of running economy than oxygen uptake, even when normalized per distance traveled.

  7. Transferability of running and cycling training zones in triathletes: implications for steady-state exercise.

    Science.gov (United States)

    Carey, Daniel G; Tofte, Courtney; Pliego, German J; Raymond, Robert L

    2009-01-01

    The primary objective of this study was to determine whether physiological measurements obtained from one mode of testing and training could be applied to another mode, as in prescribing heart rate (HR) zone training from cyling to running. Secondary objectives were 1) to assess the validity of applying data from incremental testing to steady-state exercise, and 2) to compare breakpoint in respiratory rate (RR) with the conventional method of anaerobic threshold (AT) breakpoint, the ventilatory equivalent for oxygen VE/VO2). Sixteen experienced triathletes performed VO2max testing on a cycle ergometer (CE) and treadmill (TM). In addition, a 30-minute time trial (TT) was performed on a CE. No significant differences were observed between modes of testing for VO2max (CE = 68.4 +/- 11.1 mlxkgxmin, TM = 69.0 +/- 13.2 mlxkgxmin), maximum HR (CE = 177.1 +/- 6.1 bpm, TM = 178.1 +/- 7.4 bpm), or AT (CE AT HR = 153.9 +/- 10.5 bpm, TM AT HR = 157.0 +/- 9.5 bpm). Although the mean difference in AT HR was small (3.1 bpm), a small correlation coefficient (0.321) between the AT for the 2 testing modes resulted in a large total error (TE = 12.1 bpm), indicating limited practical application of training zones between modes of testing. Mean TT HR and mean TT RR were significantly greater than mean AT HR (159.4 +/- 8.9 vs. 153.9 +/- 10.5 bpm) and mean AT RR (37.8 +/- 6.0 vs. 32.4 +/- 3.2 breaths per minute) because of significant "drift" in these 2 variables over time, whereas TT watts and AT watts were not significantly different (249.1 +/- 47.8 vs. 240.6 +/- 71.1 W). Finally, a significant difference and large TE (9.0 bpm) betweenVE/VO2 AT HR and the RR AT HR (153.9 +/- 10.5 and 158.4 +/- 10.0 bpm) may preclude the practical use of the RR breakpoint. From the results of this study, it is recommended that the triathlete perform sport-specific testing to assess training zones for cycling and running. In addition, because both HR and RR "drift" upward with steady-state exercise, AT

  8. Exercise training does not improve myocardial diastolic tissue velocities in Type 2 diabetes

    Directory of Open Access Journals (Sweden)

    Nenonen Arja

    2007-09-01

    Full Text Available Abstract Background Myocardial diastolic tissue velocities are reduced already in newly onset Type 2 diabetes mellitus (T2D. Poor disease control may lead to left ventricular (LV systolic dysfunction and heart failure. The aim of this study was to assess the effects of exercise training on myocardial diastolic function in T2D patients without ischemic heart disease. Methods 48 men (52.3 ± 5.6 yrs with T2D were randomized to supervised training four times a week and standard therapy (E, or standard treatment alone (C for 12 months. Glycated hemoglobin (HbA1c, oxygen consumption (VO2max, and muscle strength (Sit-up were measured. Tissue Doppler Imaging (TDI was used to determine the average maximal mitral annular early (Ea and late (Aa diastolic as well as systolic (Sa velocities, systolic strain (ε and strain rate (έ from the septum, and an estimation of left ventricular end diastolic pressure (E/Ea. Results Exercise capacity (VO2max, E 32.0 to 34.7 vs. C 32.6 to 31.5 ml/kg/min, p = .001, muscle strength (E 12.7 to 18.3 times vs. C 14.6 to 14.7 times, p 1c (E 8.2 to 7.5% vs. C 8.0 to 8.4%, p = .006 improved significantly in the exercise group compared to the controls (ANOVA. Systolic blood pressure decreased in the E group (E 144 to 138 mmHg vs. C 146 to 144 mmHg, p = .04. Contrary to risk factor changes diastolic long axis relaxation did not improve significantly, early diastolic velocity Ea from 8.1 to 7.9 cm/s for the E group vs. C 7.4 to 7.8 cm/s (p = .85, ANOVA. Likewise, after 12 months the mitral annular systolic velocity, systolic strain and strain rate, as well as E/Ea were unchanged. Conclusion Exercise training improves endurance and muscle fitness in T2D, resulting in better glycemic control and reduced blood pressure. However, myocardial diastolic tissue velocities did not change significantly. Our data suggest that a much longer exercise intervention may be needed in order to reverse diastolic impairment in diabetics, if at all

  9. Physiological and biomechanical responses while running with and without a stroller.

    Science.gov (United States)

    Smith, J D; Smith, J D; Kinser, K B; Dugan, E; Reed, M

    2005-09-01

    This study examined the effects of pushing a jogging stroller on biomechanical and physiological variables. The hypothesis was that running with a stroller for 30 minutes would shorten stride length and increase physiological indices of exercise. this was a repeated measures design. participants were recruited from road races in the Dallas/Fort Worth, TX area. Graded exercise tests were performed in a laboratory setting, field tests were performed on a 400 m all-weather outdoor track. 5 males and 5 females were assessed. participants performed a graded exercise test and 2 field tests. The 1st field test involved running at 75% VO2max for 30 minutes without a stroller and the 2nd involved running at the same speed with the stroller. VO2, stride length, heart rate, lactate, ventilation, and RPE were evaluated. No differences for VO2 or stride length were evident. Heart rate (p=0.0001), lactate concentration (p=0.025), ventilation (p=0.009), and RPE (p=0.002) increased from 10 to 30 minutes while running with the stroller. Heart rate (p=0.002), lactate concentration (p=0.0001), ventilation (p=0.006), and RPE (p=0.001) were significantly higher while running with the stroller after 30 minutes compared to running without it. These results indicate that pushing a stroller affects some indices of exercise intensity while running. Gait does not change. These data do not support an association between stroller use during running and an increase risk of orthopedic injury. Further studies should examine these variables at lower intensities that are run by most recreational joggers.

  10. The effect of carrying a portable respiratory gas analysis system on energy expenditure during incremental running.

    Science.gov (United States)

    Sparks, S Andy; Orme, Duncan; Mc Naughton, Lars R

    2013-05-01

    This study aimed to assess the effect of portable gas analysis system carriage on energy expenditure (EE) during incremental treadmill running. Eight males (Mean ± SD) age 25.0 ± 9.47 y, body mass 78.5 ± 8.39 kg, completed an experimental trial (PT) during which they wore the system in a chest harness and a control trial (CT) when the system was externally supported. Each protocol consisted of 4 min stages at speeds of 0, 4, 7, 10, 12, 14 km h(-1). Increments continued until volitional exhaustion. The EE was greater (3.95 and 7.02% at 7 and 14 km h(-1) respectively) during PT (p gas analysis systems therefore only increase EE when running sub-maximally, but VO(2max) is unaffected, suggesting that using portable gas analysis systems in field-based situations is appropriate for maximal aerobic capacity measurement, but the effects of prolonged use on EE remains unclear. Copyright © 2012 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  11. Effects of cognitive stimulation with a self-modeling video on time to exhaustion while running at maximal aerobic velocity: a pilot study.

    Science.gov (United States)

    Hagin, Vincent; Gonzales, Benoît R; Groslambert, Alain

    2015-04-01

    This study assessed whether video self-modeling improves running performance and influences the rate of perceived exertion and heart rate response. Twelve men (M age=26.8 yr., SD=6; M body mass index=22.1 kg.m(-2), SD=1) performed a time to exhaustion running test at 100 percent maximal aerobic velocity while focusing on a video self-modeling loop to synchronize their stride. Compared to the control condition, there was a significant increase of time to exhaustion. Perceived exertion was lower also, but there was no significant change in mean heart rate. In conclusion, the video self-modeling used as a pacer apparently increased endurance by decreasing perceived exertion without affecting the heart rate.

  12. RUN DMC: An efficient, parallel code for analyzing Radial Velocity Observations using N-body Integrations and Differential Evolution Markov chain Monte Carlo

    CERN Document Server

    Nelson, Benjamin E; Payne, Matthew J

    2013-01-01

    In the 20+ years of Doppler observations of stars, scientists have uncovered a diverse population of extrasolar multi-planet systems. A common technique for characterizing the orbital elements of these planets is Markov chain Monte Carlo (MCMC), using a Keplerian model with random walk proposals and paired with the Metropolis-Hastings algorithm. For approximately a couple of dozen planetary systems with Doppler observations, there are strong planet-planet interactions due to the system being in or near a mean-motion resonance (MMR). An N-body model is often required to accurately describe these systems. Further computational difficulties arise from exploring a high-dimensional parameter space ($\\sim$7 x number of planets) that can have complex parameter correlations. To surmount these challenges, we introduce a differential evolution MCMC (DEMCMC) applied to radial velocity data while incorporating self-consistent N-body integrations. Our Radial velocity Using N-body DEMCMC (RUN DMC) algorithm improves upon t...

  13. Plasma volume expansion does not increase maximal cardiac output or VO2 max in lowlanders acclimatized to altitude

    DEFF Research Database (Denmark)

    Calbet, José A L; Rådegran, Göran; Boushel, Robert Christopher

    2004-01-01

    With altitude acclimatization, blood hemoglobin concentration increases while plasma volume (PV) and maximal cardiac output (Qmax) decrease. This investigation aimed to determine whether reduction of Qmax at altitude is due to low circulating blood volume (BV). Eight Danish lowlanders (3 females, 5...... males: age 24.0 +/- 0.6 yr; mean +/- SE) performed submaximal and maximal exercise on a cycle ergometer after 9 wk at 5,260 m altitude (Mt. Chacaltaya, Bolivia). This was done first with BV resulting from acclimatization (BV = 5.40 +/- 0.39 liters) and again 2-4 days later, 1 h after PV expansion with 1...... level Qmax and exercise capacity were restored with hyperoxia at altitude independently of BV. Low BV is not a primary cause for reduction of Qmax at altitude when acclimatized. Furthermore, hemodilution caused by PV expansion at altitude is compensated for by increased systemic O2 extraction...

  14. Difference in Physiological Components of VO2 Max During Incremental and Constant Exercise Protocols for the Cardiopulmonary Exercise Test.

    Science.gov (United States)

    Yamamoto, Junshiro; Harada, Tetsuya; Okada, Akinori; Maemura, Yuko; Yamamoto, Misaki; Tabira, Kazuyuki

    2014-08-01

    [Purpose] VO2 is expressed as the product of cardiac output and O2 extraction by the Fick equation. During the incremental exercise test and constant high-intensity exercise test, VO2 results in the attainment of maximal O2 uptake at exhaustion. However, the differences in the physiological components, cardiac output and muscle O2 extraction, have not been fully elucidated. We tested the hypothesis that constant exercise would result in higher O2 extraction than incremental exercise at exhaustion. [Subjects] Twenty-five subjects performed incremental exercise and constant exercise at 80% of their peak work rate. [Methods] Ventilatory, cardiovascular, and muscle oxygenation responses were measured using a gas analyzer, Finapres, and near-infrared spectroscopy, respectively. [Results] VO2 was not significantly different between the incremental exercise and constant exercise. However, cardiac output and muscle O2 saturation were significantly lower for the constant exercise than the incremental exercise at the end of exercise. [Conclusion] These findings indicate that if both tests produce a similar VO2 value, the VO2 in incremental exercise would have a higher ratio of cardiac output than constant exercise, and VO2 in constant exercise would have a higher ratio of O2 extraction than incremental exercise at the end of exercise.

  15. Effect of blood haemoglobin concentration on V(O2,max) and cardiovascular function in lowlanders acclimatised to 5260 m

    DEFF Research Database (Denmark)

    Calbet, J A L; Rådegran, G; Boushel, Robert Christopher

    2002-01-01

    +/- 5 to 185 +/- 5 g l(-1) (P delivery was reduced...... and maximal V(O(2)) was thus maintained by higher O(2) extraction. While CO increased linearly with work rate irrespective of [Hb] or inspired oxygen fraction (F(I,O(2))), both LBF and leg vascular conductance were systematically higher when [Hb] was low. Close and significant relationships were seen between...

  16. Plasma volume expansion does not increase maximal cardiac output or VO2 max in lowlanders acclimatized to altitude.

    Science.gov (United States)

    Calbet, José A L; Rådegran, Göran; Boushel, Robert; Søndergaard, Hans; Saltin, Bengt; Wagner, Peter D

    2004-09-01

    With altitude acclimatization, blood hemoglobin concentration increases while plasma volume (PV) and maximal cardiac output (Qmax) decrease. This investigation aimed to determine whether reduction of Qmax at altitude is due to low circulating blood volume (BV). Eight Danish lowlanders (3 females, 5 males: age 24.0 +/- 0.6 yr; mean +/- SE) performed submaximal and maximal exercise on a cycle ergometer after 9 wk at 5,260 m altitude (Mt. Chacaltaya, Bolivia). This was done first with BV resulting from acclimatization (BV = 5.40 +/- 0.39 liters) and again 2-4 days later, 1 h after PV expansion with 1 liter of 6% dextran 70 (BV = 6.32 +/- 0.34 liters). PV expansion had no effect on Qmax, maximal O2 consumption (VO2), and exercise capacity. Despite maximal systemic O2 transport being reduced 19% due to hemodilution after PV expansion, whole body VO2 was maintained by greater systemic O2 extraction (P VO2 during exercise regardless of PV. Pulmonary ventilation, gas exchange, and acid-base balance were essentially unaffected by PV expansion. Sea level Qmax and exercise capacity were restored with hyperoxia at altitude independently of BV. Low BV is not a primary cause for reduction of Qmax at altitude when acclimatized. Furthermore, hemodilution caused by PV expansion at altitude is compensated for by increased systemic O2 extraction with similar peak muscular O2 delivery, such that maximal exercise capacity is unaffected.

  17. Effects of exercise and group counselling on body composition and VO(2max) in overweight women with polycystic ovary syndrome

    DEFF Research Database (Denmark)

    Roessler, Kirsten Kaya; Birkebaek, Camilla; Ravn, Pernille

    2013-01-01

    BACKGROUND: Polycystic ovary syndrome (PCOS) is often associated with an increased waist circumference and with lower cardio-respiratory fitness as a consequence of obesity, which may be improved by physical activity. OBJECTIVE: To investigate the effect of high-intensity aerobic training combined...... with group counselling sessions on anthropometry and cardio-respiratory fitness in women with PCOS. DESIGN: Seventeen sedentary, overweight women with PCOS were randomized in a cross-over design to 16 weeks of intervention: Eight weeks high intensity aerobic exercise was followed by eight weeks group...

  18. Changes in VO2 Max. Resulting from Bicycle Training at Different Intensities Holding Total Mechanical Work Constant.

    Science.gov (United States)

    Burke, Edmund A., Jr.; Franks, B. Don

    Effects of different training intensities on oxygen intake were determined in this study. Sixteen male subjects aged 16-18 were randomly assigned to one of three training groups or a control group. The training groups trained 3 days per week on bicycle ergometers at different intensities (85 percent, 75 percent, or 65 percent of heart rate…

  19. Effects of Obstacles on the Dynamics of Kinesins, Including Velocity and Run Length, Predicted by a Model of Two Dimensional Motion.

    Directory of Open Access Journals (Sweden)

    Woochul Nam

    Full Text Available Kinesins are molecular motors which walk along microtubules by moving their heads to different binding sites. The motion of kinesin is realized by a conformational change in the structure of the kinesin molecule and by a diffusion of one of its two heads. In this study, a novel model is developed to account for the 2D diffusion of kinesin heads to several neighboring binding sites (near the surface of microtubules. To determine the direction of the next step of a kinesin molecule, this model considers the extension in the neck linkers of kinesin and the dynamic behavior of the coiled-coil structure of the kinesin neck. Also, the mechanical interference between kinesins and obstacles anchored on the microtubules is characterized. The model predicts that both the kinesin velocity and run length (i.e., the walking distance before detaching from the microtubule are reduced by static obstacles. The run length is decreased more significantly by static obstacles than the velocity. Moreover, our model is able to predict the motion of kinesin when other (several motors also move along the same microtubule. Furthermore, it suggests that the effect of mechanical interaction/interference between motors is much weaker than the effect of static obstacles. Our newly developed model can be used to address unanswered questions regarding degraded transport caused by the presence of excessive tau proteins on microtubules.

  20. Metabolic responses at various intensities relative to critical swimming velocity.

    Science.gov (United States)

    Toubekis, Argyris G; Tokmakidis, Savvas P

    2013-06-01

    To avoid any improper training load, the speed of endurance training needs to be regularly adjusted. Both the lactate threshold (LT) velocity and the velocity corresponding to the maximum lactate steady state (MLSS) are valid and reliable indices of swimming aerobic endurance and commonly used for evaluation and training pace adjustment. Alternatively, critical velocity (CV), defined as the velocity that can be maintained without exhaustion and assessed from swimming performance of various distances, is a valid, reliable, and practical index of swimming endurance, although the selection of the proper distances is a determinant factor. Critical velocity may be 3-6 and 8-11% faster compared with MLSS and LT, respectively. Interval swimming at CV will probably show steady-lactate concentration when the CV has been calculated by distances of 3- to 15-minute duration, and this is more evident in adult swimmers, whereas increasing or decreasing lactate concentration may appear in young and children swimmers. Therefore, appropriate corrections should be made to use CV for training pace adjustment. Findings in young and national level adult swimmers suggest that repetitions of distances of 100-400 m, and velocities corresponding to a CV range of 98-102% may be used for pacing aerobic training, training at the MLSS, and possibly training for improvement of VO2max. Calculation of CV from distances of 200-400, 50-100-200-400, or 100-800 m is an easy and practical method to assess aerobic endurance. This review intends to study the physiological responses and the feasibility of using CV for aerobic endurance evaluation and training pace adjustment, to help coaches to prescribe training sets for different age-group swimmers.

  1. Effects of prolonged running performed at the intensity corresponding to the onset of blood lactate accumulation, on maximum isokinetic strength in active non-athletic individuals Efeitos da corrida prolongada realizada na intensidade correspondente ao início do acúmulo do lactato no sangue na força máxima isocinética em indivíduos ativos não atletas

    Directory of Open Access Journals (Sweden)

    BS Denadai

    2007-06-01

    Full Text Available OBJECTIVE: The objective of this study was to analyze the effects of prolonged continuous running performed at the intensity corresponding to the onset of blood lactate accumulation (OBLA, on the peak torque of the knee extensors, analyzed in relation to different types of contraction and movement velocities in active individuals. METHOD: Eight men (23.4 ± 2.1 years; 75.8 ± 8.7 kg; 171.1 ± 4.5 cm participated in this study. First, the subjects performed an incremental test until volitional exhaustion to determine the velocity corresponding to OBLA. Then, the subjects returned to the laboratory on two occasions, separated by at least seven days, to perform five maximal isokinetic contractions of the knee extensors at two angular velocities (60 and 180º.s-1 under eccentric and concentric conditions. Eccentric peak torque (EPT and Concentric peak torque (CPT were measured at each velocity. One session was performed after a standardized warm-up period (5 min at 50% VO2max. The other session was performed after continuous running at OBLA until volitional exhaustion. These sessions were conducted in random order. RESULTS: There was a significant reduction in CPT only at 60º.s-1 (259.0 ± 46.4 and 244.0 ± 41.4 N.m. However, the reduction in EPT was significant at 60º.s-1 (337.3 ± 43.2 and 321.7 ± 60.0 N.m and 180º.s-1 (346.1 ± 38.0 and 319.7 ± 43.6 N.m. The relative strength losses after the running exercise were significant different between contraction types only at 180º.s-1. CONCLUSION: We can conclude that, in active individuals, the reduction in peak torque after prolonged continuous running at OBLA may be dependent on the type of contraction and angular velocity.OBJETIVO: O objetivo deste estudo foi analisar os efeitos da corrida contínua prolongada realizada na intensidade correspondente ao início do acúmulo do lactato no sangue (OBLA sobre o torque máximo dos extensores do joelho analisado em diferentes tipos de contração e

  2. Effect of training in minimalist footwear on oxygen consumption during walking and running

    Directory of Open Access Journals (Sweden)

    D Bellar

    2015-05-01

    Full Text Available The present study sought to examine the effect of 5 weeks of training with minimalist footwear on oxygen consumption during walking and running. Thirteen college-aged students (male n=7, female n=6, age: 21.7±1.4 years , height: 168.9±8.8 cm, weight: 70.4±15.8 kg, VO2max: 46.6±6.6 ml · kg -1 · min -1 participated in the present investigation. The participants did not have experience with minimalist footwear. Participants underwent metabolic testing during walking (5.6 km · hr -1 , light running (7.2 km · hr -1 , and moderate running (9.6 km · hr -1 . The participants completed this assessment barefoot, in running shoes, and in minimalist footwear in a randomized order. The participants underwent 5 weeks of training with the minimalist footwear. Afterwards, participants repeated the metabolic testing. Data was analyzed via repeated measures ANOVA. The analysis revealed a significant (F 4,32 = 7.576, ηp 2 =0.408, p≤0.001 interaction effect (time × treatment × speed. During the initial assessment, the minimalist footwear condition resulted in greater oxygen consumption at 9.6 km · hr -1 (p≤0.05 compared to the barefoot condition, while the running shoe condition resulted in greater oxygen consumption than both the barefoot and minimalist condition at 7.2 and 9.6 km · hr -1 . At post-testing the minimalist footwear was not different at any speed compared to the barefoot condition (p> 0.12. This study suggests that initially minimalist footwear results in greater oxygen consumption than running barefoot, however; with utilization the oxygen consumption becomes similar.

  3. Off seasonal and pre-seasonal assessment of circulating energy sources during prolonged running at the anaerobic threshold in competitive triathletes.

