Pfirrmann, Daniel; Herbst, Mark; Ingelfinger, Patrick; Simon, Perikles; Tug, Suzan
Context: The incidence of injury for elite youth and professional adult soccer players is an important concern, but the risk factors for these groups are different. Objective: To summarize and compare the injury incidences and injury characteristics of male professional adult and elite youth soccer players. Data Sources: We searched MEDLINE and Web of Science using the search terms elite, international, European, soccer, football, injury, injuries, epidemiology, incidence, prevalence, not female, not American football, and not rugby. We also used the search terms professional for studies on professional adult soccer players and high-level, soccer academy, youth, adolescent, and young for studies on elite youth soccer players. Study Selection: Eligible studies were published in English, had a prospective cohort design, and had a minimum study period of 6 months. To ensure that injury data were assessed in relationship to the athlete's individual exposure, we included only studies that reported on injuries and documented exposure volume. Data Extraction: Two independent reviewers applied the selection criteria and assessed the quality of the studies. Data Synthesis: A total of 676 studies were retrieved from the literature search. Eighteen articles met the inclusion criteria: 6 for elite youth and 12 for professional adult soccer players. Conclusions: Injury rates were higher for matches than for training for both youth and adult players. Youth players had a higher incidence of training injuries than professionals. Efforts must be made to reduce the overall injury rate in matches. Therefore, preventive interventions, such as adequately enforcing rules and focusing on fair play, must be analyzed and developed to reduce match-related injury incidences. Reducing training injuries should be a particular focus for youth soccer players. PMID:27244125
Mosler, Andrea B; Crossley, Kay M; Waarsing, Jan H; Jomaah, Nabil; Weir, Adam; Hölmich, Per; Agricola, Rintje
Participation in high-impact athletic activities has recently been associated with a higher prevalence of cam deformity. Bony hip morphology has also emerged as an important factor in the development of hip osteoarthritis. However, it is unknown whether bony morphology differs between ethnicities in athletes participating in high-impact sports. To investigate whether the prevalence of specific bony hip morphological abnormalities differed between professional male soccer players of diverse ethnic backgrounds. Cross-sectional study; Level of evidence, 3. Professional male soccer players from an entire league attending preparticipation screening were invited to participate in this study. Ethnicity was registered, and standardized radiographs of anteroposterior pelvic and Dunn views were obtained. Cam and pincer deformity, and acetabular dysplasia were quantified using the alpha angle, triangular index, and lateral center-edge angle (LCEA). Regression analyses with generalized estimating equations were used to determine prevalence differences in bony hip morphology. A total of 445 male soccer players (890 hips; mean age ± SD, 25 ± 4.9 years) participated in the study, representing the following ethnic groups: Arabic (59%), black (24%), Persian (7%), white (6%), East Asian (2%), and other (2%). The prevalence of cam deformity (alpha angle >60°) ranged from 57.5% to 71.7% across 4 of the groups, but East Asians had a significantly lower prevalence (18.8%; P ≤ .032). A large cam deformity (alpha angle >78°) was more prevalent in white (33.3%) compared with black soccer players (17.8%; P = .041) and was absent in East Asian players. Pincer deformity (LCEA >40°) was uncommon (3%) in all ethnicities. The prevalence of acetabular dysplasia (LCEA <20°) ranged from 8.0% to 16.7%, apart from the white group, in which prevalence was only 1.9% (P = .03). The prevalence of a cam deformity and acetabular dysplasia differed between ethnicities in this cohort of professional
Full Text Available To present time, scientific knowledge about symptoms of common mental disorders and adverse health behaviours among professional soccer players is lacking. Consequently, the aim of the study was to determine the prevalence of symptoms of common mental disorders (distress, anxiety/depression, sleep disturbance and adverse health behaviours (adverse alcohol behaviour, smoking, adverse nutrition behaviour among professional soccer players, and to explore their associations with potential stressors (severe injury, surgery, life events and career dissatisfaction. Cross-sectional analyses were conducted on baseline questionnaires from an ongoing prospective cohort study among male professional players. Using validated questionnaires to assess symptoms of common mental disorders and adverse health behaviours as well as stressors, an electronic questionnaire was set up and distributed by players’ unions in 11 countries from three continents. Prevalence of symptoms of common mental disorders and adverse health behaviours among professional soccer players ranged from 4% for smoking and 9% for adverse alcohol behaviour to 38% for anxiety/depression and 58% for adverse nutrition behaviour. Significant associations were found for a higher number of severe injuries with distress, anxiety/depression, sleeping disturbance and adverse alcohol behaviour, an increased number of life events with distress, sleeping disturbance, adverse alcohol behaviour and smoking, as well as an elevated level of career dissatisfaction with distress, anxiety/depression and adverse nutrition behaviour. Statistically significant correlations (p<0.01 were found for severe injuries and career dissatisfaction with most symptoms of common mental disorders. High prevalence of symptoms of common mental disorders and adverse health behaviours was found among professional players, confirming a previous pilot-study in a similar study population.
aus der Fünten, Karen; Faude, Oliver; Lensch, Jochen; Meyer, Tim
The winter break in the top 2 German professional soccer leagues was shortened from 6.5 to 3.5 weeks in the 2009-2010 season. To investigate whether this change affected injury characteristics by comparing the second half of the 2008-2009 (long winter break) with the equivalent period in the 2009-2010 season (short winter break). Prospective cohort study. German male professional soccer leagues. Seven professional German male soccer teams (184 players in the 2008-2009 season, 188 players in the 2009-2010 season). Injury incidences and injury characteristics (cause of injury, location, severity, type, diagnosis), including their monthly distribution, were recorded. A total of 300 time-loss injuries (2008-2009 n = 151, 2009-2010 n = 149) occurred. The overall injury incidence per 1000 soccer hours was 5.90 (95% confidence interval = 5.03, 6.82) in 2008-2009 and 6.55 (5.58, 7.69) in 2009-2010. Match injuries per 1000 hours were 31.5 (25.0, 38.0) in the first season and 26.5 (20.2, 32.7) in the second season; the corresponding training values were 2.67 (2.08-3.44) and 3.98 (3.19-4.95), respectively. The training injury incidence (incidence rate ratio = 1.49 [95% confidence interval = 1.07, 2.08], P = .02) and the risk of sustaining a knee injury (incidence rate ratio = 1.66 [1.00, 2.76], P = .049) were higher in 2009-2010 after the short winter break; the incidence of moderate and severe injuries (time loss >7 days) trended higher (incidence rate ratio = 1.34 [0.96, 1.86], P = .09). Shortening the winter break from 6.5 to 3.5 weeks did not change the overall injury incidence; however, a higher number of training, knee, and possibly more severe injuries (time loss >7 days) occurred.
Kästner, Andreas; Braun, Markus; Meyer, Tim
We report 2 cases of enormously elevated creatine kinase (CK) activity after training with electromyostimulation (EMS) by 2 young male professional soccer players. In one of them, a single training session with EMS caused exercise-induced rhabdomyolysis with a maximal CK activity of 240 000 U/L. These cases illustrate that unaccustomed EMS exercise may be harmful and can cause rhabdomyolysis even in highly trained athletes and even after 1 single session. Thus, EMS has to be conducted carefully especially by individuals who are known to frequently show notable increases in CK activity even after modest training stimuli. We suggest that EMS should not be applied as sole training stimulus and should not be conducted by strength training beginners. Furthermore, we recommend controlling plasma CK activity and urine color for beginners with EMS when they report strong muscle ache. Athletes with signs of rhabdomyolysis after EMS should be brought to hospital for monitoring of renal function and possible further treatment.
Li, Shaolin; Zhao, Wenji; Hao, Shuai; Hu, Shaoyong; Zhang, Rui; Zhang, Xintao
To analyze the imaging abnormal findings of ankle injuries in professional soccer player of males. The thirty-two professional soccer players in local region soccer club had been selected as research objects from March 2014 to January 2015, and all were men. Average age was 22.03±3.0 years old (19-33 years); the average age was 8.6±2.0 years old that began to engage in professional football training, and average time of engaged in football sports was 13±4 years (7-27 years). X-ray examination was used VM DR (Philips Co.), anteroposterior and lateral position of ankle joints. CT scan was used MSCT of 64 rows detector (Aquilion 64, TOSHIBA Co.). After routine scan, raw data was transmitted to the workstation and then reconstructed to be axial, sagittal, coronal imaging. MR examination was used 1.5 T superconducting equipment system (Achieva Dual, Philips Co.) and with ankle joint special phased array coil. TSE sequence be used to scan routine axial T2-weighted imaging; coronal T1-weighted imaging; coronal PWI; and sagittal T2-weighted imaging with fat suppressed. The sagittal PWI scan was used with Isotropic with fat suppressed FFE sequence. The X-ray examination was finished for 28 person and 51 ankle joints. 26 person and 52 ankle joints were completed CT scan and reconstructed imaging for all joints. MR examination was finished in 30 person and 51 ankle joints. On X-ray and CT display that the abnormal changes of the talus is most commonly found that the incidence of "dolphin mouth" like protrusion at posterior edge was 35 ankles (rate of occurrence was 68.6%), the triangle prominence at out edge was 45 ankles (rate of occurrence was 88.2%). It also was found that 8 lateral malleolus have osteophytes, 5 ankles have medial malleolus osteophytes and 12 ankles have loose bodies at posterior ankle. MRI showed that 30 ankles were the anterior talofibular ligaments injury and incidence was 58.82%, 26 ankles were posterior talofibular ligaments injury (incidence was
Stubbe, Janine H.; van Beijsterveldt, Anne-Marie M. C.; van der Knaap, Sissi; Stege, Jasper; Verhagen, Evert A.; van Mechelen, Willem; Backx, Frank J. G.
Context: Injuries are a major adverse event in a soccer player's career. Reducing injury incidence requires a thorough knowledge of the epidemiology of soccer injuries. Objective: To investigate the incidence and characteristics of injuries in the Dutch premier soccer league. Design: Cohort study. Setting: The Dutch premier soccer league. Patients or Other Participants: During the 2009–2010 soccer season, a total of 217 professional soccer players from 8 teams were prospectively followed. Main Outcome Measure(s): The medical staff recorded time-loss injuries, including information on injuries (ie, type, body part, duration) and exposure data for training sessions and matches. Results: A total of 286 injuries were recorded, affecting 62.7% of the players. The overall injury incidence was 6.2 injuries per 1000 player-hours, 2.8 in training sessions and 32.8 in matches. Most of the recorded injuries were acute (68.5%). Eight percent of the injuries were classified as recurrent. Injuries were most likely to be located in the lower extremities (82.9%). Injury time loss ranged from 1 to 752 days, with a median of 8 days. Knee injuries had the greatest consequences in terms of days of absence from soccer play (on average, 45 days). The most common diagnosis was muscle/tendon injury of the lower extremities (32.9%). Conclusions: Injury risk in the Dutch premier soccer league is high, especially during matches. Preventive measures should focus on the most common diagnoses, namely, muscle/tendon injuries of the lower extremities. PMID:25531144
Gouttebarge, Vincent; Aoki, Haruhito; Kerkhoffs, Gino
To present time, scientific knowledge about symptoms of common mental disorders and adverse health behaviours among professional soccer players is lacking. Consequently, the aim of the study was to determine the prevalence of symptoms of common mental disorders (distress, anxiety/depression, sleep
Niall A. Clark
Full Text Available The purpose of this study was to examine season-to-season variations in physiological fitness parameters among a 1st team squad of professional adult male soccer players for the confirmatory purposes of identifying normative responses (immediately prior to pre-season training (PPS, mid-season (MID, and end-of-season (EOS. Test-retest data were collected from a student population on the primary dependent variables of anaerobic threshold (AT and maximal aerobic power (VO2 max to define meaningful measurement change in excess of test-retest technical error between test-to-test performances. Participants from a pool of 42 professional soccer players were tested over a set sequence of tests during the 3-year period: 1 basic anthropometry, 2 countermovement jump (CMJ tests 3 a combined AT and VO2 max test. Over the 3-year period there were no test-to-test changes in mean VO2 max performance exceeding pre-defined limits of test agreement (mean of eight measures: 61.6 ± 0.6 ml·kg-1·min-1. In contrast, VO2 at AT was significantly higher at the MID test occasion in seasons 2 (+4.8%; p = 0.04, p < 0.05 and 3 (+6.8%; p = 0.03, p < 0.05. The CMJ tests showed a test-to-test improvement of 6.3% (best of 3 jumps (p = 0.03, p < 0.05 and 10.3% (20-s sustained jumping test (p = 0.007, p < 0.01 between PPS2 and MID2 and thereafter remained stable. Anthropometrics were unaffected. In summary, despite some personnel changes in the elite cohort between test-to-test occasions, VO2 max values did not vary significantly over the study which supports previous short-term observations suggesting a general 'elite' threshold of 60 ml·kg-1 min. Interestingly, AT significantly varied where VO2 max was stable and these variations also coincided with on- and off-seasons suggesting that AT is a better indication of acute training state than VO2 max.
Grassi, Alberto; Smiley, Stephen Paul; Roberti di Sarsina, Tommaso; Signorelli, Cecilia; Marcheggiani Muccioli, Giulio Maria; Bondi, Alice; Romagnoli, Matteo; Agostini, Alessandra; Zaffagnini, Stefano
Soccer is considered the most popular sport in the world concerning both audience and athlete participation, and the incidence of ACL injury in this sport is high. The understanding of injury situations and mechanisms could be useful as substratum for preventive actions. To conduct a video analysis evaluating the situations and mechanisms of ACL injury in a homogeneous population of professional male soccer players, through a search entirely performed on the YouTube.com Web site focusing on the most recent years. A video analysis was conducted obtaining videos of ACL injury in professional male soccer players from the Web site YouTube. Details regarding injured players, events and situations were obtained. The mechanism of injury was defined on the basis of the action, duel type, contact or non-contact injury, and on the hip, knee and foot position. Thirty-four videos were analyzed, mostly from the 2014-2015 season. Injuries occurred mostly in the first 9 min of the match (26%), in the penalty area (32%) or near the side-lines (44%), and in non-rainy conditions (97%). Non-contact injuries occurred in 44% of cases, while indirect injuries occurred in 65%, mostly during pressing, dribbling or tackling. The most recurrent mechanism was with an abducted and flexed hip, with knee at first degrees of flexion and under valgus stress. Through a YouTube-based video analysis, it was possible to delineate recurrent temporal, spatial and mechanical characteristics of ACL injury in male professional soccer players. Level IV, case series.
Yamaner, Faruk; Gumusdag, Hayrettin; Kartal, Alparslan; Gumus, M.; Gullu, A.; Imamoglu, O.
Study aim: To assess the prevalence and anatomical sites of injuries in professional soccer players in one game season. Material and methods: A cohort of 510 professional male soccer players consisting of 48 goalkeepers, 194 defence players, 189 mid-field players and 79 forward players of the 1st and 2nd Turkish Professional Soccer Leagues in…
Milanese, Chiara; Cavedon, Valentina; Corradini, Giuliano; De Vita, Francesco; Zancanaro, Carlo
This work investigated changes in body composition of professional soccer players attending an Italian Serie A club across the competitive season; it is original insofar as body composition was assessed at multiple time points across the season using the accurate three-compartment model provided by Dual-Energy X-Ray Absorptiometry (DXA). Thirty-one players (4 goalkeepers, 13 defenders, 8 midfielders, 6 forwards) underwent DXA and anthropometry at pre-, mid- and end-season. One operator measured whole body and regional body composition (fat mass, FM; fat-free soft tissue mass, FFSTM; mineral mass). Two players were excluded from analysis due to serious injury. Data were analysed with repeated measures ANOVA; factors were season time point and playing position. Results showed that whole-body FM and %FM significantly (P professional soccer players undergo changes in their FM, FFSTM, and mineral mass across the season with some regional variations, irrespective of the playing position. Changes are mostly positive at mid-season, possibly due to difference in training between the first and second phase of the season.
Roescher, C. R.; Elferink-Gemser, M. T.; Huijgen, B. C. H.; Visscher, C.
The development of intermittent endurance capacity, its underlying mechanisms and role in reaching professional level in soccer was investigated. The sample included 130 talented youth soccer players aged 14-18, who became professional (n = 53) or non-professional (n = 77) players in adulthood. In
Stubbe, J.H.; Beijsterveldt, A.M. van; Knaap, S. van der; Stege, J.; Verhagen, E.; Mechelen, W. van; Backx, F.J.G.
Context : Injuries are a major adverse event in a soccer player's career. Reducing injury incidence requires a thorough knowledge of the epidemiology of soccer injuries. Objective : To investigate the incidence and characteristics of injuries in the Dutch premier soccer league. Design : Cohort
Full Text Available PURPOSE: We aimed to investigate the effect of FIFA 11+ (11+ and HarmoKnee injury preventive warm-up programs on conventional strength ratio (CSR, dynamic control ratio (DCR and fast/slow speed ratio (FSR in young male professional soccer players. These ratios are related to the risk of injury to the knee in soccer players. METHODS: Thirty-six players were divided into 3 groups; FIFA 11+, HarmoKnee and control (n = 12 per group. These exercises were performed 3 times per week for 2 months (24 sessions. The CSR, DCR and FSR were measured before and after the intervention. RESULTS: After training, the CSR and DCR of knee muscles in both groups were found to be lower than the published normal values (0.61, 0.72, and 0.78 during 60°.s(-1, 180°.s(-1 and 300°.s(-1, respectively. The CSR (60°.s(-1 increased by 8% and FSR in the quadriceps of the non-dominant leg by 8% in the 11+. Meanwhile, the DCR in the dominant and non-dominant legs were reduced by 40% and 30% respectively in the 11+. The CSR (60°.s(-1 in the non-dominant leg showed significant differences between the 11+, HarmoKnee and control groups (p = 0.02. As for the DCR analysis between groups, there were significant differences in the non-dominant leg between both programs with the control group (p = 0.04. For FSR no significant changes were found between groups. CONCLUSIONS: It can be concluded that the 11+ improved CSR and FSR, but the HarmoKnee program did not demonstrate improvement. We suggest adding more training elements to the HarmoKnee program that aimed to enhance hamstring strength (CSR, DCR and FSR. Professional soccer players have higher predisposition of getting knee injuries because hamstring to quadriceps ratio were found to be lower than the average values. It seems that the 11+ have potentials to improve CSR and FSR as well as prevent knee injuries in soccer players.
Schiffner, Erik; Latz, David; Grassmann, Jan P; Schek, Alberto; Scholz, Armin; Windolf, Joachim; Jungbluth, Pascal; Schneppendahl, Johannes
Aim of this retrospective cohort study was to identify fracture epidemiology and off times after different types of fractures in German male elite soccer players from the first division Bundesliga based on information from the public media. Exposure and fracture data over 7.5 consecutive seasons (2009/10 -1.Half 2016/17) were collected from two media based register (transfermarkt.de® and kicker.de®). 357 fractures from 290 different players were recorded with an incidences of 0.19/1000 h of exposure (95% 0.14 - 0.24). Most fractures in German elite soccer players involved the lower extremities (35.3%), the head/face (30.3%) and the upper extremities (24.9%). The median off time after a fracture in German elite male professional soccer in 7.5 Season was 51.1 days (range 0-144). The number of fractures per 100 players per season decreased between 2009 and 2016. There was no significant difference in overall fracture incidence when comparing players at different position (p=0.11). Goalkeepers have a significantly (pelite soccer. The incidence of fractures in elite German soccer players decreased between 2009 and 2016. The most fractures occur in the lower extremities and there is no difference in overall fracture risk for players at different playing positions. The information from our study might be of a great importance to medical practitioners, soccer coaches and soccer manager.
Van Yperen, Nico W.
This prospective study was designed to identify psychological factors that predict career success in professional adult soccer. Post hoc, two groups were distinguished: (1) Male soccer players who Successfully progressed into professional adult soccer (n = 18) and (2) Male soccer players who did not
Lanzetti, R M; Ciompi, A; Lupariello, D; Guzzini, M; De Carli, A; Ferretti, A
Our hypothesis is that there are no difference in the injury incidence on artificial turf and natural grass. During the 2011/2012 season, we recorded injuries which occurred to two Italian stadiums equipped with third-generation artificial turf during 36 games (391 players). Data were compared with the injuries which occurred in the same season in two stadiums equipped with natural grass (372 players). We recorded 43 injuries during the playing time (16.7 per 1000 h). About 23 (18.1 per 1000 h) injuries occurred on artificial turf, while 20 (15.2 per 1000 h) on the natural grass with no statistical differences P > 0.05. We recorded 10 (7.87 per 1000 h) contact and 13 (10.23 per 1000 h) non-contact injuries on artificial turf, while 5 (3.8 per 1000 h) contact and 15 (11.4 per 1000 h) non-contact injuries on natural grass P > 0.05. The overall relative risk was 1.15; 95% CI: 0.64-2.07). Our study demonstrates a substantial equivalence in injury risk on natural grass and artificial turf in elite professional soccer athletes during official matches. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Anne-Marie van Beijsterveldt, A. M C; Stubbe, J. H.; Schmikli, S. L.; Van De Port, I. G L; Backx, F. J G|info:eu-repo/dai/nl/069615039
Objectives To compare the incidence and characteristics of injuries between Dutch amateur and professional male soccer players during one entire competition season. Design A prospective two-cohort design. Methods During the 2009–2010 season, 456 Dutch male amateur soccer players and 217 professional
Proietti, Riccardo; di Fronso, Selenia; Pereira, Lucas A; Bortoli, Laura; Robazza, Claudio; Nakamura, Fabio Y; Bertollo, Maurizio
Heart rate variability (HRV) has been increasingly used to monitor team sports athletes. Besides the traditional time domain indices (i.e., the SD of successive RR intervals [SDNN] and the root mean square difference of successive normal RR intervals [RMSSD]), recently the use of the stress score (SS), which is an inverse function of the SD2 index derived from the Poincaré plot, and the sympathetic/parasympathetic ratio (S/PS) to monitor soccer players has been proposed. However, the reliability of these new indices and the ability of HRV to differentiate between soccer competitive levels are unknown. The aim of this study was to analyze the reliability of the different HRV-derived indices in professional soccer players during the competitive period and to compare HRV of professional soccer players from 3 teams of distinct competitive levels (i.e., Italian Second Division [2D], European League [EL], and Champions League [CL]). Fifty-four male professional soccer players from 3 different teams of 2 European countries (Italy and Germany) participated in the study. The intraclass correlation coefficient values of the HRV indices varied from 0.78 (very large) to 0.90 (near perfect). The coefficient of variation (CV) values for RMSSD and SDNN were all soccer players and is able to differentiate between international- and national-level players.
Owoeye, Oluwatoyosi Babatunde Alex; Aiyegbusi, Ayoola Ibifubara; Fapojuwo, Oluwaseun Akinleye; Badru, Oluwaseun Abdulganiyu; Babalola, Anike Rasheedat
Research on the epidemiology of football injuries in Africa is very sparse despite its importance for injury prevention planning in a continent with limited sports medicine resources. The vast majority of studies available in literature were conducted in Europe and only a very few studies have prospectively reported the pattern of football injury in Africa. The purpose of this study was to evaluate the incidence and pattern of injuries in a cohort of male and female semi-professional football players in Nigeria. A prospective cohort design was conducted, in which a total of 756 players with an age range of 18-32 years (356 males and 300 females) from 22 different teams (12 male and 10 female teams), were prospectively followed in a National Football Tournament. Physiotherapists recorded team exposure and injuries. Injuries were documented using the consensus protocol for data collection in studies relating to football injury surveillance. An overall incidence of 113.4 injuries/1000 h (95% CI 93.7-136.0) equivalent to 3.7 injuries/match and time-loss incidence of 15.6 injuries/1000 h were recorded for male players and 65.9 injuries/1000 h (95% CI 48.9-86.8) equivalent to 2.2 injuries/match and time-loss incidence of 7.9 injuries/1000 h were recorded for female players. Male players had a significantly higher risk of injuries [IRR = 1.72 (95% CI 1.23-2.45)]. Injuries mostly affected the lower extremity for both genders (n = 81, 70% and n = 31, 62% for males and females respectively). Lower leg contusion (n = 22, 19%) and knee sprain (n = 9, 18%) were the most common specific injury types for male and female players respectively. Most of the injuries were as a result of contact with another player (n = 102, 88%-males; n = 48, 96%-females). Time-loss injuries were mostly estimated as minimal (n = 11, 69%) for male players and severe (n = 4, 66%) for female players. The overall incidence of injuries among Nigerian semi-professional football
Beijsterveldt, A.M.C. van; Stubbe, J.H.; Schmikli, S.L.; Port, I.G.L. van de; Backx, F.J.G.
Objectives: To compare the incidence and characteristics of injuries between Dutch amateur and professional male soccer players during one entire competition season. Design: A prospective two-cohort design. Methods: During the 2009-2010 season, 456 Dutch male amateur soccer players and 217
Beijsterveldt, A.M. van; Steffen, K.; Stubbe, J.H.; Frederiks, J.E.; Port, I.G.L. van de; Backx, F.J.G.
OBJECTIVE:: To describe characteristics of outdoor soccer injury and recovery among Dutch soccer players. DESIGN:: Prospective cohort study. SETTING:: The 2009-2010 competitive season (33 weeks). PARTICIPANTS:: Four hundred fifty-six Dutch male soccer players of 23 amateur teams. MAIN OUTCOME
Thorborg, Kristian; Branci, Sonia; Stensbirk, Frederik
BACKGROUND/AIM: Reference values are needed in order to interpret the Copenhagen Hip and Groin Outcome Score (HAGOS) in male soccer players with hip and groin pain. The aim of this study was to establish reference values for HAGOS in hip and groin injury-free male soccer players. METHODS: We...
Ehrmann, Fabian E; Duncan, Craig S; Sindhusake, Doungkamol; Franzsen, William N; Greene, David A
This study investigated the relationship between GPS variables measured in training and gameplay and injury occurrences in professional soccer. Nineteen professional soccer players competing in the Australian Hyundai A-League were monitored for 1 entire season using 5 Hz Global Positioning System (GPS) units (SPI-Pro GPSports) in training sessions and preseason games. The measurements obtained were total distance, high-intensity running distance, very-high-intensity running distance, new body load, and meters per minute. Noncontact soft tissue injuries were documented throughout the season. Players' seasons were averaged over 1- and 4-week blocks according to when injuries occurred. These blocks were compared with each other and with players' seasonal averages. Players performed significantly higher meters per minute in the weeks preceding an injury compared with their seasonal averages (+9.6 and +7.4% for 1- and 4-week blocks, respectively) (p Football Association regulations, the results of this study isolated 2 variables predicting soft tissue injuries for coaches and sports scientists to consider when planning and monitoring training.
Raizel, Raquel; Godois, Allan da Mata; Coqueiro, Audrey Yule; Voltarelli, Fabrício Azevedo; Fett, Carlos Alexandre; Tirapegui, Julio; Ravagnani, Fabricio Cesar de Paula; Coelho-Ravagnani, Christianne de Faria
Despite the well-documented importance of nutrition in optimizing performance and health, the dietary intake of soccer players has attracted little attention. We aimed to assess the pre-season dietary intake of professional soccer players and its adequacy in macro and micronutrients. The pre-season dietary intake of 19 male athletes was assessed using a semi-structured 3-day food record. To determine dietary adequacy and excess, energy and macronutrient intake were compared with the Brazilian dietary reference values for athletes, and micronutrients were compared with the Estimated Average Requirement - EAR (minimum recommendation) and Tolerable Upper Intake Level - UL (maximum recommendation). Mean daily energy intake (40.74±12.81 kcal/kg) was adequate. However, there was a low carbohydrate intake (5.44±1.86 g/kg/day) and a high amount of protein and fat (1.91±0.75 and 1.27±0.50 g/kg/day, respectively). Sodium intake (3141.77±939.76 mg/day) was higher than UL (2300 mg/day), while the majority of players showed daily intake of vitamin A (74%), vitamin D (100%), folate (58%), calcium and magnesium (68%) below the EAR (625, 10 and 320 µg/day, 800 and 330 mg/day, respectively). The dietary intake of professional soccer players was adequate in energy, but inadequate in macro and micronutrients, which suggests the need to improve nutritional practices to sustain the physical demands of soccer during pre-season.
Nikolaos E Koundourakis
Full Text Available The current study had two aims. The primary purpose was to examine the association between serum vitamin D levels and the ergometric evaluation of muscle strength, aerobic capacity, and speed in professional soccer players. The secondary aim was to evaluate the effects of the soccer off-season period on serum vitamin D levels.Sixty-seven Caucasian male soccer players (age 25.6 ± 6.2 and height 1.81 ± 0.08 m, members of two Greek Superleague Soccer teams and one Football-league championship team participated in this study. Exercise performance testing for the determination of squat jump (SJ, countermovement jump (CMJ, 10 (10 m and 20 meters (20 m sprint performance, maximal oxygen consumption (VO2max, anthropometry, and blood sampling were performed before (pre and after (post the six-week off-season period.Analysis of our results showed the following: (a a significant correlations between serum vitamin D levels and performance parameters in both pre (SJ; P < 0.001, CMJ; P < 0.001, VO2max; P < 0.001, 10 m; P < 0.001, and 20 m; P < 0.001 and post (SJ; P < 0.001, CMJ; P<0.001, VO2max; P = 0.006, 10 m; P < 0.001, and 20 m; P < 0.001 experimental sessions. (b Vitamin D concentration increased significantly (P < 0.001 following the six-week off-season period compared to baseline, while at the same time all measured performance parameters decreased (SJ; P < 0.001, CMJ; P < 0.001, 10 m; P < 0.001, 20 m; P < 0.001, VO2max; P<0.001.Our findings suggest that vitamin D levels are associated with the ergometric evaluation of muscle strength, as expressed by SJ and CMJ, sprinting capacity, and VO2max in professional soccer players, irrespective the levels of performance. Furthermore, our data reaffirm the importance of UVB on serum vitamin D levels. Moreover, reductions in exercise training stress may also have beneficial effects on vitamin D levels, suggesting a possible association of its levels and the training-induced stress. Our results indicate a
While retirement traditionally occurs for most non-athletes after a long working career that allows them to plan and anticipate the likely demands and ... It is therefore important for soccer clubs and agents to assist professional soccer players in career counselling to be both mentally and financially prepared for retirement.
Paulus, Jan; Tong, Jie; Hornegger, Joachim; Schmidt, Michael; Eskofier, Björn; Michelson, Georg
Stereopsis is one of several visual depth cues. It has been evaluated for athletes of different types of sports in the past. However, most studies do not cover the full range of stereopsis performance. Therefore, we propose computer-supported stereopsis tests that provide an extended assessment and analysis of stereopsis performance including stereo acuity and response times. By providing stationary and moving stimuli they cover static and dynamic stereopsis, respectively. The proposed stereopsis tests were used to compare professional and amateur soccer players with subjects without soccer background. The soccer players could not perform significantly (p ≤ 0.05) superior than the subjects without soccer background. However, the soccer players showed significantly (p ≤ 0.01) superior choice reaction times for monocular stimuli. The results are in congruence with previous findings in literature. PMID:25368596
Full Text Available Stereopsis is one of several visual depth cues. It has been evaluated for athletes of different types of sports in the past. However, most studies do not cover the full range of stereopsis performance. Therefore, we propose computer-supported stereopsis tests that provide an extended assessment and analysis of stereopsis performance including stereo acuity and response times. By providing stationary and moving stimuli they cover static and dynamic stereopsis. The proposed stereopsis tests were used to compare professional and amateur soccer players with subjects without soccer background. The soccer players could not perform significantly (p <= 0.05 superior than the subjects without soccer background. However, the soccer players showed significantly (p <= 0.01 superior choice reaction times for monocular stimuli. The results are in congruence with previous findings in literature.
O'Brien, James; Finch, Caroline F
Background There are well-known challenges to implementing injury prevention strategies in amateur soccer, but information from other soccer settings is scarce. This cross-sectional survey analysed the injury prevention perceptions of soccer coaches, fitness coaches and physiotherapists from 4 male teams in a professional youth soccer academy. Methods The respondents (n=18) completed a web-based survey relating to lower limb (LL) soccer injuries, the value and practicality of injury prevention exercise programmes (IPEPs) in general and, more specifically, the IPEP endorsed by FIFA, the FIFA 11+. Results There were very high levels of agreement regarding players’ susceptibility to LL injury and the seriousness of these injuries. Respondents agreed unanimously that players should perform evidence-based injury prevention exercises. Despite 61% of respondents having previously heard of the FIFA 11+, just 6% reported current use of the full programme, with a further 22% reporting modified use. 22% believed the FIFA 11+ contained adequate variation and progression for their team and 78% felt it needed improvement. Respondents identified multiple barriers and facilitators to maintaining IPEPs, relating either to the programme content (eg, exercise variation), or the delivery and support of the programme (eg, coach acceptance). Conclusions The coaches, fitness coaches and physiotherapists of professional youth teams support the use of IPEPs, but enhancing their impact requires tailoring of programme content, along with adequate delivery and support at multiple levels. The findings suggest that the FIFA 11+ needs modification for use in professional youth soccer teams. PMID:27900158
Owen, Adam L.; Dunlop, Gordon; Rouissi, Mehdi; Haddad, Monoem; Mendes, Bruno; Chamar, Karim
The primary aim of the study was to perform a comparative analysis of the positional training loads during various game formats among European professional soccer players. Twenty-two male professional soccer players participated in the investigation and were divided into their tactical positional roles for analysis. Ratings of perceived exertion were collected daily and corresponded to specific formatted game types (small-sided games; large-sided games; large-sided games within a ...
O'Brien, James; Young, Warren; Finch, Caroline F
Injury prevention exercise programmes for amateur soccer have gained considerable attention, but little is known about their relevance and adaptability to professional soccer settings. The first aim of this study was to evaluate the delivery and content of injury prevention exercise programmes used by professional youth soccer teams, compared to the industry standard injury prevention exercise programme for soccer, the Fédération Internationale de Football Association's FIFA 11+. The second aim was to document specific challenges to implementing injury prevention exercise programmes in this context. Prospective observational study. The participants were soccer coaches, fitness coaches and physiotherapists (n=18) from four teams in a professional youth soccer academy. Each team's chosen injury prevention exercise programmes were observed weekly across an entire soccer season (160 sessions). The delivery and content of the programmes were documented on a standardised worksheet and compared to the FIFA 11+. Specific implementation challenges were recorded. Fitness coaches were the primary deliverers of injury prevention exercise programmes, with support from physiotherapists. Multiple delivery formats and locations were employed, along with the extensive use of equipment. Across all injury prevention exercise programme sessions, a median of one FIFA 11+ exercise was performed in its original form and a further four in a modified form. Implementation challenges included poor staff communication, competing training priorities and heavy game schedules. Although the basic components of the FIFA 11+ hold relevance for professional youth male teams, the delivery and content of injury prevention exercise programmes require considerable tailoring for this context. Recognising this will inform the development of improved, context-specific injury prevention exercise programmes, along with corresponding strategies to enhance their implementation. Copyright © 2016 Sports
Full Text Available The purpose of this study was to analyse the leadership power perception of amateur and professional soccer coaches according to their marital status. Data were collected from 165 male soccer coaches (n=71 technical director-manager and A license, n=46 B license, n=48 amateur license. An adapted Turkish version of Power in Soccer Questionnaire-Self (PSQ-S for coaches and an information form were used for the data collection . Cronbach reliability alphas of PSQ-S range between 0.65 and 0.84. Coaches’ data were analysed by Kruskal-Wallis and Mann-Whitney tests. Kruskal-Wallis analysis of PSQ-S revealed significant differences between leadership power perception of amateur and professional soccer coaches according to their marital status related to Referent Power (RP [χ[sup]2[/sup] (3 = 9.61, p0.05. The results indicated that married coaches have higher perception of RP than single coaches, irrespective of being an amateur or a professional. Comparison of professional and amateur coaches suggests that while single professional coaches have higher perception of EP than married professional coaches, the results are the reverse for amateur coaches; in other words, amateur married coaches have higher perception of EP than amateur single coaches. There is a lack of research to draw more certain conclusions. Future researchers should also take into consideration personality, psychological skills, sport experience, age, taking responsibility, attributions, expectations, emotions, perception of achievement, etc.
Lahner, Matthias; Walter, Philipp Alexander; von Schulze Pellengahr, Christoph; Hagen, Marco; von Engelhardt, Lars Victor; Lukas, Carsten
Femoroacetabular impingement (FAI) represents a novel approach to the mechanical etiology of hip osteoarthritis. The cam-type femoroacetabular impingement deformity occurs frequently in young male athletes. The aim of our study was to evaluate the prevalence of FAI in male semiprofessional soccer players using clinical examination and magnetic resonance imaging (MRI), compared to amateur soccer players. In MRI, the α angle of Nötzli is determined for quantifying FAI. According to power analysis, a total of 22 asymptomatic semiprofessional soccer players with a median of 23.3 years of age (range 18-30 years) and 22 male amateur soccer players with a median of 22.5 years of age (control group, range 18-29 years) underwent an MRI to measure the hip α angle of Nötzli. The α angle of the kicking legs of the semiprofessional group and the amateur group were analyzed. The study group was moreover evaluated by the Hip Outcome Score (HOS) and a clinical hip examination including range of motion (ROM) and impingement tests. In the semiprofessional group, 19 soccer players had a right kicking leg and 1 soccer player had a left kicking leg. 2 soccer players kicked with two feet. In the semi-professional group, the mean value of the α angle of the kicking leg (57.3 ± 8.2°) was significantly higher than in the amateur group (51.7 ± 4.8°, P = 0.008). In the semi-professional group, 15 (62.5 %) of 24 kicking legs had an increased α angle >55°, while 5 (27.3 %) kicking legs of the amateur group had an α angle >55°. Five semi professional soccer players had findings in clinical examination, whereof 4 had an increased α angle >55°. No participant of the amateur group showed pathological results in the clinical examination (P = 0.0484). Overall, semiprofessional soccer players had a higher proportion of an increased α angle than the amateur group. Semiprofessional players have a higher prevalence of an increased α angle in the kicking leg than the amateur group at
Full Text Available Strength imbalances between the hamstrings and quadriceps are an essential predictor for hamstring strain in soccer. The study aimed to investigate and compare the muscle strength imbalances of professional soccer players of different performance levels. One hundred and fifty nine senior male professional soccer players from first (n = 75 and second league (n = 84 Portuguese clubs participated in this study. Muscle strength was evaluated with a REV9000 isokinetic dynamometer. Maximal peak torque data were used to calculate quadriceps and hamstrings strength during concentric and eccentric actions, bilateral asymmetry, conventional strength ratios and dynamic control ratios. Second league athletes produced slightly lower conventional strength ratios in the right and left legs (ES = 0.22, p = 0.17 and ES = 0.36, p = 0.023, respectively compared to the first league athletes. No significant differences were found in dynamic control ratios or in bilateral asymmetry among first and second league athletes. These findings do not show a clear link between the competitive level and injury risk in soccer players. However, some of the differences found, particularly in conventional strength ratios, highlight the importance of performing off-season and pre-season strength assessments to prescribe and adjust individual strength training programs among professional soccer players.
Baumgart, C; Hoppe, M W; Freiwald, J
The aims of the present study were to assess gender differences regarding lactate threshold and intermittent shuttle run performance in female and male soccer players as well as to investigate the relationships between both endurance characteristics in both genders. Fourteen female (1(st) division) and thirteen male (4(th) division) soccer players completed an incremental test (IT) to determine running velocities at 2 and 4 mmol · l(-1) blood lactate (v2 and v4) and maximum velocity (vmax) as well as an interval shuttle run test (ISRT) to determine running distance. Based on v2 and v4 and their percentages in relation to vmax, three intensity zones were calculated: a low lactate zone (v4). Female soccer players have a lower v4 (8.2%), vmax (11.3%) and ISRT distance (31.6%). No gender difference was found in v2. In contrast to males, ISRT distance correlates with vmax as well as with v2 and v4 in female soccer players. The intensity zones v4 differ between genders. The present study revealed that gender differences increase when the running performance is intermittent including change of directions. In both genders, different relationships between lactate threshold and intermittent shuttle run performance exist. During incremental testing, the running performances of female and male players reflect different distributions of aerobic and anaerobic metabolic pathways. The revealed gender differences should be considered for soccer endurance training.
Full Text Available The aims of the present study were to assess gender differences regarding lactate threshold and intermittent shuttle run performance in female and male soccer players as well as to investigate the relationships between both endurance characteristics in both genders. Fourteen female (1st division and thirteen male (4th division soccer players completed an incremental test (IT to determine running velocities at 2 and 4 mmol · l-1 blood lactate (v2 and v4 and maximum velocity (vmax as well as an interval shuttle run test (ISRT to determine running distance. Based on v2 and v4 and their percentages in relation to vmax, three intensity zones were calculated: a low lactate zone (v4. Female soccer players have a lower v4 (8.2%, vmax (11.3% and ISRT distance (31.6%. No gender difference was found in v2. In contrast to males, ISRT distance correlates with vmax as well as with v2 and v4 in female soccer players. The intensity zones v4 differ between genders. The present study revealed that gender differences increase when the running performance is intermittent including change of directions. In both genders, different relationships between lactate threshold and intermittent shuttle run performance exist. During incremental testing, the running performances of female and male players reflect different distributions of aerobic and anaerobic metabolic pathways. The revealed gender differences should be considered for soccer endurance training.
van Beijsterveldt, A M C Anne-Marie; Stubbe, J H; Schmikli, S L; van de Port, I G L; Backx, F J G
To compare the incidence and characteristics of injuries between Dutch amateur and professional male soccer players during one entire competition season. A prospective two-cohort design. During the 2009-2010 season, 456 Dutch male amateur soccer players and 217 professional players were prospectively followed. Information on injuries and individual exposure to all soccer activities were recorded in both cohorts. Injuries were recorded using the time-loss definition. In total, 424 injuries were recorded among 274 of the amateur players (60.1% injured players) and 286 injuries were sustained by 136 (62.7% injured players) of the professional players (p=0.52). Compared to the professionals, the injury incidence during training sessions was higher among amateurs (p=0.01), but the injury incidence among professionals was higher during matches (pamateurs (all pamateurs reported more recurrent injuries (pamateur and professional players in the Netherlands might be explained by the difference in the level at which they play, since factors like the availability of medical support and/or the team size may influence the injury risk and characteristics. Copyright © 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.
Koning, Ruud H.; Amelink, Remko
Professional athletes such as soccer players are expected to be in better health than the average member of their age cohort, if only because of the very demands imposed on them by their profession. Moreover, during their active career, their health is monitored on a regular basis. However, whenever
Sanchis-Gomar, Fabian; Alis, Rafael; Rampinini, Ermanno; Bosio, Andrea; Romagnoli, Marco; Lombardi, Giovanni; Lippi, Giuseppe
Recent evidence has showed that serum or salivary values of α-amylase predict endurance running performance. In this study we investigate whether serum α-amylase concentration may be associated with training status during a competitive season and after a detraining period in professional soccer players. The study population consisted in 15 male professional soccer players from an Italian major league team (age [mean±SD] 27±5 years, weight 76.9±4.1 kg, height 1.82±0.05 m). Serum α-amylase levels were measured 3 times during the last part of a competitive season (January, March and May) and just before preseason training (July). Metabolic and cardiovascular fitness of soccer players was improved during the last part of the season. The levels of α-amylase did not change significantly throughout the study period (χ2=7.331, P=0.062), nor they were found to be associated with variation of physical fitness and training status. The α-amylase fluctuations throughout a competitive season and after vacation time were meaningless in professional soccer players. No significant associations with physical fitness variations could be observed. These results suggest that α-amylase concentration may be a useful parameter for identifying individual inclination to endurance exercise, but not for predicting actual training status.
Perciavalle, Valentina; Di Corrado, Donatella; Petralia, Maria Cristina; Gurrisi, Lino; Massimino, Simona; Coco, Marinella
The aim of this study was to test the hypothesis that high levels of testosterone during prenatal life, testified by a low second-to-fourth digit ratio (2D:4D), as well as in adulthood affect the aggressive behavior of professional soccer players. Using 18 male professional players from a first level Italian Soccer Team we calculated: i) the 2D:4D ratio of the right hand, ii) the number of yellow and red cards per game, iii) the mean salivary testosterone concentration (Sal/T) and iv) the handling of aggressive impulses as assessed by the Picture Frustration test (PFT). Soccer players with a lower 2D:4D ratio had a higher number of fouls per game. A significant negative correlation was observed between Sal/T and 2D:4D ratio, as well as between 2D:4D ratio and the aggressiveness of players. By contrast, a significant positive correlation of Sal/T and fouls/game score and PFT was detected. No significant correlation was detected between 2D:4D or Sal/T and the playing position of players. Results of this study revealed that in professional soccer players, aggressive behavior, with the consequent increased risk of fouls during the game, is more likely to occur in individuals with high testosterone levels, not only in adulthood, but also during their intrauterine life.
Wong-On, Manuel; Turmo-Garuz, Antonio; Arriaza, Rafael; Gonzalez de Suso, Jose Manuel; Til-Perez, Luis; Yanguas-Leite, Xavier; Diaz-Cueli, David; Gasol-Santa, Xavier
Obturator externus and internus muscular tears are uncommon injuries. Only a few case reports exist, mainly in high-level athletes. Our aim is to describe a series of obturator externus and internus muscular tears in professional soccer players. Injury data from four teams from the First Division of the Spanish Soccer League were collected over a total of four seasons. Any soccer player who sustained an injury to either the obturator externus or internus identified on magnetic resonance (MRI) was included. All injured players were treated non-operatively with a goal of returning to play as fast as possible. Sixteen players sustained injuries to the obturator externus and internus during matches or training sessions. The main complaint was anterior hip pain with a physical examination showing pain during internal rotation or external rotation of the flexed hip. The MRI documented 12 muscular tears of the obturator externus, and 4 muscular tears of the obturator internus. All injuries were treated conservatively based on physical therapy, analgesic medications, and underwent a symptoms-based rehabilitation protocol. Mean return to play was 11.5 ± 8.8 days. Although uncommon, tears of the obturator externus and internus occur in professional soccer players. The MRI scan was essential to the location, classification, and evaluation of the injury size. The clinical relevance of our investigation is based on the relatively benign prognosis of these injuries. IV.
Read, Paul J; Oliver, Jon L; de Ste Croix, Mark B A; Myer, Gregory D; Lloyd, Rhodri S
Read, PJ, Oliver, JL, de Ste Croix, MBA, Myer, GD, and Lloyd, RS. Reliability of the tuck jump injury risk screening assessment in elite male youth soccer players. J Strength Cond Res 30(6): 1510-1516, 2016-Altered neuromuscular control has been suggested as a mechanism for injury in soccer players. Ligamentous injuries most often occur during dynamic movements, such as decelerations from jump-landing maneuvers where high-risk movement patterns are present. The assessment of kinematic variables during jump-landing tasks as part of a preparticipation screen is useful in the identification of injury risk. An example of a field-based screening tool is the repeated tuck jump assessment. The purpose of this study was to analyze the within-subject variation of the tuck jump screening assessment in elite male youth soccer players. Twenty-five pre-peak height velocity (PHV) and 25 post-PHV elite male youth soccer players from the academy of a professional English soccer club completed the assessment. A test-retest design was used to explore the within-subject intersession reliability. Technique was graded retrospectively against the 10-point criteria set out in the screening protocol using two-dimensional video cameras. The typical error range reported for tuck jump total score (0.90-1.01 in pre-PHV and post-PHV players respectively) was considered acceptable. When each criteria was analyzed individually, kappa coefficient determined that knee valgus was the only criterion to reach substantial agreement across the two test sessions for both groups. The results of this study suggest that although tuck jump total score may be reliably assessed in elite male youth soccer players, caution should be applied in solely interpreting the composite score due to the high within-subject variation in a number of the individual criteria. Knee valgus may be reliably used to screen elite youth male soccer players for this plyometric technique error and for test-retest comparison.
Heisterberg, Mette F; Fahrenkrug, Jan; Krustrup, Peter
ABSTRACT: The aim of this study was to make a comprehensive gathering of consecutive detailed blood samples from professional soccer players, and to analyze different blood parameters in relation to seasonal changes in training and match exposure.Blood samples were collected five times during a six...... months period and analyzed for 37 variables in 27 professional soccer players from the best Danish league. Additionally, players were tested for body composition, VO2max and physical performance by the Yo-Yo intermittent endurance sub-max test (IE2).Multiple variations in blood parameters occurred during...... the observation period, including a decrease in hemoglobin and an increase in hematocrit as the competitive season progressed. Iron and transferrin was stabile, whereas ferritin showed a decrease at the end of the season. IgA and IgM increased in the period with basal physical training and at the end...
Gustavo Gonçalves Arliani
Full Text Available OBJECTIVES: This study aims to compare the prevalence of osteoarthritis in two groups: one comprising former professional soccer players and the other comprising non-professional-athlete participants. METHODS: Twenty-seven male former professional soccer players and 30 male volunteers from different non-sports professional areas participated in the study. All participants underwent bilateral knee radiography and magnetic resonance imaging. In addition, the quality of life, knee pain and joint function were evaluated and compared using questionnaires given to all participants in both groups. Specific knee evaluations, with regard to osteoarthritis and quality of life, were performed in both groups using the Knee Injury and Osteoarthritis Outcome Score subjective questionnaires and the Short-form 36. The chi-squared test, Fisher's exact test, the Mann-Whitney U test and Student's t-test were used for group comparisons. RESULTS: The between-groups comparison revealed significant differences in the following: pain, symptoms and quality of life related to the knee in the Knee Injury and Osteoarthritis Outcome Score subscales; the physical aspects subscale of the SF-36; total whole-organ magnetic resonance imaging scores with regard to the dominant and non-dominant knees. Former soccer players had worse scores than the controls in all comparisons. CONCLUSIONS: Both the clinical and magnetic resonance evaluations and the group comparisons performed in this study revealed that former soccer players have a worse quality of life than that of a control group with regard to physical aspects related to the knee; these aspects include greater pain, increased symptoms and substantial changes in radiographic and magnetic resonance images of the knee.
Background Femoroacetabular impingement (FAI) is predominant in young male athletes, but not much is known about gait differences in cases of increased hip alpha angles. In our study, the hip alpha angle of Nötzli of soccer players was quantified on the basis of magnetic resonance imaging (MRI) with axial oblique sequences. The aim of the current study was to compare the rearfoot motion and plantar pressure in male semiprofessional soccer players with increased alpha angles to age-matched ama...
Esteve, Ernest; Rathleff, Michael Skovdal; Vicens-Bordas, Jordi
squeeze strength in relation to past-season groin pain and duration were influenced by current groin pain and age. Study Design: Cross-sectional study; Level of evidence, 3. Methods: In total, 303 male soccer athletes (mean age, 23 ± 4 years; mean weight, 74.0 ± 7.9 kg; mean height, 178.1 ± 6.3 cm) were....... Purpose: To investigate whether soccer athletes with past-season groin pain and with different durations of past-season groin pain had lower preseason hip adductor squeeze strength compared with those without past-season groin pain. We also investigated whether differences in preseason hip adductor...... included in this study. Self-reported data regarding current groin pain, past-season groin pain, and duration were collected. Hip adductor squeeze strength was obtained using 2 different reliable testing procedures: (1) the short-lever (resistance placed between the knees, feet at the examination bed...
Mascarin, Naryana C.; Vargas, Valentine Z.; Vancini, Rodrigo L.; Andrade, Marília S.
Background Anterior cruciate ligament injury is higher in soccer athletes as compared to athletes of other sports. Risk factors for anterior cruciate ligament injury include low knee hamstring/quadriceps strength ratio and bilateral strength deficits. Purpose To investigate isokinetic thigh muscles strength, hamstring/quadriceps strength ratio, and bilateral strength comparisons in athletes who participate in professional soccer, futsal, and beach soccer. Study Design Cross-sectional study. Methods Brazilian professional soccer (n=70), futsal (n=30), and beach soccer (n=12) players were isokinetically assessed to examine strength of knee extensors and flexors at 60 degrees/second in concentric mode, to measure peak torque of dominant and non-dominant limbs. Results In the dominant limb, for extensors muscles, futsal players presented significantly lower peak torque values (223.9 ± 33.4 Nm) than soccer (250.9 ± 43.0 Nm; p=0.02) and beach soccer players (253.1 ± 32.4 Nm; p=0.03). Peak torque for extensor muscles in the non-dominant limb was significantly lower in futsal (224.0 ± 35.8 Nm) than in beach soccer players (256.8 ± 39.8 Nm; p=0.03). Hamstring/quadriceps strength ratio for dominant limbs for futsal (57.6 ± 10.1%), soccer (53.5 ± 8.8%), and beach soccer (56.3 ± 8.4%) players presented no significant differences between groups; however, the mean values were lower than recommended values found in the literature. There were no strength deficits for any of the evaluated groups when compared bilaterally. Conclusions Futsal athletes presented lower values for quadriceps strength than soccer and beach soccer athletes. Futsal, soccer, and beach soccer players presented no strength asymmetries, but they presented with strength imbalance in hamstring/quadriceps strength ratio. Level of Evidence 3 PMID:29234562
Edholm, P; Krustrup, P; Randers, M B
This study investigated the acute effects of a half-time re-warm up on performance and movement patterns in soccer match play. Using a crossover design, 22 professional male players performed traditional passive rest (CON) or a low-intensity re-warm up (RW) during the half-time period of two soccer matches. Before and after the first half and before the second half, maximal sprint and jump performance were evaluated. Time-motion analysis of the first 15 min of each half was conducted. Sprint and jump performance were reduced (P re-warm up effectively attenuates such deteriorations. Less defensive high-intensity running and more ball possession were observed after RW, indicating a game advantage at the onset of the second half. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Edholm, P; Krustrup, Peter; Randers, Morten Bredsgaard
This study investigated the acute effects of a half-time re-warm up on performance and movement patterns in soccer match play. Using a crossover design, 22 professional male players performed traditional passive rest (CON) or a low-intensity re-warm up (RW) during the half-time period of two soccer...... matches. Before and after the first half and before the second half, maximal sprint and jump performance were evaluated. Time–motion analysis of the first 15 min of each half was conducted. Sprint and jump performance were reduced (P ... in CON, whereas sprint performance was maintained and the decrement in jump performance (3.1%; P
de Queiroz, Roberto Dantas; de Carvalho, Rogério Teixeira; de Queiroz Szeles, Paulo Roberto; Janovsky, César; Cohen, Moisés
to evaluate the return to sport after surgical treatment for pubalgia among 30 professional soccer players and describe the surgical technique used. this case series was evaluated by means of a questionnaire and physical examination on 30 male professional soccer players of mean age 24.4 years (range: 18-30). The mean duration of the symptoms was 18.6 months (range: 13-28). The diagnosis was made through clinical investigation, special maneuvers and complementary examinations, by the same examiner. All the patients underwent surgical treatment after conservative treatment failed; all procedures were performed by the same surgeon using the same technique. Nonparametric comparisons were made to investigate the time taken to recover after the surgery, for the patients to return to their sport. five patients evolved with hematoma, with the need to remove the stitches three weeks after the operation because of a small dehiscence at the site of the operative wound. The wound healed completely in all these cases by five weeks after the surgery. Four patients presented dysuria in the first week, but improved in the second postoperative week. The mean time taken to return to training was around eight weeks (range: seven-nine). All the players returned to competitive soccer practice within 16 weeks. When asked about their degree of satisfaction after the operation (satisfied or dissatisfied), taking into consideration their return to the sport, there was 100% satisfaction, and they returned to professional practice at the same competitive level as before the injury. This degree of satisfaction continued to the last assessment, which was made after 36 months of postoperative follow-up. the surgical technique presented in this case series, with trapezoidal resection of the pubic symphysis in association with bilateral partial tenotomy of the long adductor, was a fast and effective procedure with a low rate of postoperative complications. It was shown to be an excellent
Cloak, Ross; Lane, Andrew; Wyon, Matthew
Acute whole body vibration (WBV) is an increasingly popular training technique amongst athletes immediately prior to performance and during scheduled breaks in play. Despite its growing popularity, evidence to demonstrate its effectiveness on acute neuromuscular responses is unclear, and suggestions that athlete ability impacts effectiveness warrant further investigation. The purpose of this study was to compare the neuromuscular effects of acute WBV and perceptions of whether WBV is an effective intervention between amateur and professional soccer players. Participants were 44 male soccer players (22 professional and 22 amateur; age: 23.1 ± 3.7 years, body mass: 75.6 ± 8.8 kg and height: 1.77 ± 0.05 m). Participants in each group were randomly assigned to either an intervention of 3 x 60 s of WBV at 40 Hz (8mm peak-to-peak displacement) or control group. Peak knee isometric force, muscle activation and post activation potentiation (PAP) of the knee extensors along with self-report questionnaire of the perceived benefits of using the intervention were collected. A three-way ANOVA with repeated measures revealed professional players demonstrated a significant 10.6% increase (p amateur players. A significant difference (p amateur players were reported across measurements. Results also indicated professional players reported significantly stronger positive beliefs in the effectiveness of the WBV intervention (p amateur players. Acute WBV elicited a positive neuromuscular response amongst professional players identified by PAP and improvements in knee isometric peak force as well as perceived benefits of the intervention, benefits not found among amateur players. Key pointsAcute WBV improves knee extensor peak isometric force output and PAP amongst professional and not amateur soccer playersProfessional players perceived acute WBV as more beneficial to performance than amateur playersIsometric strength,vibration intensity and duration appear to influence results
Arcos, Asier Los; Martínez-Santos, Raul; Yanci, Javier; Mendiguchia, Jurdan; Méndez-Villanueva, Alberto
The purpose of this study was to examine the usefulness of the rating of perceived exertion training load for monitoring changes in several aerobic fitness and neuromuscular performance variables during 9 weeks of soccer training in young professional players. Nineteen male soccer players (20.2 ± 1.9 years) belonging to the same reserve team of a Spanish La Liga Club participated in this study. Countermovement jump (CMJ), CMJ arm swing, single leg CMJ, a sprint running test (i.e., 5 m and 15 m times) and an aerobic fitness running test were performed at the start of the pre-season (Test 1) and 9 weeks later (Test 2). During 9 weeks, after each training session and match, players reported their rating of perceived exertion (RPE) separately for respiratory (RPEres) and leg musculature (RPEmus) effort. The training load (TL) was calculated by multiplying the RPE value by the duration in minutes of each training session or match. Accumulated RPEmus, and associated TL, as well as accumulated training volume were negatively correlated with the changes in most physical fitness attributes after 9 weeks of training (r = -0.51 to -0.64). Present results suggest that a high perception of leg muscular effort associated with training sessions and matches, as well as an excessive accumulation of training volume (time), can impair the improvement in several physical fitness variables believed to be relevant for on-field soccer performance. Therefore, the independent assessment of leg muscular effort to quantify TL can be an interesting additional monitoring measure in soccer training. Key pointsThe purpose of this study was to examine the usefulness of the perceived exertion-derived TL for monitoring changes in several aerobic fitness and neuromuscular parameters during 9 weeks of soccer training in young professional players.A high perception of leg muscular effort associated with training and matches, as well as an excessive accumulation of training volume (time), can impair
Fábio Augusto Sfoggia Verardi
Full Text Available Abstract: This qualitative study, of descriptive and exploratory manner, aims to determine the formation of youth soccer association structure in the professional soccer clubs in the Rio Pardo and Taquari valleys, in order to modernize the sport nowadays. The subjects of this study are five male administrators of different soccer clubs. The results show that in four of these clubs, the work with youth soccer association is recent, covering only the categories for children, junior and youth with various forms of admissions; but all coaches believe in the commitment of such work. It is observed that its main objective is to train athletes in this association to supply the professional team, without, however, a usual line of tactical system to be observed at different levels. The sponsorship is the main income source for the maintenance of these activities, not being exploited for the dissemination and marketing initiatives. All clubs have trained athletes from the youth soccer association playing in their professional teams, but only one club indicated some indices of those players who were sold or borrowed to other clubs. Thus, it shows that the youth soccer association has received some attention from the sports administrators, but there is still the lack of a better professional management on it, developing its various aspects. So, it could provide more satisfactory results, as a profitable alternative to prepare players for professional teams. Keywords: soccer; structure; clubs, training of athletes.