    Science.gov (United States)

    Knoepfli, B; Riddell, M C; Ganzoni, E; Burki, A; Villiger, B; von Duvillard, S P

    2004-08-01

    To compare changes in circulating energy sources during prolonged exercise in off season (OS) and pre-season (PS) training of triathletes. Nine athletes of the Swiss national triathlon team (three female, mean (SD) age 28.7 (4.9) years, height 169.8 (6.0) cm, weight 57.0 (6.2) kg, VO(2)max 66.5 (5.3) ml/min/kg; six male, mean (SD) age 24.0 (4.1) years, height 181.4 (6.9) cm, weight 73.5 (6.0) kg, VO(2)max 75.9 (4.9) ml/min/kg) were tested twice (2.5 months apart) during a 25 km aerobic capacity test run at the end of the OS and just before the season. The average training load during the OS was 9.9 h/week, and this increased to 14.4 h/week in the PS. With heart rates as reference, exercise intensity during the aerobic capacity test was 97.0 (4.9)% of the anaerobic threshold and 91.2 (4.5)% of VO(2)max. Blood samples were collected before, during, and after the aerobic capacity test. Samples were collected every 5 km during three minute rest intervals. Blood was analysed for triglyceride (TG), free fatty acids, cholesterol, high density lipoprotein cholesterol, glucose, insulin, lactate, and changes in plasma volume. A two factor (season by distance) repeated measures analysis of variance revealed an increase in capacity for prolonged exercise in the PS by a decrease in running intensity during the aerobic capacity test (% of speed at 2.0 mmol/l lactate threshold, p = 0.008), an increase in running speed at the anaerobic threshold (p = 0.003) and at 4.0 and 2.0 mmol/l (pincrease in the difference in TG at 5-15 km with a concomitant increase at 2.0 mmol/l of the lactate threshold. The peak TG concentrations at 5 km followed by a logarithmic decrease suggest that TG may also provide circulating energy. A greater logarithmic decrease in TG occurred in the PS than in the OS, indicating a higher rate of use. There was an increase in the difference in TG at 5-15 km similar to the increase in the speed at 2.0 mmol/l of the lactate threshold between the two seasons. Glucose

  4. A comparison of the physiological exercise intensity differences between shod and barefoot submaximal deep-water running at the same cadence.

    Science.gov (United States)

    Killgore, Garry L; Coste, Sarah C; O' Meara, Susan E; Konnecke, Cristina J

    2010-12-01

    The purpose of this investigation was to identify whether physiological exercise intensity differed with the use of aquatic training shoes (ATS) during deep-water running (DWR) compared to using a barefoot condition. Eight male intercollegiate (National Collegiate Athletic Association Division III [NCAA III]) varsity distance runners were videotaped from the right sagittal view while running on a treadmill (TR) and while barefoot in deep water at 60-70% of their TR VO2max for 30 minutes. Based on the stride rate of the barefoot DWR trial, a subsequent 30-minute session was completed while wearing ATS. Variables of interest were energy expenditure, oxygen consumption (VO2), heart rate, respiratory exchange ratio (RER), and rating of perceived exertion (RPE). Multivariate omnibus tests revealed statistically significant differences for energy expenditure (p barefoot and shod DWR conditions for energy expenditure (p barefoot. These comparisons also revealed significantly higher RPE and RER values while DWR than those found in TR. Wearing the ATS may be recommended as a method of statistically significantly increasing the exercise intensity while running in deep water as compared to not wearing a shoe. Shod compared to TR yields very small differences, which indicates that the shoes may help better match land-based running exercise intensities.

  5. How does organic matter affect the head velocity and run-out distance of cohesive sediment gravity flows?

    Science.gov (United States)

    Craig, Melissa; Baas, Jaco; Amos, Kathryn; Strachan, Lorna; Baker, Megan

    2016-04-01

    physically cohesive kaolin clay (one of the most common clay minerals on Earth). Provisional results indicate that very small quantities of EPS - several orders of magnitude smaller than the quantity of clay - are sufficient to enhance flocculation and reduce flow velocity compared to a flow that lacks EPS. This finding has the potential to change our understanding of sediment gravity flows in the natural environment, where biological matter is ubiquitous.

  6. No Positive Influence of Ingesting Chia Seed Oil on Human Running Performance

    Directory of Open Access Journals (Sweden)

    David C. Nieman

    2015-05-01

    Full Text Available Runners (n = 24 reported to the laboratory in an overnight fasted state at 8:00 am on two occasions separated by at least two weeks. After providing a blood sample at 8:00 am, subjects ingested 0.5 liters flavored water alone or 0.5 liters water with 7 kcal kg−1 chia seed oil (random order, provided another blood sample at 8:30 am, and then started running to exhaustion (~70% VO2max. Additional blood samples were collected immediately post- and 1-h post-exercise. Despite elevations in plasma alpha-linolenic acid (ALA during the chia seed oil (337% versus water trial (35% (70.8 ± 8.6, 20.3 ± 1.8 μg mL−1, respectively, p < 0.001, run time to exhaustion did not differ between trials (1.86 ± 0.10, 1.91 ± 0.13 h, p = 0.577, respectively. No trial differences were found for respiratory exchange ratio (RER (0.92 ± 0.01, oxygen consumption, ventilation, ratings of perceived exertion (RPE, and plasma glucose and blood lactate. Significant post-run increases were measured for total leukocyte counts, plasma cortisol, and plasma cytokines (Interleukin-6 (IL-6, Interleukin-8 (IL-8, Interleukin-10 (IL-10, and Tumor necrosis factors-α (TNF-α, with no trial differences. Chia seed oil supplementation compared to water alone in overnight fasted runners before and during prolonged, intensive running caused an elevation in plasma ALA, but did not enhance run time to exhaustion, alter RER, or counter elevations in cortisol and inflammatory outcome measures.

  7. EXPLANATORY VARIANCE IN MAXIMAL OXYGEN UPTAKE

    Directory of Open Access Journals (Sweden)

    Jacalyn J. Robert McComb

    2006-06-01

    Full Text Available The purpose of this study was to develop a prediction equation that could be used to estimate maximal oxygen uptake (VO2max from a submaximal water running protocol. Thirty-two volunteers (n =19 males, n = 13 females, ages 18 - 24 years, underwent the following testing procedures: (a a 7-site skin fold assessment; (b a land VO2max running treadmill test; and (c a 6 min water running test. For the water running submaximal protocol, the participants were fitted with an Aqua Jogger Classic Uni-Sex Belt and a Polar Heart Rate Monitor; the participants' head, shoulders, hips and feet were vertically aligned, using a modified running/bicycle motion. A regression model was used to predict VO2max. The criterion variable, VO2max, was measured using open-circuit calorimetry utilizing the Bruce Treadmill Protocol. Predictor variables included in the model were percent body fat (% BF, height, weight, gender, and heart rate following a 6 min water running protocol. Percent body fat accounted for 76% (r = -0.87, SEE = 3.27 of the variance in VO2max. No other variables significantly contributed to the explained variance in VO2max. The equation for the estimation of VO2max is as follows: VO2max ml.kg-1·min-1 = 56.14 - 0.92 (% BF.

  8. 9- and 13-Hydroxy-octadecadienoic acids (9+13 HODE) are inversely related to granulocyte colony stimulating factor and IL-6 in runners after 2h running.

    Science.gov (United States)

    Nieman, David C; Meaney, Mary Pat; John, Casey S; Knagge, Kevin J; Chen, Huiyuan

    2016-08-01

    This study utilized a pro-inflammatory exercise mode to explore potential linkages between increases in 9- and 13-hydroxy-octadecadienoic acid (9+13 HODE) and biomarkers for inflammation, oxidative stress, and muscle damage. Male (N=10) and female (N=10) runners ran at ∼70% VO2max for 1.5h followed by 30min of downhill running (-10%). Blood samples were taken pre-run and immediately-, 1-h-, and 24-h post-run, and analyzed for 9+13 HODE, F2-isoprostanes, six cytokines, C-reactive protein (CRP), creatine kinase (CK), and myoglobin (MYO). Gender groups performed at comparable relative heart rate and oxygen consumption levels during the 2-h run. All outcome measures increased post-run (time effects, P⩽0.001), with levels near pre-run levels by 24h except for CRP, CK, MYO, and delayed onset of muscle soreness (DOMS). Plasma 9+13 HODE increased 314±38.4% post-run (Prun (Pincreased 50.8±8.9% post-run (Prun (P=0.006). Post-run increases were comparable between genders for all outcomes except for 9+13 HODE (interaction effect, P=0.024, post-run tending higher in females), IL-10 (P=0.006, females lower), and DOMS (P=0.029, females lower). The pre-to-post-run increase in 9+13 HODEs was not related to other outcomes except for plasma granulocyte colony stimulating factor (GCSF) (r=-0.710, Pincreases in 9+13 HODEs tended higher in females, and were not related to increases in F2-isoprostanes, muscle damage, or soreness. The negative relationships to GCSF and IL-6 suggest a linkage between 9+13 HODES and exercise-induced neutrophil chemotaxis, degranulation, and inflammation. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. No influence of ischemic preconditioning on running economy.

    Science.gov (United States)

    Kaur, Gungeet; Binger, Megan; Evans, Claire; Trachte, Tiffany; Van Guilder, Gary P

    2017-02-01

    Many of the potential performance-enhancing properties of ischemic preconditioning suggest that the oxygen cost for a given endurance exercise workload will be reduced, thereby improving the economy of locomotion. The aim of this study was to identify whether ischemic preconditioning improves exercise economy in recreational runners. A randomized sham-controlled crossover study was employed in which 18 adults (age 27 ± 7 years; BMI 24.6 ± 3 kg/m(2)) completed two, incremental submaximal (65-85% VO2max) treadmill running protocols (3 × 5 min stages from 7.2-14.5 km/h) coupled with indirect calorimetry to assess running economy following ischemic preconditioning (3 × 5 min bilateral upper thigh ischemia) and sham control. Running economy was expressed as mlO2/kg/km and as the energy in kilocalories required to cover 1 km of horizontal distance (kcal/kg/km). Ischemic preconditioning did not influence steady-state heart rate, oxygen consumption, minute ventilation, respiratory exchange ratio, energy expenditure, and blood lactate. Likewise, running economy was similar (P = 0.647) between the sham (from 201.6 ± 17.7 to 204.0 ± 16.1 mlO2/kg/km) and ischemic preconditioning trials (from 202.8 ± 16.2 to 203.1 ± 15.6 mlO2/kg/km). There was no influence (P = 0.21) of ischemic preconditioning on running economy expressed as the caloric unit cost (from 0.96 ± 0.12 to 1.01 ± 0.11 kcal/kg/km) compared with sham (from 1.00 ± 0.10 to 1.00 ± 0.08 kcal/kg/km). The properties of ischemic preconditioning thought to affect exercise performance at vigorous to severe exercise intensities, which generate more extensive physiological challenge, are ineffective at submaximal workloads and, therefore, do not change running economy.

  10. Biomechanical events in the time to exhaustion at maximum aerobic speed.

    Science.gov (United States)

    Gazeau, F; Koralsztein, J P; Billat, V

    1997-10-01

    Recent studies reported good intra-individual reproducibility, but great inter-individual variation in a sample of elite athletes, in time to exhaustion (tlim) at the maximal aerobic speed (MAS: the lowest speed that elicits VO2max in an incremental treadmill test). The purpose of the present study was, on the one hand, to detect modifications of kinematic variables at the end of the tlim of the VO2max test and, on the other hand, to evaluate the possibility that such modifications were factors responsible for the inter-individual variability in tlim. Eleven sub-elite male runners (Age = 24 +/- 6 years; VO2max = 69.2 +/- 6.8 ml kg-1 min-1; MAS = 19.2 +/- 1.45 km h-1; tlim = 301.9 +/- 82.7 s) performed two exercise tests on a treadmill (0% slope): an incremental test to determine VO2max and MAS, and an exhaustive constant velocity test to determine tlim at MAS. Statistically significant modifications were noted in several kinematic variables. The maximal angular velocity of knee during flexion was the only variable that was both modified through the tlim test and influenced the exercise duration. A multiple correlation analysis showed that tlim was predicted by the modifications of four variables (R = 0.995, P < 0.01). These variables are directly or indirectly in relation with the energic cost of running. It was concluded that runners who demonstrated stable running styles were able to run longer during MAS test because of optimal motor efficiency.

  11. The association between ace gene variation and aerobic capacity in winter endurance disciplines.

    Science.gov (United States)

    Orysiak, J; Zmijewski, P; Klusiewicz, A; Kaliszewski, P; Malczewska-Lenczowska, J; Gajewski, J; Pokrywka, A

    2013-12-01

    The aim of the study was to examine the possible relationship between I/D polymorphism of ACE gene and selected indices of aerobic capacity among male and female athletes practising winter endurance sports. Sixty-six well-trained athletes (female n = 26, male n = 40), aged 18.4 ± 2.8 years, representing winter endurance sports (cross-country skiing, n = 48; biathlon, n = 8; Nordic combined, n = 10) participated in the study. Genotyping for ACE I/D polymorphism was performed using polymerase chain reaction. Maximal oxygen consumption (VO2max), maximal running velocity (Vmax) and running velocity at anaerobic threshold (VAT4) were determined in an incremental test to volitional exhaustion on a motorized treadmill. The ACE genotype had no significant effect on absolute VO2max, relative VO2max (divided by body mass or fat free body mass), VAT4 or Vmax. No interaction effect of gender x ACE genotype was found for each of the examined aerobic capacity indices. ACE gene variation was not found to be a determinant of aerobic capacity in either female or male Polish, well-trained endurance athletes participating in winter sports.

  12. The effect of warm-up on high-intensity, intermittent running using nonmotorized treadmill ergometry.

    Science.gov (United States)

    Brown, Peter I; Hughes, Michael G; Tong, Richard J

    2008-05-01

    The aim of this study was to investigate the effect of previous warming on high-intensity intermittent running using nonmotorized treadmill ergometry. Ten male soccer players completed a repeated sprint test (10 x 6-second sprints with 34-second recovery) on a nonmotorized treadmill preceded by an active warm-up (10 minutes of running: 70% VO2max; mean core temperature (Tc) 37.8 +/- 0.2 degrees C), a passive warm-up (hot water submersion: 40.1 +/- 0.2 degrees C until Tc reached that of the active warm-up; 10 minutes +/- 23 seconds), or no warm-up (control). All warm-up conditions were followed by a 10-minute static recovery period with no stretching permitted. After the 10-minute rest period, Tc was higher before exercise in the passive trial (38.0 +/- 0.2 degrees C) compared to the active (37.7 +/- 0.4 degrees C) and control trials (37.2 +/- 0.2 degrees C; p pre-exercise oxygen consumption and blood lactate concentration; however, heart rate was greater in the active trial (p 0.05), although both were greater than the control. The percentage of decrement in performance fatigue was similar between all conditions (active, 3.4 +/- 1.3%; passive, 4.0 +/- 2.0%; and control, 3.7 +/- 2.4%). We conclude that there is no difference in high-intensity intermittent running performance when preceded by an active or passive warm-up when matched for post-warm-up Tc. However, repeated sprinting ability is significantly improved after both active and passive warm-ups compared to no warm-up.

  13. The Effects of Acute Post Exercise Consumption of Two Cocoa-Based Beverages with Varying Flavanol Content on Indices of Muscle Recovery Following Downhill Treadmill Running

    Directory of Open Access Journals (Sweden)

    Katelyn Peschek

    2013-12-01

    Full Text Available Dietary flavanols have been associated with reduced oxidative stress, however their efficacy in promoting recovery after exercise induced muscle damage is unclear. This study examined the effectiveness of acute consumption of cocoa-flavanols on indices of muscle recovery including: subsequent exercise performance, creatine kinase, muscle tenderness, force, and self-perceived muscle soreness. Eight endurance-trained athletes (VO2max 64.4 ± 7.6 mL/kg/min completed a downhill running protocol to induce muscle soreness, and 48-h later completed a 5-K (kilometer time trial. Muscle recovery measurements were taken at PRE, 24 h-POST, 48 h-POST, and POST-5K. Participants consumed 1.0 g of carbohydrate per kilogram of body weight of a randomly assigned beverage (CHOC: 0 mg flavanols vs. CocoaCHOC: 350 mg flavanols per serving immediately after the downhill run and again 2 h later. The same protocol was repeated three weeks later with the other beverage. An ANOVA revealed no significant difference (p = 0.97 between trials for 5 K completion time (CHOC 1198.3 ± 160.6 s, CocoaCHOC 1195.5 ± 148.8 s. No significant difference was found for creatine kinase (CK levels (p = 0.31, or muscle soreness (p = 0.21 between groups over time. These findings suggest that the acute addition of cocoa flavanols to low-fat chocolate milk offer no additional recovery benefits.

  14. The effects of acute post exercise consumption of two cocoa-based beverages with varying flavanol content on indices of muscle recovery following downhill treadmill running.

    Science.gov (United States)

    Peschek, Katelyn; Pritchett, Robert; Bergman, Ethan; Pritchett, Kelly

    2013-12-20

    Dietary flavanols have been associated with reduced oxidative stress, however their efficacy in promoting recovery after exercise induced muscle damage is unclear. This study examined the effectiveness of acute consumption of cocoa-flavanols on indices of muscle recovery including: subsequent exercise performance, creatine kinase, muscle tenderness, force, and self-perceived muscle soreness. Eight endurance-trained athletes (VO2max 64.4±7.6 mL/kg/min) completed a downhill running protocol to induce muscle soreness, and 48-h later completed a 5-K (kilometer) time trial. Muscle recovery measurements were taken at PRE, 24 h-POST, 48 h-POST, and POST-5K. Participants consumed 1.0 g of carbohydrate per kilogram of body weight of a randomly assigned beverage (CHOC: 0 mg flavanols vs. CocoaCHOC: 350 mg flavanols per serving) immediately after the downhill run and again 2 h later. The same protocol was repeated three weeks later with the other beverage. An ANOVA revealed no significant difference (p=0.97) between trials for 5 K completion time (CHOC 1198.3±160.6 s, CocoaCHOC 1195.5±148.8 s). No significant difference was found for creatine kinase (CK) levels (p=0.31), or muscle soreness (p=0.21) between groups over time. These findings suggest that the acute addition of cocoa flavanols to low-fat chocolate milk offer no additional recovery benefits.

  15. Differences in oxygen uptake but equivalent energy expenditure between a brief bout of cycling and running

    Directory of Open Access Journals (Sweden)

    Bunker Michael P

    2006-01-01

    Full Text Available Abstract Background We examined aerobic and anaerobic exercise energy expenditure and excess post-exercise oxygen consumption (EPOC between a 250 Watt, 1-minute bout of cycling and uphill treadmill running. Methods Fourteen active to well-trained subjects volunteered for the investigation (VO2 max: 57.0 ± 12.9 ml·kg·min-1 cycle; 59.3 ± 13.7 ml·kg·min-1 run; p = 0.44. Anaerobic energy expenditure was estimated from △blood lactate. Statistical analysis was completed using a paired t-test (mean ± SD. Results Perceived exertion did not differ between exercise bouts (14.0 ± 2.3 cycle; 13.2 ± 2.1 run; p = 0.29. Exercise oxygen uptake was significantly greater for running (41.4 ± 6.9 kJ compared to cycling (31.7 ± 7.7 kJ (p = 0.0001. EPOC was not different between cycling and running (p = 0.21 so that exercise oxygen uptake + EPOC was greater for running (103.0 ± 13.5 kJ as compared to cycling (85.4 ± 20.2 kJ; p = 0.008. Anaerobic energy expenditure was significantly greater for cycling (32.7 ± 8.9 kJ versus running (22.5 ± 11.1 kJ (p = 0.009. Aerobic + anaerobic exercise energy expenditure (cycle 64.3 ± 12.2 kJ; run 63.9 ± 10.1 kJ (p = 0.90 and total energy expenditure (including EPOC; cycle 118.0 ± 21.8 kJ; run 125.4 ± 19.1 kJ; p = 0.36 were similar for cycling and running. Conclusion Oxygen-only measures reveal discrepancy in energy expenditure between cycling and uphill running. Measurements of exercise oxygen uptake, △blood lactate and a modified EPOC promote the hypothesis of a similarity in exercise and total energy expenditure between 1-minute work-equivalent bouts of cycling and uphill running.

  16. The effect of endurance training and downhill running on the expression of IL-1β, IL-6, and TNF-α and HSP72 in rat skeletal muscle.

    Science.gov (United States)

    Isanejad, Amin; Saraf, Zahir Hassan; Mahdavi, Mehdi; Gharakhanlou, Reza; Shamsi, Mahdieh Molanouri; Paulsen, Gøran

    2015-06-01

    This study investigated changes in the myokines IL-1β, IL-6, and TNF-α, as well as HSP72, after endurance training and after a session of downhill running. Twenty-eight rats were allocated to four different groups: 1. Eight weeks of endurance training at 65-70% VO2max (Trained); 2. Endurance training and a single session of downhill running on a 16° slope (Trained plus downhill); 3. A single session of downhill running (Sedentary plus downhill); and 4. Sedentary (Control, no exercise). Soleus and extensor digitorum longus (EDL) muscles were harvested 48h after training and/or a single session of downhill running and protein levels of IL-1β, IL-6, TNF-α, and HSP72 were measured and compared to the levels in the control animals. Creatine kinase (CK) was measured in plasma. Endurance training augmented intramuscular levels of HSP72 and IL-6 in both soleus and EDL muscles (p<0.05). Endurance training elevated IL-1β and decreased TNF-α significantly only in EDL (P<0.05). IL-6 increased in both sedentary and trained rats after downhill running (P<0.05), while HSP72 increased only in the previously sedentary rats. CK was lower in trained than sedentary rats after downhill running. In conclusion, endurance training for 8weeks elevated muscular HSP72 protein levels, which might have preconditioned the muscles for a single session of downhill running, as indicated by the CK and HSP72 responses. Interestingly, IL-6 was augmented by endurance training and further increased by downhill running. IL-1β, along with IL-6, was increased by endurance training, and these myokines thus appear to be differently regulated than TNF-α. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Biomechanics of Distance Running.

    Science.gov (United States)

    Cavanagh, Peter R., Ed.

    Contributions from researchers in the field of running mechanics are included in the 13 chapters of this book. The following topics are covered: (1) "The Mechanics of Distance Running: A Historical Perspective" (Peter Cavanagh); (2) "Stride Length in Distance Running: Velocity, Body Dimensions, and Added Mass Effects" (Peter Cavanagh, Rodger…

  18. Factores que afectan al rendimiento en carreras de fondo. [Factors affecting long-distance running performance].

    Directory of Open Access Journals (Sweden)

    Ana Ogueta-Alday

    2016-07-01

    and runners are interested on learning about the factors that affect long-distance running performance. Facing this new reality, scientific literature has been concerned about the aforementioned factors, and the amount of studies has considerably grown. Therefore, the purpose of this review is to analyse factors affecting long-distance running performance from different points of view. Literature review was performed through 3 different databases (Medline, SportDiscus and Google Scholar and the factors were classified into 5 main groups, subdivided into different sections: 1- environmental (air/wind, temperature, humidity, altitude and slope of the ground, 2- training-related (endurance, resistance, training in hot environments and in altitude, 3- physiological (VO2max, thersholds, running economy, age, gender, muscle fibre type, fatigue and race, 4- biomechanical (anthropometry, leg-stiffness, flexibility, foot strike pattern, footwear, foot orthoses and spatio-temporal parameters and 5- psychological (intervention strategies, direction of attention and music. Even though the influence of some of these factors on running performance in quite well-known, the influence of some psychological (direction of attention and music and biomechanical factors (foot strike pattern and spatio-temporal parameters is still unclear. There are few studies or the results cannot be generalized. Future studies and the progress of new technologies and measurement tools will provide a better understanding.

  19. PHYSIOLOGICAL RESPONSES TO ON-COURT VS RUNNING INTERVAL TRAINING IN COMPETITIVE TENNIS PLAYERS

    Directory of Open Access Journals (Sweden)

    Jaime Fernandez -Fernandez

    2011-09-01

    Full Text Available The aim of this study was to compare heart rate (HR, blood lactate (LA and rate of perceived exertion (RPE responses to a tennis-specific interval training (i.e., on-court session with that of a matched-on-time running interval training (i.e., off-court. Eight well-trained, male (n = 4 and female (n = 4 tennis players (mean ± SD; age: 16.4 ± 1.8 years underwent an incremental test where peak treadmill speed, maximum HR (HRmax and maximum oxygen uptake (VO2max were determined. The two interval training protocols (i.e., off- court and on-court consisted of 4 sets of 120 s of work, interspersed with 90 s rest. Percentage of HRmax (95.9 ± 2.4 vs. 96.1 ± 2.2%; p = 0.79, LA (6.9 ± 2.5 vs. 6.2 ± 2.4 mmol·L-1; p = 0.14 and RPE (16.7 ± 2.1 vs. 16.3 ± 1.8; p = 0.50 responses were similar for off-court and on-court, respectively. The two interval training protocols used in the present study have equivalent physiological responses. Longitudinal studies are still warranted but tennis-specific interval training sessions could represent a time-efficient alternative to off-court (running interval training for the optimization of the specific cardiorespiratory fitness in tennis players

  20. Effects of acute supplementation of Panax ginseng on endurance running in a hot & humid environment.

    Science.gov (United States)

    Ping, Fadzel Wong Chee; Keong, Chen Chee; Bandyopadhyay, Amit

    2011-01-01

    Athletes in Malaysia need to perform in a hot and humid environment due to the climatic nature of the country. Chronic supplementation of Panax ginseng (PG) (a deciduous perennial plant belonging to the Araliaceae family) enhances physical performance. As the ergogenic effect of acute supplementation of PG on endurance performance has not been explored in the Malaysian population especially in a hot and humid condition this study was taken up. Nine heat adapted recreational runners (age: 25.4 ± 6.9 yr, body mass: 57.6 ± 8.4 kg; body height: 168.3 ± 7.6 cm) were recruited in this placebo-controlled double-blind randomized study. Subjects ingested 200 mg of PG one hour before the exercise test on treadmill at 70 per cent of their VO2max in a laboratory environment of 31° C and 70 per cent relative humidity. They drank 3 ml/kg body weight of cool water every 20 min during the exercise to prevent adverse effects of dehydration. Blood samples were drawn every 20 min for the analysis of glucose, lactate, insulin and free fatty acids. Oxygen uptake was determined every 20 min while heart rate, body and skin temperatures, and ratings of perceived exertion (RPE) were recorded every 10 min during the trials. Endurance running time to exhaustion did not differ between PG and placebo trials. Heart rate, skin temperature, core body temperature, oxygen uptake, RPE, plasma insulin, glucose, free fatty acid and lactate levels during the endurance exercise did not show any significant differences between the trials. We conclude that acute supplementation of 200 mg of PG did not affect the endurance running performance of the heat-adapted male recreational runners in the heat.

  1. Running the running

    CERN Document Server

    Cabass, Giovanni; Melchiorri, Alessandro; Pajer, Enrico; Silk, Joseph

    2016-01-01

    We use the recent observations of Cosmic Microwave Background temperature and polarization anisotropies provided by the Planck satellite experiment to place constraints on the running $\\alpha_\\mathrm{s} = \\mathrm{d}n_{\\mathrm{s}} / \\mathrm{d}\\log k$ and the running of the running $\\beta_{\\mathrm{s}} = \\mathrm{d}\\alpha_{\\mathrm{s}} / \\mathrm{d}\\log k$ of the spectral index $n_{\\mathrm{s}}$ of primordial scalar fluctuations. We find $\\alpha_\\mathrm{s}=0.011\\pm0.010$ and $\\beta_\\mathrm{s}=0.027\\pm0.013$ at $68\\%\\,\\mathrm{CL}$, suggesting the presence of a running of the running at the level of two standard deviations. We find no significant correlation between $\\beta_{\\mathrm{s}}$ and foregrounds parameters, with the exception of the point sources amplitude at $143\\,\\mathrm{GHz}$, $A^{PS}_{143}$, which shifts by half sigma when the running of the running is considered. We further study the cosmological implications of this anomaly by including in the analysis the lensing amplitude $A_L$, the curvature parameter ...

  2. Effect of concurrent endurance and circuit resistance training sequence on muscular strength and power development.

    Science.gov (United States)

    Chtara, Moktar; Chaouachi, Anis; Levin, Gregory T; Chaouachi, Mustapha; Chamari, Karim; Amri, Mohamed; Laursen, Paul B

    2008-07-01

    The purpose of this study was to examine the influence of the sequence order of high-intensity endurance training and circuit training on changes in muscular strength and anaerobic power. Forty-eight physical education students (ages, 21.4 +/- 1.3 years) were assigned to 1 of 5 groups: no training controls (C, n = 9), endurance training (E, n = 10), circuit training (S, n = 9), endurance before circuit training in the same session, (E+S, n = 10), and circuit before endurance training in the same session (S+E, n = 10). Subjects performed 2 sessions per week for 12 weeks. Resistance-type circuit training targeted strength endurance (weeks 1-6) and explosive strength and power (weeks 7-12). Endurance training sessions included 5 repetitions run at the velocity associated with Vo2max (Vo2max) for a duration equal to 50% of the time to exhaustion at Vo2max; recovery was for an equal period at 60% Vo2max. Maximal strength in the half squat, strength endurance in the 1-leg half squat and hip extension, and explosive strength and power in a 5-jump test and countermovement jump were measured pre- and post-testing. No significant differences were shown following training between the S+E and E+S groups for all exercise tests. However, both S+E and E+S groups improved less than the S group in 1 repetition maximum (p strength and explosive strength and power. Circuit training alone induced strength and power improvements that were significantly greater than when resistance and endurance training were combined, irrespective of the intrasession sequencing.

  3. Velocidade de corrida associada ao consumo máximo de oxigênio em meninos de 10 a 15 anos Running speed associated with maximal oxygen uptake in boys aged 10 to 15 years

    Directory of Open Access Journals (Sweden)

    Fabiana Andrade Machado

    2002-02-01

    Full Text Available O objetivo deste estudo foi determinar a influência da idade cronológica e da maturação biológica sobre o consumo máximo de oxigênio (VO2max e a velocidade de corrida correspondente ao VO2max em crianças e adolescentes brasileiros, do sexo masculino, com idade entre 10 e 15 anos, não praticantes de atividade física sistemática. Participaram do estudo 40 voluntários, divididos em dois grupos, segundo a idade cronológica (GC1 - n = 20; 11,4 ± 0,6 anos; 38,8 ± 8,6kg; 143,6 ± 8,2cm e GC2 - n = 20; 14,1 ± 0,6 anos; 55,9 ± 14,2kg; 163,3 ± 10,2cm e maturação biológica (GB1 - n = 20; estágios 1, 2 e 3; e GB2 - n = 20; estágios 4 e 5. O VO2max foi mensurado em um teste progressivo e intermitente de corrida em esteira rolante, com estágios de três minutos e pausa de 20 segundos, incrementos de 1km/h a começar com 9km/h, até a exaustão voluntária. A velocidade correspondente ao VO2max (vVO2max foi considerada como a menor velocidade em que se observou o maior valor de VO2. A máxima velocidade aeróbia (Va max foi calculada pela fórmula proposta por di Prampero (1986. Houve diferença significante para os valores de VO2max(l/min, Va max(km/he vVO2max(km/h entre os grupos GC1 e GC2 (1,84 ± 0,41 / 2,81 ± 0,61; 11,8 ± 1,2 / 12,6 ± 1,2; 12,1 ± 1,2 / 12,9 ± 1,1, respectivamente, GB1 e GB2 (1,80 ± 0,37 / 2,87 ± 0,56; 12,1 ± 1,2 / 12,9 ± 1,1; 11,8 ± 1,2 / 12,5 ± 1,1, respectivamente, mas não para os valores de VO2max em ml.kg-1.min-1 para todos os grupos (GC1 e GC2: 47,9 ± 6,8 / 50,4 ± 5,5; GB1 e GB2: 47,9 ± 6,8 / 50,3 ± 5,5, respectivamente. Com base nos resultados obtidos, pode-se concluir que o VO2max (l/min, aVa max e a vVO2max têm seus valores aumentados como um provável efeito do crescimento e desenvolvimento, podendo, ainda, expressar melhora da economia de movimento, mesmo em indivíduos não praticantes de atividade física sistemática.The purpose of this study was to determine the influence of

  4. Carbohydrate gel ingestion during running in the heat on markers of gastrointestinal distress.

    Science.gov (United States)

    Sessions, Jenna; Bourbeau, Kelsey; Rosinski, Mattina; Szczygiel, Taylor; Nelson, Rachael; Sharma, Naveen; Zuhl, Micah

    2016-11-01

    The purpose of this study is to measure the effects of carbohydrate ingestion during exercise in the heat by measuring markers of gastrointestinal damage and inflammation. Active subjects (n = 7) completed two 60-min running trials in a heated environment (70% VO2max, 30°C). At minute 20 of exercise, subjects consumed a carbohydrate gel (Cho) (27 g), or a non-carbohydrate placebo (nCho). Plasma endotoxin, I-FABP, TNF-α, IL-6, IL-1β, IL-10, and MCP-1 were measured pre-exercise, 20-min post-exercise, and again 2-h, and 4-h post-exercise. Endotoxin increased 20-min post-exercise compared to pre in the Cho trial only (p = .03). I-FABP levels increased 20-min post-exercise in the Cho trial only compared to pre-exercise (p = .003). I-FABP levels were also increased in Cho trial 20-min post-exercise when compared to same time point in the nCho trial (p = .032). TNF-α increased 20-min post-exercise in the Cho trial only compared to pre (p = .03). Plasma IL-6 concentration increased 20-min post-exercise when compared to pre in both the Cho (p = .002) and nCho (p = .009), but remained elevated at the 2-h time point in the nCho trial (p = .03). I-FABP and several plasma cytokines (TNF-α, MCP-1, Il-6) returned to baseline sooner in the Cho trial. Ingestion of carbohydrate gel during exercise in the heat enhances markers of gastrointestinal wall damage.

  5. The Effect of High Intensity Interval Run Training on Cross-sectional Area of the Vastus Lateralis in Untrained College Students

    Science.gov (United States)

    ESTES, REBEKAH R.; MALINOWSKI, AMY; PIACENTINI, MEREDITH; THRUSH, DAVID; SALLEY, ERIC; LOSEY, CASSIDY; HAYES, ERIK

    2017-01-01

    Aerobic cycling has been repeatedly shown to induce hypertrophy in skeletal muscle across a variety of populations, while there has been a lack of investigation into the impact of running upon hypertrophy. An increasingly popular model of aerobic exercise is high-intensity interval training (HIIT); in addition to its positive impact upon cardiovascular health, HIIT may be sufficient for inducing significant muscular hypertrophy. Therefore, the purpose of this investigation was to examine the influence of a high-intensity interval running protocol upon hypertrophy of the vastus lateralis in an untrained, young population. Twelve recreationally active university students (Male: 2; Female: 10; 19.9±0.5 yr.; 169.8±1.9 cm; 63.8±2.3 kg; VO2max: 42.1±1.6 ml•kg−1min−1) completed 24.5±0.6 sessions of high-intensity interval run training over 10 weeks. The protocol consisted of four sets of 4 minutes running at 90–95% HRmax followed by 3 minutes active rest at 70% HRmax. Relative and absolute aerobic capacity increased 5.2±2.2% and 6.0±2.3% respectively as a result of the intervention (p< 0.05). Cross-sectional area (CSA) of the vastus lateralis was measured via panoramic ultrasound imaging pre- and post-intervention. Following the protocol, CSA of the intervention group was 10.6±2.7% greater (p< 0.05), while that of the control group did not change. This is the first data to demonstrate hypertrophy of the vastus lateralis in a young population following a running protocol. These data support the existing body of evidence suggesting aerobic exercise to be an effective mode of improving cardiorespiratory fitness as well as increasing whole muscle size of the quadriceps. PMID:28479954

  6. Running Away

    Science.gov (United States)

    ... Emergency Room? What Happens in the Operating Room? Running Away KidsHealth > For Kids > Running Away Print A ... life on the streets. continue The Reality of Running Away When you think about running away, you ...

  7. The acute effects of intermittent treadmill running on hunger and plasma acylated ghrelin concentration in individuals with obesity

    Directory of Open Access Journals (Sweden)

    Gholipour M

    2011-05-01

    Full Text Available "n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: Body weight is regulated by both food intake and energy expenditure. Ghrelin, a hormone produced by the stomach and pancreas, enhances appetite. This study was undertaken to determine the effects of intermittent treadmill running on acylated ghrelin and appetite in individuals with obesity."n"nMethods : Nine inactive male students, with a mean age of 20.56±0.48 yrs, a body mass index of 32.68±0.84 kg/m2 and a maximum oxygen uptake of 34.21±1.48 ml/kg/min, participated in the study in two trials (control and exercise in a counterbalanced, randomized design. The protocol included intermittent running with a constant intensity at 65% of VO2 max on a treadmill. Blood samples were collected before, during, and 2h after cessation of the exercise."n"nResults : Acylated ghrelin concentrations and hunger ratings decreased significantly in the second phase and remained lower than baseline (P=0.006 and P=0.002, respectively at the end of the exercise. The total area under the curve values and hunger ratings (all P<0.0005 were significantly lower in the exercise trial compared with the control state. Similarly, growth hormone rose significantly at the second phase and remained higher than baseline (P=0.033 at the

  8. High versus Moderate Intensity Running Exercise to Impact Cardiometabolic Risk Factors: The Randomized Controlled RUSH-Study

    Directory of Open Access Journals (Sweden)

    Wolfgang Kemmler

    2014-01-01

    Full Text Available Aerobic exercise positively impacts cardiometabolic risk factors and diseases; however, the most effective exercise training strategies have yet to be identified. To determine the effect of high intensity (interval training (HI(IT versus moderate intensity continuous exercise (MICE training on cardiometabolic risk factors and cardiorespiratory fitness we conducted a 16-week crossover RCT with partial blinding. Eighty-one healthy untrained middle-aged males were randomly assigned to two study arms: (1 a HI(IT-group and (2 a sedentary control/MICE-group that started their MICE protocol after their control status. HI(IT focused on interval training (90 sec to 12 min >85–97.5% HRmax intermitted by active recovery (1–3 min at 65–70% HRmax, while MICE consisted of continuous running at 65–75% HRmax. Both exercise groups progressively performed 2–4 running sessions/week of 35 to 90 min/session; however, protocols were adjusted to attain similar total work (i.e., isocaloric conditions. With respect to cardiometabolic risk factors and cardiorespiratory fitness both exercise groups demonstrated similar significant positive effects on MetS-Z-Score (HI(IT: -2.06±1.31, P=.001 versus MICE: -1.60±1.77, P=.001 and (relative VO2max (HI(IT: 15.6±9.3%, P=.001 versus MICE: 10.6 ± 9.6%, P=.001 compared with the sedentary control group. In conclusion, both exercise programs were comparably effective for improving cardiometabolic indices and cardiorespiratory fitness in untrained middle-aged males.

  9. トレ-ニングに伴う中長距離走の競技成績の変動とV^^・O_2 max,換気性閾値および乳酸性閾値の関連性

    OpenAIRE

    小原, 達朗

    1990-01-01

    Six male and four female middle and long distance runners in university were examined to change of endurance performance, VO2max, ventilatory threshold (VT), and lactate threshiold (LT) with eight months training. They were trained the interval running of 1000m and the pace running durinng 60 minutes in addition to the ordinary training. The results as follows. 1. The values of VO2max, in male and female in this study were 71.17ml/kg/min and 65.95ml/kg/min,respectivery. The values of % VO2max...

  10. 女子アスリートにおけるトレッドミル走行または歩行によるVO_2-kineticsでの運動能力の評価

    OpenAIRE

    田中, 繁宏; 垂井, 彩未; 渡辺, 好美; 廣瀬, 由美子; 四元, 美帆; 中村, 真理子

    2007-01-01

    To evaluate the exercise performance of the time constant in the VO_2-kinetics in female athletes, we made examination of VO_2 max and the oxgen uptake kinetics (VO_2) during treadmill running (seven females) or walking (eight females). In the study of the treadmill running, the time constant of the VO_2-kinetics was significantly correlated with VO_2 max. In the study of the treadmill walking, however the time constant of the VO_2-kinetics was not significantly correlated with VO_2 max. Our ...

  11. Effect of Wheelchair Running on Recovery of Blood Lactate and Physical Performance after High-Intensity Intermittent Exercise – An Experimental Trial

    Directory of Open Access Journals (Sweden)

    Karthikeyan G

    2012-04-01

    Full Text Available Background and Purpose: Repetitive sprint sport players perform high intensity exercise only for a small percentage of a total game and such periods are often instrumental in determining the eventual outcome. Recovery is a key factor for performance, and constant lack of recovery or insufficient recovery turns into overtraining which is detrimental in achieving peak performance. The purpose was to find out the effect of wheelchair running on the physical performance recovery after high-intensity intermittent exercise. Method: Ten sportsmen having the age range from 20 to 29, VO2max Ranges from 60.51 to 64.29 were randomly divided into experimental and control groups. After filling pre-participation questionnaire and 30-min of supine rest, Blood lactate and the field tests for the measurement of static balance, power, speed and agility were applied. The subjects were made to run in the treadmill and to increase the intensity to reach the Target Heart Rate (THR. After 1-min the subjects were given rest for 15-s and after that they started exercise again and thus the subjects completed several bouts of such exercises until exhaustion followed by either Passive rest or wheelchair running for the duration of 10 minutes. Parameters were measures after completed the exercise bout and after the recovery. Results: After the recovery in experimental group significant improvement found only in blood lactate (p<0.01 and no significant changes found in other parameters while in control group no significant changes found in all parameters. There was no significant difference found in all the parameters including blood lactate between the groups. Conclusion: Both wheelchair running and passive recovery are same in the efficiency of blood lactate removal and restoration of physical performance following intense intermittent exercise.

  12. Critical wind velocities for several kinds of typical vehicle running on a cable-stayed bridge deck%几种典型车辆在斜拉桥桥面行驶的临界风速研究

    Institute of Scientific and Technical Information of China (English)

    马麟; 韩万水; 刘健新; 李加武

    2011-01-01

    The critical wind velocity and running velocity were studied for three kinds of typical vehicle running on a cable-stayed bridge deck under action of strong side wind. The effects of the bridge's side buffeting and the following coordinate features of the vehicle's moving equations on the vehicle side deviation relative to the bridge deck were analyzed, the calculation formulas of its relative side slipping and velocity were obtained. Based on previous studies, a wind-vehicle-bridge coupling vibration system including vehicle side deviation and driver's behavior was studied, and the corresponding simulation code was improved and tested. A cable-stayed bridge was taken as an example, critical wind velocities of three kinds of typical automobile running on the bridge deck were obtained. Results showed that the critical wind velocity is not significantly influenced by controlling objectives of driver behavior; the accident types of different vehicles are possibly different; for box-type truck, its critical wind velocity of side slipping is always lower than that of overturning; but for cars like Santana and Jia-bao, overturning accident plays a controlling role when running velocity is high, while side slipping accident does when running velocity is low.%研究强侧风作用下三种典型汽车在斜拉桥桥面行驶时的临界风速和车速.分析汽车运动方程的随动坐标特性和桥梁的侧向抖振对汽车相对桥面侧偏的影响,得到侧偏位移及速率的计算式,在以往基础上,研究了考虑车辆侧偏和驾驶员行为的风-车-桥空间耦合振动系统,完善了仿真分析程序的功能.以某斜拉桥为实例,分析三种典型车辆在桥面行使的临界风速.分析结果表明:采用控制重心还是前轮侧滑的驾驶员模型不显著影响桥面汽车临界风速的大小;不同类型汽车的事故原因可能不同,对于箱式货车,侧滑事故起控制作用,对于桑塔纳和一汽佳宝,车速高时,侧倾

  13. Debris Flow Run Out Distance Prediction Based on the Velocity Decreasing Coefficient%基于流速衰减特征的泥石流冲出距离预测方法

    Institute of Scientific and Technical Information of China (English)

    铁永波

    2012-01-01

    The prediction of debris-flow rum out distance is crucial to it' s hazards assessment and mitigation planning. Based on the phenomenon of debris flow velocity decreasing in inundate area, this paper give the general idea of attenuation coefficient. After the definition interpreting and the formula constructing of attenuation coefficient, this paper put forward a method to debris flow run out distance prediction based on the definition of velocity attenuation coefficient. Finally, take Gangou debris flow which locate in Luding country (Sichuan province) as an example to calculating it's run out distance. The result show that when the velocity of debris flow is higher than 15% of beginning velocity, the decreasing degree of debris flow velocity is obvious, and when the velocity of debris flow is lower than 15% of beginning velocity, the decreasing degree of debris flow velocity is slow. This research is significance to debris flow hazards assessment and mitigation.%泥石流冲出距离的确定是泥石流灾害评价及防治中的关键环节.基于泥石流在堆积区流速的变化特征,提出了泥石流流速“衰减系数”的概念.通过对泥石流流速衰减系数的定义和计算公式的推导,提出了一种基于泥石流流速衰减系数来确定泥石流冲出距离的新方法,并以四川省泸定县干沟泥石流为实例进行计算和验证.研究结果表明:当干沟泥石流在堆积区的流速大于初始(沟口)流速的15%时,流速的衰减程度极为显著;而当堆积区流速小于初始速度的15%时,流速的衰减极为缓慢.研究结果对泥石流灾害的危险性评价及防灾减灾具有一定的理论和实践意义.