The purpose of this study was to analyze the leadership power perception of amateur and professional soccer coaches and players according to their belief in good luck or not. Data collected from 165 male soccer coaches and 870 male soccer players including professionals and amateurs. The coaches had a mean age of 40.24 years (SD = 8.40) and had been coaching for an average of 8.56 years (SD = 6.75). The players had a mean age of 18.40 years (SD = 4.00) and had been playing soccer for an average of 6.00 years (SD = 4.15) with license. Adapted Turkish version of Power in Soccer Questionnaire-Other (PSQ-O for soccer players), Power in Soccer Questionnaire-Self (PSQ-S for coaches) and an information form were used for the data collection. Cronbach Reliability Alphas of PSQ-O and PSQ-S range between 0.60 and 0.84. Players' and coaches' data were analyzed by Kruskal-Wallis and Mann Whitney Tests. Analysis of PSQ-O revealed significant differences related to Coersive Power-CP [chi2 (3) = 8.46, p 0.05). Results of PSQ-O and PSQ-S indicated complex relationships related to belief in good luck or not. Overall, there are differences between coaches' and players'perception of CP, LP and EP related to belief in good luck or not. The only similarity appears to be in perception of RP. However, there is lack of research to make more certain conclusions. Future researchers should also take into consideration gender, sport experience, age, taking responsibility, self-confidence, attributions, expectations, superstitions, emotions, perception of achievement etc.
Ruas, Cassio V; Minozzo, Felipe; Pinto, Matheus D; Brown, Lee E; Pinto, Ronei S
Previous investigators have proposed that knee strength, hamstrings to quadriceps, and side-to-side asymmetries may vary according to soccer field positions. However, different results have been found in these variables, and a generalization of this topic could lead to data misinterpretation by coaches and soccer clubs. Thus, the aim of this study was to measure knee strength and asymmetry in soccer players across different field positions. One hundred and two male professional soccer players performed maximal concentric and eccentric isokinetic knee actions on the preferred and nonpreferred legs at a velocity of 60° · s. Players were divided into their field positions for analysis: goalkeepers, side backs, central backs, central defender midfielders, central attacking midfielders, and forwards. Results demonstrated that only goalkeepers (GK) differed from most other field positions on players' characteristics, and concentric peak torque across muscles. Although all players presented functional ratios of the preferred (0.79 ± 0.14) and nonpreferred (0.75 ± 0.13) legs below accepted normative values, there were no differences between positions for conventional or functional strength ratios or side-to-side asymmetry. The same comparisons were made only between field players, without inclusion of the GK, and no differences were found between positions. Therefore, the hamstrings to quadriceps and side-to-side asymmetries found here may reflect knee strength functional balance required for soccer skills performance and game demands across field positions. These results also suggest that isokinetic strength profiles should be considered differently in GK compared with other field positions due to their specific physiological and training characteristics.
Heisterberg, Mette F; Fahrenkrug, Jan; Krustrup, Peter; Storskov, Anders; Kjær, Michael; Andersen, Jesper L
The aim of this study was to make a comprehensive gathering of consecutive detailed blood samples from professional soccer players and to analyze different blood parameters in relation to seasonal changes in training and match exposure. Blood samples were collected 5 times during a 6-month period and analyzed for 37 variables in 27 professional soccer players from the best Danish league. Additionally, the players were tested for body composition, V[Combining Dot Above]O2max and physical performance by the Yo-Yo intermittent endurance submax test (IE2). Multiple variations in blood parameters occurred during the observation period, including a decrease in hemoglobin and an increase in hematocrit as the competitive season progressed. Iron and transferrin were stable, whereas ferritin showed a decrease at the end of the season. The immunoglobulin A (IgA) and IgM increased in the period with basal physical training and at the end of the season. Leucocytes decreased with increased physical training. Lymphocytes decreased at the end of the season. The V[Combining Dot Above]O2max decreased toward the end of the season, whereas no significant changes were observed in the IE2 test. The regular blood samples from elite soccer players reveal significant changes that may be related to changes in training pattern, match exposure, or length of the match season. Especially the end of the preparation season and at the end of the competitive season seem to be time points were the blood-derived values indicate that the players are under excessive physical strain and might be more subjected to a possible overreaching-overtraining conditions. We suggest that regular analyses of blood samples could be an important initiative to optimize training adaptation, training load, and game participation, but sampling has to be regular, and a database has to be built for each individual player.
Maughan, R J
OBJECTIVE: To examine the dietary habits of professional soccer players at two Scottish Premier League clubs during the competitive season. METHODS: A study of the dietary intake of 51 professional soccer players with two different clubs was carried out by the seven day weighed intake method. RESULTS: Physical characteristics of the two groups of players were similar, with only small differences in age and body mass but no difference in height and body fat. Mean (SD) daily energy intake for club A was 11.0 (2.6) MJ, and for club B 12.8 (2.2) MJ. The higher energy intake at club B was largely accounted for by a higher (P carbohydrate, or alcohol consumed. When expressed as a fraction of total energy intake, mean protein intake was higher (P players was not high compared with athletes in endurance sports. Fractional contribution of the macronutrients to total energy intake was broadly similar to that of the general population. PMID:9132211
Malina, Robert M; Figueiredo, António J; Coelho-E-Silva, Manuel J
Studies of the body size and proportions of athletes have a long history. Comparisons of athletes within specific sports across time, though not extensive, indicate both positive and negative trends. To evaluate secular variation in heights and weights of male youth soccer players reported in studies between 1978 and 2015. Reported mean ages, heights, and weights of male soccer players 9-18 years of age were extracted from the literature and grouped into two intervals: 1978-99 and 2000-15. A third-order polynomial was fitted to the mean heights and weights across the age range for each interval, while the Preece-Baines model 1 was fitted to the grand means of mean heights and mean weights within each chronological year to estimate ages at peak height velocity and peak weight velocity for each time interval. Third-order polynomials applied to all data points and estimates based on the Preece-Baines model applied to grand means for each age group provided similar fits. Both indicated secular changes in body size between the two intervals. Secular increases in height and weight between 1978-99 and 2000-15 were especially apparent between 13 and 16 years of age, but estimated ages at peak height velocity (13.01 and 12.91 years) and peak weight velocity (13.86 and 13.77 years) did not differ between the time intervals. Although the body size of youth soccer players increased between 1978-99 and 2000-15, estimated ages at peak height velocity and peak weight velocity did not change. The increase in height and weight likely reflected improved health and nutritional conditions, in addition to the selectivity of soccer reflected in systematic selection and retention of players advanced in maturity status, and exclusion of late maturing players beginning at about 12-13 years of age. Enhanced training programs aimed at the development of strength and power are probably an additional factor contributing to secular increases in body weight.
Russell, Mark; Pennock, Anthony
Limited data exist concerning the dietary practices of young professional soccer players that compete within the United Kingdom. Therefore, the purpose of this study was to investigate the nutritional and activity habits of professional male soccer players (n = 10; age: 17 ± 1 years, height: 1.72 ± 0.01 m, mass: 67.5 ± 1.8 kg, estimated maximal aerobic capacity: 57.8 ± 0.9 ml·kg·min) who played for the youth team of a UK-based Championship club. All players recorded their 7-day dietary intake and activity habits during a competitive week that included a match day, 4- training days, and 2 rest days in the first half of the 2009/2010 playing season. The intake of carbohydrates (5.9 ± 0.4 g·kg·d), proteins (1.7 ± 0.1 g·kg·d), and fats (1.5 ± 0.1 g·kg·d) represented 56 ± 1, 16 ± 1, and 31 ± 1% of the mean daily energy intake respectively. The intake of fiber was found to be significantly lower than Recommended Nutrient Intake (RNI) values (67% of RNI, p soccer players were inadequate to sustain optimized performance throughout training and match play. Youth soccer players should therefore seek to ensure that their diets contain adequate energy through increased total caloric intake, while also optimizing the proportion of energy derived from carbohydrates and ensuring that enough fiber-rich foods are consumed.
Full Text Available Nikolaos E Androulakis,1 Nikolaos E Koundourakis,2 Eleni Nioti,1 Paraskevi Spatharaki,1 Despina Hatzisymeon,1 Ioannis Miminas,1 Michael G Alexandrakis1,3 1Hematology Laboratory, Iraklion University Hospital, Iraklion, Greece; 2Department of Clinical Chemistry-Biochemistry, 3Department of Hematology, School of Medicine, University of Crete, Iraklion, Greece Aim: To examine whether a high volume of soccer-specific training can lead to endothelial activation and/or dysfunction in professional soccer players due to exercise-induced oxidative stress. Methods: Twenty-three (15 nonsmokers and eight smokers healthy, elite male professional soccer players (mean age: 25.2±4.3 years, BMI: 23.1±1.3 kg/m2, fat: 7.8%±2.6% were selected for this study. All participants had a full clinical and laboratory evaluation. von Willebrand factor antigen (vWf Ag plasma levels were measured on two different occasions: 1 day before the beginning of the preseason preparation period and after 7 weeks of strenuous exercise. Results: Mean vWf Ag plasma levels were significantly decreased from 95.1%±26% to 88.3%±27.2% at the end of the experimental period (P=0.018, suggesting a potential beneficial effect on the endothelium of these athletes. Further analysis showed that age greater than 29 years with an age range from 29 to 34 years can not impair this effect (P>0.05. Conclusion: Strenuous exercise did not lead to endothelium activation or dysfunction in well-trained elite soccer players. On the contrary, it seemed to produce a beneficial effect on the endothelium of these players. Keywords: endothelium, strenuous exercise, smoking
Soccer is the most popular sport in the world. Due to i ts global acclaim, a lot of scient ific studies have been undertaken on different aspects of the sport, particularly in Europe. Few studies have investigated patterns of body fat distribution in African soccer players, in general and patterns of fat distribution of soccer players ...
Lahner, Matthias; von Schulze Pellengahr, Christoph; Walter, Philipp Alexander; Lukas, Carsten; Falarzik, Andreas; Daniilidis, Kiriakos; von Engelhardt, Lars Victor; Abraham, Christoph; Hennig, Ewald M; Hagen, Marco
Femoroacetabular impingement (FAI) is predominant in young male athletes, but not much is known about gait differences in cases of increased hip alpha angles. In our study, the hip alpha angle of Nötzli of soccer players was quantified on the basis of magnetic resonance imaging (MRI) with axial oblique sequences. The aim of the current study was to compare the rearfoot motion and plantar pressure in male semiprofessional soccer players with increased alpha angles to age-matched amateur soccer players. In a prospective analysis, male semiprofessional and amateur soccer players had an MRI of the right hip to measure the alpha angle of Nötzli. In a biomechanical laboratory setting, 14 of these participants in each group ran in two shoe conditions. Simultaneously in-shoe pressure distribution, tibial acceleration, and rearfoot motion measurements of the right foot were performed. In the semiprofessional soccer group, the mean value of the alpha angle of group was 55.1 ± 6.58° (range 43.2-76.6°) and 51.6 ± 4.43° (range 41.9-58.8°) in the amateur group. In both shoe conditions, we found a significant difference between the two groups concerning the ground reaction forces, tibial acceleration, rearfoot motion and plantar pressure parameters (P amateur group in both shoe conditions. This study confirmed that semiprofessional soccer players with increased alpha angles showed differences in gait kinematics compared to the amateur group. These findings support the need for a screening program for competitive soccer players. In cases of a conspicuous gait analysis and symptomatic hip pain, FAI must be ruled out by further diagnostic tests.
Daneshjoo, Abdolhamid; Mokhtar, Abdul Halim; Rahnama, Nader; Yusof, Ashril
Purpose The study investigated the effects of FIFA 11+ and HarmoKnee, both being popular warm-up programs, on proprioception, and on the static and dynamic balance of professional male soccer players. Methods Under 21 year-old soccer players (n = 36) were divided randomly into 11+, HarmoKnee and control groups. The programs were performed for 2 months (24 sessions). Proprioception was measured bilaterally at 30°, 45° and 60° knee flexion using the Biodex Isokinetic Dynamometer. Static and dynamic balances were evaluated using the stork stand test and Star Excursion Balance Test (SEBT), respectively. Results The proprioception error of dominant leg significantly decreased from pre- to post-test by 2.8% and 1.7% in the 11+ group at 45° and 60° knee flexion, compared to 3% and 2.1% in the HarmoKnee group. The largest joint positioning error was in the non-dominant leg at 30° knee flexion (mean error value = 5.047), (pproprioception at 45° and 60° knee flexion as well as static and dynamic balance in professional male soccer players. Data from this research may be helpful in encouraging coaches or trainers to implement the two warm-up programs in their soccer teams. PMID:23251579
Full Text Available At the last World Conference on Sport and Physical Therapy celebrated in Bern (Switzerland, 2015, it was confirmed that the functional skills of an athlete are a very important variable to be considered in the recovery of an injury. On the other hand, its use as a predictive risk tool still lacks solid evidence. The purpose of this study was to determine whether a battery of functional tests (FPT could be used as a preliminary measure for the season in order to identify the injury risk in a professional soccer team in the Spanish Second Division B League. Fifty-two soccer players (ages of 25.3 ± 4.6 years, 10.33% ± 0.9% fat were functionally assessed during two seasons (2012–2013 and 2013–2014 and analyzed from an injury perspective. A total of 125 injuries were recorded. The sample was grouped based on the number of injuries and the required absence days. Except for the bipodal vertical jump (CMJ, none of the functional tests revealed differences among the groups. The correlation study between the functional condition and the suffered injuries did not show any significant results.
Beijsterveldt, A.M.C. van
Soccer causes the largest number of injuries each year (18% of all sports injuries) in the Netherlands. The aim of this dissertation is to contribute to the body of evidence on injury prevention for adult male soccer players. Chapter 1 is a general introduction and presents the “sequence of
Beijsterveldt, A.M.C. van; Port, I.G.L. van de; Krist, M.R.; Schmikli, S.L.; Stubbe, J.H.; Frederiks, J.E.; Backx, F.J.G.
The incidence rate of soccer injuries is among the highest in sports, particularly for adult male soccer players. Purpose To investigate the effect of the 'The11' injury prevention programme on injury incidence and injury severity in adult male amateur soccer players. Study design Cluster-randomised
Beijsterveldt, A.M.C. van; Port, I.G.L. van de; Krist, M.R.; Schmikli, S.L.; Stubbe, J.H.; Frederiks, J.E.; Backx, F.J.G.
Background The incidence rate of soccer injuries is among the highest in sports, particularly for adult male soccer players. Purpose To investigate the effect of the 'The11' injury prevention programme on injury incidence and injury severity in adult male amateur soccer players. Study design
Asier Los Arcos, Raul Martínez-Santos, Javier Yanci, Jurdan Mendiguchia, Alberto Méndez-Villanueva
Full Text Available The purpose of this study was to examine the usefulness of the rating of perceived exertion training load for monitoring changes in several aerobic fitness and neuromuscular performance variables during 9 weeks of soccer training in young professional players. Nineteen male soccer players (20.2 ± 1.9 years belonging to the same reserve team of a Spanish La Liga Club participated in this study. Countermovement jump (CMJ, CMJ arm swing, single leg CMJ, a sprint running test (i.e., 5 m and 15 m times and an aerobic fitness running test were performed at the start of the pre-season (Test 1 and 9 weeks later (Test 2. During 9 weeks, after each training session and match, players reported their rating of perceived exertion (RPE separately for respiratory (RPEres and leg musculature (RPEmus effort. The training load (TL was calculated by multiplying the RPE value by the duration in minutes of each training session or match. Accumulated RPEmus, and associated TL, as well as accumulated training volume were negatively correlated with the changes in most physical fitness attributes after 9 weeks of training (r = -0.51 to -0.64. Present results suggest that a high perception of leg muscular effort associated with training sessions and matches, as well as an excessive accumulation of training volume (time, can impair the improvement in several physical fitness variables believed to be relevant for on-field soccer performance. Therefore, the independent assessment of leg muscular effort to quantify TL can be an interesting additional monitoring measure in soccer training.
Jaspers, Arne; Kuyvenhoven, Jurian P; Staes, Filip; Frencken, Wouter G P; Helsen, Werner F; Brink, Michel S
Research in professional soccer focusing on the relevance of external and internal load indicators for injury prevention is scarce. This study examined the relationship between load indicators and overuse injuries. Prospective cohort study. Data were collected from 35 professional male soccer players over two seasons. Following load indicators were examined: total distance covered (TD), distance covered at high speed (THSR; >20kmh -1 ), number of accelerations (ACC eff ; >1ms -2 ), number of decelerations (DEC eff ; loads and acute:chronic workload ratios (ACWR) were calculated and split into low, medium and high groups. Only overuse injuries were included in the analysis to focus on their specific relationship with the load indicators. Generalized estimating equations were applied to analyse the relationship between load indicators and overuse injuries in the subsequent week. In total, 64 overuse injuries were registered. For cumulative loads, results indicated an increased injury risk for higher 2- to 4-weekly loads as indicated by TD, DEC eff , and RPE multiplied by duration. For ACWR, a high ratio for THSR (>1.18) resulted in a higher injury risk. In contrast, a lower injury risk was found when comparing medium ratios for ACC eff (0.87-1.12), DEC eff (0.86-1.12), and RPE x duration (0.85-1.12) to low ratios. Findings demonstrate that mainly external load indicators are associated with increased or decreased injury risk. The monitoring of various load indicators is recommended for injury prevention in professional soccer. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.
Ross Cloak, Andrew Lane, Matthew Wyon
Full Text Available Acute whole body vibration (WBV is an increasingly popular training technique amongst athletes immediately prior to performance and during scheduled breaks in play. Despite its growing popularity, evidence to demonstrate its effectiveness on acute neuromuscular responses is unclear, and suggestions that athlete ability impacts effectiveness warrant further investigation. The purpose of this study was to compare the neuromuscular effects of acute WBV and perceptions of whether WBV is an effective intervention between amateur and professional soccer players. Participants were 44 male soccer players (22 professional and 22 amateur; age: 23.1 ± 3.7 years, body mass: 75.6 ± 8.8 kg and height: 1.77 ± 0.05 m. Participants in each group were randomly assigned to either an intervention of 3 x 60 s of WBV at 40 Hz (8mm peak-to-peak displacement or control group. Peak knee isometric force, muscle activation and post activation potentiation (PAP of the knee extensors along with self-report questionnaire of the perceived benefits of using the intervention were collected. A three-way ANOVA with repeated measures revealed professional players demonstrated a significant 10.6% increase (p < 0.01, Partial Eta2 = 0.22 in peak knee isometric force following acute WBV with no significant differences among amateur players. A significant difference (p < 0.01, Partial Eta2 = 0.16 in PAP amongst professional players following acute WBVT was also reported. No significant differences amongst amateur players were reported across measurements. Results also indicated professional players reported significantly stronger positive beliefs in the effectiveness of the WBV intervention (p < 0.01, Partial Eta2 = 0.27 compared to amateur players. Acute WBV elicited a positive neuromuscular response amongst professional players identified by PAP and improvements in knee isometric peak force as well as perceived benefits of the intervention, benefits not found among amateur players.
Roberto Dantas de Queiroz
Full Text Available OBJECTIVE: to evaluate the return to sport after surgical treatment for pubalgia among 30 professional soccer players and describe the surgical technique used.METHOD: this case series was evaluated by means of a questionnaire and physical examination on 30 male professional soccer players of mean age 24.4 years (range: 18-30. The mean duration of the symptoms was 18.6 months (range: 13-28. The diagnosis was made through clinical investigation, special maneuvers and complementary examinations, by the same examiner. All the patients underwent surgical treatment after conservative treatment failed; all procedures were performed by the same surgeon using the same technique. Nonparametric comparisons were made to investigate the time taken to recover after the surgery, for the patients to return to their sport.RESULTS: five patients evolved with hematoma, with the need to remove the stitches three weeks after the operation because of a small dehiscence at the site of the operative wound. The wound healed completely in all these cases by five weeks after the surgery. Four patients presented dysuria in the first week, but improved in the second postoperative week. The mean time taken to return to training was around eight weeks (range: seven-nine. All the players returned to competitive soccer practice within 16 weeks. When asked about their degree of satisfaction after the operation (satisfied or dissatisfied, taking into consideration their return to the sport, there was 100% satisfaction, and they returned to professional practice at the same competitive level as before the injury. This degree of satisfaction continued to the last assessment, which was made after 36 months of postoperative follow-up.CONCLUSION: the surgical technique presented in this case series, with trapezoidal resection of the pubic symphysis in association with bilateral partial tenotomy of the long adductor, was a fast and effective procedure with a low rate of postoperative
de Queiroz, Roberto Dantas; de Carvalho, Rogério Teixeira; de Queiroz Szeles, Paulo Roberto; Janovsky, César; Cohen, Moisés
Objective to evaluate the return to sport after surgical treatment for pubalgia among 30 professional soccer players and describe the surgical technique used. Method this case series was evaluated by means of a questionnaire and physical examination on 30 male professional soccer players of mean age 24.4 years (range: 18–30). The mean duration of the symptoms was 18.6 months (range: 13–28). The diagnosis was made through clinical investigation, special maneuvers and complementary examinations, by the same examiner. All the patients underwent surgical treatment after conservative treatment failed; all procedures were performed by the same surgeon using the same technique. Nonparametric comparisons were made to investigate the time taken to recover after the surgery, for the patients to return to their sport. Results five patients evolved with hematoma, with the need to remove the stitches three weeks after the operation because of a small dehiscence at the site of the operative wound. The wound healed completely in all these cases by five weeks after the surgery. Four patients presented dysuria in the first week, but improved in the second postoperative week. The mean time taken to return to training was around eight weeks (range: seven–nine). All the players returned to competitive soccer practice within 16 weeks. When asked about their degree of satisfaction after the operation (satisfied or dissatisfied), taking into consideration their return to the sport, there was 100% satisfaction, and they returned to professional practice at the same competitive level as before the injury. This degree of satisfaction continued to the last assessment, which was made after 36 months of postoperative follow-up. Conclusion the surgical technique presented in this case series, with trapezoidal resection of the pubic symphysis in association with bilateral partial tenotomy of the long adductor, was a fast and effective procedure with a low rate of postoperative
Juan Carlos Ávalos Guillén
Full Text Available The purpose of this study was to compare the effect of artificial turf (AT and natural grass (NG on the physical and technical performance of professional soccer players. A total of 17 healthy male soccer players (24.0 ± 4.1 years, height 174 ± 6.1 cm; body weight 73.4 ± 6.3 kg; body fat % 14.2 ± 2.3; VO2max 55.5 ± 5.3 ml/kg/min from a Costa Rican Professional Soccer League club were subjected to different tests in both types of surfaces (technical test, agility test, repeated sprint ability test, and a small-sided game [8 minutes, 32 x 32 meters, 5 vs. 5]. Players were monitored using a GPS in two sessions, separated by 48 hours, during the club’s pre-season. There were no significant differences between the two types of surfaces for the technical, agility, and repeated sprint ability tests. The physiological and kinematic variables analyzed during the small-sided game presented significant differences in average heart rate (NG = 168.5 ± 8.8, AT = 154.8 ± 11.8, p <.001, maximum heart rate (NG = 183.2 ± 8.3, AT = 175.9 ± 10.4, p =.02, body load (NG = 34.3 ± 11.2, AT = 30.5 ± 11.4, p =.03, and total impacts (NG = 230.1 ± 89.5, AT = 194. 8 ± 86.4, p=.03. It is concluded that playing on the natural grass surface caused more impact on physiological and perceived body load in players. In the case of technical variables, it is concluded that there were no statistically significant differences between the two types of surfaces (p <0.05.
Fessi, Mohamed S; Farhat, Fayçal; Dellal, Alexandre; Malone, James J; Moalla, Wassim
The present study aimed to investigate the difference between straight-line (STL) and change of direction (COD) intermittent running exercises in soccer players. Seventeen male professional soccer players performed the agility T-test and 6 intermittent running exercises: 10s at 130% of maximal aerobic speed (MAS) alternated with 10s of rest (10-10), 15s at 120% of MAS alternated with 15s of rest (15-15) and 30s at 110% of MAS alternated with 30s of rest (30-30) both in STL and with COD. All exercises were monitored using a global positioning system. Heart rate was measured during exercises and the rate of perceived exertion (RPE) was collected post-exercise. Delta (Δ) between covered distance in STL and COD exercises at a similar load was calculated and relationships between T-test and Δ distance were analysed. COD intermittent exercises showed a significantly decreased distance covered and an increased number of accelerations, heart rate peak and RPE value compared to STL intermittent exercises at a similar load. High relationships were observed between T-test performance and Δ distance in 10-10 (r = 0.72, P distance in 30-30 (r = -0.37, P = 0.2). Intermittent COD exercises were associated with higher acceleration, heart rate peak and RPE compared to STL during 10-10 and 15-15 exercises. The ability to rapidly change direction is a crucial quality to perform intense sport-specific running in professional soccer players.
Fransson, Dan; Nielsen, Tobias Schmidt; Olsson, Karl
PURPOSE: To examine the skeletal muscle and performance responses across two different exercise training modalities which are highly applied in soccer training. METHODS: Using an RCT design, 39 well-trained male soccer players were randomized into either a speed endurance training (SET; n = 21...... and SSG, respectively, while GLUT-4 protein expression increased (P training improved muscle oxidative capacity and exercise performance more pronouncedly...... than small-sided game training, but comparable responses were in muscle ion transporters and antioxidative capacity in well-trained male soccer players....
Background. The physical demands of field hockey and soccer, based on match analysis, are comparable. As a consequence many exercise scientists and coaches have started to use the same type of field tests for hockey and soccer for the purposes of talent identification and training prescription. The validity of this ...
Soccer in Rwandan high schools can expose players to the risk of injury warranting prevention programmes. The aim of this study was to determine the type, causes, severity and management of injuries among high school soccer players in Rwanda, in order to obtain baseline data for injury prevention programmes.
Briggs, Marc; Cockburn, Emma; Rumbold, Penny; Rae, Glen; Stevenson, Emma; Russell, Mark
This study investigated the energy intake and expenditure of professional adolescent academy-level soccer players during a competitive week. Over a seven day period that included four training days, two rest days and a match day, energy intake (self-reported weighed food diary and 24-h recall) and expenditure (tri-axial accelerometry) were recorded in 10 male players from a professional English Premier League club. The mean macronutrient composition of the dietary intake was 318 ± 24 g·day−1 ...
Sapieja, Klaudia M; Dunn J, G H; Holt, Nicholas L
Although perfectionist orientations have been linked to a variety of cognitive, affective, and behavioral correlates in youth sport, little is known about antecedent factors that may influence adolescent athletes' perfectionist orientations. The purpose of this study was to determine whether perceptions of parenting styles differ as a function of adolescent athletes' perfectionist orientations. A total of 194 male youth soccer players (M age = 13.64 years; SD = 1.51; range, 10.67-16.25 years) completed measures of their perfectionist orientations in sport and of their perceptions of maternal and paternal parenting styles. Scores from the parenting style measure were calculated such that higher scores were reflective of higher parental authoritativeness (as perceived by the athletes). Cluster analyses conducted on perfectionism responses produced independent clusters of unhealthy perfectionists, healthy perfectionists, and nonperfectionists. MANOVA results revealed that both healthy- and nonperfectionists had significantly higher perceptions of maternal and paternal authoritativeness than unhealthy perfectionists (ps parenting may play a role in developing healthy perfectionist orientations (or decrease the likelihood of developing unhealthy perfectionist orientations) in youth sport.
Full Text Available Purpose: To investigate the changes through repeated explosive effort sequences (20+20-m sprint with change of direction, jumping, metabolic response (lactate, as well as the relationship between these variables and fitness qualities (strength and endurance in professional futsal and soccer players. Methods: Male players (n =30, Twelve futsal and twenty soccer players completed three testing sessions. In the first session was measured VO2max on a motorized treadmill. In the second session was measured counter movement jump (CMJ and full squat RM in Smith Machine. Finally, in the third session six repeated-explosive effort sequences (RES was performed. Results: Similar values of lower limbs strength, CMJ height, LAC after RSA test and VO2max (95,12 vs. 94,73; 34,5 vs. 35,9; 13,65 vs. 14,33; 62,78 vs. 62,95 soccer vs. futsal respectively and significant differences when are analysed the loss of performance in velocity (total and between three first and three last and vertical jump height (2,67 vs. 4,4**; 1,28 vs. 2,1*; 2,88 vs. 6,1**; 9,71 vs. 14,3* soccer vs. futsal respectively. Conclusions: Professional futsal and soccer obtain significant differences in speed and vertical jump height (CMJ loss despite having similar values in squat, oxygen consumption, lactate after RSA test and CMJ height. Issue that could be attributed to the characteristics of the sport. This suggests that the volume should be increased oriented ability to perform repeated sprint actions over other type of training aimed at improving aerobic capacity especially at professional level.
Chamari, Karim; Haddad, Monoem; Wong, Del P; Dellal, Alexandre; Chaouachi, Anis
Many of the socio-cultural lifestyle and dietary changes that take place during Ramadan may affect the risk of injury in athletes, but little evidence is available. The aim of the present study was to examine the effects over two consecutive years of the holy month of Ramadan on injury rates in 42 professional players of a Tunisian top-level professional soccer team. Players were retrospectively organized into fasting and non-fasting groups and monitored for 3 months: 4 weeks before Ramadan, during the month of Ramadan (4 weeks), and 4 weeks after Ramadan each year. During Ramadan, training started at 22.00 h. The circumstances (training/match) and mechanism of injury (traumatic/overuse) were recorded. No significant differences between the three periods were observed for weekly mean training load, training strain, training duration, and Hooper's Index (quality of sleep, and quantities of stress, delayed-onset muscle soreness, and fatigue). Compared with non-fasting players, fasters had a lower (P difference in injury rates was observed between fasting and non-fasting players. Nevertheless, the rates of non-contact (6.8 vs. 0.6 and 1.1) and training overuse (5.6 vs. 0.6 and 0.5) injuries were significantly higher in fasting players during the month of Ramadan than before or after Ramadan. In conclusion, Ramadan, along with the corresponding changes in nutritional habits, sleeping schedule, and socio-cultural and religious events, significantly increased overuse and non-contact injuries in fasting players despite the fact that the training load, strain, and duration were maintained.
Gordon, Reno Eron; Kassier, Susanna Maria; Biggs, Chara
Background Poor hydration compromises performance and heightens the risk of heat stress which adolescents are particularly susceptible to as they produce comparatively larger amount of metabolic heat during exercise. This study determined the hydration status and fluid intake of socio-economically disadvantaged, male adolescent soccer players during training. Methods A pilot study was conducted among 79 soccer players (mean age 15.9???0.8?years; mean BMI 20.2???2.1?kg/m2). Hydration status wa...
Harøy, Joar; Clarsen, Ben; Thorborg, Kristian
BACKGROUND: The majority of surveillance studies in soccer have used a time-loss injury definition, and many groin problems result from overuse, leading to gradually increasing pain and/or reduced performance without necessarily causing an absence from soccer training or match play. Thus, the mag......BACKGROUND: The majority of surveillance studies in soccer have used a time-loss injury definition, and many groin problems result from overuse, leading to gradually increasing pain and/or reduced performance without necessarily causing an absence from soccer training or match play. Thus...... surveillance method developed to capture acute and overuse problems. STUDY DESIGN: Descriptive epidemiology study. METHODS: We registered groin problems during a 6-week period of match congestion using the Oslo Sports Trauma Research Center Overuse Injury Questionnaire. A total of 240 players from 15 teams...... for senior male soccer players. CONCLUSION: We found a high prevalence of groin problems among male soccer players during a period with match congestion. Time-loss definition as used in previous injury surveillance studies captured only one-third of the male groin problems registered with the new method...
OʼBrien, James; Finch, Caroline F
To evaluate the perceptions of professional soccer players and staff members toward injury prevention exercise programs (IPEPs). Self-report survey. Four professional soccer teams in 4 different countries. 126 players, coaches, physiotherapists, and fitness coaches were invited to participate, with 72 respondents. Web-based survey detailing perceptions of lower limb (LL) injury susceptibility and seriousness, the value of IPEPs in general, and more specifically the International Federation of Association Football (FIFA) 11+. The vast majority of the respondents believed that professional soccer players are at high risk of LL injuries (93%) and that players should perform evidence-based injury prevention exercises (98%). They also agreed that LL injuries can shorten a player's career (85%), cause physical problems later in life (82%), and negatively impact on team performance (77%). However, perceptions varied across teams regarding which types of injury prevention exercises are effective, who holds responsibility for injury prevention, and when IPEPs should be performed. Specific knowledge of the FIFA 11+ was very low and 47% of respondents believed the program would need modification for use in their team. Players and staff members in professional soccer teams strongly support the use of evidence-based IPEPs. However, perceptions vary considerably between teams regarding which exercises can prevent injuries, who holds the responsibility for injury prevention, and when preventive exercises should be performed. Enhancing the ultimate impact of IPEPs in professional soccer requires a detailed understanding of each team's specific implementation context.
A Los Arcos
Full Text Available The aim of this study was to quantify the seasonal perceived respiratory and muscular training loads (i.e., sRPEres-TL and sRPEmus-TL completed by elite-oriented young professional soccer players. Twentyfour players (20.3 ± 2.0 years belonging to the same reserve team of a Spanish La Liga club participated in this study. Only the players that were available to train for a whole week with the team and also to play the weekly game were considered: Starters, players that participated in the match for at least 45 min and Non- Starters, players that did not participate or played less than 45 minutes in the match. The competitive period was analysed after the division into 5x6-8 week blocks and 35x1 week microcycles. Data were also analysed with respect to number of days before the immediate match. Weekly TL variation across the in-season blocks was trivial-small for both groups except between Block 2 and Block 3 (ES= moderate. Substantial TL differences (ES= small–very likely were found between training days, the TL pattern being a progressive increase up to MD-3 followed by a decrease until MD-1. Except for the match, sRPEres-/sRPEmus-TL was very similar between Starters and Non-Starters. In summary, perceived TL across the season displayed limited variation. Coaches periodized training contents to attain the highest weekly TL 72 hours before the match to progressively unload the players between MD-3 and the match day. The data revealed that the TL arising from the weekly game was solely responsible for the observed higher weekly TL of Starters in comparison with Non-Starters.
Arliani, Gustavo Gonçalves; Belangero, Paulo Santoro; Runco, Jose Luiz; Cohen, Moisés
OBJECTIVE: This study aims to establish a national methodological model for epidemiological studies on professional soccer player injuries and to describe the numerous relevant studies previously published on this topic. INTRODUCTION: The risk of injury in professional soccer is high. However, previous studies of injury risk in Brazil and other countries have been characterized by large variations in study design and data collection methods as well as definitions of injury, standardized diagnostic criteria, and recovery times. METHODS: A system developed by the Union of European Football for epidemiological studies on professional soccer players is being used as a starting point to create a methodological model for the Brazilian Football Association. To describe the existing studies on professional soccer player injuries, we developed a search strategy to identify relevant epidemiological studies. We included the Latin American and Caribbean Center on Health Sciences and Medline databases in our study. RESULTS: We considered 60 studies from Medline and 16 studies from the Latin American and Caribbean Center on Health Sciences in the final analysis. Twelve studies were selected for final inclusion in this review: seven from the Latin American and Caribbean Center on Health Sciences and five from Medline. We identified a lack of uniformity in the study design, data collection methods, injury definitions, standardized diagnostic criteria, and the definition of recovery time. Based on the information contained within these articles, we developed a model for epidemiological studies for the Brazilian Football Association. CONCLUSIONS: There is no uniform model for epidemiological studies of professional soccer injuries. Here, we propose a novel model to be applied for epidemiological studies of professional soccer player injuries in Brazil and throughout the world. PMID:22012041
Gustavo Goncalves Arliani
Full Text Available OBJECTIVE: This study aims to establish a national methodological model for epidemiological studies on professional soccer player injuries and to describe the numerous relevant studies previously published on this topic. INTRODUCTION: The risk of injury in professional soccer is high. However, previous studies of injury risk in Brazil and other countries have been characterized by large variations in study design and data collection methods as well as definitions of injury, standardized diagnostic criteria, and recovery times. METHODS: A system developed by the Union of European Football for epidemiological studies on professional soccer players is being used as a starting point to create a methodological model for the Brazilian Football Association. To describe the existing studies on professional soccer player injuries, we developed a search strategy to identify relevant epidemiological studies. We included the Latin American and Caribbean Center on Health Sciences and Medline databases in our study. RESULTS: We considered 60 studies from Medline and 16 studies from the Latin American and Caribbean Center on Health Sciences in the final analysis. Twelve studies were selected for final inclusion in this review: seven from the Latin American and Caribbean Center on Health Sciences and five from Medline. We identified a lack of uniformity in the study design, data collection methods, injury definitions, standardized diagnostic criteria, and the definition of recovery time. Based on the information contained within these articles, we developed a model for epidemiological studies for the Brazilian Football Association. CONCLUSIONS: There is no uniform model for epidemiological studies of professional soccer injuries. Here, we propose a novel model to be applied for epidemiological studies of professional soccer player injuries in Brazil and throughout the world.
Jones, Rhys M.; Cook, Christian C.; Kilduff, Liam P.; Zoran Milanović; Nic James; Goran Sporiš; Bruno Fiorentini; Fredi Fiorentini; Anthony Turner; Goran Vučković
Aim. The aim of the present study was to investigate the relationship between maximal aerobic capacity (VO2?max) and repeated sprint ability (RSA) in a group of professional soccer players. Methods. Forty-one professional soccer players (age 23 ? 4?yrs, height 180.0 ? 5.3?cm, weight 79.6 ? 5.3?kg) were required to perform tests to assess RSA and VO2?max on two separate days with at least 48?hr rest between testing sessions. Each player performed a treadmill test to determine their VO2?max and...
Hägglund, Martin; Zwerver, Johannes; Ekstrand, Jan
Background: Patellar tendinopathy is common among athletes in jumping sports and in sports with prolonged repetitive stress of the knee extensor apparatus. The epidemiology in soccer is not well described. Purpose: This study was undertaken to investigate and describe the epidemiology of patellar
Donald T. Kirkendall
Full Text Available The rapid rise in female participation in soccer worldwide has not been followed by a corresponding increase in the number of studies biomechanically that target female kicking patterns to determine if differences exist between males and females. The objectives of this study were to examine kinematic instep kicking differences between elite female and male soccer players in dominant and nondominant limbs. Eight elite soccer players, six females and two males, volunteered as subjects in the study. Subjects took a two-step angled approach of 45-60 degrees to a stationary soccer ball positioned between two force platforms and kicked the ball with the instep portion of the foot as hard as possible into netting which was draped from the ceiling. Ball velocity was the dependent variable. We evaluated six additional variables that have previously been shown to be important predictors of instep kicking ball speed. The males generally kicked the ball faster than the females and displayed greater kinematic variables, including maximum toe velocity, ball contact ball velocity, mean toe velocity, mean toe acceleration, and ankle velocity at ball contact, all of which contributed to faster ball speed. There was one exception. One of the elite females kicked faster than the two elite males and demonstrated higher or similar kinematic patterns when compared with the males. Our conclusions were that females do not instep kick the ball as fast as males, but there are exceptions, as our data demonstrates
Full Text Available Youth soccer is thriving in the United States but the coun- try's professional soccer leagues over the past couple decades have had mixed results in terms of commercial viability with some leagues surviving (e.g., MLS and others ceasing (e.g., WUSA. While scholars and practitioners may offer explanations regarding the reasons for the specific challenges facing women's professional soccer leagues, the pre- sent study looked at this subject by examining one group of stakeholders - female elite athletes - and the players’ perceptions of gender in the USA professional soccer program. The findings of this qualitative analysis were concentrated in- to three interconnected themes. The first theme involved the participants' perceptions of role models and their socialization as soccer players. Media images and the invisibility of the female athlete formed the second theme. The third theme was the sexualization of elite female bodies and transgressions of compulsory heterosexuality boundaries. The analysis of the interviews revealed an interesting paradox of elite female athletes using gender to understand sports. The inter- viewed athletes used stereotypical notions of masculinity to increase their legitimacy as elite athletes, while at the same time devaluing the abilities of female coaches by using stereotypical notions of femininity. In addition to discussing the empirical results and interconnected themes, the implications of the findings are also detailed.
Arif Mohammad; Mohammad Ahsan
The purpose of the present research was to compare the level of exercise motivation of male and female soccer players. Secondary purpose of this work was to answer of the question “which gender needs what extend of exercise motivation to perform better in sports?” The method carried out in this study was quantitative in nature and based on the questionnaire study. Population of this research consisted on all male and female soccer players in Rakiraki Public High School, Kings Road, Fiji. Amon...
Arroyo, Marta; Gonzalez-de-Suso, Jose Manuel; Sanchez, Celia; Ansotegui, Laura; Rocandio, Ana M
The purpose of this study was to evaluate body composition and body image (perception and satisfaction) in a group of young elite soccer players and to compare the data with those of a control group (age and BMI matched). Participants were 56 volunteer males whose mean age and BMI were 19.6 (SD 1.3) years and 23.3 (SD 1.1) kg/m2, respectively. Results showed that soccer players have a higher lean mass and lower fat mass than controls. Moreover, body perception (difference between current and actual image) was more accurate in controls than in soccer players, and the results suggest a tendency for soccer players to aspire to have more muscle mass and body fat. Soccer players perceived an ideal image with significantly higher body-fat percentage than their current and actual images. There were no body-dissatisfaction differences between groups, however. Although the results are necessarily limited by the small sample size, the findings should be of interest to coaches of young elite soccer teams.
Koerte, Inga K; Lin, Alexander P; Muehlmann, Marc; Merugumala, Sai; Liao, Huijun; Starr, Tyler; Kaufmann, David; Mayinger, Michael; Steffinger, Denise; Fisch, Barbara; Karch, Susanne; Heinen, Florian; Ertl-Wagner, Birgit; Reiser, Maximilian; Stern, Robert A; Zafonte, Ross; Shenton, Martha E
Soccer is played by more than 250 million people worldwide. Repeatedly heading the ball may place soccer players at high risk for repetitive subconcussive head impacts (RSHI). This study evaluates the long-term effects of RSHI on neurochemistry in athletes without a history of clinically diagnosed concussion, but with a high exposure to RSHI. Eleven former professional soccer players (mean age 52.0±6.8 years) and a comparison cohort of 14 age- and gender-matched, former non-contact sport athletes (mean age 46.9±7.9 years) underwent 3T magnetic resonance spectroscopy (MRS) and neurocognitive evaluation. In the soccer players a significant increase was observed in both choline (Cho), a membrane marker, and myo-inositol (ml), a marker of glial activation, compared with control athletes. Additionally, ml and glutathione (GSH) were significantly correlated with lifetime estimate of RSHI within the soccer group. There was no significant difference in neurocognitive tests between groups. Results of this study suggest an association between RSHI in soccer players and MRS markers of neuroinflammation, suggesting that even subconcussive head impacts affect the neurochemistry of the brain and may precede neurocognitive changes. Future studies will need to determine the role of neuroinflammation in RSHI and the effect on neurocognitive function.
Harøy, Joar; Clarsen, Ben; Thorborg, Kristian; Hölmich, Per; Bahr, Roald; Andersen, Thor Einar
The majority of surveillance studies in soccer have used a time-loss injury definition, and many groin problems result from overuse, leading to gradually increasing pain and/or reduced performance without necessarily causing an absence from soccer training or match play. Thus, the magnitude of groin problems in soccer has probably been underestimated in previous studies based on traditional injury surveillance methods. To investigate the prevalence of groin problems among soccer players of both sexes and among male soccer players at different levels of play through a new surveillance method developed to capture acute and overuse problems. Descriptive epidemiology study. We registered groin problems during a 6-week period of match congestion using the Oslo Sports Trauma Research Center Overuse Injury Questionnaire. A total of 240 players from 15 teams across different levels of play and from both sexes were included, and they responded to the weekly questionnaire. We calculated the average weekly prevalence of all groin problems and substantial groin problems. Of the 240 players, 112 male players (59%) and 20 female players (45%) reported at least 1 episode of groin problems. The average weekly prevalence of any groin problem and substantial groin problem for all male players was 29% (range, 23%-32% across different levels) and 10% (7%-13%), respectively. Elite male players had an increased risk of experiencing groin problems (odds ratio: 3.1, 95% CI: 1.5-6.4, P = .03) compared with elite female players. There was no difference in the risk of experiencing groin problems among elite, subelite, and amateur male players. For substantial problems, there was no difference between elite male and elite female players or among levels of play for senior male soccer players. We found a high prevalence of groin problems among male soccer players during a period with match congestion. Time-loss definition as used in previous injury surveillance studies captured only one
Rhys M. Jones
Full Text Available Aim. The aim of the present study was to investigate the relationship between maximal aerobic capacity ( and repeated sprint ability (RSA in a group of professional soccer players. Methods. Forty-one professional soccer players (age yrs, height cm, weight kg were required to perform tests to assess RSA and on two separate days with at least 48 hr rest between testing sessions. Each player performed a treadmill test to determine their and a test for RSA involving the players completing m sprints (turn after 20 m with 20 s active recovery between each sprint. Results. There was a significant negative correlation between body mass normalised and mean sprint time ( (; and total sprint time ( (, . Conclusion. Results of the current study indicate that is one important factor aiding soccer players in the recovery from repeated sprint type activities.
Andrews, Michael C; Itsiopoulos, Catherine
Athletes require sufficient nutrition knowledge and skills to enable appropriate selection and consumption of food and fluids to meet their health, body composition, and performance needs. This article reports the nutrition knowledge and dietary habits of male football (soccer) players in Australia. Players age 18 years and older were recruited from 1 A-League club (professional) and 4 National Premier League clubs (semiprofessional). No significant difference in general nutrition knowledge (GNK; 54.1% ± 13.4%; 56.8% ± 11.7%; M ± SD), t(71) = -0.91, p = .37, or sports nutrition knowledge (SNK; 56.9% ± 15.5%; 61.3% ± 15.9%), t(71) = -1.16, p = .25) were noted between professional (n = 29) and semiprofessional (n = 44) players. In general, players lacked knowledge in regard to food sources and types of fat. Although nutrition knowledge varied widely among players (24.6-82.8% correct responses), those who had recently studied nutrition answered significantly more items correctly than those who reported no recent formal nutrition education (62.6% ± 11.9%; 54.0% ± 11.4%), t(67) = 2.88, p = .005). Analysis of 3-day estimated food diaries revealed both professionals (n = 10) and semiprofessionals (n = 31) consumed on average less carbohydrate (3.5 ± 0.8 gC/kg; 3.9 ± 1.8 gC/kg) per day than football-specific recommendations (FIFA Medical and Assessment Research Centre [F-MARC]: 5-10 gC/kg). There was a moderate, positive correlation between SNK and carbohydrate intake (n = 41, ρ = 0.32, p = .04), indicating that players who exhibited greater SNK had higher carbohydrate intakes. On the basis of these findings, male football players in Australia would benefit from nutrition education targeting carbohydrate and fat in an attempt to improve nutrition knowledge and dietary practices.
Nawabi, Danyal H; Cro, Suzie; Hamid, Imran P; Williams, Andy
Meniscectomy is frequently performed in elite soccer athletes to allow return to a high level of performance as early as possible. Although lateral meniscectomy is known to have more serious long-term sequelae than medial meniscectomy, little is known about the effect of lateral meniscectomy on the time to return to play during the early recovery phase in professional soccer players. Lateral meniscectomy results in longer times to return to preinjury level of competition and a higher incidence of adverse outcomes compared with medial meniscectomy in elite professional soccer players. Cohort study; Level of evidence, 3. A single-surgeon database containing the injury history and operative details of elite soccer athletes from 2005 to 2009 was used to identify players who had undergone an isolated partial lateral or medial meniscectomy. The time to return to preinjury level of competition, the incidence of adverse events during early recovery, and the need for further arthroscopy were recorded. Time to return to play was analyzed by using the Kaplan-Meier method. A multivariate analysis was used to control for age, location of meniscectomy, percentage of meniscus excised, and type of tear. Ninety soccer players were identified, of which 42 had a lateral meniscectomy and 48 had a medial meniscectomy. The median time to return to play, to the nearest week, was longer in the lateral group than the medial group (7 vs 5; P soccer athletes. Lateral meniscectomy has a higher incidence of adverse events in the early recovery period, including pain/swelling and the need for further arthroscopy. It is also associated with a significantly lower rate of return to play. These findings form the basis of an important discussion that must be had with player and club before a lateral meniscectomy is performed in elite soccer athletes. © 2014 The Author(s).
Marcos, Michaelides A; Koulla, Parpa M; Anthos, Zacharia I
Marcos, MA, Koulla, PM, and Anthos, ZI. Preseason maximal aerobic power in professional soccer players among different divisions. J Strength Cond Res 32(2): 356-363, 2018-The purpose of this study was to examine and compare the anthropometric, maximal oxygen uptake (V[Combining Dot Above]O2max), and positional differences of first division (D1) professional football players from players of second (D2) and third (D3) divisions in Cyprus football leagues. Four hundred twenty-one professional male football players participated in this study. All subjects underwent anthropometric and body composition evaluation. In addition, they performed an incremental cardiopulmonary exercise testing (CPET) on a treadmill for V[Combining Dot Above]O2max evaluation. The results were analyzed using 1-way analysis of variance, between subjects design revealing significant effects among the divisions. Tukey's honest significant difference (HSD) tests demonstrated that players from D1 scored significantly higher on V[Combining Dot Above]O2max and lasted significantly longer on the treadmill than participants of D2 and D3 (p ≤ 0.05). Similar findings were demonstrated when D2 was contrasted against D3 players. Goalkeepers, defenders, and forwards demonstrated significantly higher anthropometric measurements, whereas wingers and midfielders demonstrated significantly higher V[Combining Dot Above]O2max (p ≤ 0.05) than goalkeepers and defenders. The findings of this study clearly demonstrated that cardiovascular fitness, as determined by CPET, is an important fitness parameter that differentiates professional football players who play at a more advanced level. This could be attributed to the different seasonal schedules that allow for longer transition time for lower division players and thus favoring greater detraining effects. Emphasis should be given by fitness professionals on transition period training to minimize the detraining effects especially in lower divisions.
Full Text Available Introduction. The aims of the present study were to determine the activity profiles of a large sample of Polish Premier League soccer players during elite-standard soccer matches depending on their position on the pitch and the intensity range of physical activity. Material and methods. The study sample comprised 1,178 players in 5 outfield positions: external defenders (ED, n = 289, central defenders (CD, n = 307, central midfield players (CM, n = 327, external midfield players (EM, n = 152, and forwards (F, n = 103. Altogether, 81 Polish League games held during four domestic seasons (2010-2011, 2011-2012, 2012-2013, and 2013-2014 were used in the analysis. A semi-automatic computerised player tracking system (Amisco Pro®, version 1.0.2, Nice, France was applied to create the match activity profiles of the teams. Results. The results of statistical analysis revealed that the average total distance covered by all the players (n = 1,178 was 11,313 ± 852 m. With respect to the players’ position on the pitch, the central midfielders travelled the longest average distance (11,894 ± 765 m during the game. The longest distance was covered in the V1 intensity range (62%, followed by V2 (15%, V3 (10%, V4 (8%, V5 (3%, and V6 (2%. Conclusions. The objective of this study was to verify the differences among playing positions and to quantify the demands placed on elite Polish soccer players in each individual position during match play. While analysing elite-level match play in terms of the overall distance covered in different categories of intensity, we found a number of statistically significant differences between different playing positions. The data presented in this study can be regarded as norms for elite soccer players, serve for present and future comparison, and represent the scientific basis for developing position-specific conditioning/training protocols in soccer.
van Doormaal, Mitchell C M; van der Horst, Nick; Backx, Frank J G; Smits, Dirk-Wouter; Huisstede, Bionka M A
In soccer, although hamstring flexibility is thought to play a major role in preventing hamstring injuries, the relationship between hamstring flexibility and hamstring injuries remains unclear. To investigate the relationship between hamstring flexibility and hamstring injuries in male amateur soccer players. Case-control study; Level of evidence, 3. This study included 450 male first-class amateur soccer players (mean age, 24.5 years). Hamstring flexibility was measured by performing the sit-and-reach test (SRT). The relationship between hamstring flexibility and the occurrence of hamstring injuries in the following year, while adjusting for the possible confounding effects of age and previous hamstring injuries, was determined with a multivariate logistic regression analysis. Of the 450 soccer players, 21.8% reported a hamstring injury in the previous year. The mean (±SD) baseline score for the SRT was 21.2 ± 9.2 cm. During the 1-year follow-up period, 23 participants (5.1%) suffered a hamstring injury. In the multivariate analysis, while adjusting for age and previous injuries, no significant relationship was found between hamstring flexibility and hamstring injuries ( P = .493). In this group of soccer players, hamstring flexibility (measured with the SRT) was not related to hamstring injuries. Age and previous hamstring injuries as possible confounders did not appear to influence this relationship. Other etiological factors need to be examined to further elucidate the mechanism of hamstring injuries.
Jaspers, Arne; Brink, Michel S.; Probst, Steven G M; Frencken, Wouter G. P.; Helsen, Werner F.
Background In professional senior soccer, training load monitoring is used to ensure an optimal workload to maximize physical fitness and prevent injury or illness. However, to date, different training load indicators are used without a clear link to training outcomes. Objective The aim of this
Jaspers, Arne; Kuyvenhoven, Jurian P; Staes, Filip; Frencken, Wouter G P; Helsen, Werner F; Brink, Michel S
OBJECTIVES: Research in professional soccer focusing on the relevance of external and internal load indicators for injury prevention is scarce. This study examined the relationship between load indicators and overuse injuries. DESIGN: Prospective cohort study. METHODS: Data were collected from 35
Gouttebarge, Vincent; Backx, Frank J. G.; Aoki, Haruhito; Kerkhoffs, Gino M. M. J.