  14. Effects of static stretching on 1-mile uphill run performance.

    Science.gov (United States)

    Lowery, Ryan P; Joy, Jordan M; Brown, Lee E; Oliveira de Souza, Eduardo; Wistocki, David R; Davis, Gregory S; Naimo, Marshall A; Zito, Gina A; Wilson, Jacob M

    2014-01-01

    It is previously demonstrated that static stretching was associated with a decrease in running economy and distance run during a 30-minute time trial in trained runners. Recently, the detrimental effects of static stretching on economy were found to be limited to the first few minutes of an endurance bout. However, economy remains to be studied for its direct effects on performance during shorter endurance events. The aim of this study was to investigate the effects of static stretching on 1-mile uphill run performance, electromyography (EMG), ground contact time (GCT), and flexibility. Ten trained male distance runners aged 24 ± 5 years with an average VO2max of 64.9 ± 6.5 mL·kg-1·min-1 were recruited. Subjects reported to the laboratory on 3 separate days interspersed by 72 hours. On day 1, anthropometrics and V[Combining Dot Above]O2max were determined on a motor-driven treadmill. On days 2 and 3, subjects performed a 5-minute treadmill warm-up and either performed a series of 6 lower-body stretches for three 30-second repetitions or sat still for 10 minutes. Time to complete a 1-mile run under stretching and nonstretching conditions took place in randomized order. For the performance run, subjects were instructed to run as fast as possible at a set incline of 5% until a distance of 1 mile was completed. Flexibility from the sit and reach test, EMG, GCT, and performance, determined by time to complete the 1-mile run, were recorded after each condition. Time to complete the run was significantly less (6:51 ± 0:28 minutes) in the nonstretching condition as compared with the stretching condition (7:04 ± 0:32 minutes). A significant condition-by-time interaction for muscle activation existed, with no change in the nonstretching condition (pre 91.3 ± 11.6 mV to post 92.2 ± 12.9 mV) but increased in the stretching condition (pre 91.0 ± 11.6 mV to post 105.3 ± 12.9 mV). A significant condition-by-time interaction for GCT was also present, with no changes in

  15. The occurrence of core muscle fatigue during high-intensity running exercise and its limitation to performance: the role of respiratory work.

    Science.gov (United States)

    Tong, Tomas K; Wu, Shing; Nie, Jinlei; Baker, Julien S; Lin, Hua

    2014-05-01

    This study investigated the occurrence of core muscle fatigue during high-intensity running exercise and its limitation to exercise performance. A secondary aim was to investigate whether respiratory muscle work performed during intense running periods, would contribute to core muscle fatigue. Nine male recreational runners were recruited for two reasons; (1) to perform a continuous treadmill run at 85% VO2max with and without core muscle fatigue in the CR_F and CR trials, respectively; and (2) to mimic the treadmill run-induced respiratory response recorded in the CR trial while subjects were free of whole-body exercise (Mimic trial). The changes in global core muscle function with fatigue in this study were evaluated by performing a sport-specific endurance plank test (SEPT), and the associated influence on running performance was examined by comparing the time to exhaustion during the treadmill run between the CR and CR_F trials. Subsequent to the treadmill run in the CR trial, SEPT (255.7 ± 85.3 vs 177.3 ± 80.6 s) was reduced from baseline in all runners. The reduction correlated (r = 0.67) with the concomitant decline in inspiratory muscle function revealed by maximal inspiratory mouth pressure (PImax: 151.3 ± 18.2 vs 133.3 ± 17.2 cmH2O, p core muscle workout in the CR_F trial, the running capacity was impaired significantly (10.7 ± 4.5 vs 6.5 ± 2.0 min, p core muscle fatigue in runners. The core muscle fatigue, which may be partly attributed to the corresponding respiratory work, may limit their running endurance. Inspiratory muscle function appears to be essential for core stabilization during the intense running. Key pointsA high-intensity maximum run may induce core muscle fatigue in runners. The core muscle fatigue, which may be partly attributed to the corresponding respiratory work, may limit their running endurance.In support of previous notion, inspiratory muscles may share the work of core stabilization during intense exercise, while

  16. Postrace upper respiratory tract 'infections' in ultra- marathoners ...

    African Journals Online (AJOL)

    Enrique

    race period; and (ii) nutritional and pharmacological intervention ... SPORTS MEDICINE VOL 16 NO.1 2004. 3. REVIEW ... Australian Institute of Sport and University of Queensland ..... lowing 2.5 hours of treadmill running at 70% VO2max.

  17. Ergogenic effects of quercetin supplementation in trained rats

    National Research Council Canada - National Science Library

    Casuso, Rafael A; Martínez-Amat, Antonio; Martínez-López, Emilio J; Camiletti-Moirón, Daniel; Porres, Jesus M; Aranda, Pilar

    2013-01-01

    .... During six weeks of treatment volume parameters of training were recorded, and after six weeks all groups performed a maximal graded VO2 max test and a low-intensity endurance run-to-fatigue test...

  18. Effect of low- intensity continuous training on lung function and ...

    African Journals Online (AJOL)

    African Health Sci

    training (20-30 minutes of running at 40% of maximum oxygen uptake (VO2max). Lung function and .... index and the correlation index. Recovery index = Regression index x correlation Index ..... Fitness Parameters in Athletes. World Applied ...

  19. Measuring fitness of Kenyan children with polyparasitic infections using the 20-meter shuttle run test as a morbidity metric.

    Directory of Open Access Journals (Sweden)

    Amaya L Bustinduy

    2011-07-01

    Full Text Available To date, there has been no standardized approach to the assessment of aerobic fitness among children who harbor parasites. In quantifying the disability associated with individual or multiple chronic infections, accurate measures of physical fitness are important metrics. This is because exercise intolerance, as seen with anemia and many other chronic disorders, reflects the body's inability to maintain adequate oxygen supply (VO(2 max to the motor tissues, which is frequently linked to reduced quality-of-life in terms of physical and job performance. The objective of our study was to examine the associations between polyparasitism, anemia, and reduced fitness in a high risk Kenyan population using novel implementation of the 20-meter shuttle run test (20mSRT, a well-standardized, low-technology physical fitness test.Four villages in coastal Kenya were surveyed during 2009-2010. Children 5-18 years were tested for infection with Schistosoma haematobium (Sh, malaria, filaria, and geohelminth infections by standard methods. After anthropometric and hemoglobin testing, fitness was assessed with the 20 mSRT. The 20 mSRT proved easy to perform, requiring only minimal staff training. Parasitology revealed high prevalence of single and multiple parasitic infections in all villages, with Sh being the most common (25-62%. Anemia prevalence was 45-58%. Using multiply-adjusted linear modeling that accounted for household clustering, decreased aerobic capacity was significantly associated with anemia, stunting, and wasting, with some gender differences.The 20 mSRT, which has excellent correlation with VO(2, is a highly feasible fitness test for low-resource settings. Our results indicate impaired fitness is common in areas endemic for parasites, where, at least in part, low fitness scores are likely to result from anemia and stunting associated with chronic infection. The 20 mSRT should be used as a common metric to quantify physical fitness and compare sub

  20. The impact of a pre-loaded multi-ingredient performance supplement on muscle soreness and performance following downhill running.

    Science.gov (United States)

    Ormsbee, Michael J; Ward, Emery G; Bach, Christopher W; Arciero, Paul J; McKune, Andrew J; Panton, Lynn B

    2015-01-01

    The effects of multi-ingredient performance supplements (MIPS) on perceived soreness, strength, flexibility and vertical jump performance following eccentric exercise are unknown. The purpose of this study was to determine the impact of MIPS (NO-Shotgun®) pre-loaded 4 weeks prior to a single bout of downhill running (DHR) on muscle soreness and performance. Trained male runners (n = 20) were stratified by VO2max, strength, and lean mass into two groups; MIPS (n = 10) ingested one serving daily of NO-Shotgun® for 28 days and 30 min prior to all post-testing visits, Control (CON; n = 10) consumed an isocaloric maltodextrin placebo in an identical manner as MIPS. Perceived soreness and performance measurements (strength, flexibility, and jump height) were tested on 6 occasions; 28 days prior to DHR, immediately before DHR (PRE), immediately post (POST) DHR, 24, 48, and 72 hr post-DHR. Perceived soreness significantly increased (p < 0.05) post DHR compared to PRE at all time-points, with no difference between groups. Creatine kinase (CK) and lactate dehydrogenase (LDH) increased over time (p < 0.001) with no group x time interactions (p = 0.236 and p = 0.535, respectively). Significant time effects were measured for strength (p = 0.001), flexibility (p = 0.025) and vertical jump (p < 0.001). There were no group x time interactions for any performance measurements. Consumption of MIPS for 4 weeks prior to a single bout of DHR did not affect perceived soreness, muscle damage, strength, flexibility, or jump performance compared to an isocaloric placebo in trained male runners following a single bout of DHR.

  1. Heat acclimation responses of an ultra-endurance running group preparing for hot desert-based competition.

    Science.gov (United States)

    Costa, Ricardo J S; Crockford, Michael J; Moore, Jonathan P; Walsh, Neil P

    2014-01-01

    Heat acclimation induces adaptations that improve exercise tolerance in hot conditions. Here we report novel findings into the effects of ultra-marathon specific exercise load in increasing hot ambient conditions on indices of heat acclimation. Six male ultra-endurance runners completed a standard pre-acclimation protocol at 20°C ambient temperature (T amb), followed by a heat acclimation protocol consisting of six 2 h running exercise-heat exposures (EH) at 60% VO2max on a motorised treadmill in an environmental chamber. Three EH were performed at 30°C T amb, followed by another three EH at 35°C T amb. EH were separated by 48 h within T amb and 72 h between T amb. Nude body mass (NBM), blood and urine samples were collected pre-exercise; while NBM and urine were collected post-exercise. Rectal temperature (T re), heart rate (HR), thermal comfort rating (TCR) and rating of perceived exertion were measured pre-exercise and monitored every 5 min during exercise. Water was provided ad libitum during exercise. Data were analysed using a repeated measures and one-way analysis of variance (ANOVA), with post hoc Tukey's HSD. Significance was accepted as Pheat acclimation in all ultra-endurance runners. Further, heat acclimation responses occurred with increasing EH to 35°C T amb. Preventing exertional heat illnesses and optimising performance outcomes in ultra-endurance runners may occur with exposure to at least 2 h of exercise-heat stress on at least two occasions in the days leading up to multi-stage ultra-marathon competition in the heat.

  2. Neuromuscular characteristics and fatigue in endurance and sprint athletes during a new anaerobic power test.

    Science.gov (United States)

    Paavolainen, L; Häkkinen, K; Nummela, A; Rusko, H

    1994-01-01

    The purpose of this study was to investigate neuromuscular and energy performance characteristics of anaerobic power and capacity and the development of fatigue. Ten endurance and ten sprint athletes performed a new maximal anaerobic running power test (MARP), which consisted of n x 20-s runs on a treadmill with 100-s recovery between the runs. Blood lactate concentration [la-]b was measured after each run to determine submaximal and maximal indices of anaerobic power (P3 mmol.l-1, P5 mmol.l-1, P10 mmol.l-1 and Pmax) which was expressed as the oxygen demand of the runs according to the American College of Sports Medicine equation: the oxygen uptake (ml.kg-1.min-1) = 0.2 x velocity (m.min-1) + 0.9 x slope of treadmill (frac) x velocity (m.min-1) + 3.5. The height of rise of the centre of gravity of the counter movement jumps before (CMJrest) and during (CMJ) the MARP test, as well as the time of force production (tF) and electromyographic (EMG) activity of the leg muscles of CMJ performed after each run were used to describe the neuromuscular performance characteristics. The maximal oxygen uptake (VO2max), anaerobic and aerobic thresholds were determined in the VO2max test, which consisted of n x 3-min runs on the treadmill.(ABSTRACT TRUNCATED AT 250 WORDS)

  3. CONCURRENT TRAINING IN PREPUBESCENT CHILDREN: THE EFFECTS OF 8 WEEKS OF STRENGTH AND AEROBIC TRAINING ON EXPLOSIVE STRENGTH AND V_O2MAX

    OpenAIRE

    Alves, Ana; Marta, Carlos; Neiva, Henrique; Izquierdo, Mikel; Marques, Mário

    2016-01-01

    Concurrent training in prepubescent children: the effects of 8 weeks of strength and aerobic training on explosive strength and V_ O2max. J Strength Cond Res 30(7): 2019–2032, 2016— The purpose of this study was to compare the effects of 8-week training periods of strength training alone (GS), combined strength and aerobic training in the same session (GCOM1), or in 2 different sessions (GCOM2) on explosive strength and maximal oxygen uptake (V_ O2max) in prepubescent children. Of note, 168 h...

  4. Influência do estado nutricional e do VO2max nos níveis de adiponectina em homens acima de 35 anos

    OpenAIRE

    Martinez,Eduardo Camillo; Fortes,Macos de Sá Rego; Anjos,Luiz Antônio dos

    2011-01-01

    FUNDAMENTO: A adiponectina é considerada importante fator na patogênese das doenças cardiovasculares e metabólicas, por suas propriedades antiaterogênicas e antiinflamatórias. Poucos estudos, entretanto, sugerem a existência de relação direta entre os níveis de adiponectina e os níveis de condicionamento cardiorrespiratório e atividade física. OBJETIVO: Verificar a influência do estado nutricional e do condicionamento cardiorrespiratório nos níveis plasmáticos de adiponectina em homens adulto...

  5. La valoración del VO2 max. y su relación con el riesgo cardiovascular como medio de enseñanza-aprendizaje

    OpenAIRE

    Corral Pernía, Juan Antonio; Castillo Andrés, Óscar del

    2010-01-01

    En la actualidad educativa consideramos que es fundamental la relación de la teoría con la práctica, de ahí que a través de este estudio hayamos perseguido que el alumno realice una valoración de la condición física centrándonos en el test de Course Navette para obtener la potencia aeróbica máxima y relacionar dichos resultados con la actividad física y la salud. De esta manera, presentamos los resultados de dicho Test obtenidos por 57 sujetos (n1= 43 hombres; n2= 14 mujeres), ...

  6. Determination of Aerobic Power Through a Specific Test for Taekwondo - A Predictive Equation Model

    Directory of Open Access Journals (Sweden)

    Rocha Fernando P.S.

    2016-12-01

    Full Text Available Our aim was to verify the concurrent validity of a maximal taekwondo specific test (TST to predict VO2max through an explanatory model. Seventeen elite male taekwondo athletes (age: 17.59 ± 4.34 years; body height: 1.72 ± 6.5 m; body mass: 61.3 ± 8.7 kg performed two graded maximal exercise tests on different days: a 20 m multistage shuttle run test (SRT and an incremental TST. We recorded test time, VO2max, ventilation, a heart rate and time to exhaustion. Significant differences were found between observed and estimated VO2max values [F (2, 16 = 5.77, p < 0.01]; post-hoc subgroup analysis revealed the existence of significant differences (p = 0.04 between the estimated VO2max value in the SRT and the observed value recorded in the TST (58.4 ± 6.4 ml/kg/min and 52.6 ± 5.2 ml/kg/min, respectively. Our analysis also revealed a moderate correlation between both testing protocols regarding VO2max (r = 0.70; p = 0.005, test time (r = 0.77; p = 0.02 and ventilation (r = 0.69; p = 0.03. There was no proportional bias in the mean difference (t = -1.04; p = 0.313, and there was a level of agreement between both tests. An equation/model was used to estimate VO2max during the TST based on the mean heart rate, test time, body height and mass, which explained 74.3% of the observed VO2max variability. A moderate correlation was found between the observed and predicted VO2max values in the taekwondo TST (r = 0.74, p = 0.001. Our results suggest that an incremental specific test estimates VO2max of elite taekwondo athletes with acceptable concurrent validity.

  7. The effects of breathing a helium-oxygen gas mixture on maximal pulmonary ventilation and maximal oxygen consumption during exercise in acute moderate hypobaric hypoxia.

    Science.gov (United States)

    Ogawa, Takeshi; Calbet, Jose A L; Honda, Yasushi; Fujii, Naoto; Nishiyasu, Takeshi

    2010-11-01

    To test the hypothesis that maximal exercise pulmonary ventilation (VE max) is a limiting factor affecting maximal oxygen uptake (VO2 max) in moderate hypobaric hypoxia (H), we examined the effect of breathing a helium-oxygen gas mixture (He-O(2); 20.9% O(2)), which would reduce air density and would be expected to increase VE max. Fourteen healthy young male subjects performed incremental treadmill running tests to exhaustion in normobaric normoxia (N; sea level) and in H (atmospheric pressure equivalent to 2,500 m above sea level). These exercise tests were carried out under three conditions [H with He-O(2), H with normal air and N] in random order. VO2 max and arterial oxy-hemoglobin saturation (SaO(2)) were, respectively, 15.2, 7.5 and 4.0% higher (all p max, 171.9 ± 16.1 vs. 150.1 ± 16.9 L/min; VO2 max, 52.50 ± 9.13 vs. 48.72 ± 5.35 mL/kg/min; arterial oxyhemoglobin saturation (SaO(2)), 79 ± 3 vs. 76 ± 3%). There was a linear relationship between the increment in VE max and the increment in VO2 max in H (r = 0.77; p VO2 max, both groups showed increased VE max and SaO(2) in H with He-O(2), but VO2 max was increased only in the high VO2 max group. These findings suggest that in acute moderate hypobaric hypoxia, air-flow resistance can be a limiting factor affecting VE max; consequently, VO2 max is limited in part by VE max especially in subjects with high VO2 max.

  8. Effect of compression stockings on physiological responses and running performance in division III collegiate cross-country runners during a maximal treadmill test.

    Science.gov (United States)

    Rider, Brian C; Coughlin, Adam M; Hew-Butler, Tamara D; Goslin, Brian R

    2014-06-01

    There is a growing trend for runners to use compression stockings (CS) to improve performance. The purpose of this study was to determine the effect of CS on physiological variables associated with running performance. Participants were 10 NCAA division III cross-country runners. The study used a randomized, crossover design with 2 conditions (with CS and without CS). Both conditions consisted of a maximal treadmill test that involved 3-minute stages of increasing speed and incline, separated by a minute and one-half walking recovery stage. Seven days later, the participants repeated the maximal test but switched CS condition. Heart rate, blood lactate (BLa), blood lactate threshold, maximal oxygen consumption (VO2max), respiratory exchange ratio, rating of perceived exertion, and time to fatigue were measured. Before and during the maximal treadmill tests, the variables showed no significant difference (p ≤ 0.05) between the CS conditions. Blood lactate was lower while wearing CS when measured during recovery at the 1-minute (CS = 13.3 ± 2.9 mmol · L(-1), non-CS = 14.8 ± 2.8 mmol · L(-1), p = 0.03) and the 5-minute (CS = 11.0 ± 2.7 mmol · L(-1), non-CS = 12.8 ± 2.8 mmol · L(-1), p = 0.02) periods. Time to fatigue was longer without CS (CS = 23.570 ± 2.39 minutes, non-CS = 23.93 ± 2.49 minutes, p = 0.04). These findings suggest that CS may not improve running performance, but could lend credence to certain manufacturers' claims of improved recovery through lower BLa values after exercise.

  9. Comparação do ângulo da articulação subtalar durante velocidades submáximas de corrida Comparison of the subtalar joint angle during submaximal running speeds

    Directory of Open Access Journals (Sweden)

    Leonardo Alexandre Peyré Tartaruga

    2005-01-01

    Full Text Available O objetivo foi descrever o comportamento da pronação máxima (PM, da velocidade máxima de pronação (VP e do cruzamento linear (CL dos pés direito e esquerdo, de 23 corredores de rendimento, durante corrida em esteira rolante, em velocidades de 11 e 13 km.h-1 para mulheres e, 14 e 16 km.h-1 para homens, relacionadas a uma média de 70% e 75% do consumo máximo de Oxigênio (VO2máx. A análise estatística (Teste T de Students para amostras dependentes e independentes, com pThe objective was to describe the behavior of the maximum pronation (MP, of the maximum pronation speed (PS and of the linear crossover (LC of the right and left feet of 23 distance runners during treadmill running, at speeds ranging from 11 to 13 km.h-1 for female athletes and from 14 to 16 km.h-1 for male athletes, related to a average of 70% - 75% of the maximum aerobic power (VO2max. The statistical analysis (Student's T-Test for dependent and independent samples, p<0.05 showed that, by increasing submaximal running power, there was a significant increase on MP, and by increasing running linear speed, the PS was significantly higher. Regarding LC, we believe that this is biased by the running technique used by each runner.

  10. Effect of work duration on physiological and rating scale of perceived exertion responses during self-paced interval training.

    Science.gov (United States)

    Seiler, Stephen; Sjursen, Jarl Espen

    2004-10-01

    This study compared running velocity, physiological responses, and perceived exertion during self-paced interval training bouts differing only in work bout duration. Twelve well-trained runners (nine males, three females, 28+/-5 years, VO2 max 65+/-6 mL min(-1) kg(-1)) performed preliminary testing followed by four "high-intensity" interval sessions (Latin squares, 1 session week(-1) over 4 weeks) consisting of 24 x 1, 12 x 2, 6 x 4, or 4 x 6-min running bouts with a 1:1 work-to-rest interval (total session duration 48 min). The average running velocity decreased (93%, 88%, 86%, 84% vVO2 max, P VO2 averaged about 92+/-4% of VO2 max for 2-, 4-, and 6-min intervals compared with only 82+/-5% for 1-min bouts (P VO2 and heart rate during 4-min intervals. The average RPEpeak (rating scale of perceived exertion) was approximately 17+/-1 for all four interval sessions. RPE increased by 2-4 U during an interval training session. The mean lactate concentration was similar across sessions (4.3+/-1.1-4.6+/-1.5 mmol L(-1)). Under self-paced conditions, well-trained runners perform "high-intensity" intervals at an RPE of approximately 17, independent of interval duration. The optimal interval duration for eliciting a high physiological load is 3-5 min under these training conditions. Increases in RPE during an interval bout are not associated with increasing blood lactate concentration.

  11. Alternating Days of Intermittent Hypoxic Exposure (IHE) on Physical and Cognitive Performance

    Science.gov (United States)

    2011-03-01

    SL vs. NH vs. HH) were analyzed. Seven well-conditioned (average VO2 max = 57 mL -1. Kg -1. min) male subjects (30.4 ± 8.7 yrs) completed the study...Significant physiological differences in VO2 max (pɘ.001) and oxygen saturation (pɘ.01) between SL and NH or HH were observed. There were no...Table 1. Testing Flow Chart with Time Requirements ................................................................4 Table 2. Max VO2 /Running

  12. Natural versus commercial carbohydrate supplementation and endurance running performance

    Directory of Open Access Journals (Sweden)

    Too Brandon W

    2012-06-01

    Full Text Available Abstract Background We examined the metabolic, performance and gastrointestinal (GI effects of supplementation with a natural food product (raisins compared to a commercial product (sport chews. Methods Eleven male (29.3 ± 7.9 yrs; mean and SD runners completed three randomized trials (raisins, chews and water only separated by seven days. Each trial consisted of 80-min (75%VO2max treadmill running followed by a 5-km time trial (TT. Heart rate (HR, respiratory exchange ratio (RER, blood lactate, serum free fatty acids (FFA, glycerol and insulin, plasma glucose and creatine kinase, GI symptoms and rating of perceived exertion (RPE were recorded every 20-min. We employed a within-subject two-way analysis of variance (ANOVA for repeated measures with a Fisher’s post hoc analysis to determine significant differences. Results VO2, HR, lactate, glycerol and RPE did not differ due to treatment. Average plasma glucose was maintained at resting levels (5.3 ± 0.4 mmol·L-1 during the sub-maximal exercise bout (5.9 ± 0.6, 5.7 ± 0.6 and 5.5 ± 0.5 mmol·L-1 for chews, raisins and water respectively, and was significantly higher with chews than water only. RER and % of non-protein macronutrient oxidation derived from carbohydrate was highest with chews, followed by raisins and water was the lowest (74.4 ± 6.4, 70.0 ± 7.0 and 65.1 ± 8.7% for chews, raisins and water respectively during the sub-maximal exercise period. Serum FFA was higher in the water treatment versus both raisins and chews at 80 min of sub-maximal exercise. Serum insulin was higher with the chews than both raisins and water (5.1 ± 2.0, 3.1 ± 0.8, 1.9 ± 0.6 uU·ml-1 for chews, raisins and water respectively. Plasma creatine kinase, corrected for baseline values, for the last 40 min of the sub-maximal exercise bout, was higher with raisins compared to other treatments. The TT was faster for both carbohydrate supplements (20.6

  13. A valid and reproducible protocol for testing maximal oxygen uptake in rabbits.

    Science.gov (United States)

    Gaustad, Svein Erik; Rolim, Natale; Wisløff, Ulrik

    2010-02-01

    Physiological studies of long-term cardiovascular adaptation to exercise require adequate testing procedures to quantify the outcome. Such test procedures are well established in rats and mice. However, the use of these species may have limitations, and to study several physiological parameters mimicking 'the human adaptation' larger animal models may be preferable. Here, we established a valid and reproducible exercise test protocol for measuring maximal oxygen uptake (VO2max) in rabbits. The VO2max protocol was studied in six adult female New Zealand White rabbits running on a treadmill at inclinations ranging from 0 to 20 degrees. VO2max was reached at all inclinations indicating that the rabbits reach exhaustion independent of inclination. Average VO2max for test and retest were 35.1+/-4.2 and 35.8+/-4.0 ml/kg per min, respectively. Oxygen uptake and heart rate increased linearly with increased running speed. Average running speed at VO2max was 0.51+/-0.09 m/s, and there was an increase oxygen pulse up to the intensity corresponding to VO2max, where it leveled off and declined. This study shows that rabbit is a suitable species for studying responses to training and could be of great importance for showing novel cellular cardiac adaptations to training.

  14. Determination of Aerobic Power Through a Specific Test for Taekwondo - A Predictive Equation Model.

    Science.gov (United States)

    Rocha, Fernando P S; Louro, Hugo; Matias, Ricardo; Brito, João; Costa, Aldo M

    2016-12-01

    Our aim was to verify the concurrent validity of a maximal taekwondo specific test (TST) to predict VO2max through an explanatory model. Seventeen elite male taekwondo athletes (age: 17.59 ± 4.34 years; body height: 1.72 ± 6.5 m; body mass: 61.3 ± 8.7 kg) performed two graded maximal exercise tests on different days: a 20 m multistage shuttle run test (SRT) and an incremental TST. We recorded test time, VO2max, ventilation, a heart rate and time to exhaustion. Significant differences were found between observed and estimated VO2max values [F (2, 16) = 5.77, p taekwondo TST (r = 0.74, p = 0.001). Our results suggest that an incremental specific test estimates VO2max of elite taekwondo athletes with acceptable concurrent validity.

  15. Aging, Fitness, and Marathon Times in a 91 Year-old Man Who Competed in 627 Marathons.

    Science.gov (United States)

    Addison, Odessa; Steinbrenner, Gregory; Goldberg, Andrew P; Katzel, Leslie I

    Aging is associated with a decline in maximal aerobic capacity (VO2max) that may be attenuated by chronic endurance exercise. This case study chronicles the changes in marathon times in a 91 year old man who completed 627 marathons and 117 ultramarathons over 42 years. He began running marathons at age 48. His yearly best times remained fairly constant at ~240 minutes from age 50 - 64 years and then gradually rose to about 260 minutes in his early seventies followed by a curvilinear deterioration as he approached his ninth decade. His times plateaued at ~ 600 minutes in his late eighties. Between ages 68 and 89 his VO2max declined from 43 to 20 ml/kg/min. His marathon times were highly correlated with his VO2max (r(2)=0.87). The decline in marathons times and VO2max may reflect the contributions of biological aging, changes in exercise training volume and intensity, injuries, and comorbid disease.

  16. Myocardial adaptation to high-intensity (interval) training in previously untrained men with a longitudinal cardiovascular magnetic resonance imaging study (Running Study and Heart Trial).

    Science.gov (United States)

    Scharf, Michael; Schmid, Axel; Kemmler, Wolfgang; von Stengel, Simon; May, Matthias S; Wuest, Wolfgang; Achenbach, Stephan; Uder, Michael; Lell, Michael M

    2015-04-01

    To prospectively evaluate whether short-term high-intensity (interval) training (HI(I)T) induces detectable morphological cardiac changes in previously untrained men in cardiovascular magnetic resonance imaging. Eighty-four untrained volunteers were randomly assigned to a HI(I)T group (n=42; 44.1±4.7 years) or an inactive control group (n=42; 42.3±5.6 years). HI(I)T focused on interval runs (intensity: 95%-105% of individually calculated heart rate at the anaerobic threshold). Before and after 16 weeks, all subjects underwent physiological examination, stepwise treadmill test with blood lactate analysis, and contrast-enhanced cardiovascular magnetic resonance imaging (cine, tagging, and delayed enhancement). Indexed left ventricular (LV) and right ventricular (RV) volume (LV, 77.1±8.5-83.9±8.6; RV, 80.5±8.5-86.6±8.1) and mass (LV, 58.2±6.4-63.4±8.1; RV, 14.8±1.7-16.1±2.1) significantly increased with HI(I)T. Changes in LV and RV morphological parameters with HI(I)T were highly correlated with an increase in maximal aerobic capacity (VO2max) and a decrease in blood lactate concentration at the anaerobic threshold. Mean LV and RV remodeling index of HI(I)T group did not alter with training (0.76 ±0.09 and 0.24±0.10 g/mL, respectively [P=0.97 and P=0.72]), indicating balanced cardiac adaptation. Myocardial circumferential strain decreased after HI(I)T within all 6 basal segments (anteroseptal, P=0.01 and anterolateral, PHeart Association, Inc.

  17. The effects of a systematic increase in relative humidity on thermoregulatory and circulatory responses during prolonged running exercise in the heat.

    Science.gov (United States)

    Che Muhamed, Ahmad Munir; Atkins, Kerry; Stannard, Stephen R; Mündel, Toby; Thompson, Martin William

    2016-01-01

    This study examined the thermoregulatory and circulatory responses, and exercise performance of trained distance runners during exercise in the heat (31°C) at varying relative humidity (RH). In a randomized order, 11 trained male distance runners performed 5 60 min steady-state runs at a speed eliciting 70% of VO2max in RH of 23, 43, 52, 61 and 71%. This was followed immediately with an incremental exercise test to volitional exhaustion. Core (Tre) and mean skin temperature (T¯sk), cardiac output (Q), heart rate (HR), and stroke volume (SV) were recorded at regular intervals. A significant (P = 0.003) main effect was detected for RH on mean body temperature (Tb), with a significantly higher Tb detected during steady-state exercise in the 61 and 71% RH compared to that in the 23% RH. During the steady-state exercise, no differences were detected in whole body sweat loss (P = 0.183). However, a significant main effect of RH was observed for HR and SV (P = 0.001 and 0.006, respectively) but not Q (P = 0.156). The time to exhaustion of the incremental exercise test was significantly reduced at 61 and 71% RH compared with 23% RH (P = 0.045 and 0.005, respectively). Despite an increase in dry heat loss, a greater thermoregulatory and circulatory stress was evident during steady-state exercise at 61 and 71% RH. This ultimately limits the capacity to perform the subsequent incremental exercise to exhaustion. This study highlighted that in a warm environment, the range of the prescriptive zone progressively narrows as RH increases.

  18. The effects of a systematic increase in relative humidity on thermoregulatory and circulatory responses during prolonged running exercise in the heat

    Science.gov (United States)

    Che Muhamed, Ahmad Munir; Atkins, Kerry; Stannard, Stephen R.; Mündel, Toby; Thompson, Martin William

    2016-01-01

    ABSTRACT This study examined the thermoregulatory and circulatory responses, and exercise performance of trained distance runners during exercise in the heat (31°C) at varying relative humidity (RH). In a randomized order, 11 trained male distance runners performed 5 60 min steady-state runs at a speed eliciting 70% of VO2max in RH of 23, 43, 52, 61 and 71%. This was followed immediately with an incremental exercise test to volitional exhaustion. Core (Tre) and mean skin temperature (T¯sk), cardiac output (Q), heart rate (HR), and stroke volume (SV) were recorded at regular intervals. A significant (P = 0.003) main effect was detected for RH on mean body temperature (Tb), with a significantly higher Tb detected during steady-state exercise in the 61 and 71% RH compared to that in the 23% RH. During the steady-state exercise, no differences were detected in whole body sweat loss (P = 0.183). However, a significant main effect of RH was observed for HR and SV (P = 0.001 and 0.006, respectively) but not Q (P = 0.156). The time to exhaustion of the incremental exercise test was significantly reduced at 61 and 71% RH compared with 23% RH (P = 0.045 and 0.005, respectively). Despite an increase in dry heat loss, a greater thermoregulatory and circulatory stress was evident during steady-state exercise at 61 and 71% RH. This ultimately limits the capacity to perform the subsequent incremental exercise to exhaustion. This study highlighted that in a warm environment, the range of the prescriptive zone progressively narrows as RH increases.

  19. Ecologically Valid Carbohydrate Intake during Soccer-Specific Exercise Does Not Affect Running Performance in a Fed State

    Directory of Open Access Journals (Sweden)

    Mark P. Funnell

    2017-01-01

    Full Text Available This study assessed the effect of carbohydrate intake on self-selected soccer-specific running performance. Sixteen male soccer players (age 23 ± 4 years; body mass 76.9 ± 7.2 kg; predicted VO2max = 54.2 ± 2.9 mL∙kg−1∙min−1; soccer experience 13 ± 4 years completed a progressive multistage fitness test, familiarisation trial and two experimental trials, involving a modified version of the Loughborough Intermittent Shuttle Test (LIST to simulate a soccer match in a fed state. Subjects completed six 15 min blocks (two halves of 45 min of intermittent shuttle running, with a 15-min half-time. Blocks 3 and 6, allowed self-selection of running speeds and sprint times, were assessed throughout. Subjects consumed 250 mL of either a 12% carbohydrate solution (CHO or a non-caloric taste matched placebo (PLA before and at half-time of the LIST. Sprint times were not different between trials (CHO 2.71 ± 0.15 s, PLA 2.70 ± 0.14 s; p = 0.202. Total distance covered in self-selected blocks (block 3: CHO 2.07 ± 0.06 km; PLA 2.09 ± 0.08 km; block 6: CHO 2.04 ± 0.09 km; PLA 2.06 ± 0.08 km; p = 0.122 was not different between trials. There was no difference between trials for distance covered (p ≥ 0.297 or mean speed (p ≥ 0.172 for jogging or cruising. Blood glucose concentration was greater (p < 0.001 at the end of half-time during the CHO trial. In conclusion, consumption of 250 mL of 12% CHO solution before and at half-time of a simulated soccer match does not affect self-selected running or sprint performance in a fed state.

  20. Ecologically Valid Carbohydrate Intake during Soccer-Specific Exercise Does Not Affect Running Performance in a Fed State

    Science.gov (United States)

    Funnell, Mark P.; Dykes, Nick R.; Owen, Elliot J.; Mears, Stephen A.; Rollo, Ian; James, Lewis J.

    2017-01-01

    This study assessed the effect of carbohydrate intake on self-selected soccer-specific running performance. Sixteen male soccer players (age 23 ± 4 years; body mass 76.9 ± 7.2 kg; predicted VO2max = 54.2 ± 2.9 mL∙kg−1∙min−1; soccer experience 13 ± 4 years) completed a progressive multistage fitness test, familiarisation trial and two experimental trials, involving a modified version of the Loughborough Intermittent Shuttle Test (LIST) to simulate a soccer match in a fed state. Subjects completed six 15 min blocks (two halves of 45 min) of intermittent shuttle running, with a 15-min half-time. Blocks 3 and 6, allowed self-selection of running speeds and sprint times, were assessed throughout. Subjects consumed 250 mL of either a 12% carbohydrate solution (CHO) or a non-caloric taste matched placebo (PLA) before and at half-time of the LIST. Sprint times were not different between trials (CHO 2.71 ± 0.15 s, PLA 2.70 ± 0.14 s; p = 0.202). Total distance covered in self-selected blocks (block 3: CHO 2.07 ± 0.06 km; PLA 2.09 ± 0.08 km; block 6: CHO 2.04 ± 0.09 km; PLA 2.06 ± 0.08 km; p = 0.122) was not different between trials. There was no difference between trials for distance covered (p ≥ 0.297) or mean speed (p ≥ 0.172) for jogging or cruising. Blood glucose concentration was greater (p < 0.001) at the end of half-time during the CHO trial. In conclusion, consumption of 250 mL of 12% CHO solution before and at half-time of a simulated soccer match does not affect self-selected running or sprint performance in a fed state. PMID:28067762

  1. The effects of a pre-workout supplement containing caffeine, creatine, and amino acids during three weeks of high-intensity exercise on aerobic and anaerobic performance.

    Science.gov (United States)

    Smith, Abbie E; Fukuda, David H; Kendall, Kristina L; Stout, Jeffrey R

    2010-02-15

    A randomized, single-blinded, placebo-controlled, parallel design study was used to examine the effects of a pre-workout supplement combined with three weeks of high-intensity interval training (HIIT) on aerobic and anaerobic running performance, training volume, and body composition. Twenty-four moderately-trained recreational athletes (mean +/- SD age = 21.1 +/- 1.9 yrs; stature = 172.2 +/- 8.7 cm; body mass = 66.2 +/- 11.8 kg, VO2max = 3.21 +/- 0.85 l.min-1, percent body fat = 19.0 +/- 7.1%) were assigned to either the active supplement (GT, n = 13) or placebo (PL, n = 11) group. The active supplement (Game Time(R), Corr-Jensen Laboratories Inc., Aurora, CO) was 18 g of powder, 40 kcals, and consisted of a proprietary blend including whey protein, cordyceps sinensis, creatine, citrulline, ginseng, and caffeine. The PL was also 18 g of powder, 40 kcals, and consisted of only maltodextrin, natural and artificial flavors and colors. Thirty minutes prior to all testing and training sessions, participants consumed their respective supplements mixed with 8-10 oz of water. Both groups participated in a three-week HIIT program three days per week, and testing was conducted before and after the training. Cardiovascular fitness (VO2max) was assessed using open circuit spirometry (Parvo-Medics TrueOne(R) 2400 Metabolic Measurement System, Sandy, UT) during graded exercise tests on a treadmill (Woodway, Pro Series, Waukesha, WI). Also, four high-speed runs to exhaustion were conducted at 110, 105, 100, and 90% of the treadmill velocity recorded during VO2max, and the distances achieved were plotted over the times-to-exhaustion. Linear regression was used to determine the slopes (critical velocity, CV) and y-intercepts (anaerobic running capacity, ARC) of these relationships to assess aerobic and anaerobic performances, respectively. Training volumes were tracked by summing the distances achieved during each training session for each subject. Percent body fat (%BF) and lean

  2. The effects of a pre-workout supplement containing caffeine, creatine, and amino acids during three weeks of high-intensity exercise on aerobic and anaerobic performance

    Directory of Open Access Journals (Sweden)

    Kendall Kristina L

    2010-02-01

    Full Text Available Abstract Background A randomized, single-blinded, placebo-controlled, parallel design study was used to examine the effects of a pre-workout supplement combined with three weeks of high-intensity interval training (HIIT on aerobic and anaerobic running performance, training volume, and body composition. Methods Twenty-four moderately-trained recreational athletes (mean ± SD age = 21.1 ± 1.9 yrs; stature = 172.2 ± 8.7 cm; body mass = 66.2 ± 11.8 kg, VO2max = 3.21 ± 0.85 l·min-1, percent body fat = 19.0 ± 7.1% were assigned to either the active supplement (GT, n = 13 or placebo (PL, n = 11 group. The active supplement (Game Time®, Corr-Jensen Laboratories Inc., Aurora, CO was 18 g of powder, 40 kcals, and consisted of a proprietary blend including whey protein, cordyceps sinensis, creatine, citrulline, ginseng, and caffeine. The PL was also 18 g of powder, 40 kcals, and consisted of only maltodextrin, natural and artificial flavors and colors. Thirty minutes prior to all testing and training sessions, participants consumed their respective supplements mixed with 8-10 oz of water. Both groups participated in a three-week HIIT program three days per week, and testing was conducted before and after the training. Cardiovascular fitness (VO2max was assessed using open circuit spirometry (Parvo-Medics TrueOne® 2400 Metabolic Measurement System, Sandy, UT during graded exercise tests on a treadmill (Woodway, Pro Series, Waukesha, WI. Also, four high-speed runs to exhaustion were conducted at 110, 105, 100, and 90% of the treadmill velocity recorded during VO2max, and the distances achieved were plotted over the times-to-exhaustion. Linear regression was used to determine the slopes (critical velocity, CV and y-intercepts (anaerobic running capacity, ARC of these relationships to assess aerobic and anaerobic performances, respectively. Training volumes were tracked by summing the distances achieved during each training session for each subject

  3. Association of Occupational and Leisure-Time Physical Activity with Aerobic Capacity in a Working Population

    Science.gov (United States)

    Mundwiler, Jonas; Schüpbach, Ulla; Dieterle, Thomas; Leuppi, Jörg Daniel; Schmidt-Trucksäss, Arno; Wolfer, David Paul; Miedinger, David; Brighenti-Zogg, Stefanie

    2017-01-01

    Introduction Objective data on the association of maximal aerobic capacity (VO2max) with work related physical activity are sparse. Thus, it is not clear whether occupational physical activity (OPA) contributes to an increase of VO2max. This study examined the association of VO2max with work and non-work related physical activity in a Swiss working population. Methods In this cross-sectional study, a total of 337 healthy and full-time employed adults were recruited. Demographic data, height, weight and BMI were recorded in all subjects. Participants were classified into nine occupational categories (ISCO-88) and merged into three groups with low, moderate, and high OPA. Physical activity was objectively measured by the SenseWear Mini Armband on seven consecutive days (23 hours per day). Participants were regarded as sufficiently active when accumulating ≥30 min of moderate-to-vigorous physical activity per day. VO2max was evaluated using the multistage 20-meter shuttle run test. Results Data of 303 participants were considered for analysis (63% male, age 33 yrs, SD 12). Multiple linear regression analysis (adjusted R2 = 0.69) revealed significant positive associations of VO2max with leisure-time physical activity (LTPA) at vigorous intensity (β = 0.212) and sufficient moderate-to-vigorous physical activity (β = 0.100) on workdays. Female gender (β = -0.622), age (β = -0.264), BMI (β = -0.220), the ratio of maximum to resting heart rate (β = 0.192), occupational group (low vs. high OPA, β = -0.141), and smoking (β = -0.133) were also identified as independent predictors of VO2max. Conclusions The present results suggest that VO2max is positively associated with LTPA, but not with OPA on workdays. This finding emphasizes the need for employees to engage in sufficient high-intensity physical activity in recreation for maintaining or improving VO2max with regard to health benefits. PMID:28045939

  4. Predicting functional capacity during treadmill testing independent of exercise protocol.

    Science.gov (United States)

    Foster, C; Crowe, A J; Daines, E; Dumit, M; Green, M A; Lettau, S; Thompson, N N; Weymier, J

    1996-06-01

    Clinically useful estimates of VO2max from treadmill tests (GXT) may be made using protocol-specific equations. In many cases, GXT may proceed more effectively if the clinician is free to adjust speed and grade independent of a specific protocol. We sought to determine whether VO2max could be predicted from the estimated steady-state VO2 of the terminal exercise stage. Seventy clinically stable individuals performed GXT with direct measurement of VO2. Exercise was incremented each minute to optimize clinical examination. Measured VO2max was compared to the estimated steady-state VO2 of the terminal stage based on ACSM equations. Equations for walking or running were used based on the patient's observed method of ambulation. The measured VO2max was always less than the ACSM estimate, with a regular relationship between measured and estimated VO2max. No handrail support: VO2max = 0.869.ACSM -0.07; R2 = 0.955, SEE = 4.8 ml.min-1.kg-1 (N = 30). With handrail support: VO2max = 0.694.ACSM + 3.33; R2 = 0.833, SEE = 4.4 ml.min-1.kg-1 (N = 40). The equations were cross-validated with 20 patients. The correlation between predicted and observed values was r = 0.98 and 0.97 without and with handrail support, respectively. The mean absolute prediction error (3.1 and 4.1 ml.min-1.kg-1) were similar to protocol-specific equations. We conclude that VO2max can be predicted independent of treadmill protocol with approximately the same error as protocol-specific equations.