Evidence on the prevalence of symptoms related to distress, anxiety/depression or substance abuse/dependence, - typically referred to as symptoms of common mental disorders (CMD) - is lacking in European professional football (soccer). The aims of the present study were to investigate the prevalence
Horst, Nick Van Der; Priesterbach, Annique; Backx, Frank|info:eu-repo/dai/nl/069615039; Smits, Dirk-Wouter|info:eu-repo/dai/nl/207320462
Objective: This study investigated the hamstring-and-lower-back flexibility (HLBF) of male adult amateur soccer players, using the sit-and-reach test (SRT), with a view to obtaining population-based reference values and to determining whether SRT scores are associated with player characteristics.
Beijsterveldt, A.M.C. van; Port, L.G.L. van de; Vereijken, A.J.; Backx, F.J.C.
Hamstring injuries are common injuries in soccer players. In view of the high incidence and the serious consequences, identifying risk factors related to hamstring injuries is essential. The aim of this systematic review was therefore to identify risk factors for hamstring injuries in male adult
Herrero, Helena; Salinero, Juan José; Del Coso, Juan
Soccer is the most popular sport worldwide, with about 265 million players, both professionals and amateurs. Most research investigating soccer injuries has focused on professional players because they have greater exposure time, but most soccer players are at the recreational level. To undertake a retrospective epidemiological study of the injuries sustained in Spanish amateur soccer during the 2010-2011 season. Descriptive epidemiological study. Any injuries incurred by the 134,570 recreational soccer players (aged 18-55 years) registered with the Spanish Football Federation were reported to the federation's medical staff. A standardized medical questionnaire, based on the Fédération International de Football Association (FIFA) Medical and Research Centre (F-MARC) consensus for collection procedures in studies of soccer injuries, was used to classify the injury according to type, severity, location, and treatment. A total of 15,243 injuries were reported, with an average of 0.11 injuries per player and per year. From the total number of injuries, 67.2% were classified as injuries that resulted in time loss, while the remaining 32.7% were injuries that required medical attention. Most injuries led to a minimum of 1 competitive match being missed (87%), and only 2.5% were recurrent injuries. The rate of injuries per 1000 hours of play was double during games (1.15/1000 hours) compared with during training (0.49/1000 hours). From the total number of injuries reported, 7.7% corresponded to goalkeepers, 24.2% to forwards, 33.8% to defenders, and 34.3% to midfielders. The knee (29.9%) and ankle joints (12.4%) were the most common body locations injured, while ligament sprains and ruptures accounted for 32.1% of the total injuries attended. Older amateur players (age ≥30 years) had a greater number of injuries per year and per 1000 hours of play than their younger counterparts. The risk of injury in amateur soccer is lower than that previously reported in
Briggs, Marc A; Cockburn, Emma; Rumbold, Penny L S; Rae, Glen; Stevenson, Emma J; Russell, Mark
This study investigated the energy intake and expenditure of professional adolescent academy-level soccer players during a competitive week. Over a seven day period that included four training days, two rest days and a match day, energy intake (self-reported weighed food diary and 24-h recall) and expenditure (tri-axial accelerometry) were recorded in 10 male players from a professional English Premier League club. The mean macronutrient composition of the dietary intake was 318 ± 24 g·day(-1) (5.6 ± 0.4 g·kg(-1) BM) carbohydrate, 86 ± 10 g·day(-1) (1.5 ± 0.2 g·kg(-1) BM) protein and 70 ± 7 g·day(-1) (1.2 ± 0.1 g·kg(-1) BM) fats, representing 55% ± 3%, 16% ± 1%, and 29% ± 2% of mean daily energy intake respectively. A mean daily energy deficit of -1302 ± 1662 kJ (p = 0.035) was observed between energy intake (9395 ± 1344 kJ) and energy expenditure (10679 ± 1026 kJ). Match days (-2278 ± 2307 kJ, p = 0.012) and heavy training days (-2114 ± 2257 kJ, p = 0.016) elicited the greatest deficits between intake and expenditure. In conclusion, the mean daily energy intake of professional adolescent academy-level soccer players was lower than the energy expended during a competitive week. The magnitudes of these deficits were greatest on match and heavy training days. These findings may have both short and long term implications on the performance and physical development of adolescent soccer players.
Marc A. Briggs
Full Text Available This study investigated the energy intake and expenditure of professional adolescent academy-level soccer players during a competitive week. Over a seven day period that included four training days, two rest days and a match day, energy intake (self-reported weighed food diary and 24-h recall and expenditure (tri-axial accelerometry were recorded in 10 male players from a professional English Premier League club. The mean macronutrient composition of the dietary intake was 318 ± 24 g·day−1 (5.6 ± 0.4 g·kg−1 BM carbohydrate, 86 ± 10 g·day−1 (1.5 ± 0.2 g·kg−1 BM protein and 70 ± 7 g·day−1 (1.2 ± 0.1 g·kg−1 BM fats, representing 55% ± 3%, 16% ± 1%, and 29% ± 2% of mean daily energy intake respectively. A mean daily energy deficit of −1302 ± 1662 kJ (p = 0.035 was observed between energy intake (9395 ± 1344 kJ and energy expenditure (10679 ± 1026 kJ. Match days (−2278 ± 2307 kJ, p = 0.012 and heavy training days (−2114 ± 2257 kJ, p = 0.016 elicited the greatest deficits between intake and expenditure. In conclusion, the mean daily energy intake of professional adolescent academy-level soccer players was lower than the energy expended during a competitive week. The magnitudes of these deficits were greatest on match and heavy training days. These findings may have both short and long term implications on the performance and physical development of adolescent soccer players.
Briggs, Marc A.; Cockburn, Emma; Rumbold, Penny L. S.; Rae, Glen; Stevenson, Emma J.; Russell, Mark
This study investigated the energy intake and expenditure of professional adolescent academy-level soccer players during a competitive week. Over a seven day period that included four training days, two rest days and a match day, energy intake (self-reported weighed food diary and 24-h recall) and expenditure (tri-axial accelerometry) were recorded in 10 male players from a professional English Premier League club. The mean macronutrient composition of the dietary intake was 318 ± 24 g·day−1 (5.6 ± 0.4 g·kg−1 BM) carbohydrate, 86 ± 10 g·day−1 (1.5 ± 0.2 g·kg−1 BM) protein and 70 ± 7 g·day−1 (1.2 ± 0.1 g·kg−1 BM) fats, representing 55% ± 3%, 16% ± 1%, and 29% ± 2% of mean daily energy intake respectively. A mean daily energy deficit of −1302 ± 1662 kJ (p = 0.035) was observed between energy intake (9395 ± 1344 kJ) and energy expenditure (10679 ± 1026 kJ). Match days (−2278 ± 2307 kJ, p = 0.012) and heavy training days (−2114 ± 2257 kJ, p = 0.016) elicited the greatest deficits between intake and expenditure. In conclusion, the mean daily energy intake of professional adolescent academy-level soccer players was lower than the energy expended during a competitive week. The magnitudes of these deficits were greatest on match and heavy training days. These findings may have both short and long term implications on the performance and physical development of adolescent soccer players. PMID:26445059
Full Text Available Abstract The complete isolated rupture of the popliteus tendon has been described as a rare injury and this report describes the case of a 31-year-old soccer player who sustained a partial rupture of the popliteus tendon during a game. The injury was suspected clinically and at MRI but confirmed only by the arthroscopic examination. The treatment consisted in open debridment with no tendon repair or augmentation. Seven weeks post-operation the patient was symptom-free and returned to competitive professional soccer at the same preinjury level. The clinical and arthroscopic findings of the case reported suggest a possible overuse disease with degenerative expression.
Fransson, Dan; Nielsen, Tobias Schmidt; Olsson, Karl
PURPOSE: To examine the skeletal muscle and performance responses across two different exercise training modalities which are highly applied in soccer training. METHODS: Using an RCT design, 39 well-trained male soccer players were randomized into either a speed endurance training (SET; n = 21...... analysed for metabolic enzyme activity and muscle protein expression. Moreover, the Yo-Yo Intermittent Recovery level 2 test (Yo-Yo IR2) was performed. RESULTS: Muscle CS maximal activity increased (P ...% in SET and SSG, respectively, while GLUT-4 protein expression increased (P training improved muscle oxidative capacity and exercise performance more...
Full Text Available Objectives: To evaluate oral health, the determinants of oral health and the effect of oral health on well-being, training and performance of professional soccer players in Thailand. Methods: Twenty-nine professional soccer players in Phitsanulok FC, Thailand. Oral examination about DMFT, Quigley & Hein plaque index (PI, Löe & Silness gingival index, World Health Organization malocclusion index, pocket depth, TMJ examination and history of dental trauma were recorded. Impact of oral health on athletic performance and training was assessed using OIDP Results: The results demonstrated high levels of poor oral health including dental caries (84%, mean DMFT= 10.08 (D=8.0, M=0.84 and F=1.24, dental attrition (60% and periodontal pocket (36%. Thirty percent of all players presented bruxism and 10 % with severe malocclusion. More than 40% of athletes were ‘bothered’ by their oral health with 28% reporting an impact on quality of life and 18% on training and performance. Conclusion: The oral health of professional soccer players Thai was poor with a resulting substantial negative impact on well-being, training and performance. As oral health is an important element of overall health and well-being, health promotion and disease prevention interventions are urgently required to optimise soccer player performance.DOI: 10.14693/jdi.v23i1.633
Full Text Available Anthropometric and physiological characteristics of professional soccer players per playing position have been studied extensively in order to determine their relevance in competitions. However, comparing methods to assess body composition is uncommon for Costa Rican soccer players. Purpose: compare body composition using Dual Energy X-Ray Absorptiometry (DEXA and the skinfold method in Costa Rican professional soccer players. Methods: 106 Costa Rican professional soccer players, 24.53 ± 4.77 years of age, participated in the study. Results: On average body fat was 13.34 ± 4.1 %, fat free mass 62.1±5.5 kg and bone mineral content 3.6 ± 0.4 g/cm2 using DEXA, while body fat recorded using the skindfold method was 12.58 ± 3.0 %. When comparing body fat using both methods significant differences were recorded (p=0.005. In addition, there were differences on fat free mass by extremity in the upper right component (p=0.001 and lower (p=0.037 extremities. Fat free mass per playing position showed differences in the arms (p<0.05. There was a strong positive correlation (r=0.75, p < 0.001 between body fat obtained using DEXA and the skinfold methods. Conclusion: When comparing fat percentages using both methods significant differences were recorded. Body fat measured with both methods was very similar; consequently, both techniques may be used in this population.
Hölmich, Per; Thorborg, Kristian; Dehlendorff, Christian
BACKGROUND: Groin injuries cause major problems in the football codes, as they are prevalent and lead to prolonged symptoms and high recurrence. The aim of the present study was to describe the occurrence and clinical presentation of groin injuries in a large cohort of sub-elite soccer players...... during a season. METHODS: Physiotherapists allocated to each of the participating 44 soccer clubs recorded baseline characteristics and groin injuries sustained by a cohort of 998 sub-elite male soccer players during a full 10-month season. All players with groin injuries were examined using the clinical...... entity approach, which utilises standardised reproducible examination techniques to identify the injured anatomical structures. The exposure time and the injury time were also recorded. Injury time was analysed using multiple regression on the log of the injury times as the data were highly skewed...
Micheli, Matteo Levi; Pagani, Luca; Marella, Mario; Gulisano, Massimo; Piccoli, Antonio; Angelini, Fabrizio; Burtscher, Martin; Gatterer, Hannes
Bioelectrical-impedance standards (resistance, reactance, and phase angle) are well established for the normal population or in the clinical setting and are considered indicators for cell mass, cell function, and hydration status. However, such standards do not exist for the male soccer population. Therefore, the goal of the current investigation was to provide a set of bioelectrical-impedance data of a large sample of soccer players with different performance levels. A sample of 893 players, registered in all Italian soccer divisions, was divided into 5 groups according to their performance level. Whole-body impedance measurements were performed during the first half of the competitive period. Besides estimation of body composition, bioelectrical-impedance vector analysis (BIVA) was performed. BIVA does not depend on equations and displays differences in hydration and body-cell mass (BCM). Individual vectors can be classified by using the 50%, 75%, and 95% tolerance ellipse. In comparison with the other divisions and the normal population, the mean vector of the elite level showed a shift to the left (P angles, BCM, and fat-free mass. In conclusion, soccer players belong to a specific population. Muscle mass and function, as indicated by BCM and phase angle, increase with increasing performance level. The soccer-specific tolerance ellipses might be used for classifying individual vectors and to define target regions for low-level players.
Mazuquin, B F; Dela Bela, L F; Pelegrinelli, A R M; Dias, J M; Carregaro, R L; Moura, F A; Selfe, J; Richards, J; Brown, L E; Cardoso, J R
Soccer matches consist of a variety of different activities, including repeated sprints. Time to attain velocity (TTAV), load range (LR) and the torque-angle-velocity relationship (TAV 3D ) represent an important measurement of muscle performance, however there are few related studies. The aim of this study was to compare these outcomes between soccer players of different age category. 17 professional (PRO) and 17 under-17 (U17) soccer players were assessed for concentric knee flexion/extension at 60, 120 and 300°/s. For the extensor muscles, differences were found in favor of the U17 group for TTAV and LR outcomes at 120°/s, however, the PRO group maintained higher torques in both movement directions in comparison to the U17 in TAV 3D evaluation. These results suggest that muscle performance of the PRO group is more efficient than the U17 group. © Georg Thieme Verlag KG Stuttgart · New York.
Ljach, V; Witkowski, Z; Gutnik, B; Samovarov, A; Nash, D
Development of skill in young soccer players relies on progressive improvement in different professionally important sensorimotor cognitive abilities. Development of seven leading abilities was based on the results of 23 tests provided for experimental and control groups. 600 elite young soccer players of both sexes, ages 11 to 19 years, were assessed over a period of 4 years. Experimental groups were given different exercises to aid development of selected abilities. At the end of the monitoring period, the experimental groups demonstrated a significant improvement in contrast to the control groups, and the greatest improvements in different test performances were observed in the 11- to 13-year-olds. The test-retest ata show the testing process to be reliable. The study provides standard pedagogical models and data for trainers, coaches, and researchers working with young soccer players. Future research on talent identification and selection should adopt amultidimensional approach.
Full Text Available The aim of this study was to investigate maximum aerobic power (VO2 max and anaerobic threshold (AT as determinants of training status among professional soccer players. Twelve professional 1st team British male soccer players (age: 26.2 ± 3.3 years, height: 1.77 ± 0.05 m, body mass: 79.3 ± 9.4 kg agreed to participate in the study and provided informed consent. All subjects completed a combined test of anaerobic threshold (AT and maximum aerobic power on two occasions: Test 1 following 5 weeks of low level activity at the end of the off-season and Test 2 immediately following conclusion of the competitive season. AT was assessed as both lactate threshold (LT and ventilatory threshold (VT. There was no change in VO2 max between Test 1 and Test 2 (63.3 ± 5.8 ml·kg-1·min-1 vs. 62.1 ± 4.9 ml·kg-1·min-1 respectively, however, the duration of exercise tolerance (ET at VO2 max was significantly extended from Test 1 to Test 2 (204 ± 54 vs. 228 ± 68 s respectively (P<0.01. LT oxygen consumption was significantly improved in Test 2 versus Test 1 (P<0.01 VT was also improved (P<0.05. There was no significant difference in VO2 (ml·kg-1·min-1 corresponding to LT and VT. The results of this study show that VO2 max is a less sensitive indicator to changes in training status in professional soccer players than either LT or VT.
Full Text Available Purpose. The aim of the study was to compare the morphological characteristics of experienced futsal players with professional soccer players. Methods. The research sample included 22 university futsal players and 22 professional soccer players. Parameters including body height and mass, skinfold thicknesses of the trunk and extremities, lower limb length, trunk width, humerus and femur bone breadths, and the circumferences of the chest, hips, thighs, and calves were used to calculate various somatic indices. Somatotyping was performed using the Heath–carter method. Differences in the characteristics between the futsal and soccer players were analyzed using Student’s t test. Intragroup analysis was also performed on futsal players depending on player position and compared with the arithmetic means and standard deviations of all variables of the entire sample. Results. compared with their soccer-playing peers, the futsal players were shorter, weighed less, had shorter lower limbs, narrower hips, and smaller hip circumference and bone breadth values. In contrast, higher levels of body fat and endomorphy were noted in this group. The proportion of mesomorphs and ectomorphs were similar in both groups. Futsal goalkeepers were differentiated by greater subcutaneous adiposity and body mass. Defenders had the slimmest body shape, with relatively narrower shoulders and hips, smaller bone breadths, and lower levels of adiposity. The body build of wingers was slightly larger. Pivoters were characterized by greater body height and larger values for the characteristics measuring the lateral trunk dimensions. Conclusions. The observed morphological differences between futsal and soccer players were mainly in body height and height-associated characteristics. This indicates that no specialized approach in futsal recruitment is currently used. This points to the need to develop a specialized approach in the player recruitment stage, as the tactical and
Devlin, Brooke L; Leveritt, Michael D; Kingsley, Michael; Belski, Regina
Sports nutrition professionals aim to influence nutrition knowledge, dietary intake and body composition to improve athletic performance. Understanding the interrelationships between these factors and how they vary across sports has the potential to facilitate better-informed and targeted sports nutrition practice. This observational study assessed body composition (DXA), dietary intake (multiple-pass 24-hr recall) and nutrition knowledge (two previously validated tools) of elite and subelite male players involved in two team-based sports; Australian football (AF) and soccer. Differences in, and relationships between, nutrition knowledge, dietary intake and body composition between elite AF, subelite AF and elite soccer players were assessed. A total of 66 (23 ± 4 years, 82.0 ± 9.2 kg, 184.7 ± 7.7 cm) players participated. Areas of weaknesses in nutrition knowledge are evident (57% mean score obtained) yet nutrition knowledge was not different between elite and subelite AF and soccer players (58%, 57% and 56%, respectively, p > .05). Dietary intake was not consistent with recommendations in some areas; carbohydrate intake was lower (4.6 ± 1.5 g/kg/day, 4.5 ± 1.2 g/kg/day and 2.9 ± 1.1 g/kg/day for elite and subelite AF and elite soccer players, respectively) and protein intake was higher (3.4 ± 1.1 g/kg/day, 2.1 ± 0.7 g/kg/day and 1.9 ± 0.5 g/kg/day for elite and subelite AF and elite soccer players, respectively) than recommendations. Nutrition knowledge was positively correlated with fat-free soft tissue mass (n = 66; r2 = .051, p = .039). This insight into known modifiable factors may assist sports nutrition professionals to be more specific and targeted in their approach to supporting players to achieve enhanced performance.
Cross, Kevin M; Gurka, Kelly K; Saliba, Susan; Conaway, Mark; Hertel, Jay
Thigh muscles strains are among the most common injuries in high school soccer for both males and females. Similar results have been reported among collegiate soccer players, specifically for hamstring strains. In collegiate soccer, males have a higher injury rate than women although they share common injury characteristics. Currently, no studies exist comparing the injury rate or injury characteristics of thigh muscle strains between sexes playing high school soccer. To compare thigh muscle strain injury rates and injury event characteristics among sexes participating in high school soccer. Descriptive Epidemiology Study Setting: 100 nationally representative high schools that participated in the High School Sports-Related Injury Surveillance System, RIO. High school soccer athletes who had a thigh muscle strain. Injury rates of thigh muscle strains were calculated between sexes. The occurrence of the following variables during a thigh muscle injury were compared between sexes: grade level, age, level of play, event type, time of practice, time of competition, basic injury mechanism, soccer activity, player position, field location, practice type, time of season. Males had a lower injury rate of thigh muscle strains during competition than females. (RR=0.66; 95% CI, 0.47, 0.93) No differences between sexes existed in the distribution of first-time or recurrent event characteristics. When combining sexes, recurrent strains (93%) occurred more frequently on the offensive side of the field than first-time strains (59%), Phigh school soccer players.
Fousekis, Konstantinos; Tsepis, Elias; Vagenas, George
Ankle sprain is an extremely common injury in soccer players. Despite extensive research, the intrinsic cause of this injury under noncontact conditions remains unclear. To identify intrinsic risk factors for noncontact ankle sprains in professional soccer players. Cohort study; Level of evidence, 2 One hundred professional soccer players were assessed in the preseason for potential risk factors of noncontact ankle sprains. The assessment included (A) ankle joint asymmetries (right-left) in isokinetic muscle strength, flexibility, proprioception, and stability; (B) somatometric asymmetries; (C) previous injuries; and (D) lateral dominance traits. Noncontact ankle sprains were prospectively recorded and diagnosed for a full competition period (10 months). Seventeen of the players sustained at least 1 noncontact ankle sprain. Logistic regression revealed that players with (A) eccentric isokinetic ankle flexion strength asymmetries (odds ratio [OR] = 8.88; 95% confidence interval [CI], 1.95-40.36, P = .005), (B) increased body mass index (OR = 8.16; 95% CI, 1.42-46.63, P = .018), and (C) increased body weight (OR = 5.72; 95% CI, 1.37-23.95, P = .017 ) each had a significantly higher risk of a noncontact ankle sprain. A trend for younger players (OR = 0.28; 95% CI, 0.061-1.24, P = .092) and for players with ankle laxity asymmetries (OR = 3.38; 95% CI, 0.82-14.00, P = .093) to be at greater risk for ankle sprain was also apparent to the limit of statistical significance (.05 sprains in professional soccer players. Age and asymmetries in ankle laxity are potential factors worth revisiting, as there was an indication for younger players and players with ankle instability to be at higher risk for ankle injury. Proper preseason evaluation may improve prevention strategies for this type of injury in soccer.
Quagliarella, Livio; Sasanelli, Nicola; Belgiovine, Giuseppe; Accettura, Domenico; Notarnicola, Angela; Moretti, Biagio
The Counter Movement Jump (CMJ) is widely used as a field test to evaluate the muscular explosive power of lower limbs in various sports, including soccer. The aim of the present study was to verify the possibility to discriminate the effect of training level and age on young adult male soccer players, adopting the flight time, the peak force, or the peak power obtained from a countermovement jump. One hundred and twenty three young male soccer players were enrolled in the study; the participants were split into groups according to Tanner's stages (pre- and post-pubertal) and training level (high and low activity). A piezoelectric force plate was used to acquire the ground reaction force used to calculate the flight time, the peak value of the vertical component of the ground reaction force, and the peak value of the developed power. As expected, the best performances were obtained by the post pubertal highly-trained soccer players. All performance parameters presented statistically significant differences between ages, while only the flight time exhibited statistically significant differences between training levels. After normalization of the experimental data to body height and weight, there were no statistical differences between ages; statistically significant differences were found only for the flight time and for peak power between training levels. The flight time was the parameter more sensitive to detect differences in the jump performance related to training and age. Adopting a normalization procedure it was possible to highlight that only the flight time and the peak power are sensitive to training effects on young adult male soccer players.
Morcillo, Jose A; Jiménez-Reyes, Pedro; Cuadrado-Peñafiel, Victor; Lozano, Emilio; Ortega-Becerra, Manuel; Párraga, Juan
This study analyzed the acute metabolic and mechanical responses to a specific repeated sprint ability (RSA) test. Eighteen male professional soccer players from a team of the First Division of Spanish National League participated. A 12 × 30-m RSA test with 30-second recovery together with countermovement jump test (CMJ) pre a post RSA test was performed. Mechanical responses (i.e., height performance in CMJ and speed loss) and metabolic responses (i.e., blood lactate and ammonia concentrations) were measured before and after exercise. A related sample t-test was used to analyze CMJ height pre-post changes as well as to compare pre- and post-exercise lactate and ammonia levels. Countermovement jump height loss pre-post session (8%) was significant, and fatigue, measured as CMJ height loss, was strongly correlated to lactate (r = 0.97; p < 0.001) and ammonia (r = 0.92; p < 0.001) for all players. The relationships between the variables studied were determined by calculating the Pearson correlation coefficients. The metabolic stress developed during the effort can be estimated by controlling CMJ because of the high correlation between CMJ and blood lactate and ammonia concentrations. The high correlations found between mechanical (speed and CMJ height losses) and metabolic (lactate and ammonia) measures of fatigue highlight the utility and validity of using CMJ to monitor training load and quantify objectively neuromuscular fatigue during RSA.
Full Text Available PURPOSE: The study investigated the effects of FIFA 11+ and HarmoKnee, both being popular warm-up programs, on proprioception, and on the static and dynamic balance of professional male soccer players. METHODS: Under 21 year-old soccer players (n = 36 were divided randomly into 11+, HarmoKnee and control groups. The programs were performed for 2 months (24 sessions. Proprioception was measured bilaterally at 30°, 45° and 60° knee flexion using the Biodex Isokinetic Dynamometer. Static and dynamic balances were evaluated using the stork stand test and Star Excursion Balance Test (SEBT, respectively. RESULTS: The proprioception error of dominant leg significantly decreased from pre- to post-test by 2.8% and 1.7% in the 11+ group at 45° and 60° knee flexion, compared to 3% and 2.1% in the HarmoKnee group. The largest joint positioning error was in the non-dominant leg at 30° knee flexion (mean error value = 5.047, (p<0.05. The static balance with the eyes opened increased in the 11+ by 10.9% and in the HarmoKnee by 6.1% (p<0.05. The static balance with eyes closed significantly increased in the 11+ by 12.4% and in the HarmoKnee by 17.6%. The results indicated that static balance was significantly higher in eyes opened compared to eyes closed (p = 0.000. Significant improvements in SEBT in the 11+ (12.4% and HarmoKnee (17.6% groups were also found. CONCLUSION: Both the 11+ and HarmoKnee programs were proven to be useful warm-up protocols in improving proprioception at 45° and 60° knee flexion as well as static and dynamic balance in professional male soccer players. Data from this research may be helpful in encouraging coaches or trainers to implement the two warm-up programs in their soccer teams.
Wood, Susan; Harrison, Lesley K; Kucharska, Jo
Male professional footballers (soccer) represent an at-risk population of developing mental health difficulties and not accessing professional support. One in four current footballers report mental health difficulties. Higher prevalence is reported after retirement. This qualitative study aimed to provide in-depth insight into male professional footballers' lived experiences of mental health difficulties and help-seeking. Seven participants were interviewed. Data were analysed using interpretative phenomenological analysis. One superordinate theme emerged; 'Survival'. This related to survival in the professional football world, of mental health difficulties and after transition into the 'real world'. Six subordinate themes are explored alongside literature pertaining to male mental health, identity, injury, transition, and emotional development. Shame, stigma, fear and level of mental health literacy (knowledge of mental health and support) were barriers to help-seeking. Support for professional footballers' mental wellbeing requires improvement. Recommendations are made for future research, mental health education and support.
Bougault, Valérie; Drouard, François; Legall, Franck; Dupont, Grégory; Wallaert, Benoit
A high prevalence of respiratory allergies and exercise-induced bronchoconstriction (EIB) has been reported among endurance athletes. This study was designed to analyze the frequency of sensitization to respiratory allergens and EIB in young soccer players. Prospective cohort design. Youth academy and reserve professional soccer team during the seasons 2012 to 2013 and 2013 to 2014. Eighty-five soccer players (mean age: 20 ± 4 years) participated. Players underwent skin prick tests (SPTs) during the seasons 2012 to 2013 and 2013 to 2014. Spirometry and a eucapnic voluntary hyperpnea test were performed on soccer players during the first season 2012 to 2013 (n = 51) to detect EIB. Two self-administered questionnaires on respiratory history and allergic symptoms (European Community Respiratory Health Survey and Allergy Questionnaire for Athletes) were also distributed during both seasons (n = 59). The number of positive SPTs, exercise-induced respiratory symptoms, presence of asthma, airway obstruction, and EIB. Forty-nine percent of players were sensitized to at least one respiratory allergen, 33% reported an allergic disease, 1 player presented airway obstruction at rest, and 16% presented EIB. Factors predictive of EIB were self-reported exercise-induced symptoms and sensitization to at least 5 allergens. Questioning players about exercise-induced respiratory symptoms and allergies as well as spirometry at the time of the inclusion medical checkup would improve management of respiratory health of soccer players and would constitute inexpensive preliminary screening to select players requiring indirect bronchial provocation test or SPTs. This study showed that despite low frequencies, EIB and allergies are underdiagnosed and undertreated in young soccer players.
Academic and practitioner interest in the physical performance of male professional soccer players in the competition setting determined via time-motion analyses has grown substantially over the last four decades leading to a substantial body of published research and aiding development of a more systematic evidence-based framework for physical conditioning. Findings have forcibly shaped contemporary opinions in the sport with researchers and practitioners frequently emphasising the important role that physical performance plays in match outcomes. Time-motion analyses have also influenced practice as player conditioning programmes can be tailored according to the different physical demands identified across individual playing positions. Yet despite a more systematic approach to physical conditioning, data indicate that even at the very highest standards of competition, the contemporary player is still susceptible to transient and end-game fatigue. Over the course of this article, the author suggests that a more pragmatic approach to interpreting the current body of time-motion analysis data and its application in the practical setting is nevertheless required. Examples of this are addressed using findings in the literature to examine (a) the association between competitive physical performance and 'success' in professional soccer, (b) current approaches to interpreting differences in time-motion analysis data across playing positions, and (c) whether data can realistically be used to demonstrate the occurrence of fatigue in match-play. Gaps in the current literature and directions for future research are also identified.
Brito, João; Vasconcellos, Fabrício; Oliveira, José
This study aimed to analyse the short-term performance effects of three in-season low-volume strength-training programmes in college male soccer players. Fifty-seven male college soccer players (age: 20.31.6 years) were randomly assigned to a resistance-training group (n=12), plyometric training...... with the control group (pperformance by 4.6–6.2% (p....001) compared with the control group. No differences were observed in 5-m sprint and agility performances (p>0.05). Overall, the results suggest that in-season low-volume strength training is adequate for developing strength and speed in soccer players....
Full Text Available Whether a coach dismissal during the mid-season has an impact on the subsequent team performance has long been a subject of controversial scientific discussion. Here we find a clear-cut answer to this question by using a recently developed statistical framework for the team fitness and by analyzing the first two moments of the effect of a coach dismissal. We can show with an unprecedented small statistical error for the German soccer league that dismissing the coach within the season has basically no effect on the subsequent performance of a team. Changing the coach between two seasons has no effect either. Furthermore, an upper bound for the actual influence of the coach on the team fitness can be estimated. Beyond the immediate relevance of this result, this study may lead the way to analogous studies for exploring the effect of managerial changes, e.g., in economic terms.
A field test battery testing the selected physical attributes was administered. Aerobic performance, anaerobic endurance, agility, power, and 20 m and 40 m speed attributes demonstrated a significant difference (p < 0.05) between professional and amateur players. Semi-professionals also exhibited a significant difference (p ...
Henry, Thomas; Evans, Karrin; Snodgrass, Suzanne J; Miller, Andrew; Callister, Robin
To determine whether nonmodifiable and modifiable risk factors [ankle dorsiflexion range of motion (ROM), lower limb power output, and balance], as identified in preseason screening, predict the risk of sustaining a noncontact ankle injury in amateur male soccer players during the training and competitive season. Prospective cohort study. Amateur soccer competition (club and area representative teams). Amateur soccer players (n = 210) aged ≥15 years. Height, weight, ankle dorsiflexion ROM, power (vertical jump) and balance (time of double-leg balanced stance on an electronic wobble board, maximum 20 seconds) measured in preseason screening. Incidence of noncontact ankle injury and exposure to both training and games, monitored during the competitive season following baseline measurement. Noncontact ankle injury was defined as any ankle injury not caused by a collision (with another player or object) resulting in a participant missing at least 1 game or training session. Fourteen of the 210 participants (6.7%) sustained a noncontact ankle injury yielding an injury rate of 0.484 injuries per 1000 player hours. Lower limb power output scores amateur soccer players. These deficits can potentially be identified by screening, providing opportunities to investigate prevention strategies.
Makhlouf, Issam; Castagna, Carlo; Manzi, Vincenzo; Laurencelle, Louis; Behm, David G; Chaouachi, Anis
This study examined the effects of strength and endurance training sequence (strength before or after endurance) on relevant fitness variables in youth soccer players. Fifty-seven young elite-level male field soccer players (13.7 ± 0.5 years; 164 ± 8.3 cm; 53.5 ± 8.6 kg; body fat; 15.6 ± 3.9%) were randomly assigned to a control (n = 14, CG) and 3 experimental training groups (twice a week for 12 weeks) strength before (SE, n = 15), after (ES, n = 14) or on alternate days (ASE, n = 14) with endurance training. A significant (p = 0.001) intervention main effect was detected. There were only trivial training sequence differences (ES vs. SE) for all variables (p > 0.05). The CG showed large squat 1 repetition maximum (1RM) and medium sprint, change of direction ability, and jump improvements. ASE demonstrated a trivial difference in endurance performance with ES and SE (p > 0.05). Large to medium greater improvements for SE and ES were reported compared with ASE for sprinting over 10 and 30 m (p training sequence on soccer fitness-relevant variables. However, combining strength and endurance within a single training session provided superior results vs. training on alternate days. Concurrent training may be considered as an effective and safe training method for the development of the prospective soccer player.
Fujitaka, Kohei; Taniguchi, Akira; Kumai, Tsukasa; Otuki, Shingo; Okubo, Mamoru; Tanaka, Yasuhito
Studies comparing the types and severity of trauma and injuries caused by different types of field surfaces have been conducted. However, there have been no studies on sports injuries caused by temporal deterioration of long-pile artificial turf fields and related decreases in the rubber chip and silica sand infill. To investigate the influence of an artificial turf field on sports injuries in a university soccer team. Descriptive epidemiological study. A total of 397 male soccer players who were members of a single university soccer team were surveyed over a 12-year period, from April 2003 to March 2015. During this period, the team played for 4 years on a soil field (2003-2006) and 8 years on artificial turf (2007-2014). We analyzed the effect of changes in the artificial turf on the incidence rate of sports injuries (injury rate per 1000 athlete-exposures). We calculated the incidence rate of injuries sustained by the team and compared the results for each year of the study. After conversion of the field to artificial turf, there was a significant increase in the incidence of upper extremity trauma (P artificial turf (P artificial turf, there was a significant increase in the incidence of upper extremity trauma. After the refurbishing with additional rubber chips, the incidence of lower extremity muscle strain significantly declined. When analyzing measures that could prevent sports injuries related to soccer, it is necessary to take into consideration the changes that occur to the artificial turf over time.
Alentorn-Geli, Eduard; Alvarez-Diaz, Pedro; Ramon, Silvia; Marin, Miguel; Steinbacher, Gilbert; Boffa, Juan José; Cuscó, Xavier; Ballester, Jordi; Cugat, Ramon
To investigate the role of mechanical and contractile properties of skeletal muscles of the thigh, assessed through tensiomyography (TMG), as risk factors for anterior cruciate ligament (ACL) injury in male soccer players. Male soccer players with confirmed ACL tear included in this study underwent resting TMG assessment of thigh muscles of the uninjured side. The same values were obtained from a sex-, sports level-matched control group in both sides. The maximal displacement (Dm), delay time (Td), contraction time (Tc), sustained time (Ts), and half-relaxation time (Tr) were obtained for the following muscles in all subjects: vastus medialis (VM), vastus laterals (VL), rectus femoris (RF), semitendinosus (ST), and biceps femoris (BF). TMG values of the uninjured side in ACL-injured group were compared to mean values between both sides in the control subjects. There were 40 ACL-injured and 38 control individuals. The vast majority of TMG parameters were higher in the uninjured side of ACL-injured individuals compared to the control group. The VL-Tr, RF-Tc, RF-Ts, RF-Tr, and BF-Dm values were significantly higher in the uninjured side compared to the control group. Quadriceps muscles demonstrated more significant between-group differences than hamstring muscles. Specifically, RF was the muscle where most significant between-group differences were found. Resistance to fatigue and muscle stiffness in the hamstring muscles may be risk factors for ACL injury in male soccer players. In addition, a predominant impairment in TMG characteristics of the quadriceps over hamstrings may indicate an altered muscular co-contraction (imbalance) between both muscle groups, which might be another risk factor for ACL injury in this population. These findings should be taken into account when screening athletes at high risk of ACL injury and also to design adequate prevention programs for ACL injury in male soccer players.
Volpi, Piero; Taioli, Emanuela
Injuries are a major adverse event during a soccer player's career; they require medical and surgical treatment and rehabilitation and thus may interrupt the player's activity, often with severe physical and psychological sequel. Specialists have tried to identify the risk factors for injuries, in an attempt to discover predictors that could be prevented and or eliminated before the injury occurs, but the results are scarce. This article reviews the epidemiology of the frequency and occurrence of injuries in Italian soccer players, reports a list of preventable risk factors that are associated with injuries, and identifies preventable risk factors. We have identified personal factors (age, previous traumatic events, physical and biological characteristics of the player, life style habits such as smoking, alcohol, and diet, changes in physical-athletic aspects of the players, such as increased muscle strength, and use of medications) as possible risk factors for injuries. However, environmental factors such as changes in training techniques, field composition, and shoes structure may also have a major influence. This summary indicates that appropriate preventive measures can be undertaken to prevent injuries in professional soccer players. Professionals who are in close contacts with the players should be informed of the predictors of injuries and should be trained to intervene and plan appropriate preventive measures.
João Paulo Lara de Siqueira
Full Text Available Whereas an initial step in the management of stakeholders is the identification and classification of these actors, this study sought to answer the research question: how managers of Brazilian professional soccer clubs identify and classify their stakeholders? The theoretical framework used was the Stakeholder Theory, developed by Freeman (1984 and other researchers. The method used was proposed by Almeida et al. (2000, which assesses the saliency through the concepts power, legitimacy and urgency, that were proposed in the study of Mitchell et al. (1997. There were two propositions concerning the context of Brazilian soccer clubs: first, that the urgency perceived by managers in the demands of a stakeholder is high when his legitimacy is high and other one is that the most salient stakeholders for the managers are those with high degrees of legitimacy. Stakeholders were surveyed as perceived by the managers of Sociedade Esportiva Palmeiras. Three types of stakeholders were classified as demanding (sponsors, partners and the partner for the construction of the new stadium and three as dependents (members, athletes of professional soccer team and the media. Other stakeholders identified were classified as irrelevant, including the fans and and the organized groups of fans. It can be said that in the specific case of these managers of this particular football club, the trend was the acceptance of both propositions.
Jones, Rhys M; Cook, Christian C; Kilduff, Liam P; Milanović, Zoran; James, Nic; Sporiš, Goran; Fiorentini, Bruno; Fiorentini, Fredi; Turner, Anthony; Vučković, Goran
The aim of the present study was to investigate the relationship between maximal aerobic capacity (VO(2max)) and repeated sprint ability (RSA) in a group of professional soccer players. Forty-one professional soccer players (age 23 ± 4 yrs, height 180.0 ± 5.3 cm, weight 79.6 ± 5.3 kg) were required to perform tests to assess RSA and VO(2max) on two separate days with at least 48 hr rest between testing sessions. Each player performed a treadmill test to determine their VO(2max) and a test for RSA involving the players completing 6 × 40 m sprints (turn after 20 m) with 20 s active recovery between each sprint. There was a significant negative correlation between body mass normalised VO(2max) and mean sprint time (RSAmean) (r = -0.655; P soccer players in the recovery from repeated sprint type activities.
Full Text Available Reports based on experiences from masseurs and players, mostly without any scientific background, suggest that the combination of a classical regeneration method (i.e. massage with exposure to hypoxia may enhance regeneration in soccer. The aim of this study was to evaluate whether this specific combination could affect blood parameters related to muscle damage and physical strain after a soccer game. Approximately 15 hours after two separate championship games, 10 professional male outfield players of the first Austrian division were exposed to normobaric hypoxia (FiO2 13.5% ~ 4000m or normoxia for 1 hour (30 minutes rest followed by 30 min massage (cross-over design. Creatine kinase (CK, urea and uric acid (UA were measured 4 days before the first game, and 15 and 63 hours after the two games. Match play increased CK values independently of the intervention. No effect of the massage in combination with hypoxia was seen. A trend was found between ∆ UA ([UA] 48 hours after exposure minus [UA] before exposure in response to hypoxia and SaO2 measured in hypoxia (r=0.612, p=0.06. Results show that massage under hypoxic conditions had no additional positive effect on the measured parameters compared to massage alone. Solely the trend of a relationship for ∆ UA and SaO2 might indicate that redox alterations are a potential consequence of hypoxic exposure.
Owen, Adam L; Wong, Del P; Paul, Darren; Dellal, Alexandre
The present study examined the effects of periodized small-sided game (SSG) training intervention during a 4-week in-season break on the physical performance changes (i.e., speed, aerobic performance, and repeated sprint ability) within elite European soccer players. Fifteen, elite, male, professional players (age: 24.5 ± 3.45 years; height: 181.1 ± 5.78 cm; body mass: 78.7 ± 7.67 kg; VO2max: 54.88 ± 5.25 ml·kg(-1)·min(-1)) from a Scottish Premier League team participated in 7 separate SSG sessions (3 vs. 3 plus goalkeepers) of which games lasted for a 3-minute duration for the selected number of games (ranged from 5 to 11) increasing over the intervention period. To examine the effects of the SSG intervention on physical performance changes, pre- and posttesting sessions took place over a 2-day period (day 1: anthropometry and repeated sprint ability [RSA] assessments; day 2: running economy [RE] and blood lactate assessments). Results show that the 4-week SSG training intervention induced significant improvement in RSA as indicated by faster 10-m sprint time (p soccer players' physical fitness characteristics. Being able to develop physical characteristics in conjunction to technical and tactical elements of the game, within a relatively short period, makes SSGs an appealing proposition for fitness coaches, players, and technical coaches alike.
Kavaliauskas, Mykolas; Kilvington, Ross; Babraj, John
Soccer performance is determined by a number of physiological adaptations that can be altered by high intensity training. However, the effectiveness of using an uphill sprint based protocol has not been demonstrated for soccer players. We sought to determine the effectiveness of an in-season uphill sprint training (UST) programme on soccer related physiological outcomes. Fourteen male soccer players (age: 22±8 years, height: 1.81±8 m, body mass: 76±12 kg) underwent testing (5-10-5 agility drill, Yo-Yo Intermittent Recovery Test Level 1, leg and back dynamometry and 3 km time trial) at baseline and after 6 weeks of UST or normal activity. Participants were allocated to a control (N.=7) or UST (N.=7) group. The UST group took part in twice weekly training consisting of 10 x 10 sec sprints with 60s recovery on a 7% gradient for six weeks. The control group maintained normal activity patterns. 3 km time trial, strength, agility and Yo-Yo performance were all significantly improved pre to post following 6 weeks of UST (agility 3%, d=1.3; strength 10%, d=-3.2; VO2max 3%, d=-1.4; 3-km TT 4%, d=1.3). In the control group 3 km time trial, strength, agility and Yo-Yo performance remained unchanged after 6 weeks (agility 0.1%, d=-0.2; strength 2%, d=0.0; VO2max -0.1%, d=0.0; 3-km TT 1.3%, d=0.3). Therefore in-season short duration UST is an effective way to improve soccer fitness in a time efficient manner.
Full Text Available Patrizia Proia,1 Antonino Bianco,1 Gabriella Schiera,2 Patrizia Saladino,2 Valentina Contrò,1 Giovanni Caramazza,3 Marcello Traina,1 Keith A Grimaldi,4 Antonio Palma,1 Antonio Paoli5 1Sport and Exercise Sciences Research Unit, 2Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, University of Palermo, Palermo, Italy; 3Regional Sports School of CONI Sicilia, Sicily, Italy; 4Biomedical Engineering Laboratory, Institute of Communication and Computer Systems, National Technical University of Athens, Athens, Greece; 5Department of Biomedical Sciences, University of Padova, Padua, Italy Background: The PPARα gene encodes the peroxisome proliferator-activator receptor alpha, a central regulator of expression of other genes involved in fatty acid metabolism. The purpose of this study was to determine the prevalence of G allele of the PPARα intron 7 G/C polymorphism (rs4253778 in professional Italian soccer players. Methods: Sixty professional soccer players and 30 sedentary volunteers were enrolled in the study. Samples of venous blood were obtained at rest, in the morning, by conventional clinical procedures; blood serum was collected and total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglycerides were measured. An aliquot of anticoagulant-treated blood was used to prepare genomic DNA from whole blood. The G/C polymorphic site in PPARα intron 7 was scanned by using the PCR-RFLP (polymerase chain reaction restriction fragment length polymorphism protocol with TaqI enzyme. Results: We found variations in genotype distribution of PPARα polymorphism between professional soccer players and sedentary volunteers. Particularly, G alleles and the GG genotype were significantly more frequent in soccer players compared with healthy controls (64% versus 48%. No significant correlations were found between lipid profile and genotype background. Conclusion: Previous results
van der Horst, Nick; Priesterbach, Annique; Backx, Frank; Smits, Dirk-Wouter
This study investigated the hamstring-and-lower-back flexibility (HLBF) of male adult amateur soccer players, using the sit-and-reach test (SRT), with a view to obtaining population-based reference values and to determining whether SRT scores are associated with player characteristics. Cross-sectional cohort study. Teams from high-level Dutch amateur soccer competitions were recruited for participation. Dutch male high-level amateur field soccer players (n = 449) of age 18 to 40 years. Players with a hamstring injury at the moment of SRT-measurement or any other injury that prevented them from following the SRT protocol were excluded. Sit-and-reach test scores were measured and then population-based reference values were calculated as follows: >2SD below mean (defining "very low" HLBF), 1SD-2SD below mean ("low" HLBF), 1SD below mean to 1SD above mean ("normal" HLBF), 1SD-2SD above mean ("high" HLBF), and >2SD above mean ("very high" HLBF). Whether SRT scores were correlated with player characteristics was determined using a Pearson correlation coefficient or Spearman rho. Sit-and-reach test scores ranged from 0 to 43.5 cm (mean 22.0 cm, SD 9.2). The cutoff points for population-based reference values were 40.5 cm for "very high". Sit-and-reach test scores were significantly associated with players' height (ρ = -0.132, P = 0.005), body mass index (r = 0.114, P = 0.016), and history of anterior cruciate ligament surgery (P amateur soccer players. The SRT reference values with cutoff points may facilitate evidence-based decision making regarding HLBF, and the SRT might be a useful tool to assess injury risk, performance, or for diagnostic purposes.
Nassis, George P; Geladas, Nickos D; Soldatos, Yiannis; Sotiropoulos, Aristomenis; Bekris, Vaggelis; Souglis, Athanasios
The aim of this study was to examine the relationship of 2 different field tests for the assessment of aerobic fitness in soccer players with the multistage 20-m test used for the evaluation of maximum oxygen uptake. Nineteen semi-professional male soccer players (age: 22.8 ± 2.5 mean ± SD) performed, under similar conditions, 3 field tests in a counterbalanced order 7 days apart. These tests were the multistage 20-m shuttle run test (MSRT), the Bangsbo test, and the Hoff test. Heart rate was recorded in all tests with telemetry, and the Borg scale was introduced at the end of exercise. Finally, 3-minute post-test lactate concentration was determined. Performance was 11.2 ± 0.9 levels in the MSRT, 1,658.9 ± 119.9 m in the Bangsbo test, and 1,798.2 ± 125.9 m in the Hoff test. There was a significant correlation between the Hoff test and performance in the MSRT (r = 0.49, p 0.05). The maximum heart rate achieved in the Bangsbo test was significantly lower compared with that in the MSRT and Hoff test (Bangsbo: 186.6 ± 9.6, Hoff: 192 ± 7.6, MSRT: 190.4 ± 9.3 beats/min, p < 0.05). No difference was found in post-test lactate concentration among the 3 tests. In conclusion, the Hoff test can be used for the assessment of endurance in adult semi-professional soccer players. Coaches and teams could benefit from using the Hoff test that resembles soccer actions for the assessment of players' aerobic fitness.
Malone, James J; Jaspers, Arne; Helsen, Werner F; Merks, Brenda; Frencken, Wouter Gp; Brink, Michel S
The purpose of this investigation was to: (a) quantify the training load practices of a professional soccer GK, and (b) investigate the relationship between the training load observed and the subsequent self-reported wellness response. One male goalkeeper playing for a team in the top league of the Netherlands participated in this case study. Training load data were collected across a full season using a global positioning system (GPS) device and session rating of perceived exertion (session-RPE). Data was assessed in relation to the number of days to a match (MD- and MD+). In addition, self-reported wellness was assessed using a questionnaire. Duration, total distance, average speed, PlayerLoad TM and load (derived from session-RPE) were highest on MD. The lowest values for duration, total distance and PlayerLoad TM were observed on MD-1 and MD+1. Total wellness scores were highest on MD and MD-3 and were lowest on MD+1 and MD-4. Small to moderate correlations between training load measures (duration, total distance covered, high deceleration efforts and load) and the self-reported wellness scores were found. This exploratory case-study provides novel data about the physical load undertaken by a goalkeeper during one competitive season. The data suggest there are small to moderate relationships between training load indicators and self-reported wellness. This weak relation indicates that the association is not meaningful. This may be due to the lack of position-specific training load parameters we can currently measure in the applied context.
Yang, Cheng-I; Gau, Meei-Ling; Shiau, Shu-Jen; Hu, Wei-Herng; Shih, Fu-Jin
The aim of this paper is to report a study to: (a) explore Taiwanese male nurses' motivations for becoming a nurse; (b) reveal their professional developmental process in nursing; (c) understand the difficulties hindering their professional development from both professional and gender aspects; and (d) identify the strategies they use to cope with these difficulties. Hindered by historical, cultural, economic and warfare factors, the proportion of male nurses in Taiwan remains low. Taiwanese male nurses' career development process has not been well investigated yet. A descriptive qualitative research design was used, with a convenience sample of 15 male nurses (mean age 30.8 years) with a Bachelor's degree in Nursing Science. Data were collected by semi-structured interviews and analysed by content analysis. Taiwanese male nurses' entrance into the nursing profession involved three phases: pre-study, study and employment. The difficulties encountered during career development were related to the gender expectations of patients and the general public. The nurses received support more from superiors than from colleagues. The strategies they used included (a) improving their professional knowledge and skills to obtain higher levels of satisfaction and better opportunities for promotion; (b) thinking aggressively about job promotion; (c) choosing specialist departments as appropriate environments for graduate study and personal growth; and (d) changing their professional track for personal growth. Based on the nature of nursing work and clinical experiences, Taiwanese male nurses believed that nursing was a profession suitable for both men and women. Their preparation for career development started at the pre-study phase. The major strategies they used were related to a strong desire for personal growth and professional promotion. Finally, a conceptual framework was developed to depict this complex phenomenon.
Boisseau, N; Le Creff, C; Loyens, M; Poortmans, J R
Recommendations for the requirements for protein intake amount usually to 0.8-1.0 g x kg(-1) body mass x day(-1) in adolescents without any reference to the undertaking of acute exercise or to the training status. The present investigation intended to determine the nitrogen balance and protein intake in 8 healthy male non-active adolescents and 11 adolescent soccer players, both groups aged about 15 years. An assessment of nutrient intake was obtained by analysing 7 day food records collected by a questionnaire. Nitrogen excretion rate was determined and nitrogen balance was calculated from the mean daily protein intake and the urinary excretion. The results showed that the nutritional status of the two groups was similar. Nevertheless, we found that their diets were quite inappropriate in terms of the intakes of carbohydrate, some minerals (zinc, calcium, magnesium), vitamins (A, B6, D) and fibre. A positive nitrogen balance was observed from a mean protein intake of 1.57 g x kg(-1) body mass x day(-1) in these adolescents, whether they were non-active or athletes. Thus, the present investigation indicated that the growth and development in non-active adolescents and in adolescent soccer-players give rise to a need for a higher protein intake than is usually recommended. However, the higher protein requirements did not seem to be related only to the increased energy expenditure imposed by the exercise training in the soccer-player group.
Deol, Rupinderbir Singh; Roche, Andrew; Calder, James D F
Lisfranc joint injuries are increasingly recognized in elite soccer and rugby players. Currently, no evidence-based guidelines exist on time frames for return to training and competition after surgical treatment. To assess the time to return to training and playing after Lisfranc joint injuries. Case series; Level of evidence, 4. A consecutive series of 17 professional soccer and rugby players in the English Premier/Championship leagues was assessed using prospectively collected data. All were isolated injuries sustained during training or competitive matches. Each player had clinical and radiological evidence of an unstable Lisfranc injury and required surgical treatment. A standardized postoperative regimen was used. The minimum follow-up time was 2 years. Clinical and radiological follow-up was obtained in all 17 players. Seven players had primarily ligamentous injuries, and 10 had bony injuries. The time from injury to fixation ranged from 8 to 31 days, and hardware was removed at 16 weeks postoperatively. One athlete retired after a ligamentous injury; the remaining 16 players returned to training and full competition. Excluding the retired player, the mean time to return to training was 20.1 weeks (range, 18-24 weeks) and to full competition was 25.3 weeks (range, 21-31 weeks). There was a significant difference between the mean time to return to competition for rugby (27.8 weeks) and soccer players (24.1 weeks; P = .02) and for ligamentous (22.5 weeks) compared with bony injuries (26.9 weeks; P = .003). Three patients suffered deep peroneal nerve sensation loss, from which 1 patient did not fully recover. Return to competitive elite-level soccer and rugby is possible after surgically treated Lisfranc injuries. Return to training can take up to 24 weeks and return to playing up to 31 weeks, with bony injuries taking longer. © 2015 The Author(s).
Full Text Available Kicking and cutting skills in soccer are clearly unilateral, require asymmetrical motor patterns and lead to the development of asymmetrical adaptations in the musculoskeletal function of the lower limbs. Assuming that these adaptations constitute a chronicity-dependent process, this study examined the effects of professional training age (PTA on the composite strength profile of the knee and ankle joint in soccer players. One hundred soccer players (n=100 with short (5-7 years, intermediate (8-10 years and long (>11 years PTA were tested bilaterally for isokinetic concentric and eccentric strength of the knee and ankle muscles. Knee flexion-extension was tested concentrically at 60°, 180° and 300 °/sec and eccentrically at 60° and 180 °/sec. Ankle dorsal and plantar flexions were tested at 60 °/sec for both the concentric and eccentric mode of action. Bilaterally averaged muscle strength [(R+L/2] increased significantly from short training age to intermediate and stabilized afterwards. These strength adaptations were mainly observed at the concentric function of knee extensors at 60°/sec (p = 0. 023, knee flexors at 60°/sec (p = 0.042 and 180°/sec (p = 0.036, and ankle plantar flexors at 60o/sec (p = 0.044. A linear trend of increase in isokinetic strength with PTA level was observed for the eccentric strength of knee flexors at 60°/sec (p = 0.02 and 180°/sec (p = 0.03. Directional (R/L asymmetries decreased with PTA, with this being mainly expressed in the concentric function of knee flexors at 180°/sec (p = 0.04 and at 300 °/sec (p = 0.03. These findings confirm the hypothesis of asymmetry in the strength adaptations that take place at the knee and ankle joint of soccer players mainly along with short and intermediate PTA. Players with a longer PTA seem to adopt a more balanced use of their lower extremities to cope with previously developed musculoskeletal asymmetries and possibly reduce injury risk. This has certain
Powers, Christopher M; Ghoddosi, Navid; Straub, Rachel K; Khayambashi, Khalil
Diminished hip-abductor strength has been suggested to increase the risk of noncontact lateral ankle sprains. To determine prospectively whether baseline hip-abductor strength predicts future noncontact lateral ankle sprains in competitive male soccer players. Prospective cohort study. Athletic training facilities and various athletic fields. Two hundred ten competitive male soccer players. Before the start of the sport season, isometric hip-abductor strength was measured bilaterally using a handheld dynamometer. Any previous history of ankle sprains, body mass index, age, height, and weight was documented. During the sport season (30 weeks), ankle injury status was recorded by team medical providers. Injured athletes were further classified based on the mechanism of injury. Only data from injured athletes who sustained noncontact lateral ankle sprains were used for analysis. Postseason, logistic regression was used to determine whether baseline hip strength predicted future noncontact lateral ankle sprains. A receiver operating characteristic curve was constructed for hip strength to determine the cutoff value for distinguishing between high-risk and low-risk outcomes. A total of 25 noncontact lateral ankle sprains were confirmed, for an overall annual incidence of 11.9%. Baseline hip-abductor strength was lower in injured players than in uninjured players (P = .008). Logistic regression indicated that impaired hip-abductor strength increased the future injury risk (odds ratio = 1.10 [95% confidence interval = 1.02, 1.18], P = .010). The strength cutoff to define high risk was ≤33.8% body weight, as determined by receiver operating characteristic curve analysis. For athletes classified as high risk, the probability of injury increased from 11.9% to 26.7%. Reduced isometric hip-abductor strength predisposed competitive male soccer players to noncontact lateral ankle sprains.