  5. A cycle ergometer test of maximal aerobic power.

    Science.gov (United States)

    Myles, W S; Toft, R J

    1982-01-01

    An indirect test of maximal aerobic power (IMAP) was evaluated in 31 healthy male subjects by comparing it with a direct treadmill measurement of maximal aerobic power (VO2 max), with the prediction of VO2 max from heart rate during submaximal exercise on a cycle ergometer using Astrand's nomogram, with the British Army's Basic Fitness Test (BFT, a 2.4 km run performed in boots and trousers), and with a test of maximum anaerobic power. For the IMAP test, subjects pedalled on a cycle ergometer at 75 revs X min-1. The workload was 37.5 watts for the first minute, and was increased by 37.5 watts every minute until the subject could not continue. Time to exhaustion was recorded. Predicted VO2 max and times for BFT and IMAP correlated significantly (p less than 0.001) with the direct VO2 max: r = 0.70, r = 0.67 and r = 0.79 respectively. The correlation between direct VO2 max and the maximum anaerobic power test was significant (p less than 0.05) but lower, r = 0.44. Although lactate levels after direct VO2 max determination were significantly higher than those after the IMAP test, maximum heart rates were not significantly different. Submaximal VO2 values measured during the IMAP test yielded a regression equation relating VO2 and pedalling time. When individual values for direct and predicted VO2 max and times for BFT and IMAP were compared with equivalent standards, the percentages of subjects able to exceed the standard were 100, 65, 87, and 87 respectively. These data demonstrate that the IMAP test provides a valid estimate of VO2 max and indicate that it may be a practical test for establishing that an individual meets a minimum standard.

  6. Aerobic fitness and somatic growth in adolescents: a cross sectional investigation in a high school context.

    Science.gov (United States)

    Grassi, G P; Turci, M; Sforza, C

    2006-09-01

    A cross-sectional investigation to study the relations between aerobic fitness and somatic growth of Italian adolescents within a school context. The Léger and Lambert 20-m shuttle run test scores were used to estimate the oxygen uptake (VO2max) of 290 high school adolescent students aged 14-18 years. Descriptive statistics of body mass, standing height, body mass index (BMI) and of predicted VO2max were calculated within age and sex group. Body mass and standing height were significantly larger in males than in females, and significantly increased with age (P VO2max was significantly influenced by sex and age. The age-related decrement in VO2max was larger in females than in males (P = 0.001). Predicted VO2max was significantly related to BMI (males: r = -0.41; females: r = -0.336) and to body mass (females: r = -0.34; males: r = -0.352). A negative relationship between BMI and VO2max was found also in the overweight adolescents. In both sexes, aerobic fitness declined with age. The decline was particularly evident in females. Low-cost methods to detect the nutritional level and aerobic performance of adolescents should be encouraged at school.

  7. Running Linux

    CERN Document Server

    Dalheimer, Matthias Kalle

    2006-01-01

    The fifth edition of Running Linux is greatly expanded, reflecting the maturity of the operating system and the teeming wealth of software available for it. Hot consumer topics such as audio and video playback applications, groupware functionality, and spam filtering are covered, along with the basics in configuration and management that always made the book popular.

  8. RUN COORDINATION

    CERN Multimedia

    C. Delaere

    2013-01-01

    Since the LHC ceased operations in February, a lot has been going on at Point 5, and Run Coordination continues to monitor closely the advance of maintenance and upgrade activities. In the last months, the Pixel detector was extracted and is now stored in the pixel lab in SX5; the beam pipe has been removed and ME1/1 removal has started. We regained access to the vactank and some work on the RBX of HB has started. Since mid-June, electricity and cooling are back in S1 and S2, allowing us to turn equipment back on, at least during the day. 24/7 shifts are not foreseen in the next weeks, and safety tours are mandatory to keep equipment on overnight, but re-commissioning activities are slowly being resumed. Given the (slight) delays accumulated in LS1, it was decided to merge the two global runs initially foreseen into a single exercise during the week of 4 November 2013. The aim of the global run is to check that we can run (parts of) CMS after several months switched off, with the new VME PCs installed, th...

  9. Repo Runs

    NARCIS (Netherlands)

    Martin, A.; Skeie, D.; von Thadden, E.L.

    2010-01-01

    This paper develops a model of financial institutions that borrow short- term and invest into long-term marketable assets. Because these financial intermediaries perform maturity transformation, they are subject to runs. We endogenize the profits of the intermediary and derive distinct liquidity and

  10. Running Club

    CERN Multimedia

    Running Club

    2011-01-01

    The cross country running season has started well this autumn with two events: the traditional CERN Road Race organized by the Running Club, which took place on Tuesday 5th October, followed by the ‘Cross Interentreprises’, a team event at the Evaux Sports Center, which took place on Saturday 8th October. The participation at the CERN Road Race was slightly down on last year, with 65 runners, however the participants maintained the tradition of a competitive yet friendly atmosphere. An ample supply of refreshments before the prize giving was appreciated by all after the race. Many thanks to all the runners and volunteers who ensured another successful race. The results can be found here: https://espace.cern.ch/Running-Club/default.aspx CERN participated successfully at the cross interentreprises with very good results. The teams succeeded in obtaining 2nd and 6th place in the Mens category, and 2nd place in the Mixed category. Congratulations to all. See results here: http://www.c...

  11. RUN COORDINATION

    CERN Multimedia

    M. Chamizo

    2012-01-01

      On 17th January, as soon as the services were restored after the technical stop, sub-systems started powering on. Since then, we have been running 24/7 with reduced shift crew — Shift Leader and DCS shifter — to allow sub-detectors to perform calibration, noise studies, test software upgrades, etc. On 15th and 16th February, we had the first Mid-Week Global Run (MWGR) with the participation of most sub-systems. The aim was to bring CMS back to operation and to ensure that we could run after the winter shutdown. All sub-systems participated in the readout and the trigger was provided by a fraction of the muon systems (CSC and the central RPC wheel). The calorimeter triggers were not available due to work on the optical link system. Initial checks of different distributions from Pixels, Strips, and CSC confirmed things look all right (signal/noise, number of tracks, phi distribution…). High-rate tests were done to test the new CSC firmware to cure the low efficiency ...

  12. RUN COORDINATION

    CERN Multimedia

    Christophe Delaere

    2013-01-01

    The focus of Run Coordination during LS1 is to monitor closely the advance of maintenance and upgrade activities, to smooth interactions between subsystems and to ensure that all are ready in time to resume operations in 2015 with a fully calibrated and understood detector. After electricity and cooling were restored to all equipment, at about the time of the last CMS week, recommissioning activities were resumed for all subsystems. On 7 October, DCS shifts began 24/7 to allow subsystems to remain on to facilitate operations. That culminated with the Global Run in November (GriN), which   took place as scheduled during the week of 4 November. The GriN has been the first centrally managed operation since the beginning of LS1, and involved all subdetectors but the Pixel Tracker presently in a lab upstairs. All nights were therefore dedicated to long stable runs with as many subdetectors as possible. Among the many achievements in that week, three items may be highlighted. First, the Strip...

  13. Running Patterns of Highly Skilled Distance Runners.

    Science.gov (United States)

    Dunetts, Michael J.; Dillman, Charles J.

    The biomechanical elements inherent in the running styles of Olympic-level athletes were examined in order to obtain a range of parameter values for specific running velocities. Forty-eight athletes participated in middle and long distance running events that were filmed and later analyzed to determine the relationship between the physical…

  14. RUN COORDINATION

    CERN Multimedia

    G. Rakness.

    2013-01-01

    After three years of running, in February 2013 the era of sub-10-TeV LHC collisions drew to an end. Recall, the 2012 run had been extended by about three months to achieve the full complement of high-energy and heavy-ion physics goals prior to the start of Long Shutdown 1 (LS1), which is now underway. The LHC performance during these exciting years was excellent, delivering a total of 23.3 fb–1 of proton-proton collisions at a centre-of-mass energy of 8 TeV, 6.2 fb–1 at 7 TeV, and 5.5 pb–1 at 2.76 TeV. They also delivered 170 μb–1 lead-lead collisions at 2.76 TeV/nucleon and 32 nb–1 proton-lead collisions at 5 TeV/nucleon. During these years the CMS operations teams and shift crews made tremendous strides to commission the detector, repeatedly stepping up to meet the challenges at every increase of instantaneous luminosity and energy. Although it does not fully cover the achievements of the teams, a way to quantify their success is the fact that that...

  15. The effects of a multi-ingredient supplement on markers of muscle damage and inflammation following downhill running in females.

    Science.gov (United States)

    Köhne, Jessica L; Ormsbee, Michael J; McKune, Andrew J

    2016-01-01

    The effects of a multi-ingredient performance supplement (MIPS) on markers of inflammation and muscle damage, perceived soreness and lower limb performance are unknown in endurance-trained female athletes. The purpose of this study was to determine the impact of MIPS (NO-Shotgun®) pre-loaded 4 weeks prior to a single-bout of downhill running (DHR) on hsC-Reactive Protein (hsCRP), interleukin (IL)-6, creatine kinase (CK), muscle soreness, lower limb circumferences and performance. Trained female runners (n = 8; 29 ± 5.9 years) (VO2max: ≥ 50 ml(-1).kg(-1).min(-1), midfollicular phase (7-11 days post-menses) were randomly assigned in a double-blind manner into two groups: MIPS (n = 4) ingested one serving of NO Shotgun daily for 28 days prior to DHR and 30 min prior to all post-testing visits; Control (CON) (n = 4) consumed an isocaloric maltodextrin placebo in an identical manner to MIPS. hsCRP, IL-6, CK, perceived soreness, limb circumferences, and performance measures (flexibility, squat jump peak power) were tested on 5 occasions; immediately before (PRE), immediately post-DHR, 24, 48 and 72 h post-DHR. There were main effects of time for CK (p = 0.05), pain pressure threshold (right tibialis anterior (p = 0.010), right biceps femoris (p = 0.01), and left iliotibial band (ITB) (p = 0.05) across all time points), and maximum squat jump power (p = 0.04). Compared with 24 h post-DHR, maximum squat jump power was significantly lower at 48 h post-DHR (p = 0.05). Lower body perceived soreness was significantly increased at 24 h (p = 0.02) and baseline to 48 h (p = 0.02) post DHR. IL-6 peaked immediately post-DHR (p = 0.03) and hsCRP peaked at 24 h post-DHR (p = 0.06). Calculation of effect sizes indicated a moderate attenuation of hsCRP in MIPS at 72 h post-DHR. Consumption of MIPS for 4 weeks prior to a single bout of DHR attenuated inflammation three days post, but did not affect perceived

  16. How to run 100 meters?

    CERN Document Server

    Aftalion, Amandine

    2016-01-01

    The aim of this paper is to bring a mathematical justification to the optimal way of organizing one's effort when running. It is well known from physiologists that all running exercises of duration less than 3mn are run with a strong initial acceleration and a decelerating end; on the contrary, long races are run with a final sprint. This can be explained using a mathematical model describing the evolution of the velocity, the anaerobic energy, and the propulsive force: a system of ordinary differential equations, based on Newton's second law and energy conservation, is coupled to the condition of optimizing the time to run a fixed distance. We show that the monotony of the velocity curve vs time is the opposite of that of the oxygen uptake (V O2) vs time. Since the oxygen uptake is monotone increasing for a short run, we prove that the velocity is exponentially increasing to its maximum and then decreasing. For longer races, the oxygen uptake has an increasing start and a decreasing end and this accounts for...

  17. EFFECT OF IMMEDIATE AND DELAYED COLD WATER IMMERSION AFTER A HIGH INTENSITY EXERCISE SESSION ON SUBSEQUENT RUN PERFORMANCE

    Directory of Open Access Journals (Sweden)

    Ned Brophy-Williams

    2011-12-01

    Full Text Available The purpose of the study was to determine the effects of cold water immersion (CWI performed immediately or 3 h after a high intensity interval exercise session (HIIS on next-day exercise performance. Eight male athletes performed three HIIS at 90%VO2max velocity followed by either a passive recovery (CON, CWI performed immediately post-exercise (CWI(0 or CWI performed 3 h post-exercise (CWI(3. Recovery trials were performed in a counter balanced manner. Participants then returned 24 h later and completed a muscle soreness and a totally quality recovery perception (TQRP questionnaire, which was then followed by the Yoyo Intermittent Recovery Test [level 1] (YRT. Venous blood samples were collected pre-HIIS and pre-YRT to determine C-Reactive Protein (CRP levels. Significantly more shuttles were performed during the YRT following CWI(0 compared to the CON trial (p=0.017, ES = 0. 8, while differences between the CWI(3 and the CON trials approached significance (p = 0.058, ES = 0.5. Performance on the YRT between the CWI(0 and CWI(3 trials were similar (p = 0.147, ES = 0. 3. Qualitative analyses demonstrated a 98% and 92% likely beneficial effect of CWI(0 and CWI(3 on next day performance, compared to CON, respectively, while CWI(0 resulted in a 79% likely benefit when compared to CWI(3. CRP values were significantly lower pre-YRT, compared to baseline, following CWI(0 (p = 0.0.36 and CWI(3 (p = 0.045, but were similar for CON (p = 0.157. Muscle soreness scores were similar between trials (p = 1.10, while TQRP scores were significantly lower for CON compared to CWI(0 (p = 0.002 and CWI(3 (p = 0.024. Immediate CWI resulted in superior next-day YRT performance compared to CON, while delayed (3 h CWI was also likely to be beneficial. Qualitative analyses suggested that CWI(0 resulted in better performance than CWI(3. These results are important for athletes who do not have immediate access to CWI following exercise

  18. Effect of immediate and delayed cold water immersion after a high intensity exercise session on subsequent run performance.

    Science.gov (United States)

    Brophy-Williams, Ned; Landers, Grant; Wallman, Karen

    2011-01-01

    The purpose of the study was to determine the effects of cold water immersion (CWI) performed immediately or 3 h after a high intensity interval exercise session (HIIS) on next-day exercise performance. Eight male athletes performed three HIIS at 90%VO2max velocity followed by either a passive recovery (CON), CWI performed immediately post-exercise (CWI(0)) or CWI performed 3 h post-exercise (CWI(3)). Recovery trials were performed in a counter balanced manner. Participants then returned 24 h later and completed a muscle soreness and a totally quality recovery perception (TQRP) questionnaire, which was then followed by the Yoyo Intermittent Recovery Test [level 1] (YRT). Venous blood samples were collected pre-HIIS and pre-YRT to determine C-Reactive Protein (CRP) levels. Significantly more shuttles were performed during the YRT following CWI(0) compared to the CON trial (p=0.017, ES = 0. 8), while differences between the CWI(3) and the CON trials approached significance (p = 0.058, ES = 0.5). Performance on the YRT between the CWI(0) and CWI(3) trials were similar (p = 0.147, ES = 0. 3). Qualitative analyses demonstrated a 98% and 92% likely beneficial effect of CWI(0) and CWI(3) on next day performance, compared to CON, respectively, while CWI(0) resulted in a 79% likely benefit when compared to CWI(3). CRP values were significantly lower pre-YRT, compared to baseline, following CWI(0) (p = 0.0.36) and CWI(3) (p = 0.045), but were similar for CON (p = 0.157). Muscle soreness scores were similar between trials (p = 1.10), while TQRP scores were significantly lower for CON compared to CWI(0) (p = 0.002 ) and CWI(3) (p = 0.024). Immediate CWI resulted in superior next-day YRT performance compared to CON, while delayed (3 h) CWI was also likely to be beneficial. Qualitative analyses suggested that CWI(0) resulted in better performance than CWI(3). These results are important for athletes who do not have immediate access to CWI following exercise. Key points

  19. Physiological characteristics of elite prepubertal cross-country runners.

    Science.gov (United States)

    Mayers, N; Gutin, B

    1979-01-01

    Eight elite cross-country runners and eight normally active boys 8--11 years of age were studied. The runners were selected on the basis of success in regional and/or national championships. Two of them had the first to third fastest mile run times for their age groups in the U.S. for three years. Tests included submaximal and maximal treadmill runs, an anaerobic capacity bicycle test, a mile run, and various anthropometric measures. A best career mile run (BCM) was used for comparisons within the running group. At submaximal work levels of 5.6 and 7 mph (124, 161, and 187 meters/min) the values for heart rate (HR) and respiratory exchange ratio (R) were significantly lower for the runners than for the non-runners. The VO2max of the runners (56.6 ml kg min) was significantly higher than that of the non-runners (46.0 ml kg min). For all subjects combined, mile run time was highly correlated with percent VO2max and percent max HR at all submaximal running speeds (r greater than 0.8). The correlation coefficient between mile run time and VO2max was -0.88. Within the running group, however, BCM was unrelated to VO2max but was closely related to percent VO2max at 8 mph (213 meters/min) with 4 = 0.86, and to anaerobic capacity (r = -0.88). There were no significant differences between the groups in age, height, weight, max HR, and percent body fat. Thus the runners had higher aerobic and anaerobic capacities, and greater utilization of fat as an enrgy sustrate during submaximal work. Within the running group, anaerobic capacity and running economy were closely related to BCM time, whereas VO2max was not.

  20. A program of moderate physical training for Wistar rats based on maximal oxygen consumption.

    Science.gov (United States)

    Leandro, Carol Góis; Levada, Adriana Cristina; Hirabara, Sandro Massao; Manhães-de-Castro, Raul; De-Castro, Célia Barbosa; Curi, Rui; Pithon-Curi, Tânia Cristina

    2007-08-01

    Moderate physical training is often associated with improved cardiorespiratory fitness in athletes and the general population. In animals, studies are designed to investigate basic physiology that could be invasive and uncomfortable for humans. The standardization of an exercise training protocol for rats based on maximal consumption of oxygen (VO(2)max) is needed. This study validated a program of moderate physical training for Wistar rats based on VO(2)max determined once a week. A 10-stage treadmill running test was developed to measure VO(2)max through an indirect, open circuit calorimeter. Thirty male Wistar rats (210-226 g) were randomly assigned to either a nontrained group or a trained group. The animals were evaluated weekly to follow their VO(2)max during 8 weeks of moderate training and to adjust the intensity of the protocol of training. The soleus muscle was removed for determination of citrate synthase activity. Trained animals maintained their values of VO(2)max during a moderate running training and showed a significant less body weight gain. An increase of 42% in citrate synthase activity of the soleus muscle from trained rats was found after the training program. Our study presents a protocol of moderate physical training for Wistar rats based on VO(2)max. Peripheral adaptations such as the values of citrate synthase activity also responded to the moderate training program imposed as observed for VO(2)max. Other studies can use our protocol of moderate training to study the physiologic adaptations underlying this specific intensity of training. It will provide support for study with humans.

  1. Running Club

    CERN Multimedia

    Running Club

    2010-01-01

    The 2010 edition of the annual CERN Road Race will be held on Wednesday 29th September at 18h. The 5.5km race takes place over 3 laps of a 1.8 km circuit in the West Area of the Meyrin site, and is open to everyone working at CERN and their families. There are runners of all speeds, with times ranging from under 17 to over 34 minutes, and the race is run on a handicap basis, by staggering the starting times so that (in theory) all runners finish together. Children (< 15 years) have their own race over 1 lap of 1.8km. As usual, there will be a “best family” challenge (judged on best parent + best child). Trophies are awarded in the usual men’s, women’s and veterans’ categories, and there is a challenge for the best age/performance. Every adult will receive a souvenir prize, financed by a registration fee of 10 CHF. Children enter free (each child will receive a medal). More information, and the online entry form, can be found at http://cern.ch/club...

  2. RUN COORDINATION

    CERN Multimedia

    Christophe Delaere

    2012-01-01

      On Wednesday 14 March, the machine group successfully injected beams into LHC for the first time this year. Within 48 hours they managed to ramp the beams to 4 TeV and proceeded to squeeze to β*=0.6m, settings that are used routinely since then. This brought to an end the CMS Cosmic Run at ~Four Tesla (CRAFT), during which we collected 800k cosmic ray events with a track crossing the central Tracker. That sample has been since then topped up to two million, allowing further refinements of the Tracker Alignment. The LHC started delivering the first collisions on 5 April with two bunches colliding in CMS, giving a pile-up of ~27 interactions per crossing at the beginning of the fill. Since then the machine has increased the number of colliding bunches to reach 1380 bunches and peak instantaneous luminosities around 6.5E33 at the beginning of fills. The average bunch charges reached ~1.5E11 protons per bunch which results in an initial pile-up of ~30 interactions per crossing. During the ...

  3. RUN COORDINATION

    CERN Multimedia

    C. Delaere

    2012-01-01

      With the analysis of the first 5 fb–1 culminating in the announcement of the observation of a new particle with mass of around 126 GeV/c2, the CERN directorate decided to extend the LHC run until February 2013. This adds three months to the original schedule. Since then the LHC has continued to perform extremely well, and the total luminosity delivered so far this year is 22 fb–1. CMS also continues to perform excellently, recording data with efficiency higher than 95% for fills with the magnetic field at nominal value. The highest instantaneous luminosity achieved by LHC to date is 7.6x1033 cm–2s–1, which translates into 35 interactions per crossing. On the CMS side there has been a lot of work to handle these extreme conditions, such as a new DAQ computer farm and trigger menus to handle the pile-up, automation of recovery procedures to minimise the lost luminosity, better training for the shift crews, etc. We did suffer from a couple of infrastructure ...