Pau, Massimiliano; Arippa, Federico; Leban, Bruno; Corona, Federica; Ibba, Gianfranco; Todde, Francesco; Scorcu, Marco
To assess the existence of correlations between static and dynamic balance abilities in young and professional elite soccer players. Cross-sectional. Fifty-one elite players who regularly compete at national level divided into two groups: Professional (age 18-34, n = 20) and Under 15-17 (age 14-16, n = 31). Dynamic balance was assessed for the case of a single-leg landing task by means of vertical time to stabilization (TTS) and postural sway calculated on the basis of center-of-pressure (COP) trajectories (sway area, COP displacements in antero-posterior and medio-lateral direction, COP path length). The same parameters were also measured for a 20 s one-legged stance to assess static balance abilities. No significant correlations were found between static and dynamic balance parameters except for TTS and COP displacements in the antero-posterior direction (r = 0.29, p = 0.003). Professional players are characterized by lower TTS in comparison with youth leagues players (0.767 vs. 1.188 s for the dominant limb, p balance in soccer players should be performed with both dynamic and static tests, considering that the postural control performances in the two cases are not related. Copyright © 2014 Elsevier Ltd. All rights reserved.
van Beijsterveldt, Anna M C; van de Port, Ingrid G L; Krist, Mark R; Schmikli, Sandor L; Stubbe, Janine H; Frederiks, Janet E; Backx, Frank J G
Background The incidence rate of soccer injuries is among the highest in sports, particularly for adult male soccer players. Purpose To investigate the effect of the ‘The11’ injury prevention programme on injury incidence and injury severity in adult male amateur soccer players. Study design Cluster-randomised controlled trial. Methods Teams from two high-level amateur soccer competitions were randomly assigned to an intervention (n=11 teams, 223 players) or control group (n=12 teams, 233 players). The intervention group was instructed to perform The11 in each practice session during one soccer season. The11 focuses on core stability, eccentric training of thigh muscles, proprioceptive training, dynamic stabilisation and plyometrics with straight leg alignment. All participants of the control group continued their practice sessions as usual. Results In total, 427 injuries were recorded, affecting 274 of 456 players (60.1%). Compliance with the intervention programme was good (team compliance=73%, player compliance=71%). Contrary to the hypothesis, injury incidences were almost equal between the two study groups: 9.6 per 1000 sports hours (8.4–11.0) for the intervention group and 9.7 (8.5–11.1) for the control group. No significant differences were found in injury severity, but a significant difference was observed in the location of the injuries: players in the intervention group sustained significantly less knee injuries. Conclusions This study did not find significant differences in the overall injury incidence or injury severity between the intervention and control group of adult male soccer players. More research is recommended, focusing on injury aetiology and risk factors in adult male amateur soccer players. PMID:22878257
Steadman, Richard J.
Background: Little information is available on the results of microfracture in competitive football (soccer) players. We aimed to evaluate the efficacy of this technique to restore joint function to a level that allows return to this popular high-impact sport. Methods: This article provides an overview of the basic science and the current published scientific evidence for articular cartilage repair using the microfracture technique in elite football (soccer) athletes. In addition, the senior author documents his results in a case series of professional football (soccer) players treated with microfracture. Results: Twenty-one professional male soccer players underwent microfracture for knee articular cartilage defects. Nineteen players had isolated cartilage injuries, and 2 players had simultaneous anterior cruciate ligament injuries. Average age of the player was 27 years (range, 18-32 years). Twelve players (57%) had single defects, and 9 (43%) had multiple defects. All players complied with the postoperative rehabilitation program. Twenty players (95%) returned to professional soccer the season following microfracture surgery and continued to play for an average of 5 years (range, 1-13 years). Years of continued play inversely correlated with player age at the time of microfracture (r = -0.41). Conclusion: Articular cartilage repair with the microfracture technique followed by appropriate rehabilitation provides restoration of knee joint function in professional football (soccer) players with a high rate of return to football (soccer) and continued participation under the significant demands of professional football (soccer). Thorough understanding of the technical aspects, rehabilitation, and literature can help to optimize the results of microfracture in the athletic population. PMID:26069602
Silvers-Granelli, Holly; Mandelbaum, Bert; Adeniji, Ola; Insler, Stephanie; Bizzini, Mario; Pohlig, Ryan; Junge, Astrid; Snyder-Mackler, Lynn; Dvorak, Jiri
The Fédération Internationale de Football Association (FIFA) 11+ program has been shown to be an effective injury prevention program in the female soccer cohort, but there is a paucity of research to demonstrate its efficacy in the male population. To examine the efficacy of the FIFA 11+ program in men's collegiate United States National Collegiate Athletic Association (NCAA) Division I and Division II soccer. Randomized controlled trial; Level of evidence, 1. Before the commencement of the fall 2012 season, every NCAA Division I and Division II men's collegiate soccer team (N = 396) was solicited to participate in this research study. Human ethics review board approval was obtained through Quorum Review IRB. Sixty-five teams were randomized: 34 to the control group (CG; 850 players) and 31 to the intervention group (IG; 675 players). Four teams in the IG did not complete the study, reducing the number for analysis to 61. The FIFA 11+ injury prevention program served as the intervention and was utilized weekly. Athlete-exposures (AEs), compliance, and injury data were recorded using a secure Internet-based system. In the CG, 665 injuries (mean ± SD, 19.56 ± 11.01) were reported for 34 teams, which corresponded to an incidence rate (IR) of 15.04 injuries per 1000 AEs. In the IG, 285 injuries (mean ± SD, 10.56 ± 3.64) were reported for 27 teams, which corresponded to an IR of 8.09 injuries per 1000 AEs. Total days missed because of injury were significantly higher for the CG (mean ± SD, 13.20 ± 26.6 days) than for the IG (mean ± SD, 10.08 ± 14.68 days) (P = .007). There was no difference for time loss due to injury based on field type (P = .341). The FIFA 11+ significantly reduced injury rates by 46.1% and decreased time loss to injury by 28.6% in the competitive male collegiate soccer player (rate ratio, 0.54 [95% CI, 0.49-0.59]; P < .0001) (number needed to treat = 2.64). © 2015 The Author(s).
Full Text Available This cross-sectional study compared somatic, endurance performance determinants and heart rate variability (HRV profiles of professional soccer players divided into different age groups: GI (17–19.9 years; n = 23, GII (20–24.9 years; n = 45, GIII (25–29.9 years; n = 30, and GIV (30–39 years; n = 26. Players underwent somatic and HRV assessment and maximal exercise testing. HRV was analyzed by spectral analysis of HRV, and high (HF and low (LF frequency power was transformed by a natural logarithm (Ln. Players in GIV (83 ± 7 kg were heavier (p 25 years showed negligible differences in Pmax unlike the age group differences demonstrated in VO2max. A shift towards relative sympathetic dominance, particularly due to reduced vagal activity, was apparent after approximately 8 years of competing at the professional level.
Full Text Available Angiotensin-1 converting enzyme (ACE gene and α-actinin-3 (ACTN3 gene polymorphisms are considered to be the most important candidate genes for genetic predisposition to human athletic performance. In the present study, we aimed to analyze the distribution of ACE and ACTN3 polymorphisms for the first time in male Turkish soccer players. In this prospective study, our cohort consisted of 25 professional players, all with Turkish ancestry. Polymerase chain reaction (PCR-restriction length polymorphism was used for the characterization of the genotype of ACTN3 and single PCR for ACE . For ACE genotype, 16%, 44%, and 40% of the players had insertion/insertion (II, insertion/deletion (ID, and deletion/deletion (DD genotypes, respectively, whereas 20% had XX, 36% had RX, and 44% had RR genotypes for ACTN3 . When we examined the allelic percentages, for ACE , D allele was recorded as 62 and I as 38, and for ACTN3 , R allele was 62 and X was 38. Our results were in agreement with the previous reports, indicating the presence of ACTN3 D and ACE X allele in soccer players. We suggest that ACE and ACTN3 genotypes are important biomarkers for genetic counseling for the individuals who are prone to be successful soccer players.
Ghareeb, Dana M; McLaine, Alice J; Wojcik, Janet R; Boyd, Joni M
Ghareeb, DM, McLaine, AJ, Wojcik, JR, and Boyd, JM. Effects of two warm-up programs on balance and isokinetic strength in male high school soccer players. J Strength Cond Res 31(2): 372-379, 2017-One of the most common warm-up programs used to prevent injury in soccer, FIFA11+, integrates aerobic, strength, and balance. The purpose of this study was to compare FIFA11+ to a new warm-up program (NWP) on balance and isokinetic strength of the quadriceps and hamstrings at 60, 180, and 300°·s in male high school soccer players. Participants at one school (n = 17) performed the NWP before practice for 6 weeks during one soccer season, whereas participants at another school (n = 17) performed FIFA11+. There were no differences at baseline. At posttest, players in NWP significantly improved (p 1.3. No changes were seen in FIFA11+. Isokinetic strength peak torque increased at 60°·s in the quadriceps and hamstrings in dominant and nondominant legs in NWP (p soccer conditioning by improving balance and isokinetic strength.
Krist, M.R.; Beijsterveldt, A.M.C van; Backx, F.J.G.; Wit, G.A. de
QUESTION: Is an injury prevention program consisting of 10 exercises designed to improve stability, muscle strength, co-ordination, and flexibility of the trunk, hip and leg muscles (known as The11) cost effective in adult male amateur soccer players?DESIGN: Cost-effectiveness analysis of a
Valente-dos-Santos, Joao; Coelho-e-Silva, Manuel J.; Simoes, Filipe; Figueiredo, Antonio J.; Leite, Neiva; Elferink-Gemser, Marije T.; Malina, Robert M.; Sherar, Lauren
This study evaluates the contributions of age. growth, skeletal maturation, playing position and training to longitudinal changes in functional and skill performance in male youth soccer. Players were annually followed over 5 years (n = 83, 4.4 measurements per player). Composite scores for
Gil, Susana María; Zabala-Lili, Jon; Bidaurrazaga-Letona, Iraia; Aduna, Badiola; Lekue, Jose Antonio; Santos-Concejero, Jordan; Granados, Cristina
Abstract The aim of this study was to analyse the talent identification process of a professional soccer club. A preselection of players (n = 64) aged 9-10 years and a final selection (n = 21) were performed by the technical staff through the observation during training sessions and matches. Also, 34 age-matched players of an open soccer camp (CampP) acted as controls. All participants underwent anthropometric, maturity and performance measurements. Preselected outfield players (OFs) were older and leaner than CampP (P < 0.05). Besides, they performed better in velocity, agility, endurance and jump tests (P < 0.05). A discriminant analysis showed that velocity and agility were the most important parameters. Finally, selected OFs were older and displayed better agility and endurance compared to the nonselected OFs (P < 0.05). Goalkeepers (GKs) were taller and heavier and had more body fat than OFs; also, they performed worse in the physical tests (P < 0.05). Finally, selected GKs were older and taller, had a higher predicted height and advanced maturity and performed better in the handgrip (dynamometry) and jump tests (P < 0.05). Thus, the technical staff selected OFs with a particular anthropometry and best performance, particularly agility and endurance, while GKs had a different profile. Moreover, chronological age had an important role in the whole selection process.
Cunha, Giovani S; Cumming, Sean P; Valente-Dos-Santos, João; Duarte, João P; Silva, Gustavo; Dourado, Antonio C; Leites, Gabriela T; Gaya, Adroaldo C; Reischak-Oliveira, Álvaro; Coelho-E-Silva, Manuel
This study examined power output on jumping and sprinting tests in young soccer players of differing pubertal status, while controlling for body size with allometric scaling exponents. A total of 46 males aged 12-18 years (14.17 years) were divided into three groups: pre-pubescent ( n = 12), pubescent ( n = 22), and post-pubescent ( n = 12). Participants performed a series of tests, including the squat jump (SJ), countermovement jump (CMJ), and 10-meter and 30-meter sprint test protocols. The Post-PUB group was older ( F = 112.411, p soccer ( F = 8.055, p = 0.001), taller ( F = 28.940, p soccer players.
Rey, Ezequiel; Padrón-Cabo, Alexis; Fernández-Penedo, Diego
The purpose of this study was to assess the effect resisted sprint training using weighted vests (WVs) compared with unresisted sprint (US) training on physical fitness (countermovement jump, 10-m sprint, 30-m sprint, and repeated sprint ability [RSA]) in amateur male soccer players. Nineteen soccer players (age: 23.7 ± 4.5 years; height: 178.3 ± 5.8 cm; body mass: 72.9 ± 5.2 kg) were randomly assigned to a WV (n = 10) or a US (n = 9) group. The intervention program had to be performed 2 times a week over 6 weeks. The only difference between the 2 interventions was that the WV group performed all the sprints with an additional weight of 18.9% ± 2.1% of body mass. Within-group analysis showed significant improvements (p soccer-related performance measures, and could be beneficial to players and coaches in field settings.
Vincent Gouttebarge, Frank J.G. Backx, Haruhito Aoki, Gino M.M.J. Kerkhoffs
Full Text Available Evidence on the prevalence of symptoms related to distress, anxiety/depression or substance abuse/dependence, – typically referred to as symptoms of common mental disorders (CMD – is lacking in European professional football (soccer. The aims of the present study were to investigate the prevalence of symptoms related to CMD (distress, anxiety/depression, sleeping disturbance, adverse alcohol behaviour, and adverse nutrition behaviour in professional footballers from five European countries, and to explore associations of the outcome measures under study with life events and career dissatisfaction. A cross-sectional design was used. Questionnaires were distributed among professional footballers by the national players’ unions in Finland, France, Norway, Spain and Sweden. The highest prevalence of symptoms related to common mental disorders were 18% for distress (Sweden, 43% for anxiety/depression (Norway, 33% for sleeping disturbance (Spain, 17% for adverse alcohol behaviour (Finland, and 74% for adverse nutrition behaviour (Norway. In Finland, France and Sweden, both life events and career dissatisfaction were associated with distress, anxiety/depression, adverse alcohol behaviour, and adverse nutrition behaviour. Results suggest the need for self-awareness in professional football about common mental disorders and a multidisciplinary approach by the medical team.
Váczi, Márk; Tollár, József; Meszler, Balázs; Juhász, Ivett; Karsai, István
The aim of the present study was to investigate the effects of a short-term in-season plyometric training program on power, agility and knee extensor strength. Male soccer players from a third league team were assigned into an experimental and a control group. The experimental group, beside its regular soccer training sessions, performed a periodized plyometric training program for six weeks. The program included two training sessions per week, and maximal intensity unilateral and bilateral plyometric exercises (total of 40 - 100 foot contacts/session) were executed. Controls participated only in the same soccer training routine, and did not perform plyometrics. Depth vertical jump height, agility (Illinois Agility Test, T Agility Test) and maximal voluntary isometric torque in knee extensors using Multicont II dynamometer were evaluated before and after the experiment. In the experimental group small but significant improvements were found in both agility tests, while depth jump height and isometric torque increments were greater. The control group did not improve in any of the measures. Results of the study indicate that plyometric training consisting of high impact unilateral and bilateral exercises induced remarkable improvements in lower extremity power and maximal knee extensor strength, and smaller improvements in soccer-specific agility. Therefore, it is concluded that short-term plyometric training should be incorporated in the in-season preparation of lower level players to improve specific performance in soccer.
Váczi, Márk; Tollár, József; Meszler, Balázs; Juhász, Ivett; Karsai, István
The aim of the present study was to investigate the effects of a short-term in-season plyometric training program on power, agility and knee extensor strength. Male soccer players from a third league team were assigned into an experimental and a control group. The experimental group, beside its regular soccer training sessions, performed a periodized plyometric training program for six weeks. The program included two training sessions per week, and maximal intensity unilateral and bilateral plyometric exercises (total of 40 – 100 foot contacts/session) were executed. Controls participated only in the same soccer training routine, and did not perform plyometrics. Depth vertical jump height, agility (Illinois Agility Test, T Agility Test) and maximal voluntary isometric torque in knee extensors using Multicont II dynamometer were evaluated before and after the experiment. In the experimental group small but significant improvements were found in both agility tests, while depth jump height and isometric torque increments were greater. The control group did not improve in any of the measures. Results of the study indicate that plyometric training consisting of high impact unilateral and bilateral exercises induced remarkable improvements in lower extremity power and maximal knee extensor strength, and smaller improvements in soccer-specific agility. Therefore, it is concluded that short-term plyometric training should be incorporated in the in-season preparation of lower level players to improve specific performance in soccer. PMID:23717351
Full Text Available Abstract Exercise training is known to induce an increase in free radical production potentially leading to enhanced muscle injury. Vitamins C and E are well known antioxidants that may prevent muscle cell damage. The purpose of this study was to determine the effects of these supplemental antioxidant vitamins on markers of oxidative stress, muscle damage and performance of elite soccer players. Ten male young soccer players were divided into two groups. Supplementation group (n = 5 received vitamins C and E supplementation daily during the pre-competitive season (S group, while the placebo group (PL group, n = 5 received a pill containing maltodextrin. Both groups performed the same training load during the three-month pre-season training period. Erythrocyte antioxidant enzymes glutathione reductase, catalase and plasma carbonyl derivatives did not show any significant variation among the experimental groups. Similarly, fitness level markers did not differ among the experimental groups. However, S group demonstrated lower lipid peroxidation and muscle damage levels (p
Beijsterveldt, A.M.C. van; Krist, M.R.; Schmikli, S.L.; Stubbe, J.H.; Wit, G.A. de; Inklaar, H.; Port, I.G.L. van de; Backx, F.J.G.
Background and aims Approximately 16% of all sports injuries in the Netherlands are caused by outdoor soccer. A cluster-randomised controlled trial has been designed to investigate the effectiveness and cost-effectiveness of an injury prevention programme ('The11') for male amateur soccer players.
Isaiah T. McFarland
Full Text Available In collegiate level soccer acceleration, maximal velocity and agility are essential for successful performance. Power production is believed to provide a foundation for these speed qualities. The purpose of this study was to determine the relationship of change of direction speed, acceleration, and maximal velocity to both the counter movement jump (CMJ and squat jump (SJ in collegiate soccer players. Thirty-six NCAA Division II soccer players (20 males and 16 females were tested for speed over 10 and 30 m, CODS (T-test, pro agility and power (CMJ, SJ. Independent t-tests (p ≤ 0.05 were used to derive gender differences, and Pearson’s correlations (p ≤ 0.05 calculated relationships between the different power and speed tests. Female subjects displayed moderate-to-strong correlations between 30 m, pro agility and T-test with the CMJ (r = −0.502 to −0.751, and SJ (r = −0.502 to −0.681. Moderate correlations between 10 and 30 m with CMJ (r = −0.476 and −0.570 and SJ (r = −0.443 and −0.553, respectively were observed for males. Moderate to strong relationships exist between speed and power attributes in both male and female collegiate soccer players, especially between CMJ and maximal velocity. Improving stretch shortening cycle (SSC utilization may contribute to enhanced sport-specific speed.
Full Text Available Gunnar Mathisen, Svein Arne Pettersen School of Sport Sciences, UiT The Arctic University of Norway, Tromsø, Norway Objective: To investigate the relationship between anthropometrics and sprint and agility performance and describe the development of sprint (acceleration and agility performance in 10- to 16-year-old male soccer players. Methods: One hundred and thirty-two participants were divided into three age groups, 10–12 years (mean 10.8±0.50, 13–14 years (mean 13.9±0.50, and 15–16 years (mean 15.5±0.24, with assessment of 20 m sprint with 10 m split time and agility performance related to body height and body mass within groups. Results: In the 10- to 12-year-olds, there were no significant correlations between height, weight, and the performance variables, except for body mass, which was correlated to 10–20 m sprint (r=0.30. In the 13- to 14-year-olds, body height was significantly correlated with 10 m sprint (r=0.50 and 20 m sprint (r=0.52, as well as 10–20 m sprint (r=0.50 and agility performance (r=0.28. In the 15- to 16-year-old group, body height was correlated to 20 m (r=0.38 and 10–20 m (r=0.45 sprint. Body mass was significantly correlated to 10 m spring (r=0.35 in the 13- to 14-year-olds, as well as 20 m (r=0.33 and 10–20 m (r=0.35 sprint in the 15- to 16-year-olds. Conclusion: Height and body mass were significantly correlated with sprint performance in 13- to 16-year-old male soccer players. However, the 10- to 12-year-olds showed no significant relationship between sprint performance and anthropometrics, except for a small correlation in 10–20 m sprint. This may be attributed to maturation, with large differences in body height and body mass due to different patterns in the growth spurt. The agility performance related to anthropometrics was insignificant apart from a moderate correlation in the 13- to 14-year-olds. Keywords: youth soccer, running speed, development, football, puberty, skills
Yildiz, Mustafa; Sahan, Hasan; Tekin, Murat; Ulukan, Mehmet; Mehtap, Bekir
The purpose of this study was to analyse the anger expression styles, the continuous anger and personality types of players who play football in the professional league. The research group consisted of 133 soccer players who are playing in sports teams in the Turkish Super League: Ankara Sport Club, Gençlerbirliği Sports Club and Hacettepe Sports Club in the first league, Turk Telekom sports in the second league, and Keçiören Gücü Sports and Ankarademir Sports playing in the third league in the 2008-2009 football season. The Eysenck personality inventory was modified to Turkish by Bayar in 1983, having been developed by Eysenck and Eysenck in 1975 and the continuous anger-anger style scale (SOTO) was modified to Turkish by Ozer in 1994. The state trait anger scale (STAS) was originally developed by Spielberger in 1983. All these were used on soccer players participating in the study to determine the continuous anger and anger styles in this study. In the interpretation of data, a meaningfulness of p < 0.05, was applied by using regression analysis, the Kruskal Wallis Test, the one-way variance analysis (ANOVA) test and the Tukey test to find the differences among the groups. The SPSS (Statistical Package for Social Sciences) programme was used to find the accounted values and to evaluate the data. According to the results of this study, regarding the education level variable, while there was a meaningful difference between the continuous anger sub-dimension and anger control sub-dimension than continuous anger-anger expression styles, no significant difference was found among personality type sub-dimensions (psychoticism, extrovert, neurotic, false). In addition, a significant relationship was found between psychoticism, extrovert, neurotic, and lie sub-dimensions and the personality type sub-dimensions of professional players' constant anger-anger expression styles.
Gordon, Reno Eron; Kassier, Susanna Maria; Biggs, Chara
Poor hydration compromises performance and heightens the risk of heat stress which adolescents are particularly susceptible to as they produce comparatively larger amount of metabolic heat during exercise. This study determined the hydration status and fluid intake of socio-economically disadvantaged, male adolescent soccer players during training. A pilot study was conducted among 79 soccer players (mean age 15.9 ± 0.8 years; mean BMI 20.2 ± 2.1 kg/m(2)). Hydration status was determined before and after two training sessions, using both urine specific gravity and percent loss of body weight. The type and amount of fluid consumed was assessed during training. A self-administered questionnaire was used to determine the players' knowledge regarding fluid and carbohydrate requirements for soccer training. Players were at risk of developing heat illness during six of the 14 training sessions (60 - 90 minutes in length). Although on average players were slightly dehydrated (1.023 ± 0.006 g/ml) before and after (1.024 ± 0.007 g/ml) training, some were extremely dehydrated before (24%) and after (27%) training. Conversely some were extremely hyperhydrated before (3%) and after training (6%). The mean percent loss of body weight was 0.7 ± 0.7%. The majority did not consume fluid during the first (57.0%) and second (70.9%) training sessions. An average of 216.0 ± 140.0 ml of fluid was consumed during both training sessions. The majority (41.8%) consumed water, while a few (5.1%) consumed pure fruit juice. More than 90% stated that water was the most appropriate fluid to consume before, during and after training. Very few (5.0%) correctly stated that carbohydrate should be consumed before, during and after training. Approximately a quarter were severely dehydrated. Many did not drink or drank insufficient amounts. The players' beliefs regarding the importance of fluid and carbohydrate consumption did not correspond with their practices. A
Castagna, Carlo; Krustrup, Peter; D'Ottavio, Stefano; Pollastro, Carlo; Bernardini, Andrea; Araújo Póvoas, Susana Cristina
The purpose of this study was to examine the reliability and the association with relevant match activities (ecological validity) of an age-adapted field test for intermittent high-intensity endurance known as Yo-Yo intermittent recovery level 1 children test (YYIR1C) in young male soccer players. Twenty-eight young male outfield soccer players (age 11.1±0.9 years, height 142±4.4 cm, body mass 37.0±5.9 kg) with at least 2 years of experience in soccer competitions were tested twice using YYIR1C and an age-adapted competitive small-sided game (i.e., 9v9), 7 days apart in a random order. The YYIR1C performance showed an excellent relative (ICC=0.94) and a good absolute reliability (TEM as %CV=5.1%). Very large and significant associations were found between YYIR1C performance and match high-intensity activity (r=0.53). Large correlations were found between YYIR1C and match sprinting (r=0.42) and high-intensity metabolic power (r=0.46) distances. Match total distance was largely associated with YYIR1C (r=0.30). The results of this study showed that YYIR1C may be considered a valid and reliable field test for assessing intermittent high-intensity endurance in young male soccer players. Due to the relevance of aerobic fitness in youth soccer, future studies testing the sensitiveness of YYIR1C are necessary.
Gouttebarge, Vincent; Backx, Frank J G; Aoki, Haruhito; Kerkhoffs, Gino M M J
Evidence on the prevalence of symptoms related to distress, anxiety/depression or substance abuse/dependence, - typically referred to as symptoms of common mental disorders (CMD) - is lacking in European professional football (soccer). The aims of the present study were to investigate the prevalence of symptoms related to CMD (distress, anxiety/depression, sleeping disturbance, adverse alcohol behaviour, and adverse nutrition behaviour) in professional footballers from five European countries, and to explore associations of the outcome measures under study with life events and career dissatisfaction. A cross-sectional design was used. Questionnaires were distributed among professional footballers by the national players' unions in Finland, France, Norway, Spain and Sweden. The highest prevalence of symptoms related to common mental disorders were 18% for distress (Sweden), 43% for anxiety/depression (Norway), 33% for sleeping disturbance (Spain), 17% for adverse alcohol behaviour (Finland), and 74% for adverse nutrition behaviour (Norway). In Finland, France and Sweden, both life events and career dissatisfaction were associated with distress, anxiety/depression, adverse alcohol behaviour, and adverse nutrition behaviour. Results suggest the need for self-awareness in professional football about common mental disorders and a multidisciplinary approach by the medical team. Key pointsThe highest prevalence of symptoms related to common mental disorders were 18% for distress (Sweden), 43% for anxiety/depression (Norway), 33% for sleeping disturbance (Spain), 17% for adverse alcohol behaviour (Finland), and 74% for adverse nutrition behaviour (Norway).In Finland, France and Sweden, both life events and career dissatisfaction were associated with distress, anxiety/depression, adverse alcohol behaviour, and adverse nutrition behaviour.Our results suggest the need for self-awareness in professional football about common mental disorders and a multidisciplinary approach by
Full Text Available The aim of this study was to compare the effects of two different mixed training programs (optimum power load [OPL] + resisted sprints [RS] and OPL + vertical/horizontal plyometrics [PL] on neuromuscular performance of elite soccer players during a short-term training preseason. Eighteen male professional soccer players took part in this study. The athletes were pair-matched in two training groups: OPL + RS and OPL + PL. Unloaded and resisted sprinting speeds at 5-, 10-, 20-, and 30-m, change of direction (COD speed, and performance in the squat jump (SJ, countermovement jump (CMJ, and horizontal jump (HJ were assessed pre- and post- a 5-week training period. Magnitude based inference with the effect sizes were used for data analysis. A possible increase in the SJ and CMJ heights and a likely increase in the HJ distance were observed in the OPL + PL group. Meaningful improvements were observed in the COD speed test for both training groups comparing pre- and post-measures. In both unloaded and resisted sprints, meaningful decreases were observed in the sprinting times for all distances tested. This study shows that a mixed training approach which comprises exercises and workloads able to produce positive adaptations in different phases of sprinting can be a very effective strategy in professional soccer players. Moreover, the possibility of combining optimum power loads with resisted sprints and plyometrics emerges as a novel and suitable option for coaches and sport scientists, due to the applicability and efficiency of this strength-power training approach.
Rey, Ezequiel; Lago-Peñas, Carlos; Lago-Ballesteros, Joaquín
Tensiomyography is a non-invasive method of neuromuscular assessment used to measure muscle action characteristics, muscle tone, and muscle fiber type, and provides information on acute and chronic responses of muscle to different training loads. The aims of the present study were: to analyse differences in muscle response and mechanical characteristics of two major muscles of the lower extremity in a large group of Spanish soccer players according to playing position, and to provide group norms against which clinical findings may be compared. Data were collected from 78 professional soccer players (age 26.6 ± 4.4 years; height: 179.2 ± 5.3 cm; body mass: 75.8 ± 5.3 kg). Tensiomyography was recorded from the rectus femoris (RF) and biceps femoris (BF) muscles after 2 days without take part in any strenuous exercise or training. Five tensiomyographic parameters were analyzed: maximal displacement (D(m)), contraction time (T(c)), sustain time (T(s)), delay time (T(d)), and half-relaxation time (T(r)). A good to excellent intra-session reliability was found for all contractile parameters (ICC ranged from 0.78 to 0.95). No significant differences between players of any position were observed in absolute values of BF. However, significant differences were observed for T(c), T(r) and T(s) between the different playing positions on RF (P muscles with ability to rapidly generate force during contractions. The neuromuscular profile provided could help in identifying the normative data that are important for the different positions in order to optimize the training and recovery process of each individual player. Copyright © 2012 Elsevier Ltd. All rights reserved.
Noda, Yuka; Iide, Kazuhide; Masuda, Reika; Kishida, Reina; Nagata, Atsumi; Hirakawa, Fumiko; Yoshimura, Yoshitaka; Imamura, Hiroyuki
The purpose of this study was: 1) to collect baseline data on nutrient intake in order to advise athletes about nutrition practices that might enhance performance, and 2) to evaluate the dietary iron intake and blood iron status of Japanese collegiate soccer players. The subjects were 31 soccer players and 15 controls. Dietary information was obtained with a food frequency questionnaire. The mean carbohydrate (6.9 g.kg-1 BW) and protein (1.3 g/kg) intakes of the soccer players were marginal in comparisons with recommended targets. The mean intakes of calcium, magnesium, vitamin A, B1, B2, and C were lower than the respective Japanese recommended dietary allowances (RDAs) or adequate dietary intakes in the soccer players. The mean intakes of green and other vegetables, milk and dairy products, fruits, and eggs were lower than the recommended targets. Thus, we recommended athletes to increase the intake of these foodstuffs along with slight increase in carbohydrate and lean meat. The mean intake of iron was higher than the respective RDA in the soccer players. A high prevalence of hemolysis (71%) in the soccer players was found. None of the soccer players and controls had anemia. Two soccer players had iron depletion, while none was found in the controls. In those players who had iron deficiency, the training load need to be lowered and/or iron intake may be increased.
van der Horst, N
The aim of the studies reported in this thesis was to investigate strategies for the prevention of hamstring injuries. Hamstring injuries are the most prevalent muscle injury in soccer. In spite of efforts to reduce the occurrence of hamstring injuries in soccer, injury rates have not decreased over
Mathisen, Gunnar; Pettersen, Svein Arne
To investigate the relationship between anthropometrics and sprint and agility performance and describe the development of sprint (acceleration) and agility performance in 10- to 16-year-old male soccer players. One hundred and thirty-two participants were divided into three age groups, 10-12 years (mean 10.8±0.50), 13-14 years (mean 13.9±0.50), and 15-16 years (mean 15.5±0.24), with assessment of 20 m sprint with 10 m split time and agility performance related to body height and body mass within groups. In the 10- to 12-year-olds, there were no significant correlations between height, weight, and the performance variables, except for body mass, which was correlated to 10-20 m sprint (r=0.30). In the 13- to 14-year-olds, body height was significantly correlated with 10 m sprint (r=0.50) and 20 m sprint (r=0.52), as well as 10-20 m sprint (r=0.50) and agility performance (r=0.28). In the 15- to 16-year-old group, body height was correlated to 20 m (r=0.38) and 10-20 m (r=0.45) sprint. Body mass was significantly correlated to 10 m spring (r=0.35) in the 13- to 14-year-olds, as well as 20 m (r=0.33) and 10-20 m (r=0.35) sprint in the 15- to 16-year-olds. Height and body mass were significantly correlated with sprint performance in 13- to 16-year-old male soccer players. However, the 10- to 12-year-olds showed no significant relationship between sprint performance and anthropometrics, except for a small correlation in 10-20 m sprint. This may be attributed to maturation, with large differences in body height and body mass due to different patterns in the growth spurt. The agility performance related to anthropometrics was insignificant apart from a moderate correlation in the 13- to 14-year-olds.
Marwan, Yousef; Behbehani, Abdullah; Al-Mousawi, Abdullah; Mulla-Juma'a, Ali; Sadeq, Husain; Shah, Nasrah
To assess a 12-month period and the lifetime prevalence of sports injuries among male athletes according to type of sport, type of injury and its seriousness, and to examine the association of injuries with sociodemographic, lifestyle and preventive factors. In this cross-sectional study, we approached 475 professional athletes participating in ball sports, aged 15 years and older, from 5 sports clubs in Kuwait. Of them, 452 responded. Four ball games--football (soccer), basketball, handball and volleyball--were included. Data were collected through a self-administered questionnaire. Bivariate and multivariate relationships between associated factors and experience of injury were tested by using χ(2) and logistic regression. The overall 12-month and lifetime prevalence of sports injuries were 73.8 and 89.8%, respectively. Prevalence was highest among volleyball athletes (79%) and lowest among football (soccer) athletes (69%). Lower limbs (73.1%) were the most common site of injuries and joint injuries (43.6%) were the most common type. For the most recent injury, 138 (42%) of athletes took more than 10 days off practice. Compared to volleyball, football (soccer) and handball athletes were 2.9 times (95% CI: 1.3-6.3) and 3.4 times (95% CI: 1.5-7.8) more likely to take more than 10 days off practice. Athletes who sometimes wore protective gears were 3.1 times (95% CI: 1.7-5.8) more likely to report an injury compared with those who never wore protective gears (p injuries are highly prevalent among professional athletes in Kuwait. Future studies are needed to provide guidelines for interventions that may reduce such injuries. Copyright © 2011 S. Karger AG, Basel.
Thorborg, Kristian; Branci, Sonia; Nielsen, Peter Martin
BACKGROUND: Adductor-related pain is the most common clinical finding in soccer players with groin pain and can be a long-standing problem affecting physical function and performance. Hip adductor weakness has been suggested to be associated with this clinical entity, although it has never been...... investigated. PURPOSE: To investigate whether isometric and eccentric hip strength are decreased in soccer players with adductor-related groin pain compared with asymptomatic soccer controls. The hypothesis was that players with adductor-related groin pain would have lower isometric and eccentric hip adduction...... strength than players without adductor-related groin pain. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Male elite and subelite players from 40 teams were contacted. In total, 28 soccer players with adductor-related groin pain and 16 soccer players without adductor-related groin pain...
Castellote-Caballero, Yolanda; Valenza, Marie Carmen; Martín-Martín, Lydia; Cabrera-Martos, Irene; Puentedura, Emilio J; Fernández-de-Las-Peñas, César
To compare the short-term effects of a neurodynamic sliding technique versus control condition on hamstring flexibility in healthy, asymptomatic male soccer players. Twenty-eight young male soccer players from Palencia, Spain (mean age 20.7 yrs ± 1.0, range 19-22) with decreased hamstring muscle flexibility. Subjects were randomly assigned to one of two groups: neurodynamic sliding intervention or no intervention control. Each subject's dominant leg was measured for straight leg raise (SLR) range of motion (ROM) pre- and post-intervention. Subjects received interventions as per group allocation over a 1 week period. Data were analyzed with a 2 (intervention: neurodynamic and control) × 2 (time: pre and post) factorial ANOVA with repeated measures and appropriate post-hoc analyses. A significant interaction was observed between intervention and time for hamstring extensibility, F(1,26) = 159.187, p sliding technique can increase hamstring flexibility in healthy, male soccer players. Copyright © 2012 Elsevier Ltd. All rights reserved.
Zebis, Mette K; Andersen, Lars L; Ellingsgaard, Helga
Knee joint injuries are a serious issue in soccer. The ability to protect the knee from injury depends largely on the strength of the hamstring relatively to the quadriceps, that is, a low hamstring/quadriceps (H/Q) strength ratio is suggested as a risk factor. Although maximal muscle strength (MVC....../Q strength ratio in elite soccer players. Twenty-three elite soccer players (11 women, 12 men) performed maximal voluntary static contraction for the hamstring and quadriceps in an isokinetic dynamometer, from which the maximal muscles strength (MVC) and RFD were extracted. Test-retest reliability...
Manley, A J; Greenlees, I A; Smith, M J; Batten, J; Birch, P D J
The present study examined the impact of reputation information on athletes' behavioral responses to coaches within a naturalistic, field-based setting. Using a between-group design, male soccer players (n = 35) were assigned to one of three experimental conditions (i.e., experienced reputation, inexperienced reputation, no reputation) prior to taking part in a coaching session delivered by an unknown coach. Participants' behaviors indicative of attention to coach instruction, effort and persistence, and willingness to participate in demonstrations were video recorded throughout the coaching session. Multivariate analyses of variance revealed that participants in the experienced reputation condition exhibited significantly greater attention to coach instruction, and greater effort and persistence during free practice than participants in the inexperienced reputation condition. Results related to participants' willingness to participate in demonstrations failed to yield any significant differences. The results provide further evidence to support the contention that athletes use reputation information as a basis for their initial expectancies of coaches, and such expectancies have the potential to influence athletes' behavior during coach-athlete interactions. The findings also indicate that expectancies based on positive information may be more powerful than negatively framed expectancies, and can be harnessed by coaches as a means of developing effective relationships with their athletes. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Castagna, Carlo; Francini, Lorenzo; Krustrup, Peter; Fenarnandes-da-Silva, Juliano; Póvoas, Susana C A; Bernardini, Andrea; D'Ottavio, Stefano
The aim of this study was to examine the usefulness and reliability characteristics of a repeated sprint ability test considering 5 line sprints of 30-m interspersed with 30-s of active recovery in non-elite outfield young male soccer players. Twenty-six (age 14.9±1.2 years, height 1.72±0.12 cm, body mass 62.2±5.1 kg) players were tested 48 hours and 7 days apart for 5x30-m performance over 5 trials (T1-T5). Short- (T1-T2) and long-term reliability (T1-T3-T4-T5) were assessed with Intraclass Correlation Coefficient (ICC) and with typical error for measurement (TEM). Short- and long-term reliability ICCs and TEMs for total sprint time and best sprint performance were nearly perfect and satisfactory, respectively. Usefulness (as smallest worthwhile change and TEM ratio) resulted acceptable (i.e =1) and good (i.e >1) for total sprint time and best sprint performance, respectively. The present study revealed that the 5x30-m sprint test is a reliable field test in the short and long-term when the sum of sprint times and the best sprint performance are considered as outcome variables. Sprint performance decrements variables showed large variability across trials.
Anderson, Liam; Naughton, Robert J; Close, Graeme L; Di Michele, Rocco; Morgans, Ryland; Drust, Barry; Morton, James P
The daily distribution of macronutrient intake can modulate aspects of training adaptations, performance and recovery. We therefore assessed the daily distribution of macronutrient intake (as assessed using food diaries supported by the remote food photographic method and 24 h recalls) of professional soccer players (n=6) of the English Premier League during a 7-day period consisting of two match days and five training days. On match days, average carbohydrate (CHO) content of the pre-match (0.05) though such intakes were lower than contemporary guidelines considered optimal for pre-match CHO intake and post-match recovery. On training days, we observed a skewed and hierarchical approach (Plunch (0.6 g.kg(-1))>breakfast (0.3 g.kg(-1))>evening snacks (0.1 g.kg(-1)). We conclude players may benefit from consuming greater amounts of CHO in both the pre-match and post-match meals so as to increase CHO availability and maximize rates of muscle glycogen re-synthesis, respectively. Furthermore, attention should also be given to ensuring even daily distribution of protein intake so as to potentially promote components of training adaptation.
Full Text Available Home advantage in team sports has an important role in determining the outcome of a game. The aim of the present study was to identify the soccer game- related statistics that best discriminate home and visiting teams according to the team quality. The sample included all 380 games of the Spanish professional men's league. The independent variables were game location (home or away and the team quality. Teams were classified into four groups according to their final ranking at the end of the league. The game-related statistics registered were divided into three groups: (i variables related to goals scored; (ii variables related to offense and (iii variables related to defense. A univariate (t-test and Mann-Whitney U and multivariate (discriminant analysis analysis of data was done. Results showed that home teams have significantly higher means for goal scored, total shots, shots on goal, attacking moves, box moves, crosses, offsides committed, assists, passes made, successful passes, dribbles made, successful dribbles, ball possession, and gains of possession, while visiting teams presented higher means for losses of possession and yellow cards. In addition, the findings of the current study confirm that game location and team quality are important in determining technical and tactical performances in matches. Teams described as superior and those described as inferior did not experience the same home advantage. Future research should consider the influence of other confounding variables such as weather conditions, game status and team form
Hagen, Marco; Abraham, Christoph; Ficklscherer, Andreas; Lahner, Matthias
Femoroacetabular impingement (FAI) is accompanied by increased hip alpha angles, in particular in athletes with high impact sports. The aim of our study was to investigate the dynamic function of the foot during walking in male soccer players with increased versus normal alpha angles. Plantar pressures of 20 injury-free male soccer players were recorded during barefoot walking at 1.6 m/s. Ten subjects had bilaterally increased (>55°) (IA) and ten subjects normal (<50°) hip alpha angles (NA). Both standing and kicking leg were analyzed. Compared to NA, IA showed lower force-time-integrals (-23%; p< 0.01), pressure-time-integrals (-29%; p< 0.001) and relative loads (p< 0.05) under the heel. In IA contact area of the hallux is about 13% (p< 0.05) reduced. In IA relative loads are increased under the lateral midfoot (p< 0.05) and the second toe (p< 0.05). Higher loading of the lateral midfoot is also reflected in the increased force-time integral (+33%; p< 0.001). No differences between legs and no interactions, indicating a specifity in kicking or standing leg, are found. Compared to NA, soccer players with IA show a forward shifting of the center of pressure which indicates a compensatory mechanism of the foot during walking.
Gordon, Reno Eron; Kassier, Susanna Maria; Biggs, Chara
.... The type and amount of fluid consumed was assessed during training. A self-administered questionnaire was used to determine the players' knowledge regarding fluid and carbohydrate requirements for soccer training...
Full Text Available AbstractSports foundations aiming at promoting sports activities partly outline the nonprofit area with specific concern. This study attempts to know the functions, general interests of professional soccer foundations in Spain, to describe their main characteristics and to ascertain if there are significant differences among them, according to their descriptive features. A document survey and analysis was carried out, with an assistance of own establishment of documental database. The findings not only indicate a significant difference between the classification of Spanish soccer foundations and their antiquities, but also manifest the tendency of the existence of physical person in members of founders with regard to its antiquity. The results of the present work implied that there were great dissimilarities of the elaboration of regulations depending on different regions in Spain.ResumenDentro del sector asociativo, las fundaciones deportivas tienen el propósito específico de desarrollar actividades de promoción deportiva. Este estudio intentó conocer las funciones, e intereses generales, de las fundaciones del fútbol profesional en España, describiendo sus principales características y comprobando si existían diferencias significativas entre ellos. Se utilizó el análisis documental y se realizó una base de datos documental. Los resultados indicaron que existía una diferencia significativa entre los diferentes tipos de clasificación de una fundación del fútbol profesional en España en función de la antigüedad de dicha fundación. También se manifestó una tendencia de la existencia de personas físicas o no, dentro del tipo de fundadores, en función de la antigüedad de la organización. La presente investigación pone de manifiesto la gran variedad en las legislaciones dependiendo de la comunidad autónoma de origen.http://dx.doi.org/10.5232/ricyde2013.03106
Barbosa, Carlos V da Silva; Silva, Alexandre S; de Oliveira, Caio V C; Massa, Nayara M L; de Sousa, Yasmim R F; da Costa, Whyara K A; Silva, Ayice C; Delatorre, Plínio; Carvalho, Rhayane; Braga, Valdir de Andrade; Magnani, Marciane
Nutritional intervention with antioxidants rich foods has been considered a strategy to minimize the effects of overtraining in athletes. This experimental, randomized, and placebo-controlled study evaluated the effects of consumption of sesame ( Sesamum indicum L.) on muscle damage markers, oxidative stress, systemic inflammation, and aerobic performance in male semi-professional soccer players. Twenty athletes were randomly assigned to groups that received 40 g (two tablespoons) per day of sesame or a placebo during 28 days of regular training (exposed to routine training that includes loads of heavy training in the final half of the season). Before and after intervention, creatine kinase (CK), lactate dehydrogenase (LDH), malondialdehyde (MDA), superoxide dismutase (SOD), C-reactive protein (hs-CRP), and aerobic capacity were evaluated. Before intervention, a physiologic imbalance was noted in both groups related to CK and LDH levels. Sesame intake caused a reduction of CK (19%, p sesame consumption may reduce muscle damage and oxidative stress while improving the aerobic capacity in soccer players.
Ive da Luz Canhadas
Full Text Available The objective of this study was to determine anthropometric and physical fitness characteristics of Brazilian male children and adolescents at the beginning of soccer training. In this study, 282 male soccer players ranging in age from 10 to 13 years were evaluated. The athletes participated in a formal soccer training program 3 times per week, with each training lasting 3 hours. Anthropometric and physical fitness parameters were obtained. The boys were divided into age classes and prevalence data were analyzed using Pearson’s chi-square test. Parametric data were compared by one-way ANOVA or the Kruskal-Wallis test, when necessary. The results are expressed as the mean ± standard deviation and a p value <0.05 was considered to be significant. Growth, development, body adiposity and physical fitness characteristics were adequate and proportional to age among the boys studied (p<0.05. It was concluded that anthropometric and physical fitness characteristics of young male elite soccer players improve with and are proportional to age. Children and adolescents greatly benefit from regular physical activity. The present results show that young male soccer players present adequate anthropometric conditions and physical fitness prior to the initiation of formal training at soccer clubs.
Harøy, Joar; Thorborg, Kristian; Serner, Andreas
BACKGROUND: The FIFA 11+ was developed as a complete warm-up program to prevent injuries in soccer players. Although reduced hip adduction strength is associated with groin injuries, none of the exercises included in the FIFA 11+ seem to specifically target hip adduction strength. PURPOSE......: To investigate the effect on eccentric hip adduction strength of the FIFA 11+ warm-up program with or without the Copenhagen adduction exercise. STUDY DESIGN: Randomized controlled trial; Level of evidence, 1. METHODS: We recruited 45 eligible players from 2 U19 elite male soccer teams. Players were randomized...... into 2 groups; 1 group carried out the standard FIFA 11+ program, while the other carried out the FIFA 11+ but replaced the Nordic hamstring exercise with the Copenhagen adduction exercise. Both groups performed the intervention 3 times weekly for 8 weeks. Players completed eccentric strength and sprint...
Francimara Budal Arins
Full Text Available > This study aimed to characterize physiological responses of indoor soccer (futsal professional players to training sessions, according to playing position. The sample was composed by five players ( X =23.9±3.0 yrs of an adult professional futsal team from Florianópolis, SC, Brazil. The athletes performed a maximal exercise test for measuring oxygen consumption, heart rate (HR and respiratory quotient (RQ, variables used to create regression equations for energy expenditure (EE, kcal prediction and to estimate relative work intensity (% max HR. During the sessions, HR was measured with a S610i Polar® monitor. The results showed that the goalkeeper played at 60% to 70% max HR. The mid-fi elders and the attacker worked at more intense levels (81% to 100%, while the defender varied the intensity at intermediate exercise range (71% to 90%. Total EE was similar among mid-fi elders and attacker ( X =339.5 kcal, while the defender presented lower values ( X =255.0 kcal. The goalkeeper had the lowest EE ( X =106.9 kcal. The results agreed with those reported in soccer studies and facilitate planning and control of an individualized training program according to playing position. ABSTRACT Este estudo objetivou caracterizar as respostas fi siológicas de atletas profissionais de futsal durante o treinamento coletivo, de acordo com a posição tática desempenhada. A amostra foi composta pelos cinco jogadores titulares ( X =23,9±3,0 anos de uma equipe de futsal masculino profi ssional adulto da cidade de Florianópolis, SC. Os atletas foram avaliados por um teste ergoespirométrico máximo, que forneceu o consumo de oxigênio, a freqüência cardíaca (FC e o quociente respiratório (RQ, valores utilizados para gerar equações de regressão para estimativa do gasto calórico (GCal e da intensidade do trabalho (expressa em % FC máxima predita pela idade (% FC máx. Durante os coletivos, a FC foi mensurada com um monitor Polar modelo S610i®. Os
Nicole M. Sauls
Full Text Available Objective: The purpose of this investigation was to determine the differences in collegiate and recreationally trained soccer players in sprint, vertical jump, and balance performance. Methods: Twenty-one soccer players, twelve Division II collegiate and nine recreationally trained volunteered to participate. Session one acted as a familiarization day, where the participants were familiarized with testing day protocols. During testing day, participants performed a dynamic warm-up, followed by balance measurements, three countermovement vertical jumps, and pro-agility shuttle test. Results: There were no significant (p>0.05 differences between groups in the all balance variables. Collegiate soccer players had a significantly (p0.05 differences in groups in all other variables. Conclusion: These results indicate that collegiate, Division II, soccer players had greater vertical jumping and sprinting velocities when compared to recreationally trained soccer players. These results may have been impacted by the lack of resistance training background in either of the two groups. With the addition of more time on a collegiate resistance training program, it is very likely the Division II athletes will see a significant increase in all balance, sprint, and vertical jump performance measures compared to recreationally trained players who receive little to no specialized resistance training.
Campos-Vazquez, Miguel A; Toscano-Bendala, Francisco J; Mora-Ferrera, José C; Suarez-Arrones, Luis J
The aim of this study was to examine the effects of accumulated internal training load (ITL) during the preseason (4 weeks) on changes in the intermittent performance, in a professional soccer team. Twelve professionals soccer players (Mean ± SD age: 27.7 ± 4.3 years; height: 177.1 ± 6.2 cm; body mass: 73.1 ± 5.2 kg; % body fat [Faulkner]: 10.2 ± 1.2) belonging to a Spanish second division team (2013-2014) participated in this study. The 30-15 intermittent fitness test was performed before and after the preseason, and the speed for the last period completed by each player was recorded (VIFT). During the preseason, the team alternated practice of training sessions (TRNs) with friendly matches (FMs). Session rating of perceived exertion (sRPE), heart rate (HR), and HR reserve were analyzed every TRN and FM to calculate ITL (ITL: sRPE-TL, Edward's-TL and Edward's-TLres). The players' VIFT substantially increased after the preseason period (20.1 ± 0.8 vs. 21.1 ± 0.8 km·h; effect size [ES] = 1.15 ± 0.25; almost certainly). The average value of sRPE throughout FMs was substantially greater than the value of the TRNs (7.4 ± 0.9 vs. 5.25 ± 0.2; ES = 2.31 ± 2.45; almost certainly). sRPE-TL, practice volume, and sum of RPE during the preseason were positively and largely correlated (r = 0.70-0.75) with changes on intermittent performance. No relationships were found between HR-derived measures of exercise load and changes on intermittent fitness. The present results suggest that practice volume and subjective measures of TL, related better than HR-based TL methods to changes on intermittent performance after the preseason, in professional soccer players.
Rutkowska Katarzyna; Bergier Józef
Many sports (for instance soccer) are stereotypically perceived as a male activity. Even so, more and more women decide to become competitive athletes. Since the theory of sport requires comprehensive explanations and the practice of sport needs clear guidelines, interdisciplinary studies into the nature of sport, including its psychological aspects, are necessary. Analysing the psychological profile of female soccer players, particularly those who are about to become professional athletes, c...
Steca, P; Pala, A Norcini; Greco, A; Monzani, D; D'Addario, M
Psychometric properties of the Group Environment Questionnaire were investigated in a large sample of soccer (n = 222) and professional basketball players (n = 375). Confirmatory factor analysis was performed both on the total sample and on the two subsamples through a multi-group approach; associations between cohesion and the duration of belonging to the team were also explored. Results confirmed the four-factor structure proposed by Carron's original model even though some items with low loadings were eliminated. No significant associations were found between team cohesion and the duration of belonging to the team.
Lockie, Robert G; Moreno, Matthew R; Orjalo, Ashley J; Stage, Alyssa A; Liu, Tricia M; Birmingham-Babauta, Samantha A; Hurley, Jillian M; Torne, Ibett A; Beiley, Megan D; Risso, Fabrice G; Davis, DeShaun L; Lazar, Adrina; Stokes, John J; Giuliano, Dominic V
Repeated-sprint ability (RSA) in essential for soccer. Important considerations when assessing RSA is whether there are differences between positions (defenders, midfielders, forwards), and what physiological characteristics may contribute to RSA. This has not been assessed in collegiate male players. Eighteen Division I male field players from one school performed several performance tests. The RSA test involved 7 x 30-m sprints completed on 20-s cycles. Measurements included total time (TT), and performance decrement (percent change in time from the first to last sprint; PD). Subjects also completed tests of lower-body power (vertical [VJ] and standing broad [SBJ] jump); linear (30-m sprint; 0-5, 0-10, 0-30 m intervals) and change-of-direction (505) speed; and soccer-specific endurance (Yo-Yo Intermittent Recovery Test Level 2; YYIRT2). A one-way ANOVA (p RSA TT and PD with the other tests. There were no significant between-position differences for any test. There were large effects for the faster right-leg 505 and greater YYIRT2 distance for midfielders compared to defenders and forwards. Nonetheless, no between-position differences in RSA TT and PD were documented. There were relationships between RSA TT and the VJ (r = -0.59), SBJ (r = -0.61), 0-10 m (r = 0.64) and 0-30 m (r = 0.83) sprint intervals. There were no significant correlations for RSA PD. Male field players from one collegiate soccer team can demonstrate similar RSA across different positions. Greater lower-body power and sprinting speed could augment RSA.
Harry, John R; Barker, Leland A; Mercer, John A; Dufek, Janet S
Harry, JR, Barker, LA, Mercer, JA, and Dufek, JS. Vertical and horizontal impact force comparison during jump landings with and without rotation in NCAA Division I male soccer players. J Strength Cond Res 31(7): 1780-1786, 2017-There is a wealth of research on impact force characteristics when landing from a jump. However, there are no data on impact forces during landing from a jump with an airborne rotation about the vertical axis. We examined impact force parameters in the vertical and horizontal axes during vertical jump (VJ) landings and VJ landings with a 180° rotation (VJR). Twenty-four Division I male soccer players performed 3 VJ and VJR landings on a dual-force platform system. Paired-samples t-tests (α = 0.05) compared differences in the first (F1) and second (F2) peak vertical ground reaction forces, times to F1 (tF1), F2 (tF2), and the end of the impact phase, vertical impulse, and anterior-posterior and medial-lateral force couples. Effect sizes (ES; large >0.8) were computed to determine the magnitude of the differences. Lower jump height (41.60 ± 4.03 cm, VJ landings; 39.40 ± 4.05 cm, VJR landings; p = 0.002; ES = 0.39), greater F2 (55.71 ± 11.95 N·kg, VJ; 68.16 ± 14.82 N·kg; p jump with 180° airborne rotation is different than landing from a jump without an airborne rotation. Male Division I soccer players could benefit from increasing the volume of VJR landings during training to address the differences in jump height and force parameters compared with VJ landings.
Shalfawi, Shaher A.I.; Ingebrigtsen, Jørgen; Dillern, Thomas; Tønnessen, Espen; Delp, Tor Kristoffer; Enoksen, Eystein
The purpose of this study was to investigate the effect of eight-week repeated sprint training program on maximum sprinting speed, endurance sprinting speed, jump height and the ability to repeat and recover from high-intensity exercise (Yo-Yo IR1). Fifteen young, well-trained, elite male soccer players aged (±SD) 16.3 ±0.5 years, body mass 68.1 ±9.4 kg, and stature 178.5 ±7.3 cm, volunteered to participate in this study. All subjects were tested on 40 m sprint, 10x40 m repeated sprint, 3–6–9...
Handberg, Charlotte; Midtgaard, Julie; Nielsen, Claus Vinther
Purpose: The purpose of this study is to describe and interpret the attitudes and conduct of hospital healthcare professionals (HCPs) in association with male cancer survivors and their municipal rehabilitation participation. Design: Ethnographic fieldwork was conducted, consisting of participant...