  4. The effect of performance feedback on cardiorespiratory fitness field tests.

    Science.gov (United States)

    Metsios, G S; Flouris, A D; Koutedakis, Y; Theodorakis, Y

    2006-06-01

    We investigated the effects of performance feedback (PF) on predicting maximal oxygen uptake (VO2 max) using the 20 m Multistage Shuttle Run Test (MST) and 20 m Square Shuttle Test (SST). The agreement between these two field tests in relation to laboratory VO2 max was also examined. Forty healthy males (age: 21.5+/-2.3; BMI: 23.7+/-2.0) randomly performed four indirect VO2 max tests; that is the MST and SST, as well as a modified version of MST (MSTMD) and SST (SSTMD). During MST and SST subjects received PF with respect to both test stage and running pace. In contrast, MSTMD and SSTMD incorporated auditory feedback which solely emitted signals regulating the running pace. Participants also performed a laboratory VO2 max treadmill test (TT). ANOVA demonstrated significant mean predicted VO2 max decrements in both MSTMD (pmax, the '95% limits of agreement' analysis indicated errors equal to 3.6+/-9.6 and 1.4+/-10.3 ml kg-1 min-1 with coefficients of variation of +/-10.0% and +/-10.9%, for MST and MSTMD, respectively. The corresponding '95% limits of agreement' values for SST and SSTMD were 0.1+/-5.0 and -1.1+/-6.1 ml kg-1 min-1 with coefficients of variation of +/-5.4% and +/-6.7%, respectively. It is concluded that the application of PF leads to superior field testing performances.

  5. Energy velocity and group velocity

    Institute of Scientific and Technical Information of China (English)

    陈宇

    1995-01-01

    A new Lagrangian method for studying the relationship between the energy velocity and the group velocity is described. It is proved that under the usual quasistatic electric field, the energy velocity is identical to the group velocity for acoustic waves in anisotropic piezoelectric (or non-piezoelectric) media.

  6. Effects of simulated weightlessness and sympathectomy on maximum VO2 of male rats

    Science.gov (United States)

    Woodman, C. R.; Stump, C. S.; Beaulieu, S. M.; Rahman, Z.; Sebastian, L. A.

    1989-01-01

    The effects of simulated weightlessness (hind-limb suspension) and chemical sympathectomy (by repeated injections with guanethidine sulfate) on the maximum oxygen consumption (VO2 max) of female rats were investigated in rats assigned for 14 days to one of three groups: a head-down hind-limb suspension, a horizontal suspension with hind limbs weight bearing, or the caged control. The VO2 max values were assessed by having rats run on a treadmill enclosed in an airtight chamber. The hind-limb-suspended sympathectomized rats were found to exhibit shorter run times and lower mechanical efficiencies, compared to their presuspension values or the values from saline-injected suspended controls. On the other hand, the suspended sympathectomized rats did not demonstrate a decrease in the VO2 max values that was observed in saline-injected controls.

  7. Comparison of Level and Graded Treadmill Tests to Evaluate Endurance Mountain Runners

    Directory of Open Access Journals (Sweden)

    Pascal Balducci, Michel Clémençon, Baptiste Morel, Géraud Quiniou, Damien Saboul, Christophe A. Hautier

    2016-03-01

    Full Text Available Mountain endurance running has increased in popularity in recent years. Thus the aim of the present study was to determine if maximal oxygen uptake (VO2max and energy cost of running (Cr measured during level and uphill running are associated. Ten high level male endurance mountain runners performed three maximal oxygen uptake tests at three slope conditions (0, 12.5 and 25%. Metabolic data, step frequency (SF and step length (SL were recorded. No significant differences were found in VO2max (63.29 (±3.84, 63.97 (±3.54 and 63.70 (±3.58 mlO2/kg-1/min-1 or associated metabolic data at 0, 12.5 and 25% slope respectively. High intra-individual correlations were found between metabolic data measured in the three conditions. The energy cost of running was significantly different between slopes (0.192 (±0.01, 0.350 (±0.029 and 0.516 (±0.035 mlO2/kg-1/min-1, p < 0.01, 0, 12.5 and 25% respectively. However, Cr0% was not correlated with either Cr25% or Cr12.5% (rs = 0.09 and rs = 0.10, in contrast, Cr25% and Cr12.5% were correlated (rs = 0.78. Step length was positively correlated with speed under the three slope conditions. Step frequency was significantly lower at 25 compared to 12.5 and 0% slope. We found that the maximum aerobic power did not differ between level and graded treadmill tests. However, the increase in Cr on the inclined versus level conditions varied between subjects. None of the measured anthropometric or kinematic variables could explain the higher increase in Cr of some subjects when running uphill. Thus, a short graded (5min at 12.5% running test should be performed at a submaximal velocity (around 40% of level vVO2max to enhance understanding of an endurance runner’s uphill capability.

  8. The application of soccer performance testing protocols to the non-elite player.

    Science.gov (United States)

    Siegler, J; Robergs, R; Weingart, H

    2006-03-01

    The application of performance testing for the evaluation of non-elite soccer players has received little attention. The purpose of this investigation was to use tests developed for elite soccer players to evaluate performance in non-elite soccer players and compare performance test results between elite (literature) and non-elite (data) players. Thirteen male soccer players volunteered to participate. The tests included a treadmill VO2max test, 20 m sprint, vertical jump (VJ), 30 s Wingate cycle ergometer test, the Loughborough Intermittent Shuttle Test (LIST), and 2 20-m multi-stage shuttle runs to exhaustion (fatigue test). Actual VO2max (absolute and relative) scores were correlated with the estimated VO2max scores (fatigue test), 20 m sprint, VJ, and 30 s Wingate using a Pearson's product-moment correlation. A paired t-test was conducted on the fatigue test trials. Non-significant relationships were observed between actual VO2max scores and estimated VO2max from the fatigue test (absolute and relative terms). Non-significant relationships were also observed between peak and average power output (Wingate), 20 m sprint, and VJ. Mean heart rates (HRs) throughout the LIST was 165+/-7 bpm, which represented 88% of HRmax. The results of this study demonstrate that to elicit physiological differences between elite and non-elite players, assessment must include both an aerobic and anaerobic component.

  9. Determination of maximal oxygen consumption of algerian soccer players during preseason

    Directory of Open Access Journals (Sweden)

    DADI ABDELAZIZ

    2011-04-01

    Full Text Available The aim of this study was to assess the cardio-respiratory profile (VO2 max of Algerian soccer players duringpreseason and compare VO2 max by competition level. Materials and Methods.- A total of 45 Algerian soccerplayers participated in the study, of which 22 were second division, 23 third division forwards with an averageage of 23.13 ± 2.46 years; height 180, 67 ± 3, 54 cm; weight 80,35 ± 3,25 kg; body mass index 24,61± 0,38kg/m2. In order to evaluate the VO2 max of players, the 20-m Multi Stage Shuttle Run Test (MST protocol wasused as recommended by (Leger et al., 1988. Results: of the total sample (n=45 with a general average of57,38 ± 1,83 ml/kg/min, in which Second division sample (n=22 with a average of 58,28 ± 1,35 ml/kg/min hadthe highest VO2 max and third division sample (n=23 with a average of 56,53 ± 1,84 ml/kg/min. a statisticallysignificant differences were found (P<0.05 between competition level. Conclusion: Results show that theAlgerian second division football players tested have a normal VO2 max at the beginning of the preseason incomparison with the findings of other studies of international soccer players

  10. The acute 1-week effects of the Zone diet on body composition, blood lipid levels, and performance in recreational endurance athletes.

    Science.gov (United States)

    Jarvis, Mark; McNaughton, Lars; Seddon, Alan; Thompson, Dylan

    2002-02-01

    The aim of this study was to examine the effects of a 7-day Zone diet compared with a normal diet on maximal oxygen uptake (V(O)2 max), running time to exhaustion during endurance performance, and body composition. Eight men, with the following physical characteristics (mean +/- SE), participated in this study: age, 26.1 +/- 1.9 years; height, 178 +/- 1.7 cm; mass, 70.7 +/- 2.1 kg; and V(O)2 max, 54.6 +/- 3.1 ml x kg(-1) x min(-1). All subjects undertook pretesting for V(O)2 max, time to exhaustion (80% V(O)2 max), and body composition (Biostat 1500) before following either the normal diet or the Zone diet for 7 days. These performance trials were performed before and after the dietary period. There was a significant (p diet to 1,994 +/- 438 kcal on the Zone diet. Subjects showed a significant reduction (p diet to 34.11 +/- 7.01 minutes for the Zone diet. In conclusion, the claim of the authors of the Zone diet that performance time and V(O)2 max can be improved was not shown in this 1-week research trial. We would suggest that this is not a nutritional strategy that athletes should use until further work has been conducted.

  11. Factors influencing the diabetes-specific health-related quality of life in children and adolescents with type 1 diabetes mellitus.

    Science.gov (United States)

    Lukács, Andrea; Varga, Beatrix; Kiss-Tóth, Emőke; Soós, Andrea; Barkai, László

    2014-09-01

    This study aimed to investigate the association of the anthropometric, clinical variables and maximal oxygen uptake (Vo2max) with diabetes-specific health-related quality of life (HRQoL) in youths with type 1 diabetes mellitus (T1DM) and to find the predictors of HRQoL and blood glucose control. A total of 239 youths with diabetes (124 boys and 115 girls) were recruited from diabetes-based summer camps. HRQoL assessment was carried out with the Pediatric Quality of Life Inventory 3.0 Diabetes Module (Information Resources Centre, Mapi Research Trust, France); Vo2max was evaluated by conducting the 20-m shuttle run test. Higher Vo2max and the insulin pump therapy were significant predictors of the HRQoL in the multiple regression analysis; other clinical and anthropometric variables had no effect. The better blood glucose control was explained only by the higher Vo2max. The good cardiorespiratory fitness (expressed by Vo2max) has clinical and QoL benefits for paediatric patients with T1DM.

  12. A Regression Equation for the Estimation of Maximum Oxygen Uptake in Nepalese Adult Females

    Science.gov (United States)

    Chatterjee, Pinaki; Banerjee, Alok K; Das, Paulomi; Debnath, Parimal

    2010-01-01

    Purpose Validity of the 20-meter multi stage shuttle run test (20-m MST) has not been studied in Nepalese population. The purpose of this study was to validate the applicability of the 20-m MST in Nepalese adult females. Methods Forty female college students (age range, 20.42 ~24.75 years) from different colleges of Nepal were recruited for the study. Direct estimation of VO2 max comprised treadmill exercise followed by expired gas analysis by scholander micro-gas analyzer whereas VO2 max was indirectly predicted by the 20-m MST. Results The difference between the mean (±SD) VO2 max values of direct measurement (VO2 max = 32.78 +/-2.88 ml/kg/min) and the 20-m MST (SPVO2 max = 32.53 + /-3.36 ml/kg/min) was statistically insignificant (P>0.1). Highly significant correlation (r=0.94, PVO2 max. Limits of agreement analysis also suggest that the 20-m MST can be applied for the studied population. Conclusion The results of limits of agreement analysis suggest that the application of the present form of the 20-m MST may be justified in the studied population. However, for better prediction of VO2 max, a new equation has been computed based on the present data to be used for female college students of Nepal. PMID:22375191

  13. Effects of aerobic fitness on oxygen uptake kinetics in heavy intensity swimming.

    Science.gov (United States)

    Reis, Joana F; Alves, Francisco B; Bruno, Paula M; Vleck, Veronica; Millet, Gregoire P

    2012-05-01

    This study aimed to characterise both the VO2 kinetics within constant heavy-intensity swimming exercise, and to assess the relationships between VO2 kinetics and other parameters of aerobic fitness, in well-trained swimmers. On separate days, 21 male swimmers completed: (1) an incremental swimming test to determine their maximal oxygen uptake (VO2 max), first ventilatory threshold (VT), and the velocity associated with VO2max (vVO(2 max)) and (2) two square-wave transitions from rest to heavy-intensity exercise, to determine their VO2 kinetics. All the tests involved breath-by-breath analysis of freestyle swimming using a swimming snorkel. VO2 kinetics was modelled with two exponential functions. The mean values for the incremental test were 56.0 ± 6.0 ml min(-1) kg(-1), 1.45 ± 0.08 m s(-1); and 42.1 ± 5.7 ml min(-1) kg(-1) for VO2 max, vVO(2 max) and VT, respectively. For the square-wave transition, the time constant of the primary phase (sp) averaged 17.3 ± 5.4 s and the relevant slow component (A'sc) averaged 4.8 ± 2.9 ml min(-1) kg(-1) [representing 8.9% of the end-exercise VO2 (%A'sc)]. sp was correlated with vVO(2 max) (r = -0.55, P = 0.01), but not with either VO2max (r = 0.05, ns) or VT (r = 0.14, ns). The %A' sc did not correlate with either VO2max (r = -0.14, ns) or vVO(2 max) (r = 0.06, ns), but was inversely related with VT (r = -0.61, P VO2 kinetics in heavy-intensity swimming using specific swimming exercise and appropriate methods. As has been demonstrated in cycling, faster VO2 kinetics allow higher aerobic power outputs to be attained. The slow component seems to be reduced in swimmers with higher ventilatory thresholds.

  14. Measurements for improvement of running capacity. : Physiological and biomechanical evaluations

    OpenAIRE

    Gullstrand, Lennart

    2009-01-01

    Introduction: Running is included in a large number of sports and one of the most well investigated modes of locomotion in both physiology and biomechanics. This thesis focuses on how some new methods from both areas may be used to capture running capacity in mid-distance and distance running from laboratory and field recordings. Measurement of running economy is included and defined as oxygen uptake at a given submaximal velocity in a steady-state condition. Running economy...

  15. Reliability, validity and usefulness of 30-15 Intermittent Fitness Test in Female Soccer Players

    Directory of Open Access Journals (Sweden)

    Nedim Čović

    2016-11-01

    Full Text Available PURPOSE: The aim of this study was to examine the reliability, validity and usefulness of the 30-15IFT in competitive female soccer players. METHODS: Seventeen elite female soccer players participated in the study. A within subject test-retest study design was utilized to assess the reliability of the 30-15 intermittent fitness test (IFT. Seven days prior to 30-15IFT, subjects performed a continuous aerobic running test (CT under laboratory conditions to assess the criterion validity of the 30-15IFT. End running velocity (VCT and VIFT, peak heart rate (HRpeak and maximal oxygen consumption (VO2max were collected and/or estimated for both tests. RESULTS: VIFT (ICC = 0.91; CV = 1.8%, HRpeak (ICC = 0.94; CV = 1.2%, and VO2max (ICC = 0.94; CV = 1.6% obtained from the 30-15IFT were all deemed highly reliable (p>0.05. Pearson product moment correlations between the CT and 30-15IFT for VO2max, HRpeak and end running velocity were large (r = 0.67, p=0.013, very large (r = 0.77, p=0.02 and large (r = 0.57, p=0.042, respectively. CONCLUSION: Current findings suggest that the 30 -15IFT is a valid and reliable intermittent aerobic fitness test of elite female soccer players. The findings have also provided practitioners with evidence to support the accurate detection of meaningful individual changes in VIFT of 0.5 km/h (1 stage and HRpeak of 2 bpm. This information may assist coaches in monitoring ‘real’ aerobic fitness changes to better inform training of female intermittent team sport athletes. Lastly, coaches could use the 30-15IFT as a practical alternative to laboratory based assessments to assess and monitor intermittent aerobic fitness changes in their athletes. Keywords: 30-15 intermittent fitness test, aerobic, cardiorespiratory fitness, intermittent activity, soccer, high intensity interval training.

  16. Changes in running economy following downhill running.

    Science.gov (United States)

    Chen, Trevor C; Nosaka, Kazunori; Tu, Jui-Hung

    2007-01-01

    In this study, we examined the time course of changes in running economy following a 30-min downhill (-15%) run at 70% peak aerobic power (VO2peak). Ten young men performed level running at 65, 75, and 85% VO2peak (5 min for each intensity) before, immediately after, and 1 - 5 days after the downhill run, at which times oxygen consumption (VO2), minute ventilation, the respiratory exchange ratio (RER), heart rate, ratings of perceived exertion (RPE), and blood lactate concentration were measured. Stride length, stride frequency, and range of motion of the ankle, knee, and hip joints during the level runs were analysed using high-speed (120-Hz) video images. Downhill running induced reductions (7 - 21%, P run. Oxygen consumption increased (4 - 7%, P stride frequency, as well as reductions in stride length and range of motion of the ankle and knee. The results suggest that changes in running form and compromised muscle function due to muscle damage contribute to the reduction in running economy for 3 days after downhill running.

  17. Physiological and Psychological Characteristics of Successful Combat Controller Trainees

    Science.gov (United States)

    2010-12-01

    heart rate (bpm), maximal respiratory exchange ratio (RER), and run- ning economy (mL.kg-1.min-1). Relative, absolute, and run- ning economy VO2 max ...beats per minute while max RER values ranged from 1.12 to 1.38. Table 3 displays means and standard deviations for the Makoto proactive reaction time

  18. Short and long term effects of the Copenhagen school child intervention study (CoSCIS) on cardiovascular risk factors

    DEFF Research Database (Denmark)

    Bugge, Anna; Hermansen, Bianca El-Naaman; Froberg, Karsten

    13.35 yr in 7th grade). BMI, sum of 4 skinfolds (S4SF) and waist to hip ratio (WHR) were measured. PA was measured using CSA accelerometers for four consecutive days. Aerobic fitness (VO2max) was directly measured during a maximal progressive running test on a treadmill. Fasting intravenous blood...... to CG-boys. There were no differences between groups in VO2max or PA at any time point. Our results suggest that school-based intervention might have an effect on CVD risk factors even without measurable changes in fitness and fatness. Funded by The Danish Heart Foundation and The Denmark...

  19. On factor analysis about the increment of %△ Vo2 max after endurance training%耐力训练后最大摄氧量增量(%△(V)o2max)的因素分析

    Institute of Scientific and Technical Information of China (English)

    卢塞军

    2002-01-01

    根据有关文献资料的统计结果,进一步分析各负荷因素对(V)o2max的影响,揭示(V)o2max增量规律,掌握改善(V)o2max的训练方法和运动处方,为发展耐力素质和科学健身提供研究资料和科学依据.

  20. Specific Intensity for Peaking: Is Race Pace the Best Option?

    Directory of Open Access Journals (Sweden)

    Munoz

    2015-09-01

    Full Text Available Background The peaking period for endurance competition is characterized for a relative increase of the intensity of training, after a longer period of training relatively dominated by lower intensity and higher volume Objectives The present study was designed to compare physiological and 10 km performance effects of high intensity training (HIT versus race pace interval training (RP during peaking for competition in well-trained runners. Patients and Methods 13 athletes took part in the study, they were divided into two groups: HIT and RP. HIT performed short intervals at ~105% of the maximal aerobic velocity (MAV, while RP trained longer intervals at a speed of ~90% of the MAV (a speed approximating 10 km race pace. After 12 weeks of baseline training, the athletes trained for 6 weeks under one of the two peaking regimes. Subjects performed 10 km prior to and after the intervention period. The total load of training was matched between groups during the treatment phase. Subjects completed a graded treadmill running test until volitional exhaustion prior to each 10 km race. MAV was determined as the minimal velocity eliciting maximal oxygen consumption (VO2max. Results Both groups significantly improved their 10 km time (35 minutes 29 seconds ± 1 minutes 41 seconds vs 34 minutes 53 seconds ± 1 minutes 55 seconds, P 0.05. In contrast, running economy decreased significantly after HIT (210 ± 6 ml.Kg-1.km-1 vs 218 ± 9, P < 0.05. Conclusions A 6 week period of training at either 105% of MAV or 90% of MAV yielded similar performance gains in a 10km race performed at ~90% MAV. Therefore, the physiological impact of HIT training seems to be positive for VO2max but negative for running economy.

  1. Can Unshod Running Reduce Running Injuries?

    Science.gov (United States)

    2012-06-08

    quadrupeds run, their internal organs expand and contract like an accordion as they stride when running. As a cheetah strides forward, its lungs expand...and take in air. When the cheetah compresses its stride, the lungs are collapsed and the cheetah breathes out. This take-a-step and take-a- breath

  2. Physical Workload and Work Capacity across Occupational Groups.

    Directory of Open Access Journals (Sweden)

    Stefanie Brighenti-Zogg

    Full Text Available This study aimed to determine physical performance criteria of different occupational groups by investigating physical activity and energy expenditure in healthy Swiss employees in real-life workplaces on workdays and non-working days in relation to their aerobic capacity (VO2max. In this cross-sectional study, 337 healthy and full-time employed adults were recruited. Participants were classified (nine categories according to the International Standard Classification of Occupations 1988 and merged into three groups with low-, moderate- and high-intensity occupational activity. Daily steps, energy expenditure, metabolic equivalents and activity at different intensities were measured using the SenseWear Mini armband on seven consecutive days (23 hours/day. VO2max was determined by the 20-meter shuttle run test. Data of 303 subjects were considered for analysis (63% male, mean age: 33 yrs, SD 12, 101 from the low-, 102 from the moderate- and 100 from the high-intensity group. At work, the high-intensity group showed higher energy expenditure, metabolic equivalents, steps and activity at all intensities than the other groups (p<0.001. There were no significant differences in physical activity between the occupational groups on non-working days. VO2max did not differ across groups when stratified for gender. The upper workload limit was 21%, 29% and 44% of VO2max in the low-, moderate- and high-intensity group, respectively. Men had a lower limit than women due to their higher VO2max (26% vs. 37%, when all groups were combined. While this study did confirm that the average workload limit is one third of VO2max, it showed that the average is misrepresenting the actual physical work demands of specific occupational groups, and that it does not account for gender-related differences in relative workload. Therefore, clinical practice needs to consider these differences with regard to a safe return to work, particularly for the high-intensity group.