Suarez-Arrones, L; Torreño, N; Requena, B; Sáez De Villarreal, E; Casamichana, D; Barbero-Alvarez, J C; Munguía-Izquierdo, D
The aim was to quantify for the first time the physical and physiological profile of professional soccer players in official games using GPS and heart rate (HR) response. Thirty professional soccer players were investigated during a half in competitive club level matches (N.=348) using GPS devices. The relative total distance was 118.9±10.7 m∙min(-1) and player's Work-To-Rest Ratio was 2.1:1. Defenders covered the lowest total distance, while Second-Strikers (2(nd)S) and Wide-Midfielders (W-MD) traveled the greatest total distance. Defenders presented the lowest Work-To-Rest Ratio values. Playing position also impacted on all sprinting performance results, except in average sprint distance and time of sprint. The number of sprints and repeated-sprint sequences recorded by the W-MD and Strikers (S) were significantly greater than any other group. The average HR recorded was 87.1%HRmax and the relationship between the external and internal load value (Effindex) was 1.4 with significant differences in both between playing positions. W-MD recorded a significantly smaller average HR than any other group and Centre-Backs showed a significantly smaller Effindex value than any other group. Conversely, W-MD showed a significantly greater Effindex value than any other group, except the 2(nd)S. This study has verified a number of statistically significant differences between the different playing positions. Coaches should be focused on the specific physical and physiological requirements of the playing positions to optimize the training prescription in soccer. The relationships between external and internal load measures among position-specific indicates that players with less overall running performance during match-play were the worst in Effindex.
Camila C. Greco
Full Text Available Muscle strength imbalance can be an important factor in hamstrings muscle strain. A hamstrings/quadriceps (H/Q strength ratio based on concentric peak torque values (Hcon:Qcon has traditionally been used to describe the potential for knee-joint destabilization. Because certain standard actions in soccer are explosive, the analysis of the H/Q strength ratio based on the rate of torque development (Hrtd:Qrtd might also be useful in the evaluation of joint stability. The objective of this study was to compare the Hrtd:Qrtd between professional soccer players with heterogeneous values of Hcon:Qcon. Thirty-nine professional soccer players took part in the following procedures on different days: 1 Familiarization session with the isokinetic dynamometer, and 2 Two maximal isometric actions and five maximal concentric actions at 60°·s-1 for hamstrings (H and quadriceps (Q. Participants were ranked according to their Hcon:Qcon ratio. The median third was excluded to form a high torque group (HTG, and a low torque group (LTG. Peak isometric (H and concentric (H and Q torques and rate of torque development (H were significantly greater in the HTG group. Similarly, Hcon:Qcon (0.68 ± 0.02 vs. 0.52 ± 0.03 and Hrtd:Qrtd (0.54 ± 0.12 vs. 0.43 ± 0.16 were significantly greater in the HTG group than in the LTG group. There was no significant correlation between Hcon:Qcon and Hrtd:Qrtd. It can be concluded that Hcon:Qcon and Hrtd:Qrtd are determined, but not fully defined, by shared putative physiological mechanisms. Thus, the physiologic and clinical significance of Hcon:Qcon and Hrtd:Qrtd to an athlete's individual evaluation might be different
Briggs, Marc A.; Rumbold, Penny L. S.; Cockburn, Emma; Russell, Mark; Stevenson, Emma J.
Collecting accurate and reliable nutritional data from adolescent populations is challenging, with current methods providing significant under-reporting. Therefore, the aim of the study was to determine the accuracy of a combined dietary data collection method (self-reported weighed food diary, supplemented with a 24-h recall) when compared to researcher observed energy intake in male adolescent soccer players. Twelve Academy players from an English Football League club participated in the study. Players attended a 12 h period in the laboratory (08:00 h–20:00 h), during which food and drink items were available and were consumed ad libitum. Food was also provided to consume at home between 20:00 h and 08:00 h the following morning under free-living conditions. To calculate the participant reported energy intake, food and drink items were weighed and recorded in a food diary by each participant, which was supplemented with information provided through a 24-h recall interview the following morning. Linear regression, limits of agreement (LOA) and typical error (coefficient of variation; CV) were used to quantify agreement between observer and participant reported 24-h energy intake. Difference between methods was assessed using a paired samples t-test. Participants systematically under-reported energy intake in comparison to that observed (p < 0.01) but the magnitude of this bias was small and consistent (mean bias = −88 kcal·day−1, 95% CI for bias = −146 to −29 kcal·day−1). For random error, the 95% LOA between methods ranged between −1.11 to 0.37 MJ·day−1 (−256 to 88 kcal·day−1). The standard error of the estimate was low, with a typical error between measurements of 3.1%. These data suggest that the combined dietary data collection method could be used interchangeably with the gold standard observed food intake technique in the population studied providing that appropriate adjustment is made for the systematic under-reporting common to such
Erickson, Brandon J; Harris, Joshua D; Cvetanovich, Gregory L; Bach, Bernard R; Bush-Joseph, Charles A; Abrams, Geoffrey D; Gupta, Anil K; McCormick, Frank M; Cole, Brian J
Anterior cruciate ligament (ACL) rupture is a significant injury in male Major League Soccer (MLS) players in the United States. To determine (1) return-to-sport (RTS) rate in MLS following ACL reconstruction (ACLR), (2) timing of RTS, (3) performance upon RTS, and (4) the difference in RTS and performance between players who underwent ACL reconstruction (ACLR) and controls. Case-control study; Level of evidence, 3. MLS players undergoing ACLR between 1996 and 2012 were evaluated. Player data were extracted from publically available sources. All demographic data were analyzed. A control group of players matched by age, body mass index (BMI), sex, position, performance, and MLS experience (occurred at 2.6 years into career, designated "index year") was selected from the MLS during the same years as those undergoing ACLR. The RTS and performance in the MLS were analyzed and compared between cases and controls. Student ttests were performed for analysis of within- and between-group variables. A total of 52 players (57 knees) that met inclusion criteria underwent ACLR while in the MLS. Mean player age was 25.6 ± 3.98 years. Forty players were able to resume play (77%). Of the 40 players (45 knees), 38 (43 knees; 95%) resumed play the season following ACLR (mean, 10 ± 2.8 months after surgery). Mean career length in the MLS after ACLR was 4.0 ± 2.8 years. The revision rate was 10%. There was a significant increase in the incidence of ACL tears in the MLS by year (P Performance in the MLS upon RTS after ACLR was not significantly different versus preinjury. There was no significant difference in survival in the MLS between cases and controls after ACLR or index year. The only significant performance differences between cases and controls were that cases had significantly greater shots taken per season (P= .005) and assists (P= .005) than did controls after the index year. There is a high RTS rate in the MLS following ACLR. Nearly all players resumed play the season
Marc A. Briggs
Full Text Available Collecting accurate and reliable nutritional data from adolescent populations is challenging, with current methods providing significant under-reporting. Therefore, the aim of the study was to determine the accuracy of a combined dietary data collection method (self-reported weighed food diary, supplemented with a 24-h recall when compared to researcher observed energy intake in male adolescent soccer players. Twelve Academy players from an English Football League club participated in the study. Players attended a 12 h period in the laboratory (08:00 h–20:00 h, during which food and drink items were available and were consumed ad libitum. Food was also provided to consume at home between 20:00 h and 08:00 h the following morning under free-living conditions. To calculate the participant reported energy intake, food and drink items were weighed and recorded in a food diary by each participant, which was supplemented with information provided through a 24-h recall interview the following morning. Linear regression, limits of agreement (LOA and typical error (coefficient of variation; CV were used to quantify agreement between observer and participant reported 24-h energy intake. Difference between methods was assessed using a paired samples t-test. Participants systematically under-reported energy intake in comparison to that observed (p < 0.01 but the magnitude of this bias was small and consistent (mean bias = −88 kcal·day−1, 95% CI for bias = −146 to −29 kcal·day−1. For random error, the 95% LOA between methods ranged between −1.11 to 0.37 MJ·day−1 (−256 to 88 kcal·day−1. The standard error of the estimate was low, with a typical error between measurements of 3.1%. These data suggest that the combined dietary data collection method could be used interchangeably with the gold standard observed food intake technique in the population studied providing that appropriate adjustment is made for the systematic under
Jaspers, Arne; Beéck, Tim Op De; Brink, Michel S; Frencken, Wouter G P; Staes, Filip; Davis, Jesse J; Helsen, Werner F
Machine learning may contribute to understanding the relationship between the external load and internal load in professional soccer. Therefore, the relationship between external load indicators and the rating of perceived exertion (RPE) was examined using machine learning techniques on a group and individual level. Training data were collected from 38 professional soccer players over two seasons. The external load was measured using global positioning system technology and accelerometry. The internal load was obtained using the RPE. Predictive models were constructed using two machine learning techniques, artificial neural networks (ANNs) and least absolute shrinkage and selection operator (LASSO), and one naive baseline method. The predictions were based on a large set of external load indicators. Using each technique, one group model involving all players and one individual model for each player was constructed. These models' performance on predicting the reported RPE values for future training sessions was compared to the naive baseline's performance. Both the ANN and LASSO models outperformed the baseline. Additionally, the LASSO model made more accurate predictions for the RPE than the ANN model. Furthermore, decelerations were identified as important external load indicators. Regardless of the applied machine learning technique, the group models resulted in equivalent or better predictions for the reported RPE values than the individual models. Machine learning techniques may have added value in predicting the RPE for future sessions to optimize training design and evaluation. Additionally, these techniques may be used in conjunction with expert knowledge to select key external load indicators for load monitoring.
Gay-Escoda, Cosme; Vieira-Duarte-Pereira, Dario-Miguel; Ardèvol, Jordi; Pruna, Ricard; Fernandez, Javier; Valmaseda-Castellón, Eduard
The objective of this study was to evaluate the oral health status of professional soccer players of F.C. Barcelona and its relation to the incidence of sport lesions. Thirty professional soccer players were consecutively evaluated in the seasons 2003/4, 2004/5 and 2005/6. A research protocol to assess their oral health was developed. DMFT, Quigley & Hein plaque index (PI), Löe & Silness gingival index (GI), World Health Organization malocclusion index, Ramfjord teeth probing pocket depth (PPD), TMJ examination and history of dental trauma were recorded. All physical injuries sustained by players during the season were documented from F.C. Barcelona medical services. Mean DMFT score was 5.7 (SD 4.1), Quigley & Hein plaque index score was 2.3 (SD 1.1), Löe & Silness gingival index was 1.1 (SD 0.8), and periodontal pocket depth was 1.9 mm (SD 0.3). Pearson's analysis showed a significant correlation between PI and GI (pmedical follow-up, have significant oral health problems such as untreated caries, gingivitis or malocclusion, and suffer dental trauma as a result of sports activities. Their physical condition could also be associated to oral health.
Heleno, Lucas Rafael; da Silva, Rubens A; Shigaki, Leonardo; Araújo, Cynthia Gobbi Alves; Coelho Candido, Cristiane Regina; Okazaki, Victor Hugo Alves; Frisseli, Ariobaldo; Macedo, Christiane de S Guerino
Sensory motor training programs are used in the rehabilitation and prevention of injuries among soccer players. Inconsistencies are found in the literature regarding the duration of the protocols and the exercises and equipment used. To evaluate the benefits of a five-week sensory motor training program on the functional performance and postural control of young soccer players. The study sample comprised 22 young male soccer players who were evaluated using: the Figure-of-Eight Test (F8), Side Hop Test (SHT), Star Excursion Balance Test (SEBT), and a force platform. The players were randomly divided into a control group (N = 10), who continued their soccer practice sessions and an intervention group (N = 12), who continued their soccer practice sessions and were also enrolled in a supervised five-week sensory motor training program. After the five-week training program, the intervention group obtained significant results in the F8, SHT and SEBT, as well as in the following parameters: area of pressure of sway center (COP), mean velocity and mean frequency of COP. The five-week sensory motor training program, carried out with easily available and low cost equipment, was effective at improving functional performance and postural control in young soccer players. Copyright Â© 2016 Elsevier Ltd. All rights reserved.
Jaspers, Arne; Brink, Michel S; Probst, Steven G M; Frencken, Wouter G P; Helsen, Werner F
In professional senior soccer, training load monitoring is used to ensure an optimal workload to maximize physical fitness and prevent injury or illness. However, to date, different training load indicators are used without a clear link to training outcomes. The aim of this systematic review was to identify the state of knowledge with respect to the relationship between training load indicators and training outcomes in terms of physical fitness, injury, and illness. A systematic search was conducted in four electronic databases (CINAHL, PubMed, SPORTDiscus, and Web of Science). Training load was defined as the amount of stress over a minimum of two training sessions or matches, quantified in either external (e.g., duration, distance covered) or internal load (e.g., heart rate [HR]), to obtain a training outcome over time. A total of 6492 records were retrieved, of which 3304 were duplicates. After screening the titles, abstracts and full texts, we identified 12 full-text articles that matched our inclusion criteria. One of these articles was identified through additional sources. All of these articles used correlations to examine the relationship between load indicators and training outcomes. For pre-season, training time spent at high intensity (i.e., >90 % of maximal HR) was linked to positive changes in aerobic fitness. Exposure time in terms of accumulated training, match or combined training, and match time showed both positive and negative relationships with changes in fitness over a season. Muscular perceived exertion may indicate negative changes in physical fitness. Additionally, it appeared that training at high intensity may involve a higher injury risk. Detailed external load indicators, using electronic performance and tracking systems, are relatively unexamined. In addition, most research focused on the relationship between training load indicators and changes in physical fitness, but less on injury and illness. HR indicators showed relationships
Clemente, Filipe Manuel; Mendes, Bruno; Nikolaidis, Pantelis Theodoros; Calvete, Francisco; Carriço, Sandro; Owen, Adam Lee
Monitoring internal training load has been extensively used and described within team sport environments, however when compared to internal physiological measures such as heart rate (HR) and rating of perceived exertion (RPE), the literature is sparse. The primary aim of this investigation study was to assess differences of playing position on ITL, session-RPE and wellness across two different training microcycles (1 vs. 2 competitive games), in addition with examining the relationship between ITL and Hooper's Index across an entire season. Thirty-five professional soccer players from the Portuguese premier league participated in the study (25.7±5.0years; 182.3±6.4cm; 79.1±7.0kg). Analysis of variance revealed higher values of DOMS (Means(M): 3.33 vs. 3.10; p=0.001; effect Size (ES)=0.087), fatigue (M: 3.18 vs. 2.99; p=0.001; ES=0.060) and HI (M: 11.85 vs. 11.56; p=0.045; ES=0.034) in 2-game weeks compared with 1-game weeks. Correlation between ITL and HI levels found significant negative correlations between ITL and DOMS (ρ=-0.156), ITL and sleep (ρ=-0.109), ITL and fatigue (ρ=-0.225), ITL and stress (ρ=-0.188), and ITL and HI (ρ=-0.238) in 2-game weeks. Results from 1-game microcycle only highlighted negative correlations between ITL and stress (ρ=-0.080). It was concluded from the study that greater fatigue potential, muscle soreness, stress and ITL was significantly more apparent within a 2-game microcycle. As a result, care should be taken when planning the lead into and out of a 2-game fixture microcycle highlighting key specific recovery strategies to damped the increased stress effect. Additionally, the potential utilization of squad rotation strategies may be a positive approach with aim of managing the fatigue effect. Copyright © 2017 Elsevier Inc. All rights reserved.
Read, Paul J; Oliver, Jon L; Myer, Gregory D; De Ste Croix, Mark B A; Lloyd, Rhodri S
Asymmetry is a risk factor for male youth soccer players. There is a paucity of data confirming the presence of asymmetry using practically viable screening tasks in players at different stages of maturation. A cross sectional sample (N = 347) of elite male youth soccer players who were either (pre-, circa- or post-peak height velocity (PHV)) completed the following single leg assessments: Y-Balance anterior reach (Y-Bal); hop for distance (SLHD); 75% hop and stick (75%Hop) and countermovement jumps (SLCMJ). SLCMJ landing force asymmetry was higher in both circa and post-PHV groups, (p < 0.001; d = 0.41 - 0.43). 75%Hop landing force asymmetries were also highest in circa PHV players but between group comparisons were not statistically significant and effect sizes were small. SLHD and Y-Bal asymmetries reduced with maturation; however, no group differences were significant, with small to trivial effect sizes (d = ≤ 0.25). Stage of maturation did not have a profound effect on asymmetry. Between-limb differences in functional performance seem to be established in early childhood; thus, targeted interventions to reduce this injury risk factor should commence in pre-PHV athletes and be maintained throughout childhood and adolescence to ensure asymmetry does not increase.
Chmura, Paweł; Andrzejewski, Marcin; Konefał, Marek; Mroczek, Dariusz; Rokita, Andrzej; Chmura, Jan
The aim of the present study was to analyze motor activities of soccer players in seven consecutive rounds of matches of the 2014 World Cup in Brazil and to compare the performance of the world champions, the German national team with other participating teams. The study sample comprised 905 observations of 340 soccer players, who played full-time matches in all seven rounds of the tournament. The study was conducted using data collected from the Castrol Performance Index, a kinematic game analysis system that records movements of players with semi-automatic cameras. The following variables were analyzed: total distance covered, the percentage of total distance covered at high intensity, the number of sprints, frequency of sprints and peak running speed. A statistically significant increase (p ≤ 0.01) was noted in total distance covered, the percentage of distance covered at high intensity and total number of sprints, between the quarter-finals and semi-finals of the World Cup tournament in Brazil. The German national team covered a significantly longer total distance (p ≤ 0.05) and had a greater percentage of distance covered at high intensity (p ≤ 0.001) than players from other teams. The obtained results point to the necessity of development of players' aerobic endurance and speed-endurance abilities while preparing for top-level soccer tournaments. Winning a soccer championship requires players to run longer mean total distances and longer distances at high intensity during a single match.
Saeed Najafpour Bushehry
Full Text Available Exercise and nutrition have a significant impact on health. To evaluate nutrient consumption pattern of soccer players in city of Shiraz, 323 players were selected by proportional multi-stage cluster random sampling from 11 clubs in Shiraz. Anthropometric indices, socioeconomic status, 24 hours dietary recall and food frequency data were collected. Protein, carbohydrate and fat intake of the players were 73.73 gr (10.8%, 493.3 gr (72.4% and 50.8 gr (16.7%, respectively. Calcium (689.6 mg, phosphorus (734.4 mg, iron (20.3 mg, vitamin B1 (2 mg, vitamin B2 (1.6 mg, vitamin C (107.5 mg and vitamin A (962.4 mcg RE intake were lower than the desirable levels. The mean energy consumption of the players was 2723 Kcal per day. In conclusion, protein and micronutrients intakes are not desirable in Iranian soccer players in Shiraz.
Zebis, Mette K; Andersen, Lars L; Ellingsgaard, Helga; Aagaard, Per
Knee joint injuries are a serious issue in soccer. The ability to protect the knee from injury depends largely on the strength of the hamstring relatively to the quadriceps, that is, a low hamstring/quadriceps (H/Q) strength ratio is suggested as a risk factor. Although maximal muscle strength (MVC) has often been used to evaluate the H/Q ratio, the ability to rapidly develop force (rate of force development [RFD]) is more relevant in relation to fast dynamic movements. The aim of this study was to introduce and investigate a rapid RFD H/Q strength ratio compared with the traditional MVC H/Q strength ratio in elite soccer players. Twenty-three elite soccer players (11 women, 12 men) performed maximal voluntary static contraction for the hamstring and quadriceps in an isokinetic dynamometer, from which the maximal muscles strength (MVC) and RFD were extracted. Test-retest reliability for the RFD H/Q ratio was high (intraclass correlation coefficient = 0.664-0.933). The initial contraction phase up to 50 milliseconds from the onset of contraction showed a low RFD H/Q ratio compared to the MVC H/Q ratio (p MVC H/Q ratio, compared with the group mean-sustained ACL rupture at a later occasion. The high reliability of the new RFD H/Q strength ratio indicates that the method is a relevant tool in standardized clinical evaluation of the knee joint agonist-antagonist relationship.
Barbosa, Carlos V. da Silva; Silva, Alexandre S.; de Oliveira, Caio V. C.; Massa, Nayara M. L.; de Sousa, Yasmim R. F.; da Costa, Whyara K. A.; Silva, Ayice C.; Delatorre, Plínio; Carvalho, Rhayane; Braga, Valdir de Andrade; Magnani, Marciane
Nutritional intervention with antioxidants rich foods has been considered a strategy to minimize the effects of overtraining in athletes. This experimental, randomized, and placebo-controlled study evaluated the effects of consumption of sesame (Sesamum indicum L.) on muscle damage markers, oxidative stress, systemic inflammation, and aerobic performance in male semi-professional soccer players. Twenty athletes were randomly assigned to groups that received 40 g (two tablespoons) per day of sesame or a placebo during 28 days of regular training (exposed to routine training that includes loads of heavy training in the final half of the season). Before and after intervention, creatine kinase (CK), lactate dehydrogenase (LDH), malondialdehyde (MDA), superoxide dismutase (SOD), C-reactive protein (hs-CRP), and aerobic capacity were evaluated. Before intervention, a physiologic imbalance was noted in both groups related to CK and LDH levels. Sesame intake caused a reduction of CK (19%, p < 0.05), LDH (37%, p < 0.05), MDA (55%, p < 0.05) and hs-CRP (53%, p < 0.05) and increased SOD (14%, p < 0.05), vitamin A (25%, p < 0.05), and vitamin E (65%, p < 0.05) in the experimental group. These phenomena were accompanied by increased aerobic capacity (17%, p < 0.05). The placebo group showed an increase in CK (5%, p < 0.05) and no significant change in LDH, SOD or vitamin A. MDA levels decreased (21%, p < 0.05) and vitamin E increased (14%, p < 0.05) in the placebo group, but to a much lesser extent than in the experimental group. These results show that sesame consumption may reduce muscle damage and oxidative stress while improving the aerobic capacity in soccer players. PMID:28408889
Full Text Available The aim of this investigation was to assess whether the demands of the modern English competitive soccer season would be reflected in the mood states of professional soccer players. Sixty-nine male participants either activity competing in English soccer leagues or resident in England were recruited and grouped accordingly as professional soccer players, university level soccer players, Sunday league soccer players, or non-sporting controls. On three separate occasions; at the beginning, at the middle, and finally towards the end of the English soccer season, participants completed both the Profile of Mood States (POMS questionnaire as well as a questionnaire related to their teams’ performance in addition to their perceived life stress. Results showed the POMS scores to differ over the season in relation to the groups’ standard of competition. ANOVAs demonstrated this pattern to be significant for the dependent measures of tension, depression, and confusion with significant group by time interactions (95% level of confidence. At the outset of the season professionals had the most positive POMS profile, however, as the season progressed they showed the greatest change towards a negative profile. These results indicate that English soccer is placing professional players at a predisposition of demonstrating POMS commensurate with negative adaptation to training, having important implications for their long-term performance and health.
Bailey, Daniel; Firth, Paul
To determine whether the bilateral application of kinesiology tape (KT) to professional footballers' ankles can improve their lower limb proprioception. A single blind randomised crossover study. Participants were randomly assigned to complete a proprioception test in either a taped or not taped condition first. Following a wash out period, participants were then re-tested in the alternate condition. A UK Championship League Football Club, mid-season. Twenty male professional football players over the age of 18, currently match fit with no injuries. Proprioception was assessed by participants undertaking the moving target program on the balance module attached to a Kin-Com 125AP isokinetic dynamometer. A paired sample two tailed t-test was used to assess whether there was a significant difference between the participants test scores in the not taped and taped conditions. The bilateral application of KT to professional footballers' ankles did not bring about a significant change in participants' scores when tested with a fine movement and balance control test. Percentage accuracy score mean difference 4.2 (p = 0.285). The results of this study do not support the use of KT when applied to the ankles of healthy footballers as a method of improving proprioception. Copyright © 2016 Elsevier Ltd. All rights reserved.
Lara A. Thompson
Full Text Available Static balance has a relevant influence on athletic performance as well as on reducing the risk of injury. The main goal of this study was to assess soccer athlete versus non-athlete balance performance via displacement and velocity parameters extracted from the center-of-pressure (COP position time series. In order to accomplish our goal, we investigated standing balance in two male groups with unimpaired balance: non-athletes (n = 12 and collegiate varsity soccer athletes (n = 12. In order to make the standing balancing task more or less difficult, we altered participant base-of-support, as well as vision, yielding static (quiet stance test conditions increasing in difficulty. From the COP position time series, displacement and velocity parameters were computed and plotted as a function of increasing test condition difficulty level. COP parameters showed steeper increases with increased test difficulty in non-athletes compared to athletes; this demonstrated athletes’ better ability to control their balance. We concluded that balance performance could be characterized via COP displacement and velocity response curves. This study lends new insights into how COP parameters can be utilized to determine and characterize improvements in balance between un-impaired subject populations (athletes versus non-athletes.
Giménez, Jesús V; Del-Coso, Juan; Leicht, Anthony S; Gomez, Miguel A
The purpose of this investigation was to compare the movement patterns of professional soccer players during a small-sided game (SSG), a large-sided game (LSG) and a competitive friendly match (FM). Fourteen professional players participated in three training routines with a similar relative pitch area per player. The SSG and LSG consisted of 8 repetitions of 4-min game play, interspersed by 2-min of active recovery, and their data were compared to the first 32 minutes of a FM. All movement patterns from walking to sprint running were recorded using 10Hz GPS devices while player perception of exertion was recorded via visual analogue scale, post-trial. Total running distance (3852±405 vs. 3359±429 and 3088 ± 414 m), running distance at 5-6.9 m/s (222±98 vs. 75±53 and 49±35 m) and maximal running speed (7.0±0.7 vs. 6.1±0.4 and 6.0±0.7 m/s) were significantly greater during FM than for SSG and LSG. However, the number of accelerations (462±16 vs. 458±12 vs. 422±15) and decelerations (733±31 vs. 692 ±24 vs. 609±27), and the rating of perceived exertion (8±1 vs. 7±1 vs. 5±1) were significantly greater during SSG compared to LSG and FM. Although smaller game-based training routines do not replicate exactly the movement patterns of a competitive match, they can increase the execution of short-term and high-intensity movements for specialised training in professional soccer players.
Cazzola, R; Russo-Volpe, S; Cervato, G; Cestaro, B
Physical exercise is characterized by an increase in oxygen consumption by the whole body. This leads to a decrease in antioxidant levels that could promote both an increase in the markers of lipoprotein peroxidation and damage to the erythrocyte membrane with consequent modification of membrane fluidity. Different markers of oxidative stress, erythrocyte membrane fluidity and antioxidant status were determined in 20 professional soccer players and 20 sedentary controls. Plasma lipoperoxides and kinetics of Cu-stimulated plasma peroxidation were measured together with hydrosoluble (albumin, uric acid and vitamin C), liposoluble (vitamin E and bilirubin) and enzymatic (superoxide dismutase and glutathione peroxidase) serum antioxidants. Erythrocyte membrane rigidity was determined by measuring fluorescence anisotropy (rs) of the fluorescent probe 1, 3, 5 diphenylexatriene. The sportsmen showed higher levels of the following plasmatic antioxidants: ascorbic acid (Pmembrane fluidity (P=0.0152) were found to be significantly higher in the soccer players. Athletes undergoing regular and adequate training show improved antioxidant status together with a more fluid membrane status, which could contribute to improving both peripheral resistance to insulin and all the functional metabolic interchanges in the cellular membrane.
Requena, Bernardo; García, Inmaculada; Suárez-Arrones, Luis; Sáez de Villarreal, Eduardo; Naranjo Orellana, José; Santalla, Alfredo
Requena, B, García, I, Suárez-Arrones, L, Sáez de Villarreal, E, Naranjo Orellana, J, and Santalla, A. Off-season effects on functional performance, body composition, and blood parameters in top-level professional soccer players. J Strength Cond Res 31(4): 939-946, 2017-To examine the effects of a standard off-season period (OSP) on aerobic, sprint, and jumping performances, and body and blood composition in a top-level soccer team. Nineteen soccer players were measured. The OSP included to 2 weeks of no training (resting phase) and a 4-week period of moderate-training load (phase in which each player performed the vacation exercise plan). Player's functional performance (15- and 30-m sprint times [seconds], vertical jump [meter], and incremental field test Vam-Eval [kilometer per hour]), percentage of body fat (%) and blood composition (hematological and biochemical data) were measured at mid-season, end-season, and after the OSP. The percentage of body fat was nonaltered during the competitive season (10.8 ± 3.6 and 10.5 ± 3.5%) and increased significantly after the OSP (11.6 ± 3.6%, p ≤ 0.05). Similarly, the maximal aerobic speed (VVam-Eval) velocity (kilometer per hour) decreased (p ≤ 0.05) from 17.4 ± 1 and 17.3 ± 1.2 during the competitive season to 16.6 ± 0.9 after the OSP. The hematocrit and blood hemoglobin concentration increased (p ≤ 0.05) during the OSP, showing a blood hemoconcentration adaptation. However, sprint time (seconds) and jump height (meters) showed no significant changes after the OSP. Soccer players maintained their functional performance during high-intensity activities such as jumping or sprinting after the OSP proposed. By contrast, there was a decrease in aerobic performance (VVam-Eval) accompanied by a blood hemoconcentration, and an increase of body fat mass associated with a reduction of fat-free mass of the lower limbs. Our data suggest that an end-season evaluation is needed to design holiday training programs
Lynall, Robert C; Clark, Michael D; Grand, Erin E; Stucker, Jaclyn C; Littleton, Ashley C; Aguilar, Alain J; Petschauer, Meredith A; Teel, Elizabeth F; Mihalik, Jason P
There are limited nonlaboratory soccer head impact biomechanics data. This is surprising given soccer's global popularity. Epidemiological data suggest that female college soccer players are at a greater concussion injury risk than their male counterparts. Therefore, the purposes of our study were to quantify head impact frequency and magnitude during women's soccer practices and games in the National Collegiate Athletic Association and to characterize these data across event type, playing position, year on the team, and segment of game (first and second halves). Head impact biomechanics were collected from female college soccer players (n = 22; mean ± SD age = 19.1 ± 0.1 yr, height = 168.0 ± 3.5 cm, mass = 63.7 ± 6.0 kg). We employed a helmetless head impact measurement device (X2 Biosystems xPatch) before each competition and practice across a single season. Peak linear and rotational accelerations were categorized based on impact magnitude and subsequently analyzed using appropriate nonparametric analyses. Overall, women's college soccer players experience approximately seven impacts per 90 min of game play. The overwhelming majority (~90%) of all head impacts were categorized into our mildest linear acceleration impact classification (10g-20g). Interestingly, a higher percentage of practice impacts in the 20g-40g range compared with games (11% vs 7%) was observed. Head impact biomechanics studies have provided valuable insights into understanding collision sports and for informing evidence-based rule and policy changes. These have included changing the football kickoff, ice hockey body checking ages, and head-to-head hits in both sports. Given soccer's global popularity, and the growing public concern for the potential long-term neurological implications of collision and contact sports, studying soccer has the potential to impact many athletes and the sports medicine professionals caring for them.
Saeed Najafpour Bushehry; Shahnaz Ravanshad; Bahram Zeghami; Esfandyar Sotudeh Maram
Exercise and nutrition have a significant impact on health. To evaluate nutrient consumption pattern of soccer players in city of Shiraz, 323 players were selected by proportional multi-stage cluster random sampling from 11 clubs in Shiraz. Anthropometric indices, socioeconomic status, 24 hours dietary recall and food frequency data were collected. Protein, carbohydrate and fat intake of the players were 73.73 gr (10.8%), 493.3 gr (72.4%) and 50.8 gr (16.7%), respectively. Calcium (689.6 mg...
Ranchordas, Mayur K; Tiller, Nicholas B; Ramchandani, Girish; Jutley, Raj; Blow, Andrew; Tye, Jonny; Drury, Ben
The purpose of this paper was to report normative data on regional sweat sweat-sodium concentrations of various professional male team-sport athletes, and to compare sweat-sodium concentrations among sports. Data to this effect would inform our understanding of athlete sodium requirements, thus allowing for the individualisation of sodium replacement strategies. Accordingly, data from 696 athletes (Soccer, n = 270; Rugby, n = 181; Baseball, n = 133; American Football, n = 60; Basketball, n = 52) were compiled for a retrospective analysis. Regional sweat-sodium concentrations were collected using the pilocarpine iontophoresis method, and compared to self-reported measures collected via questionnaire. Sweat-sodium concentrations were significantly higher (p sports. There were strong positive correlations between sweat-sodium concentrations and self-reported sodium losses in American football (rs = 0.962, p sports science/medicine practitioners in generating bespoke hydration and electrolyte-replacement strategies to meet the sodium demands of professional team-sport athletes. Moreover, these novel data suggest that self-reported measures of sodium loss might serve as an effective surrogate in the absence of direct measures; i.e., those which are more expensive or non-readily available.
Renan Felipe Hartmann Nunes
Full Text Available Muitos profissionais do esporte periodizam o treinamento do futebol e do futsal de forma semelhante. Todavia, pouco se conhece das respostas físicas e fisiológicas dos atletas de futsal. Esse estudo comparou perfil antropométrico, capacidade aeróbia e produção de potência entre atletas profissionais de futsal e futebol. Onze jogadores de futsal (idade 24,1±2,4anos e 21 jogadores de futebol (idade 22,6±3,6anos do sexo masculino submeteram-se a duas sessões experimentais: (I avaliação antropométrica, teste de esforço máximo em esteira e (II teste de velocidade de 30 metros (capacidade de sprint repetido, CSR. Empregou-se teste t para amostras independentes, permitindo verificar possíveis diferenças entre as modalidades (pMany professional sports training periodize soccer and futsal similarly. However, little is known about physical and physiological responses of futsal players. This study compared anthropometric, aerobic capacity and power production among professional indoor and outdoor soccer players. Eleven futsal players (age 24.1±2.4 years and 21 soccer players (age 22.6±3.6 years males underwent two experimental sessions: (i anthropometric measurements, maximal effort test treadmill and (II test speed of 30 meters (repeated sprint ability, CSA. It was applied t-test for independent samples to verify possible differences between the modalities (p>0,05. The futsal players showed higher values of HR VT (177,2±10 e 67,1±10,8 bpm VO2max ;VO2VT; %VO2max (62,5±4,3 e 52,1±4,6; 58,7±5,6 e 43,1±4,6; 76±8,4 e 93,9±5,3 ml·kg-1·min-1 compared with soccer players, respectively. These results demonstrate the need for specific methods of training for outdoor and indoor soccer.
M. Magalhães Sales
Conclusion: The anthropometric profile of soccer players that act in the United Arab Emirates is similar to others around the world. However, regarding the physical fitness, results are still inconclusive, since findings from other studies suggest that the anaerobic power of our sample is alike or lower than other elite players throughout the world. Likewise indirect VO2max, especially given the acknowledged limitations of obtaining indirectly this variable. In addition, making an analysis by playing position, the results of this study are similar to previous research.
van Gemert, J.C.; Schavemaker, J.G.M.; Bonenkamp, K.; Spink, A.J.; Loijens, L.W.S.; Woloszynowska-Fraser, M.; Noldus, L.P.J.J.
Amateur soccer statistics have interesting applications such as providing insights to improve team performance, individual coaching, monitoring team progress and personal or team entertainment. Professional soccer statistics are extracted with labor intensive expensive manual effort which is not
Idoate, Fernando; Calbet, Jose A. L.; Izquierdo, Mikel; Sanchis-Moysi, Joaquin
Purpose To determine the volume and degree of asymmetry of the rectus abdominis muscle (RA) in professional soccer players. Methods The volume of the RA was determined using magnetic resonance imaging (MRI) in 15 professional male soccer players and 6 non-active male control subjects. Results Soccer players had 26% greater RA volume than controls (Psoccer players (P = 0.42) and in controls (P = 0.75) (Dominant/non-dominant = 0.99, in both groups). Segmental analysis showed a progressive increase in the degree of side-to-side asymmetry from the first lumbar disc to the pubic symphysis in soccer players (r = 0.80, Psoccer players, although this trend was not statistically significant (P = 0.14). Conclusions Professional soccer is associated with marked hypertrophy of the rectus abdominis muscle, which achieves a volume that is 26% greater than in non-active controls. Soccer induces the hypertrophy of the non-dominant side in proximal regions and the dominant side in regions closer to pubic symphysis, which attenuates the pattern of asymmetry of rectus abdominis observed in non-active population. It remains to be determined whether the hypertrophy of rectus abdominis in soccer players modifies the risk of injury. PMID:21541351
Silvers-Granelli, Holly J; Bizzini, Mario; Arundale, Amelia; Mandelbaum, Bert R; Snyder-Mackler, Lynn
The FIFA 11+ injury prevention program has been shown to decrease the risk of soccer injuries in men and women. The program has also been shown to decrease time loss resulting from injury. However, previous studies have not specifically investigated how the program might impact the rate of anterior cruciate ligament (ACL) injury in male soccer players. The purpose of this study was to examine if the FIFA 11+ injury prevention program can (1) reduce the overall number of ACL injuries in men who play competitive college soccer and whether any potential reduction in rate of ACL injuries differed based on (2) game versus practice setting; (3) player position; (4) level of play (Division I or II); or (5) field type. This study was a prospective cluster randomized controlled trial, which was conducted in 61 Division I and Division II National Collegiate Athletic Association men's soccer teams over the course of one competitive soccer season. The FIFA 11+ is a 15- to 20-minute on-the-field dynamic warm-up program used before training and games and was utilized as the intervention throughout the entire competitive season. Sixty-five teams were randomized: 34 to the control group (850 players) and 31 to the intervention group (675 players). Four intervention teams did not complete the study and did not submit their data, noting insufficient time to complete the program, reducing the number for per-protocol analysis to 61. Compliance to the FIFA 11+ program, athletic exposures, specific injuries, ACL injuries, and time loss resulting from injury were collected and recorded using a secure Internet-based system. At the end of the season, the data in the injury surveillance system were crosshatched with each individual institution's internal database. At that time, the certified athletic trainer signed off on the injury collection data to confirm their accuracy and completeness. A lower proportion of athletes in the intervention group experienced knee injuries (25% [34 of
Wells, C M; Edwards, A M; Winter, E M; Fysh, M L; Drust, B
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 (P<0.05). However, neither tests 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.
Daniel Barbosa Coelho
Full Text Available Serum creatine kinase (CK concentration has been widely used as an indicator of skeletal muscle damage in sports. However, there are no longitunal studies on post-game CK kinetics in Soccer during a competitive season. The aim of this study was to evaluate serum CK kinetics in professional Soccer players at different post-game times during a competitive season without training interruption. Seventeen professional soccer players (age: 22.2±3.1 years, height: 179±6.0 cm, body fat percentage: 9.5±1.1, and 67.0±3.5 mL O2/kg/min were evaluated over a period of 3 months of the national championship. Serum CK concentration was measured before the beginning of the season (baseline and at four different times after a soccer game (post-1: 12-20 h, post-2: 36-48 h, post-3: 60-65 h, and post-4: 90-110 h. Plasma CK concentrations were higher at all times when compared to baseline (p<0.05. Post-2 CK concentration was lower than post-1 and higher than post-3 and -4 (p<0.05, with no significant differences between post-3 and post-4. In conclusion, serum CK kinetics was influenced by the training routine of the soccer players, with a peak between 12 and 20 h after the game, returning to normal within 60-65 h. This procedure can be used to monitor the recovery state of athletes and game and training intensities.
Daniel Barbosa Coelho
Full Text Available Serum creatine kinase (CK concentration has been widely used as an indicator of skeletal muscle damage in sports. However, there are no longitunal studies on post-game CK kinetics in Soccer during a competitive season. The aim of this study was to evaluate serum CK kinetics in professional Soccer players at different post-game times during a competitive season without training interruption. Seventeen professional soccer players (age: 22.2±3.1 years, height: 179±6.0 cm, body fat percentage: 9.5±1.1, and 67.0±3.5 mL O2/kg/min were evaluated over a period of 3 months of the national championship. Serum CK concentration was measured before the beginning of the season (baseline and at four different times after a soccer game (post-1: 12-20 h, post-2: 36-48 h, post-3: 60-65 h, and post-4: 90-110 h. Plasma CK concentrations were higher at all times when compared to baseline (p<0.05. Post-2 CK concentration was lower than post-1 and higher than post-3 and -4 (p<0.05, with no significant differences between post-3 and post-4. In conclusion, serum CK kinetics was influenced by the training routine of the soccer players, with a peak between 12 and 20 h after the game, returning to normal within 60-65 h. This procedure can be used to monitor the recovery state of athletes and game and training intensities.
Owen, Adam L; Forsyth, Jacky J; Wong, Del P; Dellal, Alexandre; Connelly, Sean P; Chamari, Karim
Elite-level professional soccer players are suggested to have increased physical, technical, tactical, and psychological capabilities when compared with their subelite counterparts. Ensuring these players remain at the elite level generally involves training many different bodily systems to a high intensity or level within a short duration. This study aimed to examine whether an increase in training volume at high-intensity levels was related to injury incidence, or increased the odds of sustaining an injury. Training intensity was monitored through time spent in high-intensity (T-HI) and very high-intensity (T-VHI) zones of 85-training volume at T-HI and injury incidence (r = 0.57, p = 0.005). Further analysis revealed how players achieving more time in the T-VHI zone during training increased the odds of sustaining a match injury (odds ratio = 1.87; 95% CI, 1.12-3.12, p = 0.02) but did not increase the odds of sustaining a training injury. Reducing the number of competitive match injuries among elite-level professional players may be possible if greater focus is placed on the training intensity and volume over a period of time ensuring the potential reduction of fatigue or overuse injuries. In addition, it is important to understand the optimal training load at which adaptation occurs without raising the risk of injury.
Owen, Adam L; Forsyth, Jacky J; Wong, Del P; Dellal, Alexandre; Connelly, Sean; Chamari, Karim
Elite level professional soccer players are suggested to have increased physical, technical, tactical and psychological capabilities when compared to their sub-elite counterparts. Ensuring these players remain at the elite level generally involves training many different bodily systems to a high intensity or level within a short duration. This study aimed to examine whether an increase in training volume at high intensity levels were related to injury incidence, or increased the odds of sustaining an injury. Training intensity was monitored through time spent in high- (T-HI) and very high- (T-VHI) intensity zones of 85-training volume at T-HI and injury incidence (r=0.57, p=0.005). Further analysis revealed how players achieving more time in the T-VHI zone during training increased the odds of sustaining a match injury (odds ratio=1.87, 95% CI 1.12 to 3.12, p=0.02), but did not increase the odds of sustaining a training injury. Reducing the number of competitive match injuries amongst elite professional level players may be possible if greater focus is placed on the training intensity and volume over a period of time ensuring the potential reduction of fatigue or overuse injuries. In addition, it is important to understand the optimal training load at which adaptation occurs without raising the risk of injury.
García García, Oscar; Rial Boubeta, Antonio; Real Deus, Eulogio
The goal of this article is to detect, describe, and compare 2 heart rate (HR) conditions associated with high-intensity efforts but somewhat different in nature: The first one is indicated by HR values close to the maximum heart reserve (MHRR), and the second is indicated by a marked increase in the HR values (MIHR). It was expected that both conditions were associated with different game situations. A sample of 441 game situations (241 MIHRs and 200 MHRRs), taken from HR records and individual filming of 12 elite soccer players, was assessed along 7 preseason competition matches. The game situations in which each of these 441 HR conditions took place were identified, using a previously established taxonomy of a combination of field formats and category systems in the Match Vision Studio Premium. For the recording of the HR condition, an HRM Polar was attached to the players when in competition, together with a simultaneous filming of their performance during the game. The HRM and video recordings were synchronized beforehand to be able to relate the game situation in the film with HR conditions. The results showed significant differences between both HR conditions for 4 criteria of game situations (Ball in play, Game Center, Role, and Opposition). In all the cases, the MIHR is more associated with active participation of the players in the game, whereas the MHRR is more associated with the end of this participation. Thus, the results suggest that MIHR could be a useful complementary measurement to assess the intensity of physiological load that elite soccer players bear during competition, together with more traditional measurements such as MHRR.
Gatterer, H; Ruedl, G; Faulhaber, M; Regele, M; Burtscher, M
Soccer is characterized by high injury rates that necessitate interventions for its reduction. The "11" is a multi-modal preventive program that was developed to reduce injury rate. However, outcomes on the effectiveness of the program are not unambiguous and data for the largest group at risk (i.e., male adult amateur players) are missing. The study aims to assess the injury rate in male adult amateur soccer players of different levels and to evaluate the effectiveness of the prevention program the "11". Three amateur soccer teams participated in the study during the first round of a competition season. Two teams played at a regional level (6th Italian league) and one team at a provincial level (7th Italian league). The regional league is of a higher skill level compared to the provincial league. Duration and frequency of training and match sessions and the occurrence of time-loss injuries were recorded. One team of the 6th league performed an injury prevention program. The total injury rate for the intervention and the control team in the 6th league was 3.3 (CI 0.7-5.9) and 4.3 (CI 1.3-7.3) injuries/1000 h, respectively (P=0.841). The 6th league control team tended to have a lesser injury rate compared to the 7th league team (P=0.081). The relative risk was 2 fold higher in the 7th compared to the 6th league team (P=0.0285 one tailed). Present results show that injury rate in amateur soccer depended rather on the skill level than the prevention program. In this study the prevention program the "11" was not shown to be highly effective in soccer player of intermediate level (i.e., 6th Italian league).
Ostojic, Sergej M; Sanja Mazic
The aim of this study was to examine the effects of a carbohydrate-electrolyte drink on specific soccer tests and performance. Twenty-two professional male soccer players volunteered to participate in the study. The players were allocated to two assigned trials ingesting carbohydrate-electrolyte drink (7% carbohydrates, sodium 24 mmol.l-1, chloride 12 mmol.l-1, potassium 3 mmol.l-1) or placebo during a 90 min on-field soccer match. The trials were matched for subjects’ age, weight, height and...
Akbulut, Taner; Agopyan, Ani
The aim of this study was to determine the effect of the 8-week proprioceptive neuromuscular facilitation (PNF) exercises that were carried out on lower extremity on kicking speed and range of motion (ROM) performance in young soccer players. Twenty-four soccer players (15.6 ± 0.4 years) were selected from nonprofessional young soccer team. All players' height, weight, ROM (ankle plantar and dorsal flexions, hip flexions and extensions), and kicking speed tests were evaluated before and after 8 weeks. The participants were divided into PNF (n = 11) and control (n = 11) groups. Both groups continued technical and tactical soccer training together 3 days (120 min·d) a week. The PNF group attended additionally unassisted PNF-contract-relax (CR) stretching through 8 weeks, 2 days per week, 20 minutes' session duration. The control group did not participate in any additional PNF stretching sessions. There were significant differences in kicking speed, right ankle active dorsal flexion, and hip active flexion (right and left) (p ≤ 0.05) of the PNF group, whereas there were no significant differences between groups in left ankle active dorsal flexion, hip active extension (right and left), and ankle active plantar flexion (right and left) (p > 0.05). We conclude that an 8-week unassisted PNF-CR improved on the ROM of particular lower extremity joints and the kicking speed in the young male soccer players. These results provide strength and conditioning coaches with a practical way to use unassisted PNF-CR in warm-up for positive improvements in the ROM of the hip and ankle and the applications of the kicking speed.
Eleftherios Kellis, Nikiforos Galanis, Chrysanthos Chrysanthou, Nikolaos Kofotolis
Full Text Available This study examined the use of ultrasound to monitor changes in the long head of the biceps femoris (BF architecture of aprofessional soccer player with acute first-time hamstring strain. The player followed a 14 session physiotherapy treatment until return to sport. The pennation angle and aponeurosis strain of the long head of the biceps femoris (BF were monitored at 6 occasions (up until 1 year after injury. The size of the scar / hematoma was reduced by 63.56% (length and 67.9% (width after the intervention and it was almost non-traceable one year after injury. The pennation angle of the fascicles underneath the scar showed a decline of 51.4% at the end of the intervention while an increase of 109.2% of the fascicles which were closer to deep aponeurosis was observed. In contrast, pennation angle of fascicles located away from the injury site were relatively unaffected. The treatment intervention resulted in a 57.9% to 77.3% decline of maximum strain per unit of MVC moment and remained similar one year after the intervention. This study provided an example of the potential use of ultrasound-based parameters to link the mechanical adaptations of the injured muscle to specific therapeutic intervention.
Valente-dos-Santos, João; Coelho-e-Silva, Manuel J; Simões, Filipe; Figueiredo, Antonio J; Leite, Neiva; Elferink-Gemser, Marije T; Malina, Robert M; Sherar, Lauren
This study evaluates the contributions of age, growth, skeletal maturation, playing position and training to longitudinal changes in functional and skill performance in male youth soccer. Players were annually followed over 5 years (n = 83, 4.4 measurements per player). Composite scores for functional and skill domains were calculated to provide an overall estimate of performance. Players were also classified by maturity status and playing position at baseline. After testing for multicollinearity, two-level multilevel (longitudinal) regression models were obtained for functional and skill composite scores. The scores improved with age and training. Body mass was an additional predictor in both models [functional (late maturing): 13.48 + 1.05 × centered on chronological age (CA)-0.01 × centered CA(2)-0.19 × fat mass (FM) + 0.004 × annual volume training-1.04 × dribbling speed; skills (defenders): 7.62 + 0.62 × centered CA-0.06 × centered CA(2) + 0.04 × fat-free mass-0.03 x FM + 0.005 × annual volume training-0.19 × repeated-sprint ability + 0.02 × aerobic endurance]. Skeletal maturity status was a significant predictor of functional capacities and playing position of skill performance. Sound accuracy of each multilevel model was demonstrated on an independent cross-sectional sample (n = 52).
Abt, Grant; Lovell, Ric
As with other match analysis systems, ProZone uses an absolute speed threshold to identify running speeds at "high-intensity". In this study, we examined the use of an individualized high-intensity speed threshold based on the speed at the second ventilatory threshold (VT(2speed)) for assessment of the distance run at high-intensity during matches. Ten professional soccer players completed a maximal treadmill test to determine VT(2speed). Match data were identified by means of the ProZone match analysis system. The distances run at high-intensity during matches were calculated using the default value (19.8 km . h(-1)) and VT(2speed). Differences between VT(2speed) and the default were analysed using a non-parametric median sign test. The distances run at high-intensity were compared with a paired t-test. The median VT(2speed) was 15 km x h(-1) (range 14-16 km x h(-1)), which was less than the default (P distance run at high-intensity based on the default and VT(2speed) was 845 m (s = 296) and 2258 m (s = 707), respectively [mean difference 1413 m; P distance run at high-intensity can be substantially underestimated.
Rowsell, Greg J; Coutts, Aaron J; Reaburn, Peter; Hill-Haas, Stephen
In this study, we investigated the effect of water immersion on physical test performance and perception of fatigue/recovery during a 4-day simulated soccer tournament. Twenty high-performance junior male soccer players (age 15.9 +/- 0.6 years) played four matches in 4 days and undertook either cold-water immersion (10 +/- 0.5 degrees C) or thermoneutral water immersion (34 +/- 0.5 degrees C) after each match. Physical performance tests (countermovement jump height, heart rate, and rating of perceived exertion after a standard 5-min run and 12 x 20-m repeated sprint test), intracellular proteins, and inflammatory markers were recorded approximately 90 min before each match and 22 h after the final match. Perceptual measures of recovery (physical, mental, leg soreness, and general fatigue) were recorded 22 h after each match. There were non-significant reductions in countermovement jump height (1.7-7.3%, P = 0.74, eta(2) = 0.34) and repeated sprint ability (1.0-2.1%, P = 0.41, eta(2) = 0.07) over the 4-day tournament with no differences between groups. Post-shuttle run rating of perceived exertion increased over the tournament in both groups (P < 0.001, eta(2) = 0.48), whereas the perceptions of leg soreness (P = 0.004, eta(2) = 0.30) and general fatigue (P = 0.007, eta(2) = 0.12) were lower in the cold-water immersion group than the thermoneutral immersion group over the tournament. Creatine kinase (P = 0.004, eta(2) = 0.26) and lactate dehydrogenase (P < 0.001, eta(2) = 0.40) concentrations increased in both groups but there were no changes over time for any inflammatory markers. These results suggest that immediate post-match cold-water immersion does not affect physical test performance or indices of muscle damage and inflammation but does reduce the perception of general fatigue and leg soreness between matches in tournaments.
Full Text Available PURPOSE: To determine the volume and degree of asymmetry of the rectus abdominis muscle (RA in professional soccer players. METHODS: The volume of the RA was determined using magnetic resonance imaging (MRI in 15 professional male soccer players and 6 non-active male control subjects. RESULTS: Soccer players had 26% greater RA volume than controls (P<0.05, due to hypertrophy of both the dominant (28% greater volume, P<0.05 and non-dominant (25% greater volume, P<0.01 sides, after adjusting for age, length of the RA muscle and body mass index (BMI as covariates. Total volume of the dominant side was similar to the contralateral in soccer players (P = 0.42 and in controls (P = 0.75 (Dominant/non-dominant = 0.99, in both groups. Segmental analysis showed a progressive increase in the degree of side-to-side asymmetry from the first lumbar disc to the pubic symphysis in soccer players (r = 0.80, P<0.05 and in controls (r = 0.75, P<0.05. The slope of the relationship was lower in soccer players, although this trend was not statistically significant (P = 0.14. CONCLUSIONS: Professional soccer is associated with marked hypertrophy of the rectus abdominis muscle, which achieves a volume that is 26% greater than in non-active controls. Soccer induces the hypertrophy of the non-dominant side in proximal regions and the dominant side in regions closer to pubic symphysis, which attenuates the pattern of asymmetry of rectus abdominis observed in non-active population. It remains to be determined whether the hypertrophy of rectus abdominis in soccer players modifies the risk of injury.
Fessi, Mohamed Saifeddin; Nouira, Sabeur; Dellal, Alexandre; Owen, Adam; Elloumi, Mohamed; Moalla, Wassim
Perceived changes due to training monotony, strain, sleep, stress, fatigue, muscle soreness and the influence of specific training sessions on the affective valence were explored in professional soccer players. Seventeen players completed the Hooper questionnaire, the ratings of perceived exertion and feeling scale (FS) every training/match day before and during the soccer season. Higher players' training loads were recorded during pre-season when compared with in-season period (2558.1 ± 262.4 vs. 1642.8 ± 169.3 a.u., p muscle soreness in pre-season were higher than those observed during in-season (p training sessions, including technical/tactical work, induced an improved feeling score but linked with a lower training load when compared with sessions focus on physical emphasis (p training induces a significantly more strenuous and exhausting demands on professional soccer players compared with the in-season period at the elite level.
Full Text Available The aim of the study was to determine the mechanical and neuromuscular profile of knee extensor and flexor muscles in professional soccer players at the start of the pre-season, and to calculate percentages for symmetry, as well as examine differences according to the player’s positional role. The vastus medialis (VM, vastus lateralis (VL, rectus femoris (RF and biceps femoris (BF of 16 professional soccer players were evaluated by means of tensiomyography (TMG on the first day of the pre-season. A paired-samples t test (p < .05 was used to compare the dominant and non-dominant lower limb. One-way ANOVA was applied, with the positional role as an independent factor. No differences were observed between the dominant and non-dominant leg. The highest degree of symmetry corresponded to the VM (92.5 ± 2.7%, and the lowest to the BF (80.7 ± 10.9%. The positional role was associated with significant differences in some of the variables for the BF, RF and VM, although only the half-relaxation time in the BF and the time to sustain force in the VM differed across all the playing positions considered. TMG was shown to be a useful way of evaluating the neuromuscular characteristics of soccer players at the start of the pre-season, and of establishing baseline values for individual players.
Bianco, Antonino; Spedicato, Mirco; Petrucci, Marco; Messina, Giuseppe; Thomas, Ewan; Nese Sahin, Fatma; Paoli, Antonio; Palma, Antonio
Background: The effects of synthetic surfaces on the risk of injuries is still debated in literature and the majority of published data seems to be contradictory. For such reasons the understanding of injury incidence on such surfaces, especially in youth sport, is fundamental for injury prevention. Objectives: The aim of this study was to prospectively report the epidemiology of injuries in young football players, playing on artificial turfs, during a one sports season. Patients and Methods: 80 young male football players (age 16.1 ± 3.7 years; height 174 ± 6.6 cm; weight 64.2 ± 6.3 kg) were enrolled in a prospective cohort study. The participants were then divided in two groups; the first included players age ranging from 17 to 19 (OP) whereas the second included players age ranging from 13 to 16 (YP). Injury incidence was recorded prospectively, according to the consensus statement for soccer. Results: A total of 107 injuries (35 from the OP and 72 from the YP) were recorded during an exposure time of 83.760 hours (incidence 1.28/1000 per player hours); 22 during matches (incidence 2.84/1000 per player hours, 20.5%) and 85 during training (incidence 1.15/1000 per player hours, 79.5%). Thigh and groin were the most common injury locations (33.6% and 21.5%, respectively) while muscle injuries such as contractures and strains were the most common injury typologies (68.23%). No statistical differences between groups were displayed, except for the rate of severe injuries during matches, with the OP displaying slightly higher rates compared to the YP. Severe injuries accounted for 10.28% of the total injuries reported. The average time lost due to injuries was 14 days. Re-injuries accounted for 4.67% of all injuries sustained during the season. Conclusions: In professional youth soccer injury rates are reasonably low. Muscle injuries are the most common type of injuries while groin and thigh the most common locations. Artificial turf pitches don’t seem to
Rowat, Owain; Fenner, Jonathan; Unnithan, Viswanath
The aim of this study was to evaluate whether physical performance characteristics could be a better predictor than technical skills in determining the technical level of county soccer players in a match situation. With institutional ethics approval, 25 male youth soccer players aged 16-18.5 years from a professional soccer academy in South East Asia were selected and height and body mass were recorded. Players were tested for sexual maturity (pubertal development scale [PDS] self-assessment), aerobic capacity (yo-yo intermittent recovery test level 1 [YYIR1]), repeated sprint ability (7 x 35 m sprints) acceleration (15 m sprint) and four soccer skills tests (dribble with pass, dribbling speed, passing and shooting accuracy). Players' technical ability during match play was assessed in small-sided games of soccer (5 v 5) using a novel game technical scoring chart (scoring chart completed by coaches to assess technical performance in a match situation) developed from criteria (e.g., first touch, dribbling and two footedness) used by youth soccer coaches for talent identification. A Spearman's rank correlation showed the YYIR1 test and 15 m sprint test were limited in predicting technical match performance (r=0.03, P=0.88, r=-0.23, P=0.32 respectively). A Pearson product moment correlation showed that the repeated sprint test was also limited in predicting technical match performance (r=-0.34, P=0.14). A dribbling skill with a pass was found to be the best determinant of a player's technical ability in a match (r=-0.57, P=0.00). Talent identification and selection programs in Asian youth soccer should include a dribbling skill performed with a pass.
Sérgio T. da Fonseca
. However, there is a paucity of data that characterizes the muscular performance in Brazilian professional soccer athletes. Therefore, the objective of this study was to make a descriptive analysis of parameters related to the muscular performance of this population. METHODS: The sample of this study was composed of 117 athletes belonging to professional soccer clubs in Minas Gerais State. In order to evaluate the muscular performance of the athletes, an isokinetic dynamometer was used and the tests involved maximum voluntary contractions of the selected muscles. Hip abductors and adductors were assessed at the speeds of 30º/s, 60º/s and 120º/s; knee flexors and extensors at 60º/s, 180º/s and 300º/s; and ankle dorsiflexors, plantarflexors, invertors and evertors at 30º/s, 60º/s and 180º/s. Descriptive statistics were used to present the normative data and paired t-tests were used to identify significant differences between legs considering the parameters evaluated in this study. RESULTS: This study generated normative data to characterize the profile of Brazilian professional soccer players relative to their capacity of producing torque, muscle work and power. Significant differences were observed between legs considering some of the study's variables. CONCLUSION: The established normative data can be used as reference values in the prevention, training and rehabilitation of the athletes. In addition, these data may be used as reference for future studies with the objective of testing the association between muscular performance and incidence of injury in soccer practice.
Full Text Available There is an ongoing concern about the risk of injury to the spine in professional rugby players. The objective of this study was to investigate the prevalence of vertebral fracture using vertebral fracture assessment (VFA dual energy X-ray absorptiometry (DXA imaging in professional male rugby players. Ninety five professional rugby league (n = 52 and union (n = 43 players (n = 95; age 25.9 (SD 4.3 years; BMI: 29.5 (SD 2.9 kg.m2 participated in the research. Each participant received one VFA, and one total body and lumbar spine DXA scan (GE Lunar iDXA. One hundred and twenty vertebral fractures were identified in over half of the sample by VFA. Seventy four were graded mild (grade 1, 40 moderate (grade 2 and 6 severe (grade 3. Multiple vertebral fractures (≥2 were found in 37 players (39%. There were no differences in prevalence between codes, or between forwards and backs (both 1.2 v 1.4; p>0.05. The most common sites of fracture were T8 (n = 23, T9 (n = 18 and T10 (n = 21. The mean (SD lumbar spine bone mineral density Z-score was 2.7 (1.3 indicating high player bone mass in comparison with age- and sex-matched norms. We observed a high number of vertebral fractures using DXA VFA in professional rugby players of both codes. The incidence, aetiology and consequences of vertebral fractures in professional rugby players are unclear, and warrant timely, prospective investigation.
R. Agricola (Rintje); J.H.J.M. Bessems (Gert); A.Z. Ginai (Abida); M.P. Heijboer (Rien); R.A. van der Heijden (Rianne); J.A.N. Verhaar (Jan); H.H. Weinans (Harrie); J.H. Waarsing (Jan)
textabstractBackground: Cam impingement is a well-recognized cause of hip pain and might cause osteoarthritis of the hip. Clinically, cam impingement is mostly observed in young, active male patients, but only a few studies have focused on the manifestation of cam-type deformities during skeletal
Varley, Matthew C; Gabbett, Tim; Aughey, Robert J
Abstract We compared the match activity profiles of elite footballers from Australian football (AF), rugby league (RL) and soccer (SOC), using identical movement definitions. Ninety-four elite footballers from AF, RL or SOC clubs in Australia participated in this study. Movement data were collected using a 5-Hz global positioning system from matches during the 2008-2011 competitive seasons, including measures of velocity, distance, acceleration and bouts of repeat sprints (RS). Australian footballers covered the greatest relative running distances (129 ± 17 m.min -1 ) compared to RL (97 ± 16 m.min -1 ) and SOC (104 ± 10 m.min -1 ) (effect size [ES]; 1.0-2.8). The relative distance covered (4.92 ± 2.10 m.min -1 vs. 5.42 ± 2.49 m.min -1 ; 0.74 ± 0.78 m.min -1 vs. 0.97 ± 0.80 m.min -1 ) and the number of high-velocity running (0.4 ± 0.2 no.min -1 vs. 0.4 ± 0.2 no.min -1 ) and sprint (0.06 ± 0.06 no.min -1 vs. 0.08 ± 0.07 no.min -1 ) efforts between RL and SOC players were similar (ES; 0.1-0.3). Rugby league players undertook the highest relative number of accelerations (1.10 ± 0.56 no.min -1 ). RS bouts were uncommon for all codes. RL and SOC players perform less running than AF players, possibly due to limited open space as a consequence of field size and code specific rules. While training in football should be code specific, there may be some transference of conditioning drills across codes.
The purpose of this study was to analyze the leadership power perceptions of soccer coaches and soccer players according to their educational levels. Data were collected from 165 male soccer coaches and 870 male soccer players. Adapted versions of the "Power in Soccer Questionnaire-Other", the "Power in Soccer Questionnaire-Self" and an "information form" were used for data collection, and collected data were analyzed by the Kruskal-Wallis and the Mann-Whitney Tests. Analysis of the Power in Soccer Questionnaire-Other revealed significant differences between soccer players' level of education and their perception of Coercive Power (pleadership powers between coaches and players might create communication and performance problems in soccer.
The influence of modern studded and bladed soccer boots and sidestep cutting on noncontact knee loading during match play conditions is not fully understood. Modern soccer boot type and sidestep cutting compared with straight-ahead running do not significantly influence knee internal tibia axial and valgus moments, anterior joint forces, and flexion angles. Controlled laboratory study. Fifteen professional male outfield soccer players undertook trials of straight-ahead running and sidestep cutting at 30 degrees and 60 degrees with a controlled approach velocity on a Fédération Internationale de Football Association (FIFA) approved soccer surface. Two bladed and 2 studded soccer boots from 2 manufacturers were investigated. Three-dimensional inverse dynamics analysis determined externally applied internal/external tibia axial and valgus/varus moments, anterior forces, and flexion angles throughout stance. The soccer boot type imparted no significant difference on knee loading for each maneuver. Internal tibia and valgus moments were significantly greater for sidestep cutting at 30 degrees and 60 degrees compared with straight-ahead running. Sidestep cutting at 60 degrees compared with straight-ahead running significantly increased anterior joint forces. Varying soccer boot type had no effect on knee loading for each maneuver, but sidestep cutting significantly increased internal tibia and valgus moments and anterior joint forces. Sidestep cutting, irrespective of the modern soccer boot type worn, may be implicated in the high incidence of noncontact soccer anterior cruciate ligament injuries by significantly altering knee loading.
Horsley Ian G
Full Text Available Abstract Objective To identify posture types that exist in professional rugby players, and compare them with a population of non-overhead athletes in order to identify possible relationships towards the potential for shoulder injuries. Design Observational design Setting: Sports Medicine Clinic Participants: Convenience sample Methodology: Static assessment of posture was carried out in standing, active and passive range of glenohumeral motion, and isometric strength was carried out in accordance with previously recorded protocols. Interventions Nil Outcome Measures: Observational classification of posture, active and passive range of glenohumeral joint range of motion, isometric strength of selected muscle groups, selected muscle flexibility and Hawkins and Neer impingement tests. Results There was a significant difference on range of motion between the two groups (0.025–0.000, isometric middle (0.024–0.005, and lower trapezius (0.01–0.001. Conclusion: There were significant differences between strength and flexibility of muscles around the shoulder girdle between professional rugby players and a control group of professional non-overhead athletes.
What do Italy and Germany have in common? The world's largest PV markets and world class soccer. But while PV systems are frequently found on the rooftops of Germany's soccer stadiums, Italy has left this potential largely untapped.
Orishimo, Karl F; Kremenic, Ian J; Pappas, Evangelos; Hagins, Marshall; Liederbach, Marijeanne
The incidence of anterior cruciate ligament injuries among dancers is much lower than that among team sport athletes and no clear gender disparity has been reported in the dance population. Although numerous studies have observed differences in lower extremity landing biomechanics between male and female athletes, there is currently little research examining the landing biomechanics of male and female dancers. Comparing landing biomechanics within this population may help explain the lower overall anterior cruciate ligament injury rates and the lack of gender disparity. Due to the fact that dancers receive jump-specific and balance-specific training from a very young age, we hypothesized that there would be no gender differences in drop-landing biomechanics in professional dancers. Controlled laboratory study. Kinematics and ground-reaction forces were recorded as 33 professional modern and ballet dancers (12 men and 21 women) performed single-legged drop landings from a 30-cm platform. Joint kinematics and kinetics were compared between genders. No gender differences in joint kinematics or kinetics were found during landings (multivariate analysis of variance: P = .490 and P = .175, respectively). A significant relationship was found between the age at which the dancers began training and the peak hip adduction angle during landing (r = .358, P = .041). In executing a 30-cm drop landing, male and female dancers exhibited similar landing strategies and avoided landing patterns previously associated with increased injury rates. Commonly reported biomechanical differences between men and women, as well as the gender disparity among athletes in the incidence of ACL injuries, may be the result of inadequate experience in proper balance and landing technique rather than intrinsic gender factors. Beginning jump-specific and balance-specific training at an early age may counteract the potentially harmful adaptations in landing biomechanics observed in female athletes
Mohammad Fayiz Abumoh'd
Full Text Available This study investigated the effect of caffeine contained in sports drink on hormones producing energy and sprint test performance in male soccer players. Twelve participants (25.97 ± 2.70 y performed the test under thre e conditions (one week apart: caffeine with sports drink (SD-CAF, sports drink (SD, and placebo (PLA. Using a double-blind, placebo-controlled, randomized, crossover protocol, participants performed SD-CAF trial (5 mg/kg of caffeine contained in 300 ml of sports drink 30 minutes prior to sprinting test (7 × 30 m, SD trial (solely 300 ml of sports drink 30 minutes prior to sprinting test, or placebo. Blood analysis indicated significantly higher level of free thyroxine in SD-CAF (21.450 ± 3.048 compared to SD (18.742 ± 1.151 and PLA (16.983 ± 1.783. Similar findings existed regarding insulin (P 0.05. No significant differences were observed between trials in first–fourth repetitions (P > 0.05. Time of fifth-seventh repetitions were significantly lower in SD-CAF compared to SD and PLA (P < 0.05, and were significantly lower in SD than that in PLA (P < 0.05. The time of 7th repetition was (4.331 ± 0.210, 4.610 ± 0.197, 4.81 6 ± 0.171 s for SD-CAF, SD, and PLA, respectively; P < 0.05. In conclusion, caffeine interferes hormones that are responsible for producing energy which in turn have a positive effect on repeated sprint bouts.
Folgado, Hugo; Gonçalves, Bruno; Sampaio, Jaime
This study aimed to identify changes in tactical, physical and physiological performances in large-sided games during the preseason of elite footballers. Thirty professional football players participated in several GK+8vs.8+GK large-sided games across the first four weeks of the season. Players were monitored by GPS units and heart rate monitors to quantify physical, physiological and tactical performances. The variables were compared according to the preseason period, players' positioning and professional experience. The training situation promoted similar physiological responses during the first and the last training period. However, players were revealed to have higher levels of positional synchronization during the last preseason period, indicating an improved tactical performance. Tactical variables seem to reflect the improvement of players' performance during the preseason, measured in large-sided games situation, while affecting both physical and physiological demands. These results highlight the potential of positioning derived variables, concurrently to physical and physiological variables, for football training optimization.
Hagen, Marco; Asholt, Johannes; Lemke, Martin; Lahner, Matthias
It is currently unclear how participation in different sports affects the angle-specific subtalar pronator and supinator muscle strength and pronator-to-supinator strength ratio (PSR). Based on the hypothesis that both differences sport-related patterns of play and foot-ground interaction may lead to sport-specific muscle adaptations, this study compared the angle specific pronator and supinator strength capacity of handball and soccer players. Eighteen healthy male handball and 19 soccer players performed maximum isometric voluntary isometric contractions using a custom-made testing apparatus. Peak pronator (PPT) and supinator torques (PST), pronator and supinator strength curves (normalised to the peak torque across all joint angles) and PSR were measured in five anatomical joint angles across the active subtalar range of motion (ROM). All analysed parameters were dependent on the subtalar joint angle. The ANOVA revealed significant `joint angle' × `group' interactions on PPT, pronator strength curves and PSR. No group differences were found for active subtalar ROM. In previously uninjured handball and soccer athletes, there were intrinsic differences in angle-specific subtalar pronator muscle strength. The lower PSR, which was found in the most supinated angle, can be seen as a risk factor for sustaining an ankle sprain.
Gouttebarge, Vincent; Aoki, Haruhito; Lambert, Michael; Stewart, William; Kerkhoffs, Gino
Recent reports suggest that exposure to repetitive concussions in sports is associated with an increased risk of symptoms of distress, anxiety and depression, sleep disturbance or substance abuse/dependence (typically referred as symptoms of common mental disorders[CMD]) and of later development of neurodegenerative disease, in particular chronic traumatic encephalopathy (CTE). The primary aim of this study was to explore the relationship between sports career-related concussions and the subsequent occurrence of symptoms of CMD among former male professional athletes retired from football (soccer), ice hockey and rugby (union). Cross-sectional analyses were performed on baseline electronic questionnaires from three prospective cohort studies among former male professional athletes retired from football (soccer), ice hockey and rugby (union). The number of confirmed concussions was examined through a single question, while symptoms of distress, anxiety and depression, sleep disturbance and adverse alcohol use were assessed using validated questionnaires. From 1,957 former professional athletes contacted, a total of 576 (29%) completed the questionnaire. Of these, 23% had not incurred a concussion during their career, 34% had two or three, 18% four or five, and 11% six or more concussions. The number of sports career-related concussions was a predictor for all outcome measures (β = 0.072-0.109; P ≤ 0.040). Specifically, former professional athletes who reported a history of four or five concussions were approximately 1.5 times more likely to report symptoms of CMD, rising to a two- to five-fold increase in those reporting a history of six or more sports career-related concussions. These data demonstrate an association between exposure to sports concussion and subsequent risk of symptoms of CMD in former professional athletes across a range of contact sports. Further work to explore the association between sports concussion and symptoms of CMD is required; in
Taradaj, J; Halski, T; Kucharzewski, M; Walewicz, K; Smykla, A; Ozon, M; Slupska, L; Dymarek, R; Ptaszkowski, K; Rajfur, J; Pasternok, M
The aim of this study was to assess the clinical efficacy and safety of NMES program applied in male soccer players (after ACL reconstruction) on the quadriceps muscle. The 80 participants (NMES = 40, control = 40) received an exercise program, including three sessions weekly. The individuals in NMES group additionally received neuromuscular electrical stimulation procedures on both right and left quadriceps (biphasic symmetric rectangular pulses, frequency of impulses: 2500 Hz, and train of pulses frequency: 50 Hz) three times daily (3 hours of break between treatments), 3 days a week, for one month. The tensometry, muscle circumference, and goniometry pendulum test (follow-up after 1 and 3 months) were applied. The results of this study show that NMES (in presented parameters in experiment) is useful for strengthening the quadriceps muscle in soccer athletes. There is an evidence of the benefit of the NMES in restoring quadriceps muscle mass and strength of soccer players. In our study the neuromuscular electrical stimulation appeared to be safe for biomechanics of knee joint. The pathological changes in knee function were not observed. This trial is registered with Australian and New Zealand Clinical Trials Registry ACTRN12613001168741.
Full Text Available The aim of this study was to assess the clinical efficacy and safety of NMES program applied in male soccer players (after ACL reconstruction on the quadriceps muscle. The 80 participants (NMES = 40, control = 40 received an exercise program, including three sessions weekly. The individuals in NMES group additionally received neuromuscular electrical stimulation procedures on both right and left quadriceps (biphasic symmetric rectangular pulses, frequency of impulses: 2500 Hz, and train of pulses frequency: 50 Hz three times daily (3 hours of break between treatments, 3 days a week, for one month. The tensometry, muscle circumference, and goniometry pendulum test (follow-up after 1 and 3 months were applied. The results of this study show that NMES (in presented parameters in experiment is useful for strengthening the quadriceps muscle in soccer athletes. There is an evidence of the benefit of the NMES in restoring quadriceps muscle mass and strength of soccer players. In our study the neuromuscular electrical stimulation appeared to be safe for biomechanics of knee joint. The pathological changes in knee function were not observed. This trial is registered with Australian and New Zealand Clinical Trials Registry ACTRN12613001168741.
Owen, Adam L; Wong, Del P; McKenna, Michael; Dellal, Alexandre
This study aims to examine the difference in heart rate (HR) responses and technical activities placed upon European elite players when exposed to 2-sided games differing in the number of players and playing area. Fifteen male soccer players from a Scottish Premier League team (26.3 ± 4.85 years, 182.4 ± 6.99 cm, 79.5 ± 8.05 kg, VO2max of 54.36 ± 5.45 ml·kg(-1)·min(-1)) performed both small (3 vs. 3 plus goalkeepers) and large (9 vs. 9 plus goalkeepers) sided games each lasting for 3 × 5 minutes interspersed with 4-minute passive recovery during the 2009-2010 season. The HR responses and players' technical actions were recorded throughout all sided games. Results show that small-sided games (SSG) induced significantly (p games. Furthermore, during SSGs, players spent significantly longer time in the >85% maximal HR zone (p games. Technical analysis revealed a large practical difference (effect size ranged from 1.5 to 21.2) between small- and large-sided games: less number of blocks, headers, interceptions, passes, and receives but more dribbles, shots, and tackles in SSG. Furthermore, SSG induced significantly lesser total ball contacts per game (p games. The different technical requirements also enable coaches to carry out training games more suitable to specific playing positions such as SSG for midfielders (more dribbles, tackles, and ball contacts per player) strikers (more shots), and large-sided games for defender (more blocks, headers, and interceptions).
Full Text Available Professional soccer players have a lengthy playing season, throughout which high levels of physical stress are maintained. The following recuperation period, before starting the next pre-season training phase, is generally considered short but sufficient to allow a decrease in these stress levels and therefore a reduction in the propensity for injury or musculoskeletal tissue damage. We hypothesised that these physical extremes influence the body composition, blood flow, and endothelial/immune function, but that the recuperation may be insufficient to allow a reduction of tissue stress damage. Ten professional football players were examined at the end of the playing season, at the end of the season intermission, and after the next pre-season endurance training. Peripheral blood flow and body composition were assessed using venous occlusion plethysmography and DEXA scanning respectively. In addition, selected inflammatory and immune parameters were analysed from blood samples. Following the recuperation period a significant decrease of lean body mass from 74.4+/-4.2 kg to 72.2+/-3.9 kg was observed, but an increase of fat mass from 10.3+/-5.6 kg to 11.1+/-5.4 kg, almost completely reversed the changes seen in the pre-season training phase. Remarkably, both resting and post-ischemic blood flow (7.3+/-3.4 and 26.0+/-6.3 ml/100 ml/min respectively, were strongly reduced during the playing and training stress phases, but both parameters increased to normal levels (9.0+/-2.7 and 33.9+/-7.6 ml/100 ml/min during the season intermission. Recovery was also characterized by rising levels of serum creatinine, granulocytes count, total IL-8, serum nitrate, ferritin, and bilirubin. These data suggest a compensated hypo-perfusion of muscle during the playing season, followed by an intramuscular ischemia/reperfusion syndrome during the recovery phase that is associated with muscle protein turnover and inflammatory endothelial reaction, as demonstrated by i
Vitale, Jacopo A; Bonato, Matteo; Galasso, Letizia; La Torre, Antonio; Merati, Giampiero; Montaruli, Angela; Roveda, Eliana; Carandente, Franca
The influence of the chronotype on the sleep quality in male collegiate soccer players in response to acute high intensity interval training (HIIT) performed at two different times of day was evaluated. The sleep quality was poorer in the morning-type than in the evening-type players after the evening HIIT session, whereas no significant changes in the sleep quality of the two chronotypes after the morning HIIT session was observed. The results suggest that an athlete's chronotype should be taken into account when scheduling training sessions and to promote faster recovery processes.
Williams, C A
Relationships between empathy and burnout and possible confounding influences of sex and profession were explored in a sample of 492 male and female nurses, social workers, and teachers. Respondents completed Mehrabian's Emotional Empathy Scale, Stotland's Fantasy-Empathy Scale, and the Maslach Burnout Inventory (MBI). There were no main effects of profession on empathy or burnout variables. There was, however, an interaction effect of sex and profession on depersonalization, which was accounted for by subjects in social work and teaching. Women had significantly higher empathy scores than men; however, men had higher scores than male normative groups. Age related negatively to depersonalization and emotional exhaustion for women, whereas percentage of work time spent in direct practice correlated with depersonalization for men. The possibility that empathy and burnout might represent opposite poles of the same underlying construct was examined but not found. Instead, emotional empathy was significantly positively correlated with both emotional exhaustion and personal accomplishment, whereas emotional exhaustion was also positively related to depersonalization. It is hypothesized that high emotional empathy may predispose helping professionals to emotional exhaustion and that emotional exhaustion, if not mediated by personal accomplishment, may lead to the development of depersonalization. This more complex, interactive model of the empathy-burnout relationship needs longitudinal study.
Lombardi, Giovanni; Vitale, Jacopo Antonino; Logoluso, Sergio; Logoluso, Giovanni; Cocco, Nino; Cocco, Giulio; Cocco, Antonino; Banfi, Giuseppe
Adequate plasmatic Vitamin D levels are crucial to maintain calcium homeostasis and bone metabolism both in the general population and in athletes. Correct dietary supply and a regular sun exposure are fundamental for allowing the desired and effective fitness level. Past studies highlighted a scenario of Vitamin D insufficiency among professional soccer players in several countries, especially in North Europe, whilst a real deficiency in athletes is rare. The typical seasonal fluctuations of Vitamin D are wrongly described transversally in athletes belonging to teams that play at different latitudes and a chronobiologic approach studying the Vitamin D circannual rhythm in soccer players has not been described yet. Therefore, we studied plasma vitamin D, cortisol, testosterone, and creatin kinase (CK) concentrations in three different Italian professional teams training at the same latitude during a period of two consecutive competitive seasons (2013 and 2014). In this retrospective observational study, 167 professional soccer players were recruited (mean age at sampling 25.1 ± 4.7 years) and a total of 667 blood drawings were carried out to determine plasma 25(OH)D, serum cortisol, serum testosterone and CK levels. Testosterone to cortisol ratio (TC) was calculated based as a surrogate marker of overtraining and psychophysical stress and each athlete was drawn until a maximum of 5 times per season. Data extracted by a subgroup of players that underwent at least 4 sample drawings along a year (N = 45) were processed with the single and population mean cosinor tests to evaluate the presence of circannual rhythms: the amplitude (A), acrophase (Φ) and the MESOR (M) are described. In total, 55 players (32.9%) had an insufficient level of 25(OH)D during the seasons and other 15 athletes (9.0%) showed, at least once, a deficiency status of Vitamin D. The rhythmometric analyses applied to the data of Vitamin D revealed the presence of a significant circannual rhythm (p
Bettonviel A, E O; Brinkmans N, Y J; Russcher, Kris; Wardenaar, Floris C; Witard, Oliver C
The nutritional status of elite soccer players across match, postmatch, training and rest days has not been defined. Recent evidence suggests the pattern of dietary protein intake impacts the daytime turnover of muscle proteins and, as such, influences muscle recovery. We assessed the nutritional status and daytime pattern of protein intake in senior professional and elite youth soccer players and compared findings against published recommendations. Fourteen senior professional (SP) and 15 youth elite (YP) soccer players from the Dutch premier division completed nutritional assessments using a 24-hr web-based recall method. Recall days consisted of a match, postmatch, rest, and training day. Daily energy intake over the 4-day period was similar between SP (2988 ± 583 kcal/day) and YP (2938 ± 465 kcal/day; p = .800). Carbohydrate intake over the combined 4-day period was lower in SP (4.7 ± 0.7 g·kg-1 BM·day-1) vs. YP (6.0 ± 1.5 g·kg-1 BM·day-1, p = .006) and SP failed to meet recommended carbohydrate intakes on match and training days. Conversely, recommended protein intakes were met for SP (1.9 ± 0.3 g·kg-1 BM·day-1) and YP (1.7 ± 0.4 g·kg-1 BM·day-1), with no differences between groups (p = .286). Accordingly, both groups met or exceeded recommended daily protein intakes on individual match, postmatch, rest and training days. A similar "balanced" daytime pattern of protein intake was observed in SP and YP. To conclude, SP increased protein intake on match and training days to a greater extent than YP, however at the expense of carbohydrate intake. The daytime distribution of protein intake for YP and SP aligned with current recommendations of a balanced protein meal pattern.
Campos-Vazquez, Miguel Angel; Mendez-Villanueva, Alberto; Gonzalez-Jurado, Jose Antonio; León-Prados, Juan Antonio; Santalla, Alfredo; Suarez-Arrones, Luis
To describe the internal training load (ITL) of common training sessions performed during a typical week and to determine the relationships between different indicators of ITL commonly employed in professional football (soccer). Session-rating-of-perceived-exertion TL (sRPE-TL) and heart-rate- (HR) derived measurements of ITL as Edwards TL and Stagno training impulses (TRIMPMOD) were used in 9 players during 3 periods of the season. The relationships between them were analyzed in different training sessions during a typical week: skill drills/circuit training + small-sided games (SCT+SSGs), ball-possession games+technical-tactical exercises (BPG+TTE), tactical training (TT), and prematch activation (PMa). HR values obtained during SCT+SSGs and BPG+TTE were substantially greater than those in the other 2 sessions, all the ITL markers and session duration were substantially greater in SCT+SSGs than in any other session, and all ITL measures in BPG+TTE were substantially greater than in TT and PMa sessions. Large relationships were found between HR>80% HRmax and HR>90% HRmax vs sRPE-TL during BPG+TTE and TT sessions (r=.61-.68). Very large relationships were found between Edwards TL and sRPE-TL and between TRIMPMOD and sRPE-TL in sessions with BPG+TTE and TT (r=.73-.87). Correlations between the different HR-based methods were always extremely large (r=.92-.98), and unclear correlations were observed for other relationships between variables. sRPE-TL provided variable-magnitude within-individual correlations with HR-derived measures of training intensity and load during different types of training sessions typically performed during a week in professional soccer. Caution should be applied when using RPE- or HR-derived measures of exercise intensity/load in soccer training interchangeably.
Schuermans, Joke; Danneels, Lieven; Van Tiggelen, Damien; Palmans, Tanneke; Witvrouw, Erik
With their unremittingly high incidence rate and detrimental functional repercussions, hamstring injuries remain a substantial problem in male soccer. Proximal neuromuscular control ("core stability") is considered to be of key importance in primary and secondary hamstring injury prevention, although scientific evidence and insights on the exact nature of the core-hamstring association are nonexistent at present. The muscle activation pattern throughout the running cycle would not differ between participants based on injury occurrence during follow-up. Case-control study; Level of evidence, 3. Sixty amateur soccer players participated in a multimuscle surface electromyography (sEMG) assessment during maximal acceleration to full-speed sprinting. Subsequently, hamstring injury occurrence was registered during a 1.5-season follow-up period. Hamstring, gluteal, and trunk muscle activity time series during the airborne and stance phases of acceleration were evaluated and statistically explored for a possible causal association with injury occurrence and absence from sport during follow-up. Players who did not experience a hamstring injury during follow-up had significantly higher amounts of gluteal muscle activity during the front swing phase ( P = .027) and higher amounts of trunk muscle activity during the backswing phase of sprinting ( P = .042). In particular, the risk of sustaining a hamstring injury during follow-up lowered by 20% and 6%, with a 10% increment in normalized muscle activity of the gluteus maximus during the front swing and the trunk muscles during the backswing, respectively ( P < .024). Muscle activity of the core unit during explosive running appeared to be associated with hamstring injury occurrence in male soccer players. Higher amounts of gluteal and trunk muscle activity during the airborne phases of sprinting were associated with a lower risk of hamstring injuries during follow-up. Hence, the present results provide a basis for improved
Benedito Sergio Denadai
Full Text Available The purposes of this study were to determine whether low intensity resistance training combined with blood flow restriction (LI-BFR could affect the concentric hamstrings/quadriceps muscle strength ratio (Hcon:Qcon of professional soccer players with Hcon:Qcon imbalance (Study 1, and whether hamstrings strength response observed after LI-BFR is associated with muscle hypertrophy (Study 2. In the Study 1, athletes were randomly divided into a training group (n = 6 and a control group (n = 5. In the Study 2, all athletes (n = 11 have performed the training programme. The athletes participated in a 6-week (twice a week supervised training programme (unilateral knee flexion at 30% 1RM consisting of 12 training sessions. Peak concentric torque of knee flexors (+8%; P < 0.001 and Hcon:Qcon (+9%; P < 0.01 were significantly increased after LI-BFR. Moreover, the cross sectional area (CSA of the hamstrings was significantly increased (+10%; P < 0.001 after LI-BFR. Thus, the addition of hamstrings strength training programme using LI-BFR during preseason is able to enhance both Hcon:Qcon and hamstrings CSA of professional soccer players with Hcon:Qcon imbalance.
Wesam Saleh A Al Attar; Najeebullah Soomro; Evangelos Pappas; Peter J Sinclair; Ross H Sanders
Question: Does adding a post-training Fédération Internationale de Football Association (FIFA) 11+ exercise program to the pre-training FIFA 11+ injury prevention program reduce injury rates among male amateur soccer players? Design: Cluster-randomised, controlled trial with concealed allocation. Participants: Twenty-one teams of male amateur soccer players aged 14 to 35 years were randomly assigned to the experimental group (n = 10 teams, 160 players) or the control group (n = 11 teams...
Full Text Available The objectives of this study were to examine the effects of a moderate intensity strength training on changes in critical velocity (CV, anaerobic running distance (D', sprint performance and Yo-Yo intermittent running test (Yo-Yo IR1 performances.two recreational soccer teams were divided in a soccer training only group (SO; n = 13 and a strength and soccer training group (ST; n = 13. Both groups were tested for values of CV, D', Yo-Yo IR1 distance and 30-m sprint time on two separate occasions (pre and post intervention. The ST group performed a concurrent 6-week upper and lower body strength and soccer training, whilst the SO group performed a soccer only training.after the re-test of all variables, the ST demonstrated significant improvements for both, YoYo IR1 distance (p = 0.002 and CV values (p<0.001 with no significant changes in the SO group. 30-m sprint performance were slightly improved in the ST group with significantly decreased performance times identified in the SO group (p<0.001. Values for D' were slightly reduced in both groups (ST -44.5 m, 95% CI = -90.6 to 1.6; SO -42.6 m, 95% CI = -88.7 to 3.5.combining a 6-week moderate strength training with soccer training significantly improves CV, Yo-Yo IR1 whilst moderately improving 30-m sprint performances in non-previously resistance trained male soccer players. Critical Velocity can be recommended to coaches as an additional valid testing tool in soccer.
Karsten, Bettina; Larumbe-Zabala, Eneko; Kandemir, Gokhan; Hazir, Tahir; Klose, Andreas; Naclerio, Fernando
The objectives of this study were to examine the effects of a moderate intensity strength training on changes in critical velocity (CV), anaerobic running distance (D'), sprint performance and Yo-Yo intermittent running test (Yo-Yo IR1) performances. two recreational soccer teams were divided in a soccer training only group (SO; n = 13) and a strength and soccer training group (ST; n = 13). Both groups were tested for values of CV, D', Yo-Yo IR1 distance and 30-m sprint time on two separate occasions (pre and post intervention). The ST group performed a concurrent 6-week upper and lower body strength and soccer training, whilst the SO group performed a soccer only training. after the re-test of all variables, the ST demonstrated significant improvements for both, YoYo IR1 distance (p = 0.002) and CV values (p<0.001) with no significant changes in the SO group. 30-m sprint performance were slightly improved in the ST group with significantly decreased performance times identified in the SO group (p<0.001). Values for D' were slightly reduced in both groups (ST -44.5 m, 95% CI = -90.6 to 1.6; SO -42.6 m, 95% CI = -88.7 to 3.5). combining a 6-week moderate strength training with soccer training significantly improves CV, Yo-Yo IR1 whilst moderately improving 30-m sprint performances in non-previously resistance trained male soccer players. Critical Velocity can be recommended to coaches as an additional valid testing tool in soccer.
Ostojic, Sergej M; Mazic, Sanja
The aim of this study was to examine the effects of a carbohydrate-electrolyte drink on specific soccer tests and performance. Twenty-two professional male soccer players volunteered to participate in the study. The players were allocated to two assigned trials ingesting carbohydrate-electrolyte drink (7% carbohydrates, sodium 24 mmol.l-1, chloride 12 mmol.l-1, potassium 3 mmol.l-1) or placebo during a 90 min on-field soccer match. The trials were matched for subjects' age, weight, height and maximal oxygen uptake. Immediately after the match, players completed four soccer-specific skill tests. Blood glucose concentration [mean (SD)] was higher at the end of the match-play in the carbohydrate-electrolyte trial than in the placebo trial (4.4 (0.3) vs. 4.0 (0.3) mmol.l-1, P carbohydrate-electrolyte trial finished the specific dribble test faster in comparison with subjects in the placebo trial (12.9 (0.4) vs. 13.6 (0.5) s, P carbohydrate-electrolyte trial as compared to the placebo trial (17.2 (4.8) vs. 15.1 (5.2), P carbohydrate-electrolyte solution improved soccer-specific skill performance and recovery after an on-field soccer match compared with ingestion of placebo. This suggests that soccer players should consume carbohydrate-electrolyte fluid throughout a game to help prevent deterioration in specific skill performance.
Landry, Scott C; McKean, Kelly A; Hubley-Kozey, Cheryl L; Stanish, William D; Deluzio, Kevin J
Female athletes are 2 to 8 times more likely than male athletes to injure the anterior cruciate ligament during a non-contact athletic maneuver. Identifying anterior cruciate ligament injury risk factors in female athletes may help with the development of preventive training programs aimed at reducing injury rates. Differences between genders in lower limb kinematics, kinetics, and neuromuscular patterns will be identified in an adolescent soccer population during an unanticipated side-cut maneuver. Controlled laboratory study. Forty-two elite adolescent soccer players (21 male and 21 female) performed an unanticipated side-cut maneuver, with the 3-dimensional kinematic, kinetic, and electromyographic lower limb data being analyzed using principal component analysis. The female athletes had higher gastrocnemius activity, normalized to maximal voluntary isometric contractions, and a mediolateral gastrocnemius activation imbalance that was not present in the male athletes during early stance to midstance of the side-cut. Female athletes demonstrated greater rectus femoris muscle activity throughout stance, and the only hamstring difference identified was a mediolateral activation imbalance in male athletes only. Female athletes performed the side-cut with less hip flexion and more hip external rotation and also generated a smaller hip flexion moment compared with the male athletes. This is the first study to identify gender-related differences in gastrocnemius muscle activity during an unanticipated cutting maneuver. The increased and imbalanced gastrocnemius muscle activity, combined with increased rectus femoris muscle activity and reduced hip flexion angles and moments in female subjects, may all have important contributing roles in the higher noncontact ACL injury rates observed in female athletes.
Tudisco, Cosimo; Bisicchia, Salvatore; Cosentino, Andrea; Chiozzi, Federica; Piva, Massimo
a wrong position of bone tunnels, in particular on the femur, is one of the most frequent causes of a failed anterior cruciate ligament (ACL) reconstruction. Several studies demonstrated that drilling the femoral tunnel through the antero-medial portal (AMP) allows a more anatomical placement on the lateral femoral condyle and higher knee stability, compared to trans-tibial (TT) technique. The aim of this study was to retrospectively evaluate two groups of soccer players operated on for ACL reconstruction according to either one of these two techniques. two groups of non-professional soccer players operated on for a single bundle ACL reconstruction with hamstrings autograft using either a TT (20 patients) or an AMP (23 patients) technique were retrospectively evaluated with KT-1000 arthrometer, manual pivot shift test, isokinetic test, the incremental treadmill-running test, athletic and sport specific tasks, and knee scores (IKDC, Lysholm and KOOS). the AMP group showed better results at pivot shift test and KOOS, but lower flexion angles at single leg squat test. There were no differences in all the other considered outcomes. the better rotational stability of the knee achieved in AMP group did not lead to significantly better clinical and functional results in our patients. Case-control study.
Harøy, Joar; Thorborg, Kristian; Serner, Andreas; Bjørkheim, André; Rolstad, Linn E; Hölmich, Per; Bahr, Roald; Andersen, Thor Einar
The FIFA 11+ was developed as a complete warm-up program to prevent injuries in soccer players. Although reduced hip adduction strength is associated with groin injuries, none of the exercises included in the FIFA 11+ seem to specifically target hip adduction strength. To investigate the effect on eccentric hip adduction strength of the FIFA 11+ warm-up program with or without the Copenhagen adduction exercise. Randomized controlled trial; Level of evidence, 1. We recruited 45 eligible players from 2 U19 elite male soccer teams. Players were randomized into 2 groups; 1 group carried out the standard FIFA 11+ program, while the other carried out the FIFA 11+ but replaced the Nordic hamstring exercise with the Copenhagen adduction exercise. Both groups performed the intervention 3 times weekly for 8 weeks. Players completed eccentric strength and sprint testing before and after the intervention. Per-protocol analyses were performed, and 12 players were excluded due to low compliance (FIFA 11+ program (-0.02 N·m/kg [-0.7%]; P = .69). Including the Copenhagen adduction exercise in the FIFA 11+ program increases eccentric hip adduction strength, while the standard FIFA 11+ program does not. Registration: Registration: ISRCTN13731446 (International Standard Randomised Controlled Trial Number registry).
Wesam Saleh A Al Attar
Trial registration: ACTRN12615001206516. [Al Attar WSA, Soomro N, Pappas E, Sinclair PJ, Sanders RH (2017 Adding a post-training FIFA 11+ exercise program to the pre-training FIFA 11+ injury prevention program reduces injury rates among male amateur soccer players: a cluster-randomised trial. Journal of Physiotherapy 63: 235–242
Solberg Nedrehagen Eirik
Full Text Available The aim of this study was to compare the effects of repeated sprints (RSA training and regular soccer training on Yo-Yo IR-1 and RSA performance (6 × 40 m shuttle sprints. Thirteen semi-professional female soccer players and nine amateur male soccer players were randomised into a repeated sprint group (RSG; n = 12 or a regular soccer training group (STG; n = 10. The RSG soccer players executed 3-4 sets of 4-6 repeated sprints (30 m with 180° directional changes weekly during the last eight weeks of the in-season. In parallel, the STG soccer players performed low- to moderate intensity soccer training in form of technical or tactical skills. The RSG showed 15% improvement in Yo-Yo IR-1 (p = 0.04; ES = 1.83 and their mean RSA times were reduced by 1.5% (p = 0.02; ES = 0.89. No significant changes were found for the STG (Yo-Yo IR-1, p = 0.13; RSA, p = 0.49. Comparing the groups, greater improvements were observed in Yo-Yo IR-1 for the RSG (p = 0.02; ES = 1.15, but not for the RSA (p = 0.23; ES = -0.33. Similar training volumes and intensities (% of HFmax were observed between the groups (p = 0.22 and p = 0.79. In conclusion, a weekly RSA session integrated into a regular soccer regime improved in-season RSA and Yo-Yo IR-1 performance compared to regular soccer training.
Full Text Available Executive functions might be important for successful performance in sports, particularly in team sports requiring quick anticipation and adaptation to continuously changing situations in the field. The executive functions motor inhibition, attention and visuospatial working memory were examined in highly talented soccer players. Eighty-four highly talented youth soccer players (mean age 11.9, and forty-two age-matched amateur soccer players (mean age 11.8 in the age range 8 to 16 years performed a Stop Signal task (motor inhibition, the Attention Network Test (alerting, orienting, and executive attention and a visuospatial working memory task. The highly talented soccer players followed the talent development program of the youth academy of a professional soccer club and played at the highest national soccer competition for their age. The amateur soccer players played at a regular soccer club in the same geographical region as the highly talented soccer players and play in a regular regional soccer competition. Group differences were tested using analyses of variance. The highly talented group showed superior motor inhibition as measured by stop signal reaction time (SSRT on the Stop Signal task and a larger alerting effect on the Attention Network Test, indicating an enhanced ability to attain and maintain an alert state. No group differences were found for orienting and executive attention and visuospatial working memory. A logistic regression model with group (highly talented or amateur as dependent variable and executive function measures that significantly distinguished between groups as predictors showed that these measures differentiated highly talented soccer players from amateur soccer players with 89% accuracy. Highly talented youth soccer players outperform youth amateur players on suppressing ongoing motor responses and on the ability to attain and maintain an alert state; both may be essential for success in soccer.
Verburgh, Lot; Scherder, Erik J A; van Lange, Paul A M; Oosterlaan, Jaap
Executive functions might be important for successful performance in sports, particularly in team sports requiring quick anticipation and adaptation to continuously changing situations in the field. The executive functions motor inhibition, attention and visuospatial working memory were examined in highly talented soccer players. Eighty-four highly talented youth soccer players (mean age 11.9), and forty-two age-matched amateur soccer players (mean age 11.8) in the age range 8 to 16 years performed a Stop Signal task (motor inhibition), the Attention Network Test (alerting, orienting, and executive attention) and a visuospatial working memory task. The highly talented soccer players followed the talent development program of the youth academy of a professional soccer club and played at the highest national soccer competition for their age. The amateur soccer players played at a regular soccer club in the same geographical region as the highly talented soccer players and play in a regular regional soccer competition. Group differences were tested using analyses of variance. The highly talented group showed superior motor inhibition as measured by stop signal reaction time (SSRT) on the Stop Signal task and a larger alerting effect on the Attention Network Test, indicating an enhanced ability to attain and maintain an alert state. No group differences were found for orienting and executive attention and visuospatial working memory. A logistic regression model with group (highly talented or amateur) as dependent variable and executive function measures that significantly distinguished between groups as predictors showed that these measures differentiated highly talented soccer players from amateur soccer players with 89% accuracy. Highly talented youth soccer players outperform youth amateur players on suppressing ongoing motor responses and on the ability to attain and maintain an alert state; both may be essential for success in soccer.
Verburgh, Lot; Scherder, Erik J. A.; van Lange, Paul A.M.; Oosterlaan, Jaap
Executive functions might be important for successful performance in sports, particularly in team sports requiring quick anticipation and adaptation to continuously changing situations in the field. The executive functions motor inhibition, attention and visuospatial working memory were examined in highly talented soccer players. Eighty-four highly talented youth soccer players (mean age 11.9), and forty-two age-matched amateur soccer players (mean age 11.8) in the age range 8 to 16 years performed a Stop Signal task (motor inhibition), the Attention Network Test (alerting, orienting, and executive attention) and a visuospatial working memory task. The highly talented soccer players followed the talent development program of the youth academy of a professional soccer club and played at the highest national soccer competition for their age. The amateur soccer players played at a regular soccer club in the same geographical region as the highly talented soccer players and play in a regular regional soccer competition. Group differences were tested using analyses of variance. The highly talented group showed superior motor inhibition as measured by stop signal reaction time (SSRT) on the Stop Signal task and a larger alerting effect on the Attention Network Test, indicating an enhanced ability to attain and maintain an alert state. No group differences were found for orienting and executive attention and visuospatial working memory. A logistic regression model with group (highly talented or amateur) as dependent variable and executive function measures that significantly distinguished between groups as predictors showed that these measures differentiated highly talented soccer players from amateur soccer players with 89% accuracy. Highly talented youth soccer players outperform youth amateur players on suppressing ongoing motor responses and on the ability to attain and maintain an alert state; both may be essential for success in soccer. PMID:24632735
Van Yperen, Nico W.
This study was conducted to examine psychological mechanisms underlying self-enhancing comparisons among 88 male major league professional soccer players. In line with other research, the results suggest that positive beliefs about oneself are more difficult to maintain with regard to unambiguous
Matteo Bonato, Luca Agnello, Letizia Galasso, Angela Montaruli, Eliana Roveda, Giampiero Merati, Antonio La Torre, Jacopo A. Vitale
Full Text Available The purpose of this study was to evaluate if the time of the day (8.00 a.m. vs 8.00 p.m. and chronotype could influence autonomic cardiac control in soccer players in relation to an acute session of high-intensity interval training. The morningness-eveningness questionnaire was administered to recruit Morning-type and Evening-type collegiate male soccer players. Therefore, 24 players (12 Morning-types and 12 Evening-types were randomly assigned, to either morning (n = 12; age 23 ± 3 years; height 1.75 ± 0.07 m; body mass 73 ± 10 kg; weekly training volume 8 2 hours, or evening (n = 12; age 21 ± 3 years; height 1.76 ± 0.05 m; body mass 75 ± 11 kg; weekly training volume 8 ± 3 hours training. Heart Rate Variability vagal and sympatho/vagal indices were calculated in time, frequency and complexity domains at rest, before, after 12 and 24 hours of high-intensity interval training. Before evening training session, a higher resting heart rate was observed which was determined by a marked parasympathetic withdrawal with a sympathetic predominance. Moreover, Evening-type subjects during morning training session, present a significant higher heart rate that corresponded to significant higher vagal indices with a significant lower parasympathetic tone that returned to the rest values after 24 hours of the cessation of high-intensity interval training exercise. On the contrary, Morning-type subjects did not reveal any significant differences with Evening-Type subjects during evening high-intensity interval training session. Stress response of high-intensity interval training is influenced by both the time of the day and by the chronotype. Understanding the Heart Rate Variability response to high-intensity interval training can be an additional important procedure for evaluating of cardiovascular recovery in soccer players. Moreover, these results suggest that an athlete’s chronotype should be taken into account when scheduling a high
Bonato, Matteo; Agnello, Luca; Galasso, Letizia; Montaruli, Angela; Roveda, Eliana; Merati, Giampiero; La Torre, Antonio; Vitale, Jacopo A
The purpose of this study was to evaluate if the time of the day (8.00 a.m. vs 8.00 p.m.) and chronotype could influence autonomic cardiac control in soccer players in relation to an acute session of high-intensity interval training. The morningness-eveningness questionnaire was administered to recruit Morning-type and Evening-type collegiate male soccer players. Therefore, 24 players (12 Morning-types and 12 Evening-types) were randomly assigned, to either morning (n = 12; age 23 ± 3 years; height 1.75 ± 0.07 m; body mass 73 ± 10 kg; weekly training volume 8 2 hours), or evening (n = 12; age 21 ± 3 years; height 1.76 ± 0.05 m; body mass 75 ± 11 kg; weekly training volume 8 ± 3 hours) training. Heart Rate Variability vagal and sympatho/vagal indices were calculated in time, frequency and complexity domains at rest, before, after 12 and 24 hours of high-intensity interval training. Before evening training session, a higher resting heart rate was observed which was determined by a marked parasympathetic withdrawal with a sympathetic predominance. Moreover, Evening-type subjects during morning training session, present a significant higher heart rate that corresponded to significant higher vagal indices with a significant lower parasympathetic tone that returned to the rest values after 24 hours of the cessation of high-intensity interval training exercise. On the contrary, Morning-type subjects did not reveal any significant differences with Evening-Type subjects during evening high-intensity interval training session. Stress response of high-intensity interval training is influenced by both the time of the day and by the chronotype. Understanding the Heart Rate Variability response to high-intensity interval training can be an additional important procedure for evaluating of cardiovascular recovery in soccer players. Moreover, these results suggest that an athlete's chronotype should be taken into account when scheduling a high-intensity interval training
Amalia Zorzou; Julia Zorzou; Athanasios Laios; Evangelos Bebetsos; Dimitris Kobodietas; Nikolaos Apostolidis
This present study investigated the psychological consuming behavior, the attitude and the motivations of professional soccer games spectators, aiming to increase the consumption of sports products...
Smith, Mitchell R.; Zeuwts, Linus; Lenoir, Matthieu; Hens, Nathalie; De Jong, Laura M. S.; Coutts, Aaron J.
This study aimed to investigate the impact of mental fatigue on soccer-specific decision-making. Twelve well-trained male soccer players performed a soccer-specific decision-making task on two occasions, separated by at least 72 h. The decision-making task was preceded in a randomised order by 30
Full Text Available Background. The anatomy and mechanical properties of the Crural Fascia (CF, the ubiquitous connective tissue of the posterior region of the leg, have recently been investigated. The most important findings are that (i the CF may suffer structural damage from indirect trauma, (ii structural changes of the CF may affect the biomechanics of tissues connected to it, causing myofascial pain syndromes, and (iii the CF is in anatomical continuity with the Achilles paratenon. Consistent with these points, the authors hypothesize that the onset of acute Achilles paratendinopathy may be related to histological and biomechanical changes of the CF. Case Presentation. A professional male football player suffered an isolated injury of the CF, interposed between the soleus and medial gastrocnemius (an atypical site of injury with structural connective integrity of the muscles. After participating in the first official match, two and a half months after the trauma, he has unexpectedly demonstrated the clinical picture of acute Achilles paratendinopathy in the previously injured limb. Conclusions. Analysis of this case suggests that the acute Achilles paratendinopathy may be a muscle injury complication from indirect trauma of the calf muscle, if a frank and extensive involvement of the CF were to be ascertained.
tunar, mert; Cetinkaya, Caner; gumus, hikmet; Gencoglu, Celal; Belgin UNAL; Kayatekin, Berkant Muammer
This study examined the validity and reliability of Soccer Specific Modified 1,5 Mile Run Test which isdeveloped for present research and applied in soccer field. Forty-eight male athletes were participated in the study(32 soccer, 5 basketball, 4 volleyball and 7 handball players). Participantsvisit the laboratory once. Height, weight, body fat percentage and maximaloxygen uptake were measured during laboratory session. In the field, SoccerSpecific Modified 1,5 Mile Run Test is performed two ...
Anderson, Liam; Orme, Patrick; Naughton, Robert J; Close, Graeme L; Milsom, Jordan; Rydings, David; O'Boyle, Andy; Di Michele, Rocco; Louis, Julien; Hambly, Catherine; Speakman, John Roger; Morgans, Ryland; Drust, Barry; Morton, James P
In an attempt to better identify and inform the energy requirements of elite soccer players, we quantified the energy expenditure (EE) of players from the English Premier League (n = 6) via the doubly labeled water method (DLW) over a 7-day in-season period. Energy intake (EI) was also assessed using food diaries, supported by the remote food photographic method and 24 hr recalls. The 7-day period consisted of 5 training days (TD) and 2 match days (MD). Although mean daily EI (3186 ± 367 kcals) was not different from (p > .05) daily EE (3566 ± 585 kcals), EI was greater (p players readily achieve current guidelines for daily protein and fat intake, data suggest that CHO intake on the day before and in recovery from match play was not in accordance with guidelines to promote muscle glycogen storage.
Vitale, Jacopo Antonino; Lombardi, Giovanni; Cavaleri, Luca; Graziani, Rosa; Schoenhuber, Herbert; Torre, Antonio La; Banfi, Giuseppe
Vitamin D is essential for the maintenance and promotion of musculoskeletal health, for the functioning of the immune, cardiovascular and reproductive systems, and its main action is to keep calcium and phosphate plasmatic physiological concentrations at intestinal, renal and bony level. Vitamin D affects several parameters related to physical performance too and a particularly high percentage of vitamin D insufficiency and deficiency in professional athletes has been observed. Several variables are able to impair the synthesis of 25(OH)D in athletes, specifically both genetic and environmental factors, but the most probable explanation for the deficient/insufficient vitamin D levels is the insufficient ultraviolet B light (UVB) exposure during winter. To confirm this, the existence of a circannual rhythm of vitamin D in professional soccer players, highlighting a peak in summer and lowest values in winter regardless the period of the season, has been documented. Nonetheless, from what we are aware of, no other study adopted a chronobiologic approach to better understand and describe the circannual variations of serum 25(OH)D in other sport disciplines. Therefore, we studied serum vitamin D in a cohort of top-level professional skiers, during a period of three consecutive competitive seasons (2015, 2016 and 2017), in order to evaluate, with a rhythmometric approach, the vitamin D behavior along the year. The study population was composed by 152 professional Italian alpine skiers of FISI (Winter Sport Italian Federation), 63 females and 89 males (mean age: 24.1 ± 3.2 years) and a total of 298 blood drawings were carried out to determine plasma 25(OH)D. Vitamin D data were compared between genders and then processed with the population mean cosinor tests to evaluate the presence of a circannual rhythm, both for female and male athletes. In total, 77 skiers (50.7%) showed, at least once during the three competitive seasons, an insufficient level of 25(OH)D and
Read, Paul J; Jimenez, Pablo; Oliver, Jon L; Lloyd, Rhodri S
Forty-one practitioners inclusive of physiotherapists, sports scientists and strength and conditioning coaches from the academies of elite soccer clubs in the United Kingdom completed an on-line questionnaire which examined their: (1) background information; (2) perceptions of injury occurrence and risk factors; (3) screening and return to play; and (4) approach to designing and delivering injury prevention programmes with a response rate of 55% (41/75). Contact injuries were the most common mechanism reported and players between 13-16 years of age were perceived to be at the greatest risk. Pertinent risk factors included: reduced lower limb and eccentric hamstring strength, proprioception, muscle imbalances, and under developed foundational movement skills. Joint range of motion, jump tests, the functional movement screen, overhead and single leg squats were the most utilised screening methods. Training modalities rated in order of importance included: resistance training, flexibility development, agility, plyometrics and balance training. Training frequency was most commonly once or twice per week, during warm-ups, independent sessions or a combination of both. Injury prevention strategies in this cohort appear to be logical; however, the classification of injury occurrence and application of screening tools to identify "at risk" players do not align with existing research. The frequency and type of training used may also be insufficient to elicit an appropriate stimulus to address pertinent risk factors based on current recommendations.
muscle injury detection. The use of 0.47 of Hcon/Qcon as a discriminate value resulted in significantly lower sensitivity when compared to 0.658 threshold (sensitivity of 16.7% vs. 91.7%, respectively; t = 6.125,p = 0.0133. Calculated values of specificity (when three different cut-off were applied were also significantly different. Threshold of 0.6 of Hcon/Qcon resulted with significantly lower specificity compared to 0.47 value (specificity of 46.9% vs. 94.5%, respectively; t = 153.0,p<0.0001, and significantly higher specificity when compared to 0.658 (specificity of 46.9% vs. 24.1%, respectively; t = 229.0, p<0.0001.The use of different cut-off values for Hcon/Qcon significantly affected the sensitivity and specificity of isokinetic testing. The interpretation of usefulness of isokinetic test as a screening tool in a group of male professional football players to predict hamstring injury occurrence within the next 12 months might be therefore significantly biased due to the different threshold values of Hcon/Qcon. Using one "normative" value as a cut-off (e.g. 0.47 or 0.60, or 0.658 to quantify soccer players (or not to the group with a higher risk of knee injury might result in biased outcomes due to the natural strength asymmetry that is observed within the group of soccer players.
Bogdanis, Gregory C; Papaspyrou, Aggeliki; Souglis, Athanasios G; Theos, Apostolos; Sotiropoulos, Aristomenis; Maridaki, Maria
This study compared the effects of two different half-squat training programs on the repeated-sprint ability of soccer players during the preseason. Twenty male professional soccer players were divided into 2 groups: One group (S-group) performed 4 sets of 5 repetitions with 90% of their 1-repetition maximum (1RM), and the other group (H-group) performed 4 sets of 12 repetitions with 70% of 1RM, 3 times per week for 6 weeks, in addition to their common preseason training program. Repeated-sprint ability was assessed before and after training by 10 × 6-second cycle ergometer sprints separated by 24 seconds of passive recovery. Maximal half-squat strength increased significantly in both groups (p repeated sprint ability. Therefore, resistance training with high loads may be preferable when the aim is to improve maximal strength and fatigue during sprinting in professional soccer players.