  3. KINETIC CONSEQUENCES OF CONSTRAINING RUNNING BEHAVIOR

    Directory of Open Access Journals (Sweden)

    John A. Mercer

    2005-06-01

    Full Text Available It is known that impact forces increase with running velocity as well as when stride length increases. Since stride length naturally changes with changes in submaximal running velocity, it was not clear which factor, running velocity or stride length, played a critical role in determining impact characteristics. The aim of the study was to investigate whether or not stride length influences the relationship between running velocity and impact characteristics. Eight volunteers (mass=72.4 ± 8.9 kg; height = 1.7 ± 0.1 m; age = 25 ± 3.4 years completed two running conditions: preferred stride length (PSL and stride length constrained at 2.5 m (SL2.5. During each condition, participants ran at a variety of speeds with the intent that the range of speeds would be similar between conditions. During PSL, participants were given no instructions regarding stride length. During SL2.5, participants were required to strike targets placed on the floor that resulted in a stride length of 2.5 m. Ground reaction forces were recorded (1080 Hz as well as leg and head accelerations (uni-axial accelerometers. Impact force and impact attenuation (calculated as the ratio of head and leg impact accelerations were recorded for each running trial. Scatter plots were generated plotting each parameter against running velocity. Lines of best fit were calculated with the slopes recorded for analysis. The slopes were compared between conditions using paired t-tests. Data from two subjects were dropped from analysis since the velocity ranges were not similar between conditions resulting in the analysis of six subjects. The slope of impact force vs. velocity relationship was different between conditions (PSL: 0.178 ± 0.16 BW/m·s-1; SL2.5: -0.003 ± 0.14 BW/m·s-1; p < 0.05. The slope of the impact attenuation vs. velocity relationship was different between conditions (PSL: 5.12 ± 2.88 %/m·s-1; SL2.5: 1.39 ± 1.51 %/m·s-1; p < 0.05. Stride length was an important factor

  4. Short and long term effects of the Copenhagen school child intervention study (CoSCIS) on cardiovascular risk factors

    DEFF Research Database (Denmark)

    Bugge, Anna; Hermansen, Bianca El-Naaman; Froberg, Karsten

    13.35 yr in 7th grade). BMI, sum of 4 skinfolds (S4SF) and waist to hip ratio (WHR) were measured. PA was measured using CSA accelerometers for four consecutive days. Aerobic fitness (VO2max) was directly measured during a maximal progressive running test on a treadmill. Fasting intravenous blood...

  5. A influência do genótipo da ECA sobre a aptidão cardiovascular de jovens do sexo masculino moderadamente ativos The influence of ACE genotype on cardiovascular fitness of moderately active young men

    Directory of Open Access Journals (Sweden)

    Jeeser Alves Almeida

    2012-04-01

    Full Text Available FUNDAMENTO: O gene da enzima conversora de angiotensina (gene ECA tem sido amplamente estudado em relação a fenótipos de aptidão cardiorrespiratória, contudo a associação do genótipo da ECA com corridas de meia-distância tem sido pouco investigada. OBJETIVO: O presente estudo investigou a possível influência da enzima conversora de angiotensina (ECA (I/D sobre a aptidão cardiovascular e o desempenho em corridas de meia-distância por parte de brasileiros jovens do sexo masculino. A validade da previsão de VO2max em relação ao genótipo da ECA também foi analisada. MÉTODOS: Um grupo homogêneo de homens jovens moderadamente ativos foi avaliado em um teste de corrida (V1600 m; m.min-1 e em um teste adicional em esteira ergométrica para a determinação de VO2max. Posteriormente, o [(0,177*V1600m + 8.101] VO2max real e previsto foi comparado com os genótipos da ECA. RESULTADOS: O VO2max e V1600m registrados para os genótipos DD, ID e II foram 45,6 (1,8; 51,9 (0,8 e 54,4 (1,0 mL.kg-1.min-1 e 211,2 (8,3; 249,1 (4,3 e 258,6 (5,4 m.min-1, respectivamente e foram significativamente mais baixos para os genótipos DD (p BACKGROUND: The angiotensin I-converting enzyme gene (ACE gene has been broadly studied as for cardiorespiratory fitness phenotypes, but the association of the ACE genotype to middle-distance running has been poorly investigated. OBJECTIVE: This study investigated the possible influence of Angiotensin-Converting Enzyme (ACE genotype (I/D on cardiovascular fitness and middle-distance running performance of Brazilian young males. The validity of VO2max to predict the ACE genotype was also analyzed. METHODS: A homogeneous group of moderately active young males were evaluated in a 1,600 m running track test (V1600m; m.min-1 and in an incremental treadmill test for VO2max determination. Subsequently, the actual and the predicted [(0.177*V1600m + 8.101] VO2max were compared to ACE genotypes. RESULTS: The VO2max and V1600m

  6. Determination of Aerobic Performance in Youth Soccer Players: Effect of Direct And Indirect Methods

    Science.gov (United States)

    Higino, Wonder Passoni; Sorroche, Alex de Souza; de Mattos Falqueiro, Pedro Guilherme; Suzuki Lima, Yuri Cristina; Higa, Camila Lie

    2017-01-01

    Abstract This study was conducted to correlate and compare values for variables determined in indirect tests with the values determined directly in youth soccer players. The study subjects were 27 youth soccer players (age 16.77 ± 0.75 years; body mass 63.29 ± 7.37 kg; body height 174.14 ± 8.46 cm) playing in the basic categories of a first division team at the regional level of Brazilian soccer. Each subject was evaluated with the following tests: a) a treadmill test to directly determine values of VO2max and Vamax (Treadmill); b) an indirect Shuttle Run Test (SRT); c) an indirect Carminatti’s test (TCar). VO2max showed significantly different values in the Treadmill and the SRT (59.21 ± 5.88 and 50.67 ± 3.58 ml⋅kg−1⋅min−1, respectively). Similarly, values obtained for VPeak in the treadmill test and for Vamax in TCar were different from values for SRT VPeak (15.01 ± 1.10, 14.92 ± 0.87 and 12.64 ± 0.62 km⋅h−1, respectively). A correlation analysis showed a moderate relationship between values for VPeak TCar and VO2max determined on a treadmill (r = 0.46) and Vamax determined on a treadmill (r = 0.54). The analysis also showed a high correlation between values of VO2max determined on the treadmill and VO2max evaluated in the SRT (r = 0.69), as well as VPeak determined in the SRT and VO2max tested on the treadmill (r = 0.71), as well as between VPeak determined in the SRT and VO2max evaluated on the treadmill (r = 0.77). We concluded that the SRT underestimated values of VO2max and Vamax. Additionally, VPeak TCar showed no difference compared to Vamax, although it did show a low correlation with it. In addition the SRT, even with high correlations, did not seem to be a great predictor of aerobic fitness in youth soccer players. PMID:28469749

  7. Running surface couplings

    OpenAIRE

    1995-01-01

    We discuss the renormalization group improved effective action and running surface couplings in curved spacetime with boundary. Using scalar self-interacting theory as an example, we study the influence of the boundary effects to effective equations of motion in spherical cap and the relevance of surface running couplings to quantum cosmology and symmetry breaking phenomenon. Running surface couplings in the asymptotically free SU(2) gauge theory are found.

  8. Oxygen delivery does not limit peak running speed during incremental downhill running to exhaustion.

    Science.gov (United States)

    Liefeldt, G; Noakes, T D; Dennis, S C

    1992-01-01

    Oxygen consumption (VO2), ventilation (VI), respiratory exchange ratio (R), stride frequency and blood lactate concentrations were measured continuously in nine trained athletes during two continuous incremental treadmill runs to exhaustion on gradients of either 0 degree or -3 degrees. Compared to the run at 0 degree gradient, the athletes reached significantly higher maximal treadmill velocities but significantly lower VO2, VI, R and peak blood lactate concentrations (P less than 0.001) during downhill running. These lower VO2 and blood lactate concentrations at exhaustion indicated that factors other than oxygen delivery limited maximal performance during the downhill run. In contrast, stride frequencies were similar at each treadmill velocity; the higher maximal speed during the downhill run was achieved with a significantly longer stride length (P less than 0.001); maximal stride frequency was the same between tests. Equivalent maximal stride frequencies suggested that factors determining the rate of lower limb stride recovery may have limited maximal running speed during downhill running and, possibly, also during horizontal running.

  9. Concurrent training in elite male runners: the influence of strength versus muscular endurance training on performance outcomes.

    Science.gov (United States)

    Sedano, Silvia; Marín, Pedro J; Cuadrado, Gonzalo; Redondo, Juan C

    2013-09-01

    Much recent attention has been given to the compatibility of combined aerobic and anaerobic training modalities. However, few of these studies have reported data related to well-trained runners, which is a potential limitation. Therefore, because of the limited evidence available for this population, the main aim was to determine which mode of concurrent strength-endurance training might be the most effective at improving running performance in highly trained runners. Eighteen well-trained male runners (age 23.7 ± 1.2 years) with a maximal oxygen consumption (VO2max) more than 65 ml·kg(-1)·min(-1) were randomly assigned into 1 of the 3 groups: Endurance-only Group (n = 6), who continued their usual training, which included general strength training with Thera-band latex-free exercise bands and endurance training; Strength Group (SG; n = 6) who performed combined resistance and plyometric exercises and endurance training; Endurance-SG (ESG; n = 6) who performed endurance-strength training with loads of 40% and endurance training. The study comprised 12 weeks of training in which runners trained 8 times a week (6 endurance and 2 strength sessions) and 5 weeks of detraining. The subjects were tested on 3 different occasions (countermovement jump height, hopping test average height, 1 repetition maximum, running economy (RE), VO2max, maximal heart rate [HRmax], peak velocity (PV), rating of perceived exertion, and 3-km time trial were measured). Findings revealed significant time × group interaction effects for almost all tests (p training for both SG and ESG groups led to improved maximal strength, RE, and PV with no significant effects on the VO2 kinetics pattern. The SG group also seems to show improvements in 3-km time trial tests.

  10. Aerobic fitness and performance in elite female futsal players

    Directory of Open Access Journals (Sweden)

    JC Barbero-Alvarez

    2016-01-01

    Full Text Available Despite its growing popularity, few studies have investigated specific physiological demands for elite female futsal. The aim of this study was to determine aerobic fitness in elite female futsal players using laboratory and field testing. Fourteen female futsal players from the Venezuelan National team (age =21.2±4.0 years; body mass =58.6±5.6 kg; height =161±5.0 cm performed a progressive maximal treadmill test under laboratory conditions. Players also performed a progressive intermittent futsal-specific field test for endurance, the Futsal Intermittent Endurance Test (FIET, until volitional fatigue. Outcome variables were exercise heart rate (HR, VO2, post-exercise blood lactate concentrations ([La]b and running speeds (km • h -2 . During the treadmill test, VO2max, maximal aerobic speed (MAS, HR and peak [La]b were 45.3±5.6 ml • kg-1 • min-1, 12.5±1.77 km • h -2 , 197±8 beats • min-1 and 11.3±1.4 mmol • l-1, respectively. The FIET total distance, peak running velocity, peak HR and [La]b were 1125.0±121.0 m, 15.2±0.5 km • h -2 , 199±8 beats • min-1 and 2.5±2.2 mmol • l-1, respectively. The FIET distance and peak speed were strongly associated (r= 0.85-87, p<0.0001 with VO2max and MAS, respectively. Peak HR and [La]b were not significantly different between tests. Elite female futsal players possess moderate aerobic fitness. Furthermore, the FIET can be considered as a valid field test to determine aerobic fitness in elite level female futsal players.

  11. Aerobic fitness and performance in elite female futsal players

    Science.gov (United States)

    Subiela, JV; Granda-Vera, J; Castagna, C; Gómez, M; Del Coso, J

    2015-01-01

    Despite its growing popularity, few studies have investigated specific physiological demands for elite female futsal. The aim of this study was to determine aerobic fitness in elite female futsal players using laboratory and field testing. Fourteen female futsal players from the Venezuelan National team (age =21.2±4.0 years; body mass =58.6±5.6 kg; height =161±5.0 cm) performed a progressive maximal treadmill test under laboratory conditions. Players also performed a progressive intermittent futsal-specific field test for endurance, the Futsal Intermittent Endurance Test (FIET), until volitional fatigue. Outcome variables were exercise heart rate (HR), VO2, post-exercise blood lactate concentrations ([La]b) and running speeds (km · h-1). During the treadmill test, VO2max, maximal aerobic speed (MAS), HR and peak [La]b were 45.3±5.6 ml · kg-1 · min-1, 12.5±1.77 km · h-1, 197±8 beats · min-1 and 11.3±1.4 mmol · l-1, respectively. The FIET total distance, peak running velocity, peak HR and [La]b were 1125.0±121.0 m, 15.2±0.5 km · h-1, 199±8 beats · min-1 and 12.5±2.2 mmol · l-1, respectively. The FIET distance and peak speed were strongly associated (r= 0.85-87, p < 0.0001) with VO2max and MAS, respectively. Peak HR and [La]b were not significantly different between tests. Elite female futsal players possess moderate aerobic fitness. Furthermore, the FIET can be considered as a valid field test to determine aerobic fitness in elite level female futsal players. PMID:28479664

  12. Evaluation of energy expenditure in forward and backward movements performed by soccer referees

    Directory of Open Access Journals (Sweden)

    M.R. Paes

    2016-01-01

    Full Text Available The aim of this study was to measure the energy expenditure for locomotor activities usually performed by soccer referees during a match (walking, jogging, and running under laboratory conditions, and to compare forward with backward movements. The sample was composed by 10 male soccer referees, age 29±7.8 years, body mass 77.5±6.2 kg, stature 1.78±0.07 m and professional experience of 7.33±4.92 years. Referees were evaluated on two separate occasions. On the first day, maximal oxygen uptake (VO2max was determined by a maximal treadmill test, and on the second day, the oxygen consumption was determined in different speeds of forward and backward movements. The mean VO2max was 41.20±3.60 mL·kg-1·min-1 and the mean heart rate achieved in the last stage of the test was 190.5±7.9 bpm. When results of forward and backward movements were compared at 1.62 m/s (walking speed, we found significant differences in VO2, in metabolic equivalents, and in kcal. However, the same parameters in forward and backward movements at jogging velocities (2.46 m/s were not significantly different, showing that these motor activities have similar intensity. Backward movements at velocities equivalent to walking and jogging are moderate-intensity activities, with energy expenditure less than 9 kcal. Energy expenditure was overestimated by at least 35% when calculated by mathematical equations. In summary, we observed that backward movements are not high-intensity activities as has been commonly reported, and when calculated using equations available in the literature, energy expenditure was overestimated compared to the values obtained by indirect calorimetry.

  13. Biomechanics of sprint running. A review.

    Science.gov (United States)

    Mero, A; Komi, P V; Gregor, R J

    1992-06-01

    Understanding of biomechanical factors in sprint running is useful because of their critical value to performance. Some variables measured in distance running are also important in sprint running. Significant factors include: reaction time, technique, electromyographic (EMG) activity, force production, neural factors and muscle structure. Although various methodologies have been used, results are clear and conclusions can be made. The reaction time of good athletes is short, but it does not correlate with performance levels. Sprint technique has been well analysed during acceleration, constant velocity and deceleration of the velocity curve. At the beginning of the sprint run, it is important to produce great force/power and generate high velocity in the block and acceleration phases. During the constant-speed phase, the events immediately before and during the braking phase are important in increasing explosive force/power and efficiency of movement in the propulsion phase. There are no research results available regarding force production in the sprint-deceleration phase. The EMG activity pattern of the main sprint muscles is described in the literature, but there is a need for research with highly skilled sprinters to better understand the simultaneous operation of many muscles. Skeletal muscle fibre characteristics are related to the selection of talent and the training-induced effects in sprint running. Efficient sprint running requires an optimal combination between the examined biomechanical variables and external factors such as footwear, ground and air resistance. Further research work is needed especially in the area of nervous system, muscles and force and power production during sprint running. Combining these with the measurements of sprinting economy and efficiency more knowledge can be achieved in the near future.

  14. Applying the cost of generating force hypothesis to uphill running

    Directory of Open Access Journals (Sweden)

    Wouter Hoogkamer

    2014-07-01

    Full Text Available Historically, several different approaches have been applied to explain the metabolic cost of uphill human running. Most of these approaches result in unrealistically high values for the efficiency of performing vertical work during running uphill, or are only valid for running up steep inclines. The purpose of this study was to reexamine the metabolic cost of uphill running, based upon our understanding of level running energetics and ground reaction forces during uphill running. In contrast to the vertical efficiency approach, we propose that during incline running at a certain velocity, the forces (and hence metabolic energy required for braking and propelling the body mass parallel to the running surface are less than during level running. Based on this idea, we propose that the metabolic rate during uphill running can be predicted by a model, which posits that (1 the metabolic cost of perpendicular bouncing remains the same as during level running, (2 the metabolic cost of running parallel to the running surface decreases with incline, (3 the delta efficiency of producing mechanical power to lift the COM vertically is constant, independent of incline and running velocity, and (4 the costs of leg and arm swing do not change with incline. To test this approach, we collected ground reaction force (GRF data for eight runners who ran thirty 30-second trials (velocity: 2.0–3.0 m/s; incline: 0–9°. We also measured the metabolic rates of eight different runners for 17, 7-minute trials (velocity: 2.0–3.0 m/s; incline: 0–8°. During uphill running, parallel braking GRF approached zero for the 9° incline trials. Thus, we modeled the metabolic cost of parallel running as exponentially decreasing with incline. With that assumption, best-fit parameters for the metabolic rate data indicate that the efficiency of producing mechanical power to lift the center of mass vertically was independent of incline and running velocity, with a value of ∼29

  15. The Ergogenic Effect of Amphetamine.

    Science.gov (United States)

    Zaretsky, Dmitry V; Brown, Mary Beth; Zaretskaia, Maria V; Durant, Pamela J; Rusyniak, Daniel E

    Amphetamine (Amp) increases exercise duration. It is thought to do so by masking fatigue, but there have been very few studies looking at the effect of amphetamine on VO2MAX and running economy. Furthermore, it is unknown if amphetamine's effect on exercise duration occurs in a warm environment. We conducted separate experiments in male Sprague-Dawley rats testing the effect of amphetamine on maximal oxygen consumption (VO2MAX) (n=12), running economy (n=12), and exercise duration (n=24) in a warm environment. For VO2MAX and running economy, rats were randomized to either amphetamine at 1 mg/kg (Amp-1) or 2 mg/kg (Amp-2). Animals served as their own controls in a crossover design with the administration order counter-balanced. To study the effect of amphetamine on exercise duration, we conducted run-to-exhaustion treadmill testing on rats in a 32°C environment following administration of Amp-1, Amp-2, or Saline. Compared to control, Amp-2 increased VO2MAX (by 861 ± 184 ml/kg/hr, p=0.005) and the time to VO2MAX (by 2.5 ± 0.8 min, p=0.03). Amp-1 had no effect on VO2MAX but increased the time to VO2MAX (by 1.7 ± 0.5 min, p=0.03). Neither dose improved running economy. In the warm, only rats in the Amp-1 group (+9.4 min, p=0.02) had an increased time to exhaustion. Compared to control (41.6 ± 0.3°C), both amphetamine doses had higher temperatures at exhaustion: Amp-1 (42.0 ± 0.2°C) and Amp-2 (42.1 ± 0.2°C). Our results suggest that ergogenic effect of amphetamine occurs by masking fatigue but this effect may be offset in the warm with higher doses.

  16. Overuse injuries in running

    DEFF Research Database (Denmark)

    Larsen, Lars Henrik; Rasmussen, Sten; Jørgensen, Jens Erik

    2016-01-01

    What is an overuse injury in running? This question is a corner stone of clinical documentation and research based evidence.......What is an overuse injury in running? This question is a corner stone of clinical documentation and research based evidence....

  17. Running to Extremes

    Institute of Scientific and Technical Information of China (English)

    PHILIP JONES

    2010-01-01

    @@ For some, simply running 21 km, or a full marathon at 42 kin, isn't enough of an achievement. I mean, you can run a marathon in almost every major city in the world and many of them are centerpiece events watched by a global audience.

  18. Influence of repeated bouts of eccentric exercise on high-intensity aerobic performance.

    Science.gov (United States)

    Higino, Wonder Passoni; Aparecido de Souza, Renato; Cavalcanti, Fabio de Sousa; Cardoso, Anderlei Dos Santos; Vasconcelos, Murilo Victor; Fernandes da Silva, Fabiano; Leme, José Alexandre C A

    2016-08-01

    [Purpose] It is believed that eccentric high-intensity exercise can decrease performance in subsequent exercise. However, with repetition, the deleterious effects can be minimized. Thus, this study evaluated the influence of repeated bouts of eccentric exercise on subsequent high-intensity aerobic performance. [Subjects and Methods] Seven healthy and sedentary male volunteers were recruited. a) Visit 1: determination of maximum oxygen uptake (VO2max) and speed associated with maximum oxygen uptake (vVO2max) in incremental treadmill testing; b) Visit 2: run to exhaustion at vVO2max (Tlim control); c) Visit 3: 10 sets of 10 depth jumps, followed by a run to exhaustion at vVO2max (Tlim 1); d) Visit 4: after 6 weeks without any physical training, the volunteers carried out the same procedures as on the third visit (Tlim 2). Data were analyzed using one-way analysis of variance (ANOVA) with the post-hoc Tukey test. [Results] Significant differences were found between Tlim control and Tlim 1 (283.4 ± 47.7 s vs. 125.2 ± 64.1 s, respectively), these were not different from Tlim 2. [Conclusion] Eccentric exercise showed deleterious effects on subsequent high-intensity aerobic performance. These effects were minimized after the exercise protocol was repeated 6 weeks after the first event.

  19. Running Economy from a Muscle Energetics Perspective

    Directory of Open Access Journals (Sweden)

    Jared R. Fletcher

    2017-06-01

    Full Text Available The economy of running has traditionally been quantified from the mass-specific oxygen uptake; however, because fuel substrate usage varies with exercise intensity, it is more accurate to express running economy in units of metabolic energy. Fundamentally, the understanding of the major factors that influence the energy cost of running (Erun can be obtained with this approach. Erun is determined by the energy needed for skeletal muscle contraction. Here, we approach the study of Erun from that perspective. The amount of energy needed for skeletal muscle contraction is dependent on the force, duration, shortening, shortening velocity, and length of the muscle. These factors therefore dictate the energy cost of running. It is understood that some determinants of the energy cost of running are not trainable: environmental factors, surface characteristics, and certain anthropometric features. Other factors affecting Erun are altered by training: other anthropometric features, muscle and tendon properties, and running mechanics. Here, the key features that dictate the energy cost during distance running are reviewed in the context of skeletal muscle energetics.

  20. Velocity condensation for magnetotactic bacteria

    CERN Document Server

    Rupprecht, Jean-Francois; Bocquet, Lydéric

    2015-01-01

    Magnetotactic swimmers tend to align along magnetic field lines against stochastic reorientations. We show that the swimming strategy, e.g. active Brownian motion versus run-and-tumble dynamics, strongly affects the orientation statistics. The latter can exhibit a velocity condensation whereby the alignment probability density diverges. As a consequence, we find that the swimming strategy affects the nature of the phase transition to collective motion, indicating that L\\'evy run-and-tumble walks can outperform active Brownian processes as strategies to trigger collective behavior.