Conceição de Maria Pinheiro Barros
Full Text Available The Professional Executive Secretary has been occupying space increasingly evident in the labor market and organizational structure, both because of market demand, the needs of dynamism in the modern administration that demonstrates the growth of the reference to it. It has sought in his field vision and attitude of performance excellence with fulfilling its role with its own characteristics. This study aims to investigate the general challenges for the Executive Secretariat professional male in contemporary organizations. We defined the following objectives: to analyze the insertion of the male in the profession of Executive Secretary and identify the challenges faced by the Executive Secretary of the males to their development and professional growth. To this end, we performed a literature search, followed by a field survey. It is a qualitative research because data collected, and then make a qualitative analysis of results from selected literature. The survey was conducted in organizations from the public and private, state of Ceará. The sample was represented by professional male graduates in the executive secretariat at the Federal University of Ceará and working in the area. After analyzing the data it was concluded that despite the obstacles to be overcome, the tendency is that these opportunities work for the professional male grow, requiring that all actors in the field to seek gender equity in the profession.
Strahm, E; Emery, C; Saugy, M; Dvorak, J; Saudan, C
The determination of the carbon isotope ratio in androgen metabolites has been previously shown to be a reliable, direct method to detect testosterone misuse in the context of antidoping testing. Here, the variability in the 13C/12C ratios in urinary steroids in a widely heterogeneous cohort of professional soccer players residing in different countries (Argentina, Italy, Japan, South Africa, Switzerland and Uganda) is examined. Carbon isotope ratios of selected androgens in urine specimens were determined using gas chromatography/combustion/isotope ratio mass spectrometry (GC-C-IRMS). Urinary steroids in Italian and Swiss populations were found to be enriched in 13C relative to other groups, reflecting higher consumption of C3 plants in these two countries. Importantly, detection criteria based on the difference in the carbon isotope ratio of androsterone and pregnanediol for each population were found to be well below the established threshold value for positive cases. The results obtained with the tested diet groups highlight the importance of adapting the criteria if one wishes to increase the sensitivity of exogenous testosterone detection. In addition, confirmatory tests might be rendered more efficient by combining isotope ratio mass spectrometry with refined interpretation criteria for positivity and subject-based profiling of steroids.
Ersoy, Nesli; Ersoy, Gulgun; Kutlu, Mehmet
The purpose of the study is to determine and compare the hydration status with different methods and determine fluid intake, dehydration percentages and sweat rate of 26 young male soccer players (15 ± 1.2 years) before an important competition. More specifically, the study aims at validating the urine strip and advising the players to use it as an easy and practical method. Measurements of urine analysis were taken from the urine sample of the participants before breakfast and conducted for 3 consecutive days before the competition. Hydration status was assessed through analysis of urine color, urine specific gravity (USG) (laboratory, strip, refractometry), and osmolality. The players' dehydration percentages and sweat ratio were calculated. The average values for all samples were 3 ± 1 for color, and 1.021 ± 4 g/cm(3) for USG (laboratory), and 1.021 ± 3 g/cm(3) for USG (strip), and 1.021 ± 4 for USG (refractometry), and 903 ± 133 mOsm/kg for osmolality. USG (strip) was highly correlated with USG (laboratory), USG (refractometry) (r = 0.8; P hydration status of athletes must be taken into account more carefully under moderate and hot weather conditions. In addition, hydration methods were compatible with one another as measured in this study.
Lyle, Mark A; Valero-Cuevas, Francisco J; Gregor, Robert J; Powers, Christopher M
Controlling dynamic interactions between the lower limb and ground is important for skilled locomotion and may influence injury risk in athletes. It is well known that female athletes sustain anterior cruciate ligament (ACL) tears at higher rates than male athletes, and exhibit lower extremity biomechanics thought to increase injury risk during sport maneuvers. The purpose of this study was to examine whether lower extremity dexterity (LED)--the ability to dynamically control endpoint force magnitude and direction as quantified by compressing an unstable spring with the lower limb at submaximal forces--is a potential contributing factor to the "at-risk" movement behavior exhibited by female athletes. We tested this hypothesis by comparing LED-test performance and single-limb drop jump biomechanics between 14 female and 14 male high school soccer players. We found that female athletes exhibited reduced LED-test performance (p=0.001) and higher limb stiffness during landing (p=0.008) calculated on average within 51 ms of foot contact. Females also exhibited higher coactivation at the ankle (p=0.001) and knee (p=0.02) before landing. No sex differences in sagittal plane joint angles and center of mass velocity at foot contact were observed. Collectively, our results raise the possibility that the higher leg stiffness observed in females during landing is an anticipatory behavior due in part to reduced lower extremity dexterity. The reduced lower extremity dexterity and compensatory stiffening strategy may contribute to the heightened risk of ACL injury in this population. © 2013 Published by Elsevier Ltd.
Sergej M. Ostojic
Full Text Available The aim of this study was to examine the effects of a carbohydrate-electrolyte drink on specific soccer tests and performance. Twenty-two professional male soccer players volunteered to participate in the study. The players were allocated to two assigned trials ingesting carbohydrate-electrolyte drink (7% carbohydrates, sodium 24 mmol.l-1, chloride 12 mmol.l-1, potassium 3 mmol.l-1 or placebo during a 90 min on-field soccer match. The trials were matched for subjects' age, weight, height and maximal oxygen uptake. Immediately after the match, players completed four soccer-specific skill tests. Blood glucose concentration [mean (SD] was higher at the end of the match-play in the carbohydrate-electrolyte trial than in the placebo trial (4.4 (0.3 vs. 4.0 (0.3 mmol.l-1, P < 0.05. Subjects in the carbohydrate-electrolyte trial finished the specific dribble test faster in comparison with subjects in the placebo trial (12.9 (0.4 vs. 13.6 (0.5 s, P < 0.05. Ratings of the precision test were higher in the carbohydrate-electrolyte trial as compared to the placebo trial (17.2 (4.8 vs. 15.1 (5.2, P < 0.05 but there were no differences in coordination test and power test results between trials. The main finding of the present study indicates that supplementation with carbohydrate-electrolyte solution improved soccer-specific skill performance and recovery after an on-field soccer match compared with ingestion of placebo. This suggests that soccer players should consume carbohydrate-electrolyte fluid throughout a game to help prevent deterioration in specific skill performance
Diment, Gregory Michael
of the program, (b) education and designing soccer drills, and (c) delivery of the drills on the soccer pitch. The program was well received by clubs, coaches, and players. With regards to project aims, the intervention was generally considered a success. Coaches reported that the drill-based nature...... of the program was practical and relevant to young players’ development of psychological skills and many players and coaches have continued working with this approach. However, success varied across the nine clubs and was influenced by factors such as the clubs’ willingness and capacity to adopt new concepts...... by creating a series of drillbased sessions to train psychological skills, and educate coaches about how to implement and integrate PST as a natural part of daily training. The program was delivered to the youth academies in nine Danish professional soccer clubs and consisted of three phases: (a) planning...
Diment, Gregory Michael
In the past decade mental toughness has been discussed as a significant factor in performance in elite sport. Few studies have explored mental toughness from a behavioral perspective, and no comprehensive lists of mental toughness behaviors have been developed. The aim of the study was to produce...... a systematic observation checklist of mental toughness behavior in professional soccer. Consistent with existing studies, the results created a systematic observation instrument containing 15 mental toughness behaviors. Practical implications include goal-setting, game analysis and self-modeling interventions...
Professionalising the early childhood workforce in terms of improving pay and conditions of work and employing male workers can be seen as independent trends: there is no necessary relationship between the two. However, when the definition of professionalism is extended to include the scope and quality of practice, the experiences and views of…
Imai, Atsushi; Kaneoka, Koji; Okubo, Yu; Shiraki, Hitoshi
Trunk exercises, such as trunk stabilization exercises (SE) and conventional trunk exercises (CE), are performed to improve static or dynamic balance. Recently, trunk exercises have also been often used as part of warm-up programs. A few studies have demonstrated the immediate effects of SE and CE on static balance. However, immediate effects on dynamic balance are not yet known. Therefore, the purpose of this study was to compare the immediate effect of SE with that of CE on the Star Excursion Balance Test (SEBT). Eleven adolescent male soccer players (17.9 ± 0.3 years, 168.5 ± 5.4 cm, and 60.1 ± 5.1 kg) participated in this study. A crossover design was used, and each participant completed three kinds of testing sessions: SE, CE, and non-exercise (NE). Experiments took place for three weeks with three testing sessions, and a 1-week interval was provided between different conditions. Each testing session consisted of three steps: pretest, intervention, and posttest. To assess dynamic balance, the SEBT score in the anterior, posteromedial, and posterolateral directions was measured before and 5 minutes after each intervention program. The data of reach distance were normalized with the leg length to exclude the influence of the leg length on the analysis. The SEBT composite score was significantly improved after the SE (p 0.05). Furthermore, in the SE condition, SEBT scores of the posterolateral and posteromedial directions were significantly improved at the posttest, compared with those at the pretest (p balance. 3b.
Lameiras, João; Almeida, Pedro L; Garcia-Mas, Alexandre
In team sports, athletes' goals may focus on the task (enhancing performance, developing better skills, etc.) or on ego (being better than the others, achieving superiority, etc.). This study investigated the relationships between athletes' goal orientation and their tendency to cooperate with teammates and coaches. 158 professional men (M age = 24.1 yr., SD = 4.6) who played on various sport teams participated in this study. Goal orientation was measured with the Portuguese version of the Task and Ego Orientation in Sport Questionnaire, and cooperation was measured with the Questionário de Cooperação Desportiva. Cooperation was positively correlated with task orientation, and negatively correlated with ego orientation. Overall, the findings support that in sports, directing the players' focus on task may promote prosocial behavior.
McAleer, Stephen S; Lippie, Ed; Norman, Darcy; Riepenhof, Helge
Study Design Case series. Background Pubic bone stress (PBS) is a common acute or chronic response of the pelvis in sports where sprinting, kicking, twisting, and cutting are the dominant movements. There are few nonoperative rehabilitation strategies for the condition reported in the literature, and the outcome of conservative treatment has not been documented. Case Description Five professional and academy soccer players complaining of pubic symphysis pain, confirmed as PBS on magnetic resonance imaging and objective assessment, were treated with a nonoperative rehabilitation program that featured functional and clinical objective markers as progression criteria. Interventions in the acute phase included pharmacological and physical therapeutic modalities to reduce pain initially. Rehabilitation management focused on improving range of motion at the hips and thorax, adductor strengthening, trunk and lumbopelvic stability, gym-based strength training, and field-based rehabilitation and conditioning. Clinical follow-up was performed at least 8 months following return to play. Outcomes All players demonstrated reduced or resolved pain, increased adductor squeeze strength, and return to pain-free training and match play. Return-to-training time averaged 40.6 days (range, 30-60 days) and return to play averaged 49.4 days (range, 38-72 days) within the 5 players. At final follow-up (mean, 29.6 months; range, 16-33 months), there had been no recurrences. Discussion This report of 5 cases suggests that a nonoperative protocol, using clinical and functional progression criteria, may be successful in rehabilitating athletes with PBS for return to sport within 11 weeks. Level of Evidence Therapy, level 4. J Orthop Sports Phys Ther 2017;47(9):683-690. Epub 3 Aug 2017. doi:10.2519/jospt.2017.7314.
Giagazoglou, Paraskevi; Katis, Athanasios; Kellis, Eleftherios; Natsikas, Christos
The purpose of the current study was to examine the kinematic differences during instep soccer kicks between players who were blind and sighted controls. Eleven male soccer players who were blind and nine male sighted performed instep kicks under static and dynamic conditions. The results indicated significantly higher (p less than 0.05) ball…
Gouttebarge, Vincent; Aoki, Haruhito; Ekstrand, Jan; Verhagen, Evert A L M; Kerkhoffs, Gino M M J
To explore the associations of severe musculoskeletal injuries (joint and muscles) and surgeries with symptoms of common mental disorders (distress, anxiety/depression, sleeping disturbance, adverse alcohol behaviour , smoking, adverse nutrition behaviour) among male European professional footballers. Cross-sectional analyses were conducted on electronic questionnaires completed by professional footballers recruited from the national players' unions of Finland, France, Norway, Spain or Sweden. The number of severe (time loss of more than 28 days) musculoskeletal injuries (total, joint, muscle) and surgeries during a professional football career was examined through four questions, while symptoms of common mental disorders were evaluated through validated scales. A total of 540 professional footballers (mean age of 27 years; 54 % playing in the highest leagues) participated in the study. Sixty-eight per cent of the participants had already incurred one or more severe joint injuries and 60 % one or more severe muscle injuries. Prevalence of symptoms of common mental disorders ranged from 3 % for smoking to 37 % for anxiety/depression and 58 % for adverse nutrition behaviour. The number of severe musculoskeletal injuries during a football career was positively correlated with distress, anxiety and sleeping disturbance, while the number of surgeries was correlated with adverse alcohol behaviour and smoking. Professional footballers who had sustained one or more severe musculoskeletal injuries during their career were two to nearly four times more likely to report symptoms of common mental disorders than professional footballers who had not suffered from severe musculoskeletal injuries. It can be concluded that the number of severe musculoskeletal injuries and surgeries during a career is positively correlated and associated with symptoms of common mental disorders among male European professional footballers. This study emphasises the importance of applying a
Koc, Baris B; Somorjai, Nicolaas; P M Kiesouw, Egid; Vanderdood, Kurt; Meesters-Caberg, Marleen; Draijer, Frits W; Jansen, Edwin J P
A Morel-Lavallée lesion is a post-traumatic closed degloving injury of soft tissue. The lesion is due to a shearing trauma with separation of subcutaneous tissue from underlying fascia. When conservative treatment fails, surgical treatment is imperative. Commonly, open drainage and debridement is performed. This case report describes a Morel-Lavallée lesion of the knee in a professional soccer player who was successfully treated with endoscopic debridement and fibrin glue injection after failure of conservative management. This method achieves the goal of an open surgical debridement without exposing patients to an increased morbidity. Copyright © 2016. Published by Elsevier B.V.
McGovern, Andrew; Dude, Christopher; Munkley, Daniel; Martin, Thomas; Wallace, David; Feinn, Richard; Dione, Donald; Garbalosa, Juan C
Despite the recent emphasis on injury prevention, anterior cruciate ligament (ACL) injury rates remain high. This study aimed to ascertain the effects of prolonged activity on lower limb kinematics during a self-selected cutting maneuver. Angular kinematics were recorded during an agility test performed until the completion time was greater than the mean plus one SD of baseline trials. Cut type was identified and the hip and knee angles at 33 ms post heel strike were determined. A linear mixed effects model assessed the effects of cut type, gender, and activity status on the hip and knee angles. Males performed sidestep cuts more frequently than females. Females increased the incidence of sidestep cuts after prolonged activity. At the hip, a gender-cut type interaction existed for the transverse (p=0.001) and sagittal (p=0.11) planes. Females showed more internal rotation during sidestep and more external rotation and less flexion during crossover cuts. For the frontal plane, a gender-activity status interaction (p = 0.032) was due to no change within females but greater hip adduction during prolonged activity within males. With prolonged activity, both genders displayed less hip (p=0.29) and knee (p=0.009) flexion and more knee (p=0.001) adduction. Females displayed less hip and knee flexion than men (p=0.001). Sidestep may be more risky than crossover cuts. Both genders place themselves in at-risk postures with prolonged activity due to less hip and knee flexion. Copyright © 2015 Elsevier B.V. All rights reserved.
Hughes, T; Sergeant, J C; Parkes, M; Callaghan, M
To identify prognostic factors and models for spinal and lower extremity injuries in adult professional/elite football players from medical screening and training load monitoring processes. The MEDLINE, AMED, EMBASE, CINAHL Plus, SPORTDiscus electronic bibliographic databases and the Cochrane Database of Systematic Reviews were searched from inception to July 2016. Searches were limited to original research, published in peer reviewed journals of any language. The Quality in Prognostic Studies (QUIPS) tool was used for appraisal and the modified GRADE approach was used for synthesis. Prospective and retrospective cohort study designs of spinal and lower extremity injury incidence were found from populations of adult professional/elite football players, between 16 and 40 years. Non-football or mixed sports were excluded. 858 manuscripts were identified. Removing duplications left 551 studies, which were screened for eligibility by title and abstract. Of these, 531 studies were not eligible and were excluded. The full text of the remaining 20 studies were obtained; a further 10 studies were excluded. 10 studies were included for appraisal and analysis, for 3344 participants. Due to the paucity and heterogeneity of the literature, and shortcomings in methodology and reporting, the evidence is of very low or low quality and therefore cannot be deemed robust enough to suggest conclusive prognostic factors for all lower limb musculoskeletal injury outcomes identified. No studies were identified that examined spinal injury outcomes or prognostic models.
Torreblanca-Martinez, Víctor; Otero-Saborido, Fernando M; Gonzalez-Jurado, José A
The purpose was to study the effects of muscle fatigue induced by countermovement jumps (CMJ) on instep kick foot velocity in young male soccer players. Fifteen under-18 soccer players from a professional club performed maximal velocity instep kicks before and after a fatigue protocol that consisted of continuous CMJ. Foot velocity at impact without fatigue, foot velocity at impact with fatigue, CMJ height without fatigue, maximum jump height in fatigue test, and CMJ height change in fatigue test on a dynamometric platform were measured. There was a significant difference between jump height with and without fatigue (P = .00; ES = 0.8), but there were no significant differences between kicking with fatigue and without fatigue (P = .580, ES = 0.10). In conclusion, although the protocol was intense enough to generate fatigue in the muscles involved in CMJ, there were no significant differences in kicking velocity under fatigue conditions with respect to kicking without fatigue in the soccer players studied.
Rostgaard Andersen, Thomas; Schmidt, Jakob Friis; Pedersen, Mogens Theisen
The effects of 52 weeks of soccer or resistance training were investigated in untrained elderly men. The subjects aged 68.1±2.1 yrs were randomised into a soccer (SG; n = 9), a resistance (RG; n = 9) and a control group (CG; n = 8). The subjects in SG and RG, respectively, trained 1.7±0.3 and 1...... expression decreased by 38% (ptraining reduces BMI and improves anti-oxidative capacity, while long-term resistance training impacts muscle protein enzyme expression and increases lean body mass in elderly men....
Fanchini, M; Schena, F; Castagna, C; Petruolo, A; Combi, F; McCall, A; Impellizzeri, M
The aim of this study was to assess the external responsiveness, construct validity and internal responsiveness of the Yo-Yo Intermittent Recovery test level 1 and its sub-maximal version in semi-professional players. Tests and friendly matches were performed during the preseason and regular season. The distance covered above 15 km·h(-1) was considered as an indicator of the physical match performance. Construct validity and external responsiveness were examined by correlations between test and physical match performance (preseason and regular season) and training-induced changes. Internal responsiveness was determined as Cohen's effect size, standardized response mean and signal-to-noise ratio. The physical match performance increased after training (34.8%). The Yo-Yo Intermittent Recovery test level 1 improved after training (40.2%), showed longitudinal (r=0.69) and construct validity (r=0.73 and 0.59, preseason and regular season) and had higher internal responsiveness compared to its sub-maximal version. The heart rate at the 6(th) minute in the sub-maximal version did not show longitudinal (r=-0.38) and construct validity (r=0.01 and -0.06, preseason and regular season) and did not significantly change after training (-0.3%). The rate of perceived exertion decreased in the sub-maximal version (- 29.8%). In conclusion, the Yo-Yo Intermittent Recovery test level 1 is valid and responsive, while the validity of its sub-maximal version is questionable. © Georg Thieme Verlag KG Stuttgart · New York.
Al Attar, Wesam Saleh A; Soomro, Najeebullah; Pappas, Evangelos; Sinclair, Peter J; Sanders, Ross H
Does adding a post-training Fédération Internationale de Football Association (FIFA) 11+ exercise program to the pre-training FIFA 11+ injury prevention program reduce injury rates among male amateur soccer players? Cluster-randomised, controlled trial with concealed allocation. Twenty-one teams of male amateur soccer players aged 14 to 35 years were randomly assigned to the experimental group (n=10 teams, 160 players) or the control group (n=11 teams, 184 players). Both groups performed pre-training FIFA 11+ exercises for 20minutes. The experimental group also performed post-training FIFA 11+ exercises for 10minutes. The primary outcomes measures were incidence of overall injury, incidence of initial and recurrent injury, and injury severity. The secondary outcome measure was compliance to the experimental intervention (pre and post FIFA 11+ program) and the control intervention (pre FIFA 11+ program). During one season, 26 injuries (team mean=0.081 injuries/1000 exposure hours, SD=0.064) were reported in the experimental group, and 82 injuries were reported in the control group (team mean=0.324 injuries/1000hours, SD=0.084). Generalised Estimating Equations were applied with an intention-to-treat analysis. The pre and post FIFA 11+ program reduced the total number of injuries (χ 2 (1)=11.549, p=0.001) and the incidence of initial injury (χ 2 (2)=8.987, p=0.003) significantly more than the pre FIFA 11+ program alone. However, the odds of suffering a recurrent injury were not different between the two groups (χ 2 (1)=2.350, p=0.125). Moreover, the severity level of injuries was not dependent upon whether or not the pre and post FIFA 11+ program was implemented (χ 2 (1)=0.016, p=0.898). Implementation of the FIFA 11+ program pre-training and post-training reduced overall injury rates in male amateur soccer players more than the pre FIFA 11+ program alone. ACTRN12615001206516. [Al Attar WSA, Soomro N, Pappas E, Sinclair PJ, Sanders RH (2017) Adding a post
Corboz, Julienne; Flood, Michael; Dyson, Sue
Programs aimed at preventing violence against women have increasingly adopted bystander approaches, yet large gaps remain in our knowledge about what drives bystanders to act or not, particularly in settings where there is an increased risk of violence against women occurring. This article contributes to this gap by examining data from research with professional male athletes from the Australian Football League. Drawing from a mixed methods approach, including a survey and interviews with football players, we outline some of the challenges to bystander intervention faced by professional athletes and discuss some of the possible similarities and differences between these and other groups of men. © The Author(s) 2015.
Ric, Angel; Torrents, Carlota; Gonçalves, Bruno; Sampaio, Jaime; Hristovski, Robert
This study aimed to identify the tactical patterns and the timescales of variables during a soccer match, allowing understanding the multilevel organization of tactical behaviors, and to determine the similarity of patterns performed by different groups of teammates during the first and second halves. Positional data from 20 professional male soccer players from the same team were collected using high frequency global positioning systems (5 Hz). Twenty-nine categories of tactical behaviors were determined from eight positioning-derived variables creating multivariate binary (Boolean) time-series matrices. Hierarchical principal component analysis (PCA) was used to identify the multilevel structure of tactical behaviors. The sequential reduction of each set level of principal components revealed a sole principal component as the slowest collective variable, forming the global basin of attraction of tactical patterns during each half of the match. In addition, the mean dwell time of each positioning-derived variable helped to understand the multilevel organization of collective tactical behavior during a soccer match. This approach warrants further investigations to analyze the influence of task constraints on the emergence of tactical behavior. Furthermore, PCA can help coaches to design representative training tasks according to those tactical patterns captured during match competitions and to compare them depending on situational variables.
Full Text Available This study aimed to identify the tactical patterns and the timescales of variables during a soccer match, allowing understanding the multilevel organization of tactical behaviors, and to determine the similarity of patterns performed by different groups of teammates during the first and second halves. Positional data from twenty professional male soccer players from the same team were collected using high frequency global positioning systems (5Hz. Twenty-nine categories of tactical behaviors were determined from eight positioning-derived variables creating multivariate binary (Boolean time-series matrices. Hierarchical principal component analysis was used to identify the multilevel structure of tactical behaviors. The sequential reduction of each set level of principal components revealed a sole principal component as the slowest collective variable, forming the global basin of attraction of tactical patterns during each half of the match. In addition, the mean dwell time of each positioning-derived variable helped to understand the multilevel organization of collective tactical behavior during a soccer match. This approach warrants further investigations to analyze the influence of task constraints on the emergence of tactical behavior. Furthermore, principal component analysis can help coaches to design representative training tasks according to those tactical patterns captured during match competitions and to compare them depending on situational variables.
The purpose of this study was to investigate the relationship between the isokinetic quadriceps and hamstring strength and, sprinting ability, agility and vertical jump performance in male volleyball players. Twenty professional male volleyball players (average age 24.5±1.1 years; mean body height 186.5±5.02 cm; mean body mass 75.34±8.39 kg) participated in this study voluntarily. For each player, isokinetic concentric muscle strength tests were performed at 60°/s and 300°/s, jump performance...
This study focused on coping strategies used by soccer (football) players by exploring the role of the environment, ethnicity and culture in players' response to stressful situations. An interpretive-qualitative research methodology was applied with a sample of 33 professional soccer players. The subjects were representative ...
Van de Hoef, S; Huisstede, B M A; Brink, M S; de Vries, N; Goedhart, E A; Backx, F J G
Hamstring injuries are the most common muscle injury in amateur and professional soccer. Most hamstring injuries occur in the late swing phase, when the hamstring undergoes a stretch-shortening cycle and the hamstring does a significant amount of eccentric work. The incidence of these injuries has not decreased despite there being effective injury prevention programmes focusing on improving eccentric hamstring strength. As this might be because of poor compliance, a more functional injury prevention exercise programme that focuses on the stretch-shortening cycle might facilitate compliance. In this study, a bounding exercise programme consisting of functional plyometric exercises is being evaluated. A cluster-randomized controlled trial (RCT). Male amateur soccer teams (players aged 18-45 years) have been randomly allocated to intervention and control groups. Both groups are continuing regular soccer training and the intervention group is additionally performing a 12-week bounding exercise programme (BEP), consisting of a gradual build up and maintenance programme for the entire soccer season. The primary outcome is hamstring injury incidence. Secondary outcome is compliance with the BEP during the soccer season and 3 months thereafter. Despite effective hamstring injury prevention programmes, the incidence of these injuries remains high in soccer. As poor compliance with these programmes may be an issue, a new plyometric exercise programme may encourage long-term compliance and is expected to enhance sprinting and jumping performance besides preventing hamstring injuries. NTR6129 . Retrospectively registered on 1 November 2016.
Devlin, Brooke L; Kingsley, Michael; Leveritt, Michael D; Belski, Regina
Devlin, BL, Kingsley, M, Leveritt, MD, and Belski, R. Seasonal changes in soccer players' body composition and dietary intake practices. J Strength Cond Res 31(12): 3319-3326, 2017-The aims of this study were 2-fold: to determine seasonal changes in dietary intake and body composition in elite soccer players and to evaluate the influence of self-determined individual body composition goals on dietary intake and body composition. This longitudinal, observational study assessed body composition (total mass, fat-free soft tissue mass, and fat mass) using dual-energy x-ray absorptiometry and dietary intake (energy and macronutrients) via multiple-pass 24-hour recalls, at 4 time points over a competitive season in elite soccer players from one professional club in the Australian A-League competition. Self-reported body composition goals were also recorded. Eighteen elite male soccer players took part (25 ± 5 years, 180.5 ± 7.4 cm, 75.6 ± 6.5 kg). Majority (≥67%) reported the goal to maintain weight. Fat-free soft tissue mass increased from the start of preseason (55,278 ± 5,475 g) to the start of competitive season (56,784 ± 5,168 g; p composition goals did not strongly influence dietary intake practices or changes in body composition. This study has demonstrated that body composition changes over the course of a soccer season are subtle in elite soccer players despite relatively low self-reported intake of energy and carbohydrate.
Full Text Available This study aims to investigate professional readiness of a selected group of male and female experts in Iranian sports organizations. It is a descriptive study with an applied objective. The statistical population of the study includes the entire selected male and female experts (406 experts of Iranian sports organizations among which 352 cases cooperated with the researchers and therefore were selected as research sample. Measurement tool is the professional readiness assessment standard questionnaire (Aliabadi, 2014; the validity and reliability of this questionnaire have been approved by sport experts. The descriptive and inferential statistics including KS- and T-test was used to analyze the data. The results indicate that there is no significant difference between male and female experts in sports organizations regarding mental readiness and its components (motivation, commitment, confidence; but there is a significant difference at 0.01 level between them with regard to work readiness and its components (skill, knowledge, experience. Moreover, based on the average of work/technical readiness components, male experts are better than female experts.
Lemmink, K.A.P.M.; Visscher, C.
The influence of intermittent exercise on a choice-response time task was investigated. Two groups of 8 male soccer players (M age 20.9, SD=2.0) participated. They spent 4.4 (SD= 1.3) weekly hours on soccer training and had been playing soccer for 13 (SD=3.3) years. Multiple-choice reaction speed
Full Text Available Many sports (for instance soccer are stereotypically perceived as a male activity. Even so, more and more women decide to become competitive athletes. Since the theory of sport requires comprehensive explanations and the practice of sport needs clear guidelines, interdisciplinary studies into the nature of sport, including its psychological aspects, are necessary. Analysing the psychological profile of female soccer players, particularly those who are about to become professional athletes, can provide many interesting insights into the specific character of female youth sport and show where improvements can be made in athletic training programmes (especially in mental training. It is therefore important to study psychological gender that determines social behaviours and to analyse female athletes’ emotional intelligence. Emotional intelligence is defined as a set of emotional competencies that determine the effectiveness of human behaviours. Psychological gender and emotional intelligence have a significant effect on human adaptability and the efficiency of psychosocial functioning. This research was undertaken with the dual purpose of identifying the psychological gender and emotional intelligence of female soccer players. It involved 54 secondary-school girls, some of whom attended a sports class and others played on the Polish national team. The following tools were used to carry out the research: the Gender Assessment Inventory (IPP [This and the other acronyms derive from the Polish language]-developed by Kuczyńska and the Emotional Intelligence Questionnaire (INTE; created by Jaworowska and Matczak. As shown by the analysis of the results, most female soccer players in the study were androgynous and the level of their emotional intelligence was significantly higher than in other participants. This also seems to point to their significantly greater adaptability. At the same time, the level of emotional intelligence in many players was
Rutkowska, Katarzyna; Bergier, Józef
Many sports (for instance soccer) are stereotypically perceived as a male activity. Even so, more and more women decide to become competitive athletes. Since the theory of sport requires comprehensive explanations and the practice of sport needs clear guidelines, interdisciplinary studies into the nature of sport, including its psychological aspects, are necessary. Analysing the psychological profile of female soccer players, particularly those who are about to become professional athletes, can provide many interesting insights into the specific character of female youth sport and show where improvements can be made in athletic training programmes (especially in mental training). It is therefore important to study psychological gender that determines social behaviours and to analyse female athletes’ emotional intelligence. Emotional intelligence is defined as a set of emotional competencies that determine the effectiveness of human behaviours. Psychological gender and emotional intelligence have a significant effect on human adaptability and the efficiency of psychosocial functioning. This research was undertaken with the dual purpose of identifying the psychological gender and emotional intelligence of female soccer players. It involved 54 secondary-school girls, some of whom attended a sports class and others played on the Polish national team. The following tools were used to carry out the research: the Gender Assessment Inventory (IPP [This and the other acronyms derive from the Polish language]-developed by Kuczyńska) and the Emotional Intelligence Questionnaire (INTE; created by Jaworowska and Matczak). As shown by the analysis of the results, most female soccer players in the study were androgynous and the level of their emotional intelligence was significantly higher than in other participants. This also seems to point to their significantly greater adaptability. At the same time, the level of emotional intelligence in many players was average or low
Rutkowska, Katarzyna; Bergier, Józef
Many sports (for instance soccer) are stereotypically perceived as a male activity. Even so, more and more women decide to become competitive athletes. Since the theory of sport requires comprehensive explanations and the practice of sport needs clear guidelines, interdisciplinary studies into the nature of sport, including its psychological aspects, are necessary. Analysing the psychological profile of female soccer players, particularly those who are about to become professional athletes, can provide many interesting insights into the specific character of female youth sport and show where improvements can be made in athletic training programmes (especially in mental training). It is therefore important to study psychological gender that determines social behaviours and to analyse female athletes' emotional intelligence. Emotional intelligence is defined as a set of emotional competencies that determine the effectiveness of human behaviours. Psychological gender and emotional intelligence have a significant effect on human adaptability and the efficiency of psychosocial functioning. This research was undertaken with the dual purpose of identifying the psychological gender and emotional intelligence of female soccer players. It involved 54 secondary-school girls, some of whom attended a sports class and others played on the Polish national team. The following tools were used to carry out the research: the Gender Assessment Inventory (IPP [This and the other acronyms derive from the Polish language]-developed by Kuczyńska) and the Emotional Intelligence Questionnaire (INTE; created by Jaworowska and Matczak). As shown by the analysis of the results, most female soccer players in the study were androgynous and the level of their emotional intelligence was significantly higher than in other participants. This also seems to point to their significantly greater adaptability. At the same time, the level of emotional intelligence in many players was average or low
Full Text Available The study aimed to evaluate the test-retest reliability of a newly developed 356 Soccer Shooting Test (356-SST, and the discriminative ability of this test with respect to the soccer players' proficiency level and leg dominance. Sixty-six male soccer players, divided into three groups based on their proficiency level (amateur, n = 24; novice semi-professional, n = 18; and experienced semi-professional players, n = 24, performed 10 kicks following a two-step run up. Forty-eight of them repeated the test on a separate day. The following shooting variables were derived: ball velocity (BV; measured via radar gun, shooting accuracy (SA; average distance from the ball-entry point to the goal centre, and shooting quality (SQ; shooting accuracy divided by the time elapsed from hitting the ball to the point of entry. No systematic bias was evident in the selected shooting variables (SA: 1.98±0.65 vs. 2.00±0.63 m; BV: 24.6±2.3 vs. 24.5±1.9 m s-1; SQ: 2.92±1.0 vs. 2.93±1.0 m s-1; all p>0.05. The intra-class correlation coefficients were high (ICC = 0.70-0.88, and the coefficients of variation were low (CV = 5.3-5.4%. Finally, all three 356-SST variables identify, with adequate sensitivity, differences in soccer shooting ability with respect to the players' proficiency and leg dominance. The results suggest that the 356-SST is a reliable and sensitive test of specific shooting ability in men's soccer. Future studies should test the validity of these findings in a fatigued state, as well as in other populations.
Background: Sport is a compulsory activity in schools in South Africa. Female learners participating in soccer are more vulnerable to injuries than males. Objective: This study determined the epidemiology of injuries in female high school soccer players. Methods: A cross sectional survey captured the epidemiology of ...
Kemper, G. L. J.; van der Sluis, A.; Brink, M. S.; Visscher, C.; Frencken, W. G. P.; Elferink-Gemser, M. T.
The aim of the study was to investigate whether an increased risk of injury occurrence can be determined through frequent anthropometric measurements in elite-standard youth soccer players. Over the course of one season, we followed 101 male elite-standard youth soccer players between 11 and 19
Gray, C.M.; Hunt, K.; Mutrie, N.; Anderson, A.S.; Treweek, S.; Wyke, S.
BACKGROUND: The prevalence of male obesity is increasing, but men are less likely than women to attend existing weight management programmes. We have taken a novel approach to reducing perceived barriers to weight loss for men by using professional football (soccer) clubs to encourage participation
Prognostic factors for specific lower extremity and spinal musculoskeletal injuries identified through medical screening and training load monitoring in professional football (soccer): a systematic review.
Hughes, Tom; Sergeant, Jamie C; Parkes, Matthew J; Callaghan, Michael J
Medical screening and load monitoring procedures are commonly used in professional football to assess factors perceived to be associated with injury. To identify prognostic factors (PFs) and models for lower extremity and spinal musculoskeletal injuries in professional/elite football players from medical screening and training load monitoring processes. The MEDLINE, AMED, EMBASE, CINAHL Plus, SPORTDiscus and PubMed electronic bibliographic databases were searched (from inception to January 2017). Prospective and retrospective cohort studies of lower extremity and spinal musculoskeletal injury incidence in professional/elite football players aged between 16 and 40 years were included. The Quality in Prognostic Studies appraisal tool and the modified Grading of Recommendations Assessment, Development and Evaluation synthesis approach was used to assess the quality of the evidence. Fourteen studies were included. 16 specific lower extremity injury outcomes were identified. No spinal injury outcomes were identified. Meta-analysis was not possible due to heterogeneity and study quality. All evidence related to PFs and specific lower extremity injury outcomes was of very low to low quality. On the few occasions where multiple studies could be used to compare PFs and outcomes, only two factors demonstrated consensus. A history of previous hamstring injuries (HSI) and increasing age may be prognostic for future HSI in male players. The assumed ability of medical screening tests to predict specific musculoskeletal injuries is not supported by the current evidence. Screening procedures should currently be considered as benchmarks of function or performance only. The prognostic value of load monitoring modalities is unknown.
Dr.Gopal Chandra Saha; Dr. Hiralal Adhikari
The purpose of the study was to investigate the effect of specific soccer training on General Soccer ability (volleying Skill) by using Mcdonald Soccer Test of high fit tribal soccer players. ninety, high fit tribal Soccer players out of two hundred and seventy, 9th and 10th grade school level tribal Soccer players from Ergoda School parihati of paschim Medinipur, District of West Bengal were randomly selected as the tribal subjects for this study. To ascertain the high fit tribal Soccer play...
Dr. M S Nagarajan
Full Text Available Background: Football is the world's most popular sport. There are over 240 million registered players worldwide and many more recreational footballers. The knee is a complex joint with many components making it vulnerable to a variety of injuries. The study has investigated the effect of knee proprioception error on injured and uninjured male professional footballers. Methods: This was a cross sectional comparative study with hundred and six (106 male professional footballers were selected for the study as per the selection criteria. Hundred and eighteen injured and ninety four uninjured knee samples were analysed for this study. Photographic analysis method was used to evaluate proprioception error at inner, middle and outer range of knee joint. Proprioception error of knee joint was measured at inner range, middle range and outer range for injured and uninjured groups. Data analysis found that there is significant difference in proprioception error between the groups. Result: Comparative study was performed using independent t’ test for proprioception error between knee injured and uninjured groups. P<0.05 were considered as significant difference in effect for this study. The means of knee injured and uninjured groups were 6.08 and 5.55 respectively with t’ value 2.21 and degree of freedom 634. The study found that proprioception error has significant difference in effect on knee injury, with P< 0.03*. Conclusion: The study concluded that proprioception error was varied between knee injured and uninjured groups. Proprioception error of knee joint was more among injured male professional footballers compared to the uninjured footballers.
Huijgen, B. C. H.; Elferink-Gemser, M. T.; Post, W. J.; Visscher, C.
The purpose of this study was to investigate the relationship between the development of the technical skill dribbling during ages 14-18 and adulthood playing level. The results gained insight in the required level of the technical skill dribbling during adolescence to be capable of becoming a
Harper, Liam D; Clifford, Tom; Briggs, Marc A; McNamee, Ged; West, Daniel J; Stevenson, Emma; Russell, Mark
This study investigated the changes in indices of acid-base balance during 120 minutes of simulated soccer match play that included a 30 minute extra-time (ET) period. Eight English Premier League academy soccer players participated in a simulated soccer match that required varying intensities of intermittent exercise including 15-m sprints and soccer dribbling throughout. Blood samples were obtained before (i.e., baseline and pre-exercise) and throughout exercise (i.e., 15, 30, 45, 60, 75, 90, 105, and 120 minutes), and at half time. Sprint speeds over 15 m reduced in ET compared to the first half (-0.39 ± 0.37 m·s, -7 ± 6%, p = 0.021) but not the second half (-0.18 ± 0.25 m·s, -3 ± 4%, p = 0.086). At 105 minutes, blood lactate concentrations reduced compared with that in the opening 30 minutes (-0.9 to -1.2 mmol·L, p ≤ 0.05). Blood pH (-0.03 to -0.04 units), base excess (-0.95 to -1.48 mmol·L), and bicarbonate concentrations (-0.9 ± 0.8 mmol·L) were depressed at 120 minutes compared with those at 105 minutes, baseline and half time (all p ≤ 0.05). There were no significant correlations between changes in acid-base balance and sprint speed (all p > 0.05). Although the perturbations in acid-base balance during ET were statistically significant, the decreases in blood pH, lactate, base excess, and bicarbonate concentrations may not represent metabolic acidosis or impairments in buffering capacity that are likely to explain reduced physical performance. Further research is warranted to investigate mechanisms of fatigue during ET and to develop interventions that attenuate decrements in performance.
Nasi, Milena; Cristani, Alessandro; Pinti, Marcello; Lamberti, Igor; Gibellini, Lara; De Biasi, Sara; Guazzaloca, Alessandro; Trenti, Tommaso; Cossarizza, Andrea
Exercise exerts various effects on the immune system, and evidence is emerging on its anti-inflammatory effects; the mechanisms on the basis of these modifications are poorly understood. Mitochondrial DNA (mtDNA) released from damaged cells acts as a molecule containing the so-called damage-associated molecular patterns and can trigger sterile inflammation. Indeed, high plasma levels of mtDNA are associated to several inflammatory conditions and physiological aging and longevity. The authors evaluated plasma mtDNA in professional male volleyball players during seasonal training and the possible correlation between mtDNA levels and clinical parameters, body composition, and physical performance. Plasma mtDNA was quantified by real-time PCR every 2 mo in 12 professional volleyball players (PVPs) during 2 consecutive seasons. As comparison, 20 healthy nonathlete male volunteers (NAs) were analyzed. The authors found lower levels of mtDNA in plasma of PVPs than in NAs. However, PVPs showed a decrease of circulating mtDNA only in the first season, while no appreciable variations were observed during the second season. No correlation was observed among mtDNA, hematochemical, and anthropometric parameters. Regular physical activity appeared associated with lower levels of circulating mtDNA, further confirming the protective, anti-inflammatory effect of exercise.
Balaban, Mehtap; Idilman, Ilkay S; Ipek, Ali; Ikiz, Sinem Sigit; Bektaser, Bulent; Gumus, Mehmet
Elastography is a new sonographic technique that evaluates the elasticity of different tissues such as the Achilles tendon. In this study, we aimed to investigate the elastographic findings of Achilles tendons in professional athletes in comparison with healthy volunteers. Twenty-one professional male volleyball players with no history of Achilles trauma were included in this study. Twenty-one healthy male volunteers with similar ages and body mass indices were selected as control participants. All participants underwent sonographic and elastographic evaluations of the Achilles tendons to evaluate Achilles tendon thickness and stiffness. We observed thickening in many of the thirds of the Achilles tendons (right proximal, right middle, left middle, and left distal thirds) of athletes in comparison with healthy volunteers. We did not detect any abnormalities according to the sonographic evaluations in both athletes and healthy volunteers. In the elastographic evaluations, we observed softening in the middle thirds of the Achilles tendons of athletes according to the main types (P < .001) and subtypes (P < .001 for right; and P = .002 for left middle third). There was no difference observed in the elastographic evaluations of the proximal and distal thirds. On sonography and elastography, we observed thickening and softening in Achilles tendons of athletes in comparison with healthy volunteers who had similar ages and body mass indices. These changes could be associated with early tendon degeneration. Further longitudinal studies may support this consideration. © 2016 by the American Institute of Ultrasound in Medicine.
Metcalfe, Alan J; Menaspà, Paolo; Villerius, Vincent; Quod, Marc; Peiffer, Jeremiah J; Govus, Andrew D; Abbiss, Chris R
To describe the within-season external workloads of professional male road cyclists for optimal training prescription. Training and racing of 4 international competitive professional male cyclists (age 24 ± 2 y, body mass 77.6 ± 1.5 kg) were monitored for 12 mo before the world team-time-trial championships. Three within-season phases leading up to the team-time-trial world championships on September 20, 2015, were defined as phase 1 (Oct-Jan), phase 2 (Feb-May), and phase 3 (June-Sept). Distance and time were compared between training and racing days and over each of the various phases. Times spent in absolute (500 W) and relative (0-1.9, 2.0-4.9, 5.0-7.9, >8 W/kg) power zones were also compared for the whole season and between phases 1-3. Total distance (3859 ± 959 vs 10911 ± 620 km) and time (240.5 ± 37.5 vs 337.5 ± 26 h) were lower (P distance decreased (P < .01) from phase 2 to phase 3 (10911 ± 620 vs 8411 ± 1399 km, respectively). Mean absolute (236 ± 12.1 vs 197 ± 3 W) and relative (3.1 ± 0 vs 2.5 ± 0 W/kg) power output were higher (P < .05) during racing than training, respectively. Volume and intensity differed between training and racing over each of 3 distinct within-season phases.
Mailhos, Alvaro; Buunk, Abraham P; Del Arca, Denise; Tutte, Verónica
Anatomical, cognitive and behavioral sex differences are widely recognized in many species. It has been proposed that some of these differences might result from the organizing effects of prenatal sex steroids. In humans, males usually exhibit higher levels of physical aggression and prowess. In this study, we analyze the relationship between second-to-fourth digit (2D:4D) ratios-a proxy for prenatal androgen levels-and foul play and sporting performance in a sample of junior soccer players from a professional Uruguayan soccer club. Our results show that the most aggressive players (i.e., those awarded one or more red cards) have a more masculine finger pattern (lower 2D:4D ratio), while no relationship could be found between sporting performance and 2D:4D ratios. The results are discussed in the context of previous findings. Aggr. Behav. 42:417-426, 2016. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.
Dane, Senol; Sekertekin, Mehmet Ali
Handedness and differences in interpersonal relations and aggressiveness were studied in 33 right-handed (M age=22.9 yr., SD=4.9) and 18 left-handed (M age=22.5 yr., SD=2.4) male soccer players who played actively in professional soccer leagues of Turkey. Hand preference on the Edinburgh Handedness Inventory and scores for destructiveness, assertiveness, and passive aggressiveness on a Turkish Aggressiveness Inventory, plus scores for sociability, benevolence, tenderheartedness, tolerance, and insistence on the Turkish Interpersonal Relations Inventory were examined. Mean destructive aggressiveness was higher for the left- than the right-handed athletes. Means on tolerance and insistence were higher for the right- than the left-handed athletes. Higher aggressiveness and less tolerance and insistence in the left-handers may be associated with their higher sports performance.
Ostojic, Sergej M
The purpose of this study was to examine the effects of acute creatine-monohydrate supplementation on soccer-specific performance in young soccer players. Twenty young male soccer players (16.6 +/- 1.9 years) participated in the study and were matched and allocated to 2 randomly assigned trials: ingesting creatine-monohydrate supplement (3 x 10-g doses) or placebo for 7 days. Before and after the supplementation protocol, each subject underwent a series of soccer-specific skill tests: dribble test, sprint-power test, endurance test, and vertical jump test. Specific dribble test times improved significantly in the creatine group (13.0 +/- 1.5 vs. 10.2 +/- 1.8 s; p test times were significantly improved after creatine-monohydrate supplementation (2.7 +/- 0.4 vs. 2.2 +/- 0.5 s; p test times, along with vertical jump height, were superior in creatine versus placebo trial (p test results within or between trials (p > .05). There were no between-trial differences in the placebo trial (p > .05). The main finding of the present study indicates that supplementation with creatine in young soccer players improved soccer-specific skill performance compared with ingestion of placebo.
Prognostic factors for specific lower extremity and spinal musculoskeletal injuries identified through medical screening and training load monitoring in professional football (soccer): a systematic review
Sergeant, Jamie C; Parkes, Matthew J; Callaghan, Michael J
Background Medical screening and load monitoring procedures are commonly used in professional football to assess factors perceived to be associated with injury. Objectives To identify prognostic factors (PFs) and models for lower extremity and spinal musculoskeletal injuries in professional/elite football players from medical screening and training load monitoring processes. Methods The MEDLINE, AMED, EMBASE, CINAHL Plus, SPORTDiscus and PubMed electronic bibliographic databases were searched (from inception to January 2017). Prospective and retrospective cohort studies of lower extremity and spinal musculoskeletal injury incidence in professional/elite football players aged between 16 and 40 years were included. The Quality in Prognostic Studies appraisal tool and the modified Grading of Recommendations Assessment, Development and Evaluation synthesis approach was used to assess the quality of the evidence. Results Fourteen studies were included. 16 specific lower extremity injury outcomes were identified. No spinal injury outcomes were identified. Meta-analysis was not possible due to heterogeneity and study quality. All evidence related to PFs and specific lower extremity injury outcomes was of very low to low quality. On the few occasions where multiple studies could be used to compare PFs and outcomes, only two factors demonstrated consensus. A history of previous hamstring injuries (HSI) and increasing age may be prognostic for future HSI in male players. Conclusions The assumed ability of medical screening tests to predict specific musculoskeletal injuries is not supported by the current evidence. Screening procedures should currently be considered as benchmarks of function or performance only. The prognostic value of load monitoring modalities is unknown. PMID:29177074
Koning, Ruud H.
In this paper, we estimate an ordered probit model for soccer results in The Netherlands. The result of a game is assumed to be determined by home advantage and quality differences of the opposing teams. The parameters of the model are used to assess whether competitive balance in Dutch professional
Paulo Reis Mourão
Full Text Available Amateur soccer teams are influenced by different local and regional factors from professional soccer teams. This article revisits the literature on the determinants of soccer performance and the sustainability of non-profit organizations. Using panel data techniques, we conclude that the outcomes of non-profit soccer teams depend on specific local markets and on the institutional environments of nonprofit organizations.
The mechanisms underlying the relative age effect in sport events have been investigated for more than two decades. The present study focused on the relationship between the relative age effect and lengths of professional careers among professional male Japanese baseball players. The birth dates of players and lengths of professional careers were collected from an official publication, and data were divided into four quarters (Q1: April-June; Q2: July-September; Q3: October-December; Q4: January-March of the following year) grouped by 3 years. Based on the data for Q4, the expected numbers for the lengths of professional careers were calculated for Q1, Q2, and Q3. The number of players with professional careers of more than 19 years was significantly smaller in Q4 than in Q1, Q2, and Q3. The relative age effect among professional male Japanese baseball players was associated with the lengths of professional careers. Relative age appears to be a very important factor for the development of expertise among male Japanese baseball players and involves long-term disadvantages after becoming professional players.
Full Text Available Background: Weight loss and decreasing the Body fat percentage (BF% is motivated to optimize performance. In order to achieve these, many supplements are used by athletes, however the possible negative or synergic effects have not been fully described in the literature, specifically in humans. The present study was conducted to investigate the co-administration effects of two common used supplements in body weight and BF% management to recommend athletes for safe weight and BF% reduction. Materials and Methods: In the present double-blind, randomized, parallel, placebo-controlled study, the effect of six-week co-administration of caffeine and carnitine was determined on changes in body weight (BW, BF%, serum leptin concentration and lipid profile (triglyceride, HDL Cholesterol, LDL Cholesterol and Total Cholesterol, fasting blood glucose (FBG, and free fatty acid (FFA changes. Twenty eight male teen soccer players from Ahvaz-Iran, were divided in three groups (group CafPlc, caffeine (6 mg/kg/day + dextrose; group CafCar, caffeine (6 mg/kg/day + carnitine (2g; and group Plc, dextrose. Results: Caffeine-carnitine had a lowering effect on BW (P=0.02 and BF% (P=0.03, compared to caffeine alone and placebo in male teen soccer players (mean age of 16.92 ± 0.76 years. TG was significantly decreased in CafCar (P=0.04. FFA levels were increased in CafCar (P=0.04 and there was significant differences between CafCar and Plc groups (P=0.01. FBG was increased in both CafPlc and CafCar (P=0.01 and P=0.02, respectively, with no significant differences between groups. Conclusion: The synergistic effect of caffeine-carnitine might be suggested to decrease the BF% and BW, besides it may prevent the increment of FFA levels; however it should be prescribed cautiously since it increased FBG levels.
Anderson, Liam; Orme, Patrick; Di Michele, Rocco; Close, Graeme L; Morgans, Ryland; Drust, Barry; Morton, James P
Muscle glycogen is the predominant energy source for soccer match play, though its importance for soccer training (where lower loads are observed) is not well known. In an attempt to better inform carbohydrate (CHO) guidelines, we quantified training load in English Premier League soccer players (n = 12) during a one-, two- and three-game week schedule (weekly training frequency was four, four and two, respectively). In a one-game week, training load was progressively reduced (P training load and periodisation was similar in the one- and two-game weeks, total accumulative distance (inclusive of both match and training load) was higher in a two-game week (32.5 ± 4.1 km) versus one-game week (25.9 ± 2 km). In contrast, daily training total distance was lower in the three-game week (2422 ± 251 m) versus the one- and two-game weeks, though accumulative weekly distance was highest in this week (35.5 ± 2.4 km) and more time (P 14.4 km · h(-1) (14%, 18% and 23% in the one-, two- and three-game weeks, respectively). Considering that high CHO availability improves physical match performance but high CHO availability attenuates molecular pathways regulating training adaptation (especially considering the low daily customary loads reported here, e.g., 3-5 km per day), we suggest daily CHO intake should be periodised according to weekly training and match schedules.
Hugo Paula Almeida da Rocha
Full Text Available Os objetivos do estudo foram: verificar como os atletas das categorias de base do futebol conciliam sua rotina de treinamento com a escolarização básica e; como os estudantes-atletas percebem o significado da escola na busca por uma ocupação futura. Para esta análise, foram realizadas 12 entrevistas semiestruturadas com jogadores das categorias de base - na faixa de idade entre 15 e 20 anos - de quatro clubes de futebol do Estado do Rio de Janeiro. Observamos que os atletas adotam diferentes estratégias de conciliação entre as rotinas no futebol e na escola, mediados pelos mecanismos de flexibilização adotados pelos estabelecimentos de ensino e/ou professores, com a anuência dos pais. Concluímos que essas estratégias de conciliação têm como finalidade a permanência do atleta na escola. Embora tenhamos refletido sobre os mecanismos de flexibilização adotados por professores e diretores, não podemos medir o impacto causado no aprendizado e na trajetória escolar desses jovens atletas de futebol.The goals of the study were: to verify how young soccer players manage to conciliate their training routines with school; and how the student-athletes perceive the importance of school in the search for a future occupation. For this analysis, we made 12 interviews half-structuralized with young players - from 15 to 20 years - of four soccer teams from Rio de Janeiro. We observed that these athletes find distinct strategies of conciliation between soccer and school routines, mediated by mechanisms of loosening adopted by the educational establishments/teachers, with the consent of the parents. We concluded that the purpose of this agreement is the permanence of the athlete in the school. Although we have reflected on the mechanisms of loosening adopted by teachers and principals, we cannot infer the impact caused by such mechanisms in the institutionalized education of these young athletes of soccer.
Tiago Bortolini; Patrícia Bado; Sebastian Hoefle; Annerose Engel; Roland Zahn; Ricardo de Oliveira Souza; Jean-Claude Dreher; Jorge Moll
.... Here, we used soccer fandom as an ecological framing of group membership to investigate the neural mechanisms underlying ingroup altruistic behaviour in male fans using event-related functional magnetic resonance...
Bredtmann, Julia; Crede, Carsten J.; Otten, Sebastian
In this paper, we propose a new estimation strategy that uses the variation in success between the male and the female national soccer team within a country to identify the causal impact of gender equality on women’s soccer performance. In particular, we analyze whether within-country variations...... in labor force participation rates and life expectancies between the genders, which serve as measures for the country’s gender equality, are able to explain diff erences in the international success of male and female national soccer teams. Our results reveal that diff erences in male and female labor...... force participation rates and life expectancies are able to explain the international soccer performance of female teams, but not that of male teams, suggesting that gender equality is an important driver of female sport success....
Full Text Available This study aimed at analyzing the visual and auditory simple reaction times in soccer players from differing categories and field positions. Participated in the study 49 male soccer players, amateurs and professionals, occupying the field positions of goalkeeper, center defender, right and left defender, halfback, midfielder, and forward. Data collection was carried out through a system composed by a switch, a mechanism of visual and auditory stimuli and appropriate acquisition software. Data were analyzed through descriptive and inferential statistics (p < .05. When comparing categories, there was no difference in visual reaction time (VRT. Professionals showed faster auditory reaction times (ART than amateurs did. Regarding field positions, goalkeepers showed significantly faster VRT than midfielders and there was no difference in terms of ART. Main differences between players from differing categories and field positions may be due to the adoption of more complex strategies in retaining and using visual information in specific situations. ART may be less important in soccer, since this is essentially a visual game.
Goff, John Eric [Department of Physics, Lynchburg College, Lynchburg, VA 24501 (United States); Carre, Matt J, E-mail: email@example.com [Department of Mechanical Engineering, University of Sheffield, Sheffield S1 3JD (United Kingdom)
We performed experiments in which a soccer ball was launched from a machine while two high-speed cameras recorded portions of the trajectory. Using the trajectory data and published drag coefficients, we extracted lift coefficients for a soccer ball. We determined lift coefficients for a wide range of spin parameters, including several spin parameters that have not been obtained by today's wind tunnels. Our trajectory analysis technique is not only a valuable tool for professional sports scientists, it is also accessible to students with a background in undergraduate-level classical mechanics.
Dos Santos Glória, Igor Phillip; Politti, Fabiano; Junior, Ernesto Cesar Pinto Leal; Lucareli, Paulo Roberto Garcia; Herpich, Carolina Marciela; Antonialli, Fernanda Colella; de Paula Gomes, Cid André Fidelis; de Oliveira Gonzalez, Tabajara; Biasotto-Gonzalez, Daniela Aparecida
Kinesio taping consists of the attachment of a thin elastic tape over specific muscles, the thickness of which is similar to that of the epidermis. The aim of the present study was to compare the effect of Kinesio taping and placebo taping on muscle torque, muscle activity and jumping performance soccer players. Thirty athletes were randomly allocated to two groups (Group A: Kinesio taping and Group B: placebo taping). The participants were instructed to perform the Hop test's and were submitted to an isokinetic evaluation of the knee extensors as well as an electromyographic evaluation of the retus femoris muscle of the dominant lower limb. Next, Kinesio taping was performed for the activation of the rectus femoris muscle in Group A and placebo taping was performed in Group B. The participants were reevaluated 30 minutes after taping and 24 hours after the first evaluation using the same tests. Intra-group and inter-group comparisons were made considering the three evaluation times. No statistically significant differences were found between groups at any evaluation time regarding the Hop test's, root mean square of the electromyographic signal or peak torque of the knee extensors of the dominant lower limb (p>0.05). Kinesio taping for the activation of the rectus femoris muscle has no effect on peak muscle torque, muscle activity or jumping performance among soccer players.
Randers, Morten Bredsgaard; Andersen, Jesper Løvind; Petersen, Jesper
Abstract The aim was to investigate performance variables and indicators of cardiovascular health profile in elderly soccer players (SP, n = 11) compared to endurance-trained (ET, n = 8), strength-trained (ST, n = 7) and untrained (UT, n = 7) age-matched men. The 33 men aged 65-85 years underwent...... a testing protocol including measurements of cycle performance, maximal oxygen uptake (VO2max) and body composition, and muscle fibre types and capillarisation were determined from m. vastus lateralis biopsy. In SP, time to exhaustion was longer (16.3 ± 2.0 min; P ...
Full Text Available Purpose. The present study aimed to examine the current methods employed to assess anticipation in soccer players as well as to elicit the main findings of recent studies. Methods. The study was carried out in systematic review form and its sample comprised nine scientific papers published in academic journals. Only the studies involving soccer players (professionals and amateurs, except goalkeepers were included in this review. Results and conclusions. We observed that most of the studies employed video footage obtained from soccer matches, which are occluded at a given point for study participants to quickly and precisely elicit the positions of opponents, teammates and the ball as well as anticipate actions (dribbling, shooting, passing from surrounding players (teammates and opponents. In addition, the studies compared the performance of players from both high and low competitive levels in anticipation tasks.
Setuain, Igor; Lecumberri, Pablo; Izquierdo, Mikel
The present research aimed to describe an inertial unit (IU)-based sprint mechanics evaluation model for assessing players' readiness to return to competition after suffering a grade I hamstring injury. A professional male football player (age 19years; height 177cm; weight 70kg, midfielder, Spanish, 3° Division) with a grade 1 biceps femoris injury was evaluated at pre-season, at return to play after injury and at the end of the competitive season. Sprint mechanics were analyzed via the use of an inertial orientation tracker (Xsens Technologies B.V. Enschede, Netherlands) attached over the L3-L4 region of the subject's lumbar spine. Sprint mechanics such as horizontal components of ground reaction force were assessed in both legs during sprinting actions. Findings and interpretation: Both the coefficient of the horizontal force application (SFV) and the ratio of forces (DRF) applied at increasing velocity were decreased in the injured limb compared with the contralateral healthy limb at the return to play evaluation (73% and 76% reductions, respectively) and returned to symmetrical levels at the end-season evaluation. Copyright © 2017 Elsevier Ltd. All rights reserved.
Vänttinen, T; Blomqvist, M; Luhtanen, P; Häkkinen, K
This study of perceptual and motor skills in soccer players was conducted on adolescent males. The goals were to monitor the development of general perceptual motor skills in nonsoccer-playing and soccer-playing groups (n = 245), to examine the relationship between physical maturity and general perceptual motor skills (n = 41), and to compare the differences in general perceptual motor skills between groups with different soccer expertise (n = 142). The measured variables were simple reaction time, peripheral awareness, eye-hand-foot coordination, and testosterone blood level. The results suggested that general perceptual motor skills improved with age, the development of these skills was related to participants' blood testosterone concentration (especially between 12 and 14 years), and general perceptual motor skills improved with soccer expertise. However, the differences between subelite and elite soccer players were not meaningful enough to encourage practitioners to test general perceptual motor skills on a large scale when evaluating the potential of young players.
Higgins, John P; Andino, Aldo
Sudden cardiac death (SCD) in young competitive athletes (athletes at a 2.5 times higher risk. Soccer is the most popular sport in the world, played by people of all ages. However, unfortunately it is cardiovascular diseases such as hypertrophic cardiomyopathy and arrhythmogenic right ventricular cardiomyopathy that have subtly missed screening and claimed the lives of soccer stars such as Marc Vivien Foe and Antonio Puerta during live action on the field and on an internationally televised stage. This paper covers the physiological demands of soccer and the relationship between soccer and SCD. It also reviews the most common causes of SCD in young athletes, discusses the current guidelines in place by The Fédération Internationale de Football Association (FIFA) for screening among professional soccer players, and the precautions that have been put in place to prevent SCD on the field in professional soccer.
Fidelix, Yara Lucy; Berria, Juliane; Ferrari, Elisa Pinheiro; Ortiz, Jaelson Gonçalves; Cetolin, Tiago; Petroski, Edio Luiz
The aim of this study was to identify the morphological configuration of youth athletes from professional soccer clubs and to verify their differences according to the tactical position on the field. Overall, 67 male players aged 15 to 17 years were evaluated. The examined anthropometric measurements included body mass, body height, skinfolds (triceps, subscapular, supraspinal and medial calf), girths (flexed and tensed arm and calf) and breadths (humerus and femur). For statistical purposes, analysis of variance and post hoc Bonferroni and Kruskal-Wallis tests were used. We concluded that goalkeepers were heavier and taller than center backs (p = 0.015 and p = 0.001), midfielders (p = 0.005 and p somatotype for defense, forward and goalkeeper positions was a balanced mesomorph. Midfield players showed ectomorphic-mesomorph characteristics. It was concluded that goalkeepers were characterized as being taller and heavier and that somatotype features of athletes were similar between positions, except for midfield players. PMID:25414758
The aim of the current study was to indicate the biochemical changes during the preparation and competitive soccer period. The literature review showed that biochemical parameters such as transaminases, enzymes and other factors change significantly from the preparation to the competitive period. The sample of the study included twenty five professional soccer players whose biochemical parameters assessed in the beginning of the preparation period, in the middle, in the end of the preparation...
Tessitore, Antonio; Perroni, Fabrizio; Cortis, Cristina; Meeusen, Romain; Lupo, Corrado; Capranica, Laura
This study aimed to verify whether coordination improves as a result of a preseason soccer training. During 5 experimental sessions (days 1, 6, 11, 15, and 19), 16 semiprofessional male soccer players (22.0 ± 3.6 years) were administered 3 specific soccer tests (speed dribbling, shooting a dead ball, and shooting from a pass) and an interlimb coordination test (total duration of a trial: 60 seconds), consisting of isodirectional and nonisodirectional synchronized (1:1 ratio) hand and foot flexions and extensions at an increasing velocity of execution (80, 120, and 180 b·min(-1)). Furthermore, subjective ratings were monitored to assess the recovery state (RestQ) of the players, their perceived exertion (rating of perceived exertion [RPE]) for the whole body, and the perceived muscle pain (rating of muscle pain [RMP]) for the lower limbs and the internal training load by means of the session-RPE method. The ratios between post and pretraining RPE and RMP increased only during the first 2 experimental sessions and decreased after the second week of the training camp (p = 0.001). The Rest-Q showed increases (p fatigue, physical complaints dimensions. Throughout the preseason, the players improved their speed dribbling (p = 0.03), Shooting from a Pass (p = 0.02), and interlimb coordination (p coordination tests succeeded in discriminating coordination in soccer players and could integrate field test batteries during the whole soccer season, because they were easily and inexpensively administrable by coaches.
Full Text Available The purpose of this study was to determine the reliability and usefulness of the 30-15 Intermittent Fitness Test (30-15IFT in professional male and female futsal players. Thirteen male (24.4 ± 5.6 years; 174.5 ± 10.3 cm; 70.3 ± 9.9 kg and fourteen female (23.3 ± 4.5 years; 165.8 ± 6.2 cm; 61.7 ± 5.5 kg professional futsal players performed the 30-15IFT on two occasions, separated by 5 days. Maximal intermittent running velocity (VIFT and heart rate at exhaustion (HRpeak data were collected for both tests. Reliability was assessed by the intraclass correlation coefficient (ICC, typical error (TE expressed as a coefficient of variation (CV, and smallest worthwhile change (SWC. VIFT demonstrated very good reliability between sessions, both for male (ICC = 0.92 and female (ICC = 0.96 players. As the TE for VIFT and HRpeak was similar to the calculated SWC for both male and female players, the usefulness of the test was rated as “medium”. A change in performance of at least 2 stages in male players, or a change of more than 1 stage in female players could be interpreted as a meaningful change in aerobic futsal fitness. The results of this study demonstrate that the 30-15IFT is both a reliable and useful test for male and female professional futsal players.
Agricola, Rintje; Heijboer, Marinus P; Ginai, Abida Z; Roels, Pauline; Zadpoor, Amir A; Verhaar, Jan A N; Weinans, Harrie; Waarsing, Jan H
A cam deformity is a major risk factor for hip osteoarthritis, and its formation is thought to be influenced by high-impact sporting activities during growth. To (1) prospectively study whether a cam deformity can evolve over time in adolescents and whether its formation only occurs during skeletal maturation and (2) examine whether clinical or radiographic features can predict the formation of a cam deformity. Cohort study (prognosis); Level of evidence, 2. Preprofessional soccer players (N = 63; mean age, 14.43 years; range, 12-19 years) participated both at baseline and follow-up (mean follow-up, 2.4 ± 0.06 years). At both time points, standardized anteroposterior and frog-leg lateral radiographs were obtained. For each hip, the α angle was measured, and the anterosuperior head-neck junction was classified by a 3-point visual system as normal, flattened, or having a prominence. Differences between baseline and follow-up values for the α angle and the prevalence of each visual hip classification were calculated. Additionally, the amount of internal hip rotation, growth plate extension into the neck, and neck shaft angle were determined. Overall, there was a significant increase in the prevalence of a cam deformity during follow-up. In boys aged 12 and 13 years at baseline, the prevalence of a flattened head-neck junction increased significantly during follow-up (13.6% to 50.0%; P = .002). In all hips with an open growth plate at baseline, the prevalence of a prominence increased from 2.1% to 17.7% (P = .002). After closure of the proximal femoral growth plate, there was no significant increase in the prevalence or increase in severity of a cam deformity. The α angle increased significantly from 59.4° at baseline to 61.3° at follow-up (P = .018). The amount of growth plate extension was significantly associated with the α angle and hip classification (P = .001). A small neck shaft angle and limited internal rotation were associated with cam deformities and
Consumo máximo de oxigênio e limiar anaeróbio de jogadores de futebol: comparação entre as diferentes posições Maximal oxygen uptake and anaerobic threshold in professional soccer players: comparison between different positions
Full Text Available O grau de desenvolvimento das capacidades físicas no futebol é fator determinante do nível desportivo do jogador. O objetivo do presente estudo foi comparar valores de limiar anaeróbio e consumo máximo de oxigênio entre jogadores profissionais de futebol de diferentes posições. Para tanto, 25 atletas (idade = 22,08 ± 8,28 anos, peso = 76,12 ± 9,8kg, altura = 179,8 ± 7,1cm e relação corporal = 12,21 ± 3,67% de gordura corporal foram divididos em cinco grupos, como se segue: goleiros (GO, zagueiros (ZA, laterais (LA, meio-campistas (MC e atacantes (AT. O VO2max foi determinado em esteira ergométrica através de análise direta e a velocidade de corrida correspondente ao limiar anaeróbio fixo de 4mM (V4mM, em teste de campo (2 x 1.000m a 90 e 95% da velocidade máxima para a distância através de interpolação linear. A V4mM foi menor (p The development of physical capacities in soccer determines the player's level of performance. The aim of this study was to compare anaerobic threshold and maximal oxygen uptake values between professional soccer players playing in different positions. Twenty-five male athletes (age = 22.08 ± 8.82 years, weight = 76.12 ± 9.8 kg, height = 179.8 ± 7.1 cm and body composition = 12.21 ± 3.67% body fat were divided into five groups as follows: goalkeepers (GO, full backs (FB, sideways (SW, midfield (MF and forwards (FO and evaluated twice in two to three days period. For direct maximal oxygen uptake (VO2max determination, subjects were submitted to an incremental continuous treadmill exercise until fatigue occurred. Two-speeds track test (2 x 1,000 m at 90 and 95% of maximal speed and linear interpolation were employed for 4mM blood lactate running speed (V4mM or anaerobic threshold assessment. Main results are present below. V4mM for GO group was significantly lower (p 0.05 from one another. Since these athletes were under the same training program, the differences above may be explained by
Schenk, Kai; Bizzini, Mario; Gatterer, Hannes
Referees are an integral part of soccer and their performance is fundamental for regular match flow, irrespective of the competition level or age classes. So far, scientific interest was mainly limited to aspects of exercise physiology and match performance of soccer referees, whereas recommendations for nutrition were adopted from active professional soccer. In contrast to elite soccer players most referees are non-professional and engaged in different occupations. Furthermore, elite referees and soccer players differ in regard to age, body composition, aerobic capacity and training load. Thus, referees' caloric needs and recommended daily carbohydrate intake may generally be lower compared to active soccer players, with higher intakes limited to periods of increased training load and match days or for referees engaged in physical demanding occupations. With respect to fluid intake, pre-match and in-match hydration strategies generally valid in sports are recommended also for referees to avoid cognitive and physical performance loss, especially when officiating in extreme climates and altitude. In contrast to elite soccer, professional assistance concerning nutrition and training is rarely available for national elite referees of most countries. Therefore, special attention on education about adequate nutrition and fluid intake, about the dietary prevention of deficiencies (iron in female referees, vitamin D irrespective of sex and age) and basic precautions for travels abroad is warranted. In conclusion, the simple adoption of nutritional considerations from active soccer for referees may not be appropriate. Recommendations should respect gender differences, population specific physical characteristics and demands just as well as individual characteristics and special needs. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Iaia, F Marcello; Fiorenza, Matteo; Perri, Enrico; Alberti, Giampietro; Millet, Grégoire P; Bangsbo, Jens
In order to better understand the specificity of training adaptations, we compared the effects of two different anaerobic training regimes on various types of soccer-related exercise performances. During the last 3 weeks of the competitive season, thirteen young male professional soccer players (age 18.5±1 yr, height 179.5±6.5 cm, body mass 74.3±6.5 kg) reduced the training volume by ~20% and replaced their habitual fitness conditioning work with either speed endurance production (SEP; n = 6) or speed endurance maintenance (SEM; n = 7) training, three times per wk. SEP training consisted of 6-8 reps of 20-s all-out running bouts followed by 2 min of passive recovery, whereas SEM training was characterized by 6-8 x 20-s all-out efforts interspersed with 40 s of passive recovery. SEP training reduced (prepeated sprint ability test (RSAt) by 2.5%. SEM training improved the 200-m sprint performance (from 26.59±0.70 to 26.02±0.62 s, psoccer-related physical performance. SEP improved repeated sprint and high-intensity intermittent exercise performance, whereas SEM increased muscles' ability to maximize fatigue tolerance and maintain speed development during both repeated all-out and continuous short-duration maximal exercises. These results provide new insight into the precise nature of a stimulus necessary to improve specific types of athletic performance in trained young soccer players.
Rijken, Noortje H; Soer, Remko; de Maar, Ewold; Prins, Hilco; Teeuw, Wouter B; Peuscher, Jan; Oosterveld, Frits G J
The aim of this pilot study was to investigate the effects of an intervention consisting of mental coaching combined with either electro encephalogram (EEG) alpha power feedback or heart rate variability (HRV) feedback on HRV, EEG outcomes and self-reported factors related to stress, performance, recovery and sleep quality in elite athletes. A prospective pilot study was performed with two distinct cohorts. Soccer players were provided with four sessions of mental coaching combined with daily HRV biofeedback (Group A); track and field athletes were provided with four sessions of mental coaching in combination with daily neurofeedback (Group B). Measurements were performed at baseline, post intervention and at 5 weeks follow-up. Objective measures: EEG and ECG. Subjective measures: Numeric Rating Scale for performance, Pittsburgh Sleep Quality Index, Rest and Stress Questionnaire and Sports Improvement-60. Group characteristics were too distinct to compare the interventions. Linear mixed models were used to analyze differences within groups over time. In Group A, significant changes over time were present in alpha power at 5 of 7 EEG locations (p performance-related outcomes and stress reduction. Further research is needed to elucidate the effects of either type of feedback and to compare effects with a control group.
Otağ, Aynur; Hazar, Muhsin; Otağ, İlhan; Beyleroğlu, Malik
[Purpose] The performance of female athletes during their menstrual period has attracted the attention of researchers for many years. It is known that the menstrual period changes with exercise. Alpha-fetoprotein (AFP) is an oncofetal protein. In this study, the effect of maximal aerobic exercise in the luteal phase on some hormones and AFP in female athletes was researched. [Subjects and Methods] Twelve volunteers and healthy female footballers with normal menstrual cycles volunteered for this study as subjects. All the participants performed a shuttle run test. Blood samples were taken before, after, and one hour after exercise. Serum AFP, estrogen, progesterone, follicle-stimulating hormone (FSH), and luteinizing hormone (LH) values were measured using an auto analyzer and original kits. Heart rate measurements were performed before and after the exercise. [Results] AFP activity had significantly decreased after 1 h of recovery from the exercise in the female soccer players, and estrogen and LH activity had significantly increased immediately after the exercise. Progesterone activity had significantly decreased immediately after the exercise. FSH values had significantly increased immediately after the exercise. [Conclusion] The results of the present study show there were significant decreases in the values of AFP, which is a cancer parameter, 1 hour after the exercise. This result may be valuable in future physiotherapy studies on the relationship between exercise and cancer. PMID:27134362
Bredtmann, Julia; Carsten J. Crede; Otten, Sebastian
In this paper, we propose a new estimation strategy that uses the variation in success between the male and the female national soccer team within a country to identify the causal impact of gender equality on women’s soccer performance. In particular, we analyze whether within-country variations in labor force participation rates and life expectancies between the genders, which serve as measures for the country’s gender equality, are able to explain diff erences in the international success o...
Baran, Funda; Aktop, Abdurrahman; Ozer, Dilara; Nalbant, Sibel; Aglamis, Ece; Barak, Sharon; Hutzler, Yeshayahu
The study investigated the effects of a Special Olympics (SO) Unified Sport (UNS) soccer program on anthropometry, physical fitness and soccer skills of male youth athletes with and without intellectual disabilities (ID) who participated in a training group (TRG) and in a comparison group (CG) without specific training. Youth with ID (WID) were…
Hou, D.; Driessen, Theo
Inspired by the first lustrum of the Club Positioning Matrix (CPM) for professional Dutch soccer teams, we model the interaction between soccer teams and their potential fans as a cooperative cost game based on the annual voluntary sponsorships of fans in order to validate their fan registration in
Lee, Seungbum; Han, Keunsu
Whereas there have been many academic studies on European soccer team supporters, relatively few studies have looked at supporters in Asia, especially regarding their supporting behavior and culture. Broadly, the purpose of this paper is to describe the behavior and culture of supporters of the Korean professional soccer league (K-League).…
Gusti Made Trisetya Putra
Full Text Available In the modern soccer era, soccer is already considered as an entertainment, even modern soccer already become as an industry or a business that considered can bring a great profit to the club owner. One of the most important factor in building a team is young age soccer player development. Right young age soccer player development method, can be very helpful in establish a good team. A professional team must have acoach, for the first team or junior team. The duties of a coach is determine a right position for soccer player in the game, this duties sometimes make a coach is hard to making a right decision. This research will discussabout how to design a decision support system for determine soccer player using naive bayes technique. Data mining used naive bayes technique for find a prediction for soccer player based on the player skill test result. From this research result, it can be seen that by using decision support system using data mining with naive bayes technique can be help coach performance in determine position for soccer player especially for young age soccer player development so that can help coach in the making right decision effectively and efficiently.
Myrick, Karen M
Soccer is currently the most popular and fastest growing sport worldwide, with approximately 265 million registered soccer players existing around the world. The popularity of the sport, coupled with the high incidence of 18.8-21.5 head injuries per 1,000 player hours reported, make it essential that clinicians, coaches, and the athletes, have a solid understanding of head injuries. The successful rehabilitation of athletes with head injuries relies upon early and accurate identification strategies and implementation of appropriate return to play measures across all areas in the continuum of care. Soccer is a frequently played sport, and head injuries are common. Therefore, it is imperative that clinicians, coaches, and the athletes themselves have a solid understanding of head injury prevention, diagnosis, and treatment options. The purpose of this article was to provide rehabilitation nurses with current information regarding frequently occurring head injuries in the widespread sport of soccer. © 2015 Association of Rehabilitation Nurses.
Paterson, Anne [Royal Belfast Hospital for Sick Children, Radiology Department, Belfast (United Kingdom)
Soccer is the most popular sport in the world, with FIFA recognising more than 265 million amateur players. Despite the fact that soccer is a contact sport, it is perceived to be relatively safe to play, a factor that has contributed to its status as the fastest growing team sport in the USA. Acute and minor injuries predominate in the statistics, with contusions and abrasions being the most commonly recorded. As would be expected, the majority of soccer injuries are to the lower limbs, with serious truncal and spinal trauma being rare. This article examines the type and anatomic location of injuries sustained by children and adolescents who play soccer, and the main mechanisms whereby such injuries occur. The risk factors underpinning injury occurrence are considered, along with injury avoidance tactics. (orig.)
Souglis, Athanasios G; Chryssanthopoulos, Costas I; Travlos, Antonios K; Zorzou, Amalia E; Gissis, Ioannis T; Papadopoulos, Christos N; Sotiropoulos, Aristomenis A
The purpose of this study was to compare the distances covered during a 11-a-side soccer match after players had consumed either a high carbohydrate (CHO) or a low CHO diet. Twenty-two male professional soccer players formed 2 teams (A and B), of similar age, body characteristics, and training experience. The 2 teams played against each other twice with a week interval between. For 3.5 days before the first match, the players of team A followed a high CHO diet that provided 8 g CHO per kg body mass (BM) (HC), whereas team B players followed a low CHO diet that provided 3 g CHO per kg BM (LC) for the same time period. Before the second match the dietary treatment was reversed and followed for the same time period. Training during the study was controlled, and distances covered were measured using global positioning system technology. Every player covered a greater total distance in HC compared with the distance covered in LC (HC: 9,380 ± 98 m vs. LC: 8,077 ± 109 m; p players followed the HC treatment, they won the match (team A vs. team B: 3-1 for the first game and 1-2 for the second game). The HC diet probably helped players to cover a greater distance compared with LC. Soccer players should avoid eating a low (3 g CHO per kg BM) CHO diet 3-4 days before an important soccer match and have a high CHO intake that provides at least 8 g CHO per kg BM.
A retrospective study on anthropometrical, physical fitness, and motor coordination characteristics that influence dropout, contract status, and first-team playing time in high-level soccer players aged eight to eighteen years.
Deprez, Dieter N; Fransen, Job; Lenoir, Matthieu; Philippaerts, Renaat M; Vaeyens, Roel
The goal of this article was twofold, and a 2-study approach was conducted. The first study aimed to expose the anthropometrical, physical performance, and motor coordination characteristics that influence dropout from a high-level soccer training program in players aged 8-16 years. The mixed-longitudinal sample included 388 Belgian youth soccer players who were assigned to either a "club group" or a "dropout group." In the second study, cross-sectional data of anthropometry, physical performance, and motor coordination were retrospectively explored to investigate which characteristics influence future contract status (contract vs. no contract group) and first-team playing time for 72 high-level youth soccer players (mean age = 16.2 years). Generally, club players outperformed their dropout peers for motor coordination, soccer-specific aerobic endurance, and speed. Anthropometry and estimated maturity status did not discriminate between club and dropout players. Contract players jumped further (p = 0.011) and had faster times for a 5-m sprint (p = 0.041) than no contract players. The following prediction equation explains 16.7% of the variance in future playing minutes in adolescent youth male soccer players: -2,869.3 + 14.6 × standing broad jump. Practitioners should include the evaluation of motor coordination, aerobic endurance, and speed performances to distinguish high-level soccer players further succeeding a talent development program and future dropout players, between 8 and 16 years. From the age of 16 years, measures of explosivity are supportive when selecting players into a future professional soccer career.
Estudo comparativo do consumo de oxigênio e limiar anaeróbio em um teste de esforço progressivo entre atletas profissionais de futebol e futsal Estudio comparativo del consumo de oxígeno y límite anaeróbico en un test de esfuerzo progresivo entre atletas profesionales de fútbol y fútbol de salón Comparative study of the oxygen consumption and anaerobic threshold in a progressive exertion test in professional soccer and indoor soccer athletes
Ernesto Cesar Pinto Leal Junior
progresivo. Participaron voluntariamente 31 individuos del sexo masculino, entre ellos: 19 atletas profesionales de fútbol, y 12 atletas profesionales de fútbol de salón. Los deportistas fueron sometidos a un protocolo de evaluación cardiorrespiratoria progresiva por el método ergoespirométrico, y os resultados fueron analizados en relación a su diferencia estadística a través del test t-Student (p 0,05; a pesar de eso hubo diferencia estadística entre los dos grupos en relación al límite anaeróbico (LA (p Oxygen consumption (VO2 has been very useful for the functional evaluation of athletes. Ergospirometry is a non-invasive procedure used to evaluate the physical performance or the functional ability of an individual, connecting the analysis of the inspired gases with the respiratory variables. This evaluation method is extremely important to sports, since it brings significant contribution in the verification of indices of cardiorespiratory aptitude, which is the case f the maximal oxygen consumption (VO2 max and the anaerobic threshold (AT. The present study had as objective to compare oxygen consumption and anaerobic threshold in professional soccer and indoor soccer athletes in a progressive test. 31 male individuals voluntarily participated in the test, being: 19 professional soccer athletes and 12 professional indoor soccer athletes. The athletes were submitted to a progressive cardiorespiratory evaluation protocol through the ergospirometric method, and the results were analyzed concerning their statistical difference through the t-Student test (p 0,05; however, there was statistically difference between the two groups concerning the anaerobic threshold (AT (p < 0,05. Based on the results obtained in our study we concluded that even practicing sports with different characteristics, the athletes from both groups have similar indices of oxygen consumption. Nevertheless, the anaerobic threshold between the two groups did not present the same similarity
Tierney, Ryan T; Higgins, Michael; Caswell, Shane V; Brady, Jessica; McHardy, Krista; Driban, Jeffrey B; Darvish, Kurosh
Researchers have indicated that female soccer players may be at greater risk of concussion compared with their male counterparts. Soccer headgear is marketed for reducing head acceleration and risk of concussion. To determine the effect of sex and soccer headgear on head impact kinematics and dynamic stabilization during soccer heading. Cross-sectional design. Research laboratory. Forty-four college-aged soccer players (29 women, 15 men). Using a head impact model, participants performed 4 soccer headers under 3 headgear conditions (control, Head Blast Soccer Band, and Full90 Select Performance Headguard). Dependent variables assessed before soccer heading were head-neck anthropometrics and isometric neck muscle strength, and those assessed during soccer headers were resultant linear head acceleration, Head Injury Criteria (HIC(36)), and superficial neck muscle electromyography. Statistical analyses included multivariate and univariate analyses of variance with repeated measures, independent-samples t tests, appropriate follow-up analyses of variance and post hoc t tests, and Pearson product moment correlations (alpha = .05). Head acceleration in women was 32% and 44% greater than in men when wearing the Head Blast (21.5 g versus 16.3 g) and Full90 Select (21.8 g versus 15.2 g), respectively (P headgear. Our results are important clinically because they indicate that soccer headgear may not be an appropriate head injury prevention tool for all athletes.
M.Cur. (Professional Nursing Science: Nursing Management) The history of nursing focuses almost exclusively on a female-dominated profession, created with the assumption that such a role is inherently natural to women only. Yet, men have worked as nurses since the profession’s infancy, 250 BC, but their contributions seem to be unnoticed and underrepresented. Male nurses ascribe to a minority status within the nursing profession, with only 6.8% currently registered with the South African N...
Bakken, A; Targett, S; Bere, T; Eirale, C; Farooq, A; Tol, J L; Whiteley, R; Witvrouw, E; Khan, K M; Bahr, R
The Nine Plus screening battery test (9+) is a functional movement test intended to identify limitations in fundamental movement patterns predisposing athletes to injury. However, the interseason variability is unknown. To examine the variability of the 9+ test between 2 consecutive seasons in professional male football players. Asymptomatic Qatar Star League players (n=220) completed the 9+ at the beginning of the 2013 and 2014 seasons. Time-loss injuries in training and matches were obtained from the Aspetar Injury and Illness Surveillance Program. No intervention was initiated between test occasions. A significant increase in the mean total score of 1.6 points (95% CI 1.0 to 2.2, p<0.001) was found from season 1 (22.2±4.1 (SD)) to season 2 (23.8±3.3). The variability was large, as shown by an intraclass correlation coefficient (ICC) of 0.24 (95% CI 0.11 to 0.36) and a minimal detectable change (MDC) of 8.7 points. Of the 220 players, 136 (61.8%) suffered a time-loss injury between the 2 tests. There was an improvement in mean total scores in the injured (+2.0±0.4 (SE), p<0.001) group but not in the uninjured group (+0.9±0.5, p=0.089). The variability from season 1 to season 2 was large both in the injured (ICC 0.25, 0.09 to 0.40, MDC 8.3) and uninjured (ICC 0.24, 0.02 to 0.43, MDC 9.1) groups. The 9+ demonstrated substantial intraindividual variability in the total score between 2 consecutive seasons, irrespective of injury. A change above 8 points is necessary to represent a real change in the 9+ test between seasons. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
Full Text Available Problem Statement: Soccer is a game in which fatigue could influence player's performance. The aim of thepresent study was to evaluate the effect of fatigue, induced acutely, by a specifically soccer activities circuit onkicking velocity.Approach: Nine experienced male soccer players performed prior and after the implementation of an intensiveand intermittent exercise protocol maximal instep kicks.Results: Analysis of variance designs with repeated measures indicated a significant difference (p<0.05 in thekicking velocity before and after performing the circuit.Conclusions/Recommendations: The present’s results confirmed the initial hypothesis of the negative influenceof fatigue on velocity of the kicking soccer
Branci, Sonia; Thorborg, Kristian; Bech, Birthe Højlund; Boesen, Mikael; Nielsen, Michael Bachmann; Hölmich, Per
Soccer players are commonly affected by long-standing adductor-related groin pain (ARGP), but the clinical significance of MRI findings in these athletes is largely unknown. Our aims were (1) to evaluate whether MRI findings are associated with long-standing ARGP in soccer players, (2) to assess MRI findings in asymptomatic soccer players and non-soccer playing controls. This cross-sectional study included 28 male soccer players with long-standing ARGP, 17 male asymptomatic soccer players and 20 male asymptomatic non-soccer playing athletes of matching age and athletic exposure. Participants underwent identical standardised and reliable clinical examination, and MRI scans (3 T) of the pelvis performed by a blinded observer. Images were consensus rated by three blinded radiologists according to a standardised MRI evaluation protocol. The associations between clinical adductor-related findings and pathological MRI findings were investigated with χ(2) statistics and OR. Central disc protrusion (p=0.027) and higher grades of pubic bone marrow oedema (BMO; p=0.027) were significantly more present in symptomatic players than asymptomatic players. However, up to 71% of asymptomatic soccer players displayed different positive MRI findings, and asymptomatic soccer players had significantly higher odds (OR ranging from 6.3 to 13.3) for BMO, adductor tendinopathy and degenerative changes than non-soccer players. ARGP in soccer players was associated with central disc protrusion and higher grades of pubic BMO. Moreover, positive MRI findings were significantly more frequent in soccer players compared with non-soccer players irrespective of symptoms, suggesting that these MRI changes may be associated with soccer play itself rather than clinical symptoms. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Brito, João; Fontes, Ivo; Ribeiro, Fernando
To investigate the effects of an official soccer match on postural stability in youth elite soccer players.......To investigate the effects of an official soccer match on postural stability in youth elite soccer players....
Full Text Available The purpose of the study was to find out the relationship between psychological variables and soccer playing ability among the university level male players. 42 soccer players representing different universities who participated in inter university competitions were selected as the subjects of the study. The dependent variable was soccer playing ability and independent variables were the selected psychological variables. Soccer playing ability was determined through a 10 point scale at the time of competitions. Psychological variables included achievement motivation, anxiety, self-concept and aggression. The data was statistically analyzed using Karl Pearson’s correlation coefficient and multiple regression analysis using SPSS. It was concluded that soccer playing ability has a positive correlation with achievement motivation and self-concept whereas anxiety and aggression have a negative correlation with soccer playing ability.
Heading occur frequently in soccer games and studies have shown that repetitive heading of the soccer ball could result in degeneration of brain cells and lead to mild traumatic brain injury. This study proposes a two degree-of-freedom linear mathematical model to study the impact of the soccer ball on the brain. The model ...
Full Text Available Soccer referees enforce the laws of the game and the decisions they make can directly affect match results. Fixtures within European competitions take place in climatic conditions that are often challenging (e.g. Moscow ~ -5oC, Madrid ~30oC. Effects of these temperatures on player performance are well documented; however, little is known how this environmental stress may impair cognitive performance of soccer referees and if so, whether exercise exasperates this. The present study aims to investigate the effect of cold (COLD; 5oC, 40% relative humidity (RH, hot (HOT; 30oC, 40% RH and temperate (CONT; 18oC, 40% RH conditions on decision making during soccer specific exercise. On separate occasions within each condition, thirteen physically active males; either semi-professional referees or semi-professional soccer players completed three 90 min intermittent treadmill protocols that simulated match play, interspersed with 4 computer delivered cognitive tests to measure vigilance and dual task capacity. Core and skin temperature, heart rate, rating of perceived exertion and thermal sensation were recorded throughout the protocol. There was no significant difference between conditions for decision making (p > 0.05 despite significant differences in measured physiological variables (skin temperature = HOT 34.5 ± 5.1°C; CONT 31.2 ± 0.1°C and COLD 26.7 ± 0.5°C; p < 0.05. It is hypothesised that the lack of difference observed in decision making ability between conditions was due to the exercise protocol used, as it may not have elicited an appropriate and valid soccer specific internal load to alter cognitive functioning.
Van Yperen, N.W.
This study investigated whether the perception of disadvantageous inequity makes athletes more vulnerable to dropping out. Sixty five talented youth male soccer players (mean age = 16.6 years), attending a prestigious soccer school, completed a questionnaire at the beginning and at the end of the
Kiliç, Ö; Aoki, H.; Goedhart, E.; Hägglund, M.; Kerkhoffs, G. M. M. J.; Kuijer, P. P. F. M.; Waldén, M.; Gouttebarge, V.
Psychological factors have shown to be predictors of injury in professional football. However, it seems that this is a two-way relationship, as severe musculoskeletal time-loss injuries have shown to be associated with the onset of symptoms of common mental disorders (CMD). There is no longitudinal
Lemmink, K A P M; Verheijen, R; Visscher, C
The purpose of this study was to examine the discriminative power of the recently developed Interval Shuttle Run Test (ISRT) and the widely used Maximal Multistage 20 m Shuttle Run Test (MMSRT) for soccer players at different levels of competition. The main difference between the tests is that the exercise mode of the ISRT is not continuous but intermittent. Instead of 60 s of running per stage in the MMSRT, 30 s of running are alternated with 15 s of walking, twice per stage. Comparative study: within a 2-week period, 81 male soccer players at the Dutch premier league professional, premier league and 3rd division amateur levels performed the ISRT and the MMSRT. The total number of runs was scored for both tests. Only the ISRT distinguished between levels of competition. In general, the ISRT correlated moderately with the MMSRT for players of different levels of competition (rP: 0.52-0.83). In contrast to the MMSRT, the ISRT shows discriminative power for soccer players at different levels of competition supporting the validity of the ISRT for measuring endurance in a more soccer-specific way. As a result of the intermittent character of the ISRT the energetics of the ISRT and the MMSRT are not closely related.
The purpose of this study was to examine the relationship of the performance of male amateur soccer players on tests of field dependence/independence and soccer-specific decision-making tests. The relationships between the participants' (N = 14) accuracy, and speed of decision, on simple and complex soccer decision-making tests; scores on Parts B or C of the Group Embedded Figures Test under normal conditions: scores on Parts B or C of the Group Embedded Figures Test when timed; and time taken to complete the timed condition of the Group Embedded Figures Test were examined. There were no significant correlations between performance on the soccer specific tests and the tests of field dependence/independence.
Lollo, Pablo Christiano Barboza; Amaya-Farfan, Jaime; de Carvalho-Silva, Luciano Bruno
.... This study was designed to compare the effects produced by three types of protein supplements on body composition, biochemical parameters and performance of a top Brazilian professional soccer team...
Kiliç, Ö; Aoki, H; Goedhart, E; Hägglund, M; Kerkhoffs, G M M J; Kuijer, P P F M; Waldén, M; Gouttebarge, V
Psychological factors have shown to be predictors of injury in professional football. However, it seems that this is a two-way relationship, as severe musculoskeletal time-loss injuries have shown to be associated with the onset of symptoms of common mental disorders (CMD). There is no longitudinal study performed exploring this interaction between symptoms of CMD and injuries. The purpose of this study was to explore the interaction between severe musculoskeletal time-loss injuries and symptoms of CMD in professional football players over a 12-month period. Players were recruited by their national players' unions in five European countries. Symptoms of CMD included in the study were related to distress, anxiety/depression, sleep disturbance and adverse alcohol use. A total of 384 professional football players were enrolled in the study, of whom 262 (68%) completed the 12-month follow-up period. The mean age of the participants at baseline was 27 ± 5 years, and they had played professional football for 8 ± 5 years on average. Symptoms of CMD at baseline were not associated with the onset of severe musculoskeletal time-loss injuries during the follow-up period with relative risks (and 95% CI) ranging from 0.6 (0.3-1.0) to 1.0 (0.5-2.2). In contrast, severe musculoskeletal time-loss injuries reported at baseline were associated with the onset of symptoms of CMD during the follow-up period with relative risks ranging from 1.8 (0.8-3.7) to 6.9 (4.0-11.9). No relationship was found between symptoms of CMD and the onset of severe musculoskeletal time-loss injuries. However, professional football players who suffered from severe musculoskeletal time-loss injuries are likely to develop subsequent symptoms of CMD. This study emphasizes the need for an interdisciplinary medical approach, which not only focuses on the physical but also on the mental health of professional football players. An early identification of players at risk of symptoms of CMD, such as those
Relação entre torque extensor e relação I: Q com salto unipodal triplo horizontal em jogadores profissionais de futebol Relationship between extensor torque and H: Q ratio with triple hop distance in professional soccer players
Luiz Fernando Approbato Selistre
Full Text Available OBJETIVOS: 1 Determinar e comparar o torque extensor, relação I:Q e distância do salto triplo entre os membros; 2 identificar a relação entre o torque extensor e relação I:Q com o desempenho no salto triplo em jogadores profissionais de futebol. MATERIAIS E MÉTODOS: Foram selecionados 21 indivíduos, homens, idade média de 23,2 anos (± 3,6, saudáveis, sem histórico de lesões, praticantes profissionais de futebol. Os atletas foram avaliados em um dinamômetro isocinético nas velocidades de 60, 180 e 300°/s, das quais foram obtidos os picos de torque e calculada a relação I:Q nas três velocidades. Foi realizada também a avaliação funcional por meio do salto unipodal triplo horizontal, e desse foi obtida a distância saltada em metros. RESULTADOS: Não houve diferença entre membros (dominante e não dominante para os testes (p = 0,23. Além disso, foi observada baixa correlação entre o torque extensor e teste funcional nas três velocidades (membro dominante: 60°/s_r = 0,38; 180°/s_r = 0,43*; 300°/s_r = 0,26. Membro não dominante: 60°/s_r = 0,36; 180°/s_r = 0,30; 300°/s_r = 0,48* (*p OBJECTIVE: The aims of this study were: 1 to determine and compare the extensor torque, H:Q ratio and triple hop distance in functional test between lower extremities; 2 to identify the relationship between extensor torque and H:Q ratio with the performance in triple hop distance in professional soccer players. MATERIALS AND METHODS: Twenty-one healthy male professional soccer players, average 23.2 (± 3.6 years old, without history of injury were selected. The athletes were assessed in an isokinetic dynamometer at three angular velocities: 60, 180 and 300°/s, and from this assessment the peak of torque and calculated H:Q ratio at the three velocities were obtained. The triple hop distance was also used to calculate the hopped distance in meters. RESULTS: No significant difference was found between the lower extremities (dominant and non
Selmi, Mohamed Amin; Al-Haddabi, Badriya; Yahmed, Mohamed Haj; Sassi, Radhouane Haj
The purpose of this study is to examine the relationship between repeated-sprint sets (RSS) performance indices and anaerobic speed reserve (ASR) in young soccer players of different maturity status. One hundred and seventy nine young male soccer players (11.1 to 17.8 years) classified as pre- (n=50), circum- (n=60), or post- (n=69) peak height velocity (PHV) performed multi-stage shuttle run test (MRST) to measure maximal aerobic speed (MAS), 30-m sprint with 10-m splits to estimate maximal anaerobic speed (MAnS), and RSS test. ASR was calculated as the difference between MAS and MAnS. The RSS indices, MAS, MAnS and ASR were significantly different in the three maturity groups (pRSS performance indices and ASR varied considerably depending on maturity status. Very large correlations between ASR and RSS indices expressed as sum sprint time (SST) and best sprint time (BST) were found for pre- and circum-PHV groups (r=-0.76, -0.79 and r=-0.82, -0.86, respectively). In the post-PHV group, ASR was moderately associated with both SST (r=-0.45) and BST (r=-0.46). To sum up, these results highlighted that the ASR is more related to factors of RSS performance in pre- and circum-PHV male soccer players compared with post-PHV ones. These findings could help coaches and strength and conditioning professionals to better understand how the relationship between ASR and RSS evolve across the maturity and may be considered, therefore, useful in youth soccer selection/training process.
Bendiksen, Mads; Bischoff, Rasmus; Randers, Morten B
INTRODUCTION: The aims of the study were 1) to evaluate whether a multifaceted simulated soccer game protocol, entitled the Copenhagen Soccer Test (CST), elicited a similar physiological loading as a competitive game (CG) and 2) to determine muscle metabolites, blood variables, and sprint...... performance in various phases of CST. METHODS: Twelve Danish Second- and Third-Division soccer players participated in the study. On separate days, HR measurements, frequent blood sampling, and physical/technical tests were performed during 60- and 90-min versions of the CST during which repeated musculus...... CST (5.2 ± 0.6 to 4.9 ± 0.7 m·s). CONCLUSIONS: The physiological response to the CST was reproducible and comparable to that of high-level CG. The CST allowed for rapid muscle sampling and revealed high creatine phosphate degradation throughout the test and a lowered glycogen utilization toward...
Delaney, J Scott; Al-Kashmiri, Ammar; Correa, José A
To examine the mechanisms of injury for concussions in university football, ice hockey, and soccer. Prospective cohort design. McGill University Sport Medicine Clinic. Male and female athletes participating in varsity football, ice hockey, and soccer. Athletes were followed prospectively over a 10-year period to determine the mechanisms of injury for concussions and whether contact with certain areas of the body or individual variables predisposed to longer recovery from concussions. For soccer, data were collected on whether concussions occurred while attempting to head the ball. There were 226 concussions in 170 athletes over the study period. The side/temporal area of the head or helmet was the most common area to be struck resulting in concussion in all 3 sports. Contact from another player's head or helmet was the most probable mechanism in football and soccer. In hockey, concussion impacts were more likely to occur from contact with another body part or object rather than another head/helmet. Differences in mechanisms of injuries were found between males and females in soccer and ice hockey. Athletes with multiple concussions took longer to return to play with each subsequent concussion. Half of the concussions in soccer were related to attempting to head the soccer ball. The side of the head or helmet was the most common area to be struck resulting in concussion in all 3 sports. In ice hockey and soccer, there are differences in the mechanisms of injury for males and females within the same sport.
Skordilis, E K; Gavriilidis, A; Charitou, S; Asonitou, K
To examine the differences in sport achievement orientation among 35 professional, 36 amateur, and 35 wheelchair basketball athletes, these men completed three subscales of Competitiveness, Win orientation, and Goal orientation of the 25-item Sport Orientation Questionnaire. A multivariate analysis of variance indicated significant differences among groups. Win orientation was the factor, through discriminant function analysis, that significantly separated the athletes into the three groups. The highest win score was obtained by the professional, followed by the amateur and wheelchair groups. Replication study is necessary to confirm the present findings.
Aldous, Jeffrey W F; Akubat, Ibrahim; Chrismas, Bryna C R; Watkins, Samuel L; Mauger, Alexis R; Midgley, Adrian W; Abt, Grant; Taylor, Lee
This study investigated the reliability and validity of a novel nonmotorised treadmill (NMT)-based soccer simulation using a novel activity category called a "variable run" to quantify fatigue during high-speed running. Twelve male University soccer players completed 3 familiarization sessions and 1 peak speed assessment before completing the intermittent soccer performance test (iSPT) twice. The 2 iSPTs were separated by 6-10 days. The total distance, sprint distance, and high-speed running distance (HSD) were 8,968 ± 430 m, 980 ± 75 m and 2,122 ± 140 m, respectively. No significant difference (p > 0.05) was found between repeated trials of the iSPT for all physiological and performance variables. Reliability measures between iSPT1 and iSPT2 showed good agreement (coefficient of variation: 0.80). Furthermore, the variable run phase showed HSD significantly decreased (p ≤ 0.05) in the last 15 minutes (89 ± 6 m) compared with the first 15 minutes (85 ± 7 m), quantifying decrements in high-speed exercise compared with the previous literature. This study validates the iSPT as a NMT-based soccer simulation compared with the previous match-play data and is a reliable tool for assessing and monitoring physiological and performance variables in soccer players. The iSPT could be used in a number of ways including player rehabilitation, understanding the efficacy of nutritional interventions, and also the quantification of environmentally mediated decrements on soccer-specific performance.
Development of body composition, hormone profile, physical fitness, general perceptual motor skills, soccer skills and on-the-ball performance in soccer-specific laboratory test among adolescent soccer players.
Vänttinen, Tomi; Blomqvist, Minna; Häkkinen, Keijo
The aim of the present study was to examine the development of on-the-ball skills in soccer-specific laboratory test and to examine how traditional measures of body composition, hormone profile, physical fitness, general perceptual motor skills and soccer skills were related to performance measured in open skill environment among 10, 12, and 14-year-old regional male soccer players (n = 12/group). The measured variables were height, weight, fat, muscle mass, testosterone, 10m sprint, agility, counter movement jump, peripheral awareness, Eye- Hand-Foot coordination, passing skill, dribbling skill and on-the-ball skills (performance time and passing accuracy) in soccer-specific laboratory test. A significant main effect by age was found in all measured variables except in fat, in peripheral awareness and in passing accuracy. In discriminant analysis 63.9% (λ = 0.603, F = 4.600, p motor skills into three ability groups originally classified with performance time in soccer-specific laboratory test. Correlation co- efficient analysis with-in age groups revealed that variables associated with performance time in soccer-specific laboratory test were peripheral awareness (r = 0.72, p anticipation time and performance time in soccer- specific laboratory test was significant only in the 14-year-old age group (r = 0.76, p motor skills less important with age in soccer-specific laboratory test. Key pointsPhysical fitness characteristics and general perceptual motor skills predicted performance time of the open skill soccer-specific laboratory test in the group of 10-14 year-old regional soccer players.Before puberty the players were able to compensate weaker soccer-specific skills with better general physical performance abilities.Soccer-specific skills became more important with age and at the age of 14 the players were not able to compensate soccer-specific skills with general physical performance abilities.Beside basic ball-handling skills it also important to recognize
Full Text Available Relative Age Effect (RAE is the breakdown by both age grouping and dates of birth of athletes. In the past 20 years the existence of this effect has been shown with higher or smaller impact in multiple sports, including soccer. The purpose of this study was to identify the existence of RAE in European soccer players. The sample included 841 elite soccer players who were participants in the UEFA European Soccer Championship in different categories. The professional category (n = 368, U-19 (n = 144 and U-17 (n = 145 were in 2012, and U-21 was in 2011 (n = 184. The Kolmogorov-Smirnov test and the Levene test recommended the use of nonparametric statistics. The results obtained by the square test (the Kruskal-Wallis test and Cohen’s effect sizes revealed the existence of RAE (χ2 = 17.829, p < 0.001; d = 0.30, with the size of their different effects depending on their category or qualifying round achieved by the national team and the existence of significance in the observed differences by category. Therefore, we could continue examining RAE which is present in elite soccer, and could be considered a factor that influences performance of the national teams tested. RAE was not evident in the professional teams analysed, however it was present in the three lower categories analysed (youth categories, with its influence being greater on younger age categories (U-17.
Fabregat-Andres, Oscar; Munoz-Macho, Adolfo; Adell-Beltran, Guillermo; Ibanez-Catala, Xavier; Macia, Agustin; Facila, Lorenzo
Background Prevention of cardiac events during competitive sports is fundamental. New technologies with remote monitoring systems integrated into clothing could facilitate the screening of heart disease. Our aim was to evaluate the feasibility of Nuubo system during a field stress test performed by soccer players, comparing results with treadmill ergospirometry as test reference. Methods Nineteen male professional soccer players (19.2 ± 1.6 years) were studied. Wireless electrocardiographic monitoring during a Yo-Yo intermittent recovery test level 1 in soccer field and subsequent analysis of arrhythmias were firstly performed. Subsequently, in a period no longer than 4 weeks, each player underwent cardiopulmonary exercise testing in hospital. Results During Yo-Yo test, electrocardiogram (ECG) signal was interpretable in 16 players (84.2%). In the other three players, ECG artifacts did not allow a proper analysis. Estimation of maximum oxygen consumption was comparable between two exercise tests (VO2 max 53.3 ± 2.4 vs. 53.7 ± 3.0 mL/kg/min for Yo-Yo test and ergometry respectively; intra-class correlation coefficient 0.84 (0.63 - 0.93), P < 0.001). No arrhythmias were detected in any player during both tests. Conclusions The use of Nuubo’s technology allows an accurate single-lead electrocardiographic recording and estimation of reliable performance variables during exercise testing in field, and provides a new perspective to cardiac remote monitoring in collective sports. PMID:28348705
Reynolds, Bryson B.; Patrie, James; Henry, Erich J.; Goodkin, Howard P.; Broshek, Donna K.; Wintermark, Max; Druzgal, T. Jason
Background: The effects of head impact in sports are of growing interest for clinicians, scientists, and athletes. Soccer is the most popular sport worldwide, but the burden of head impact in collegiate soccer is still unknown. Purpose: To quantify head impact associated with practicing and playing collegiate soccer using wearable accelerometers. Study Design: Descriptive epidemiological study. Methods: Mastoid patch accelerometers were used to quantify head impact in soccer, examining differences in head impact as a function of sex and event type (practice vs game). Seven female and 14 male collegiate soccer players wore mastoid patch accelerometers that measured head impacts during team events. Data were summarized for each athletic exposure, and statistical analyses evaluated the mean number of impacts, mean peak linear acceleration, mean peak rotational acceleration, and cumulative linear and rotational acceleration, each grouped by sex and event type. Results: There were no differences in the frequency or severity of head impacts between men’s and women’s soccer practices. For men’s soccer, games resulted in 285% more head impacts than practices, but there were no event-type differences in mean impact severity. Men’s soccer games resulted in more head impacts than practices across nearly all measured impact severities, which also resulted in men’s soccer games producing a greater cumulative impact burden. Conclusion: Similar to other sports, men’s soccer games have a greater impact burden when compared with practices, and this effect is driven by the quantity rather than severity of head impacts. In contrast, there were no differences in the quantity or severity of head impacts in men’s and women’s soccer practices. These data could prompt discussions of practical concern to collegiate soccer, such as understanding sex differences in head impact and whether games disproportionately contribute to an athlete’s head impact burden. PMID:28491885
This paper evaluates and describes themes surrounding the subjective perceptions of success in players and coaches at a professional South African soccer club. Literature around this topic is limited, particularly concerning the qualitative understandings of South African sportsmen and women, providing ample motivation ...
Bekkers, J.E.J.; de Windt, Th.S.; Brittberg, M.
The prevalence of focal articular cartilage lesions among athletes is higher than in the general population. Treatment goals differ considerably between the professional and recreational athlete. High financial stakes and the short duration of a professional career influence the treatment selection for the professional athlete, while such parameters weigh differently in recreational sports. This article describes our investigation of the relation between sports and a high prevalence of focal cartilage lesions. In addition, we provide a critical review of the best available evidence for cartilage surgery and treatment selection, evaluate specific patient profiles for professional and recreational athletes, and propose a treatment algorithm for the treatment of focal cartilage lesions in football (soccer) players. PMID:26069606
Ludewig, Revital; LaLlave, Juan
This chapter contributes towards understanding the effect of gender on judging. It examines whether the experiences of women and men judges with their profession support a gender differences or a gender similarities hypothesis. Women and men judges in Switzerland (N = 243) were asked to rank their experiences with professional difficulties, coping strategies, work-life balance, satisfaction and discrimination to determine whether there were differences or similarities due to gender. Significa...
Salustowicz, R.; Wiering, M.A.; Schmidhuber, J.
We use simulated soccer to study multiagent learning. Each team's players (agents) share action set and policy but may behave differently due to position-dependent inputs. All agents making up a team are rewarded or punished collectively in case of goals. We conduct simulations with varying
Salustowicz, R.; Wiering, M.A.; Schmidhuber, J.
We study multiagent learning in a simulated soccer scenario. Players from the same team share a common policy for mapping inputs to actions. They get rewarded or punished collectively in case of goals. For varying team sizes we compare the following learning algorithms: TD-Q learning with
Soccer, or football as it is called in the rest of the world, is the most popular and fastest-growing global sport, with an estimated 240 million people regularly playing what Brazilian star Pele called "the beautiful game." Millions, worldwide, watch it on television. In 2006, the average viewership for each match of the month-long World Cup was…
Andersen, Thomas Bull; Dörge, Henrik C.; Thomsen, Franz Ib
An equation to describe the velocity of the soccer ball after the collision with a foot was derived. On the basis of experimental results it was possible to exclude certain factors and only describe the angular momentum of the system, consisting of the shank, the foot and the ball, leading...
Jordet, Geir; Elferink-Gemser, Marije T.
This study was designed to capture the first-hand experiences of stressors, coping, and emotions that elite professional soccer players have during a major soccer penalty shootout. Eight players who each took part in an important European Championships penalty shootout were interviewed. The results
Full Text Available The purpose of this study was to investigate the effects of loaded and unloaded plyometric training strategies on speed and power performance of elite young soccer players. Twenty-three under-17 male soccer players (age: 15.9 ± 1.2 years, height: 178.3 ± 8.1 cm, body-mass (BM: 68.1 ± 9.3 kg from the same club took part in this study. The athletes were pair-matched in two training groups: loaded vertical and horizontal jumps using an haltere type handheld with a load of 8% of the athletes' body mass (LJ; n = 12 and unloaded vertical and horizontal plyometrics (UJ; n = 11. Sprinting speeds at 5-, 10-, and 20-m, mean propulsive power (MPP relative to the players' BM in the jump squat exercise, and performance in the squat jump (SJ and countermovement jump (CMJ were assessed pre- and post-training period. During the experimental period, soccer players performed 12 plyometric training sessions across a 6-week preseason period. Magnitude based inferences and standardized differences were used for statistical analysis. A very likely increase in the vertical jumps was observed for the LJ group (99/01/00 and 98/02/00 for SJ and CMJ, respectively. In the UJ group a likely increase was observed for both vertical jumps (83/16/01 and 90/10/00, for SJ and CMJ, respectively. An almost certainly decrease in the sprinting velocities along the 20-m course were found in the LJ group (00/00/100 for all split distances tested. Meanwhile, in the UJ likely to very likely decreases were observed for all sprinting velocities tested (03/18/79, 01/13/86, and 00/04/96, for velocities in 5-, 10-, and 20-m, respectively. No meaningful differences were observed for the MPP in either training group (11/85/04 and 37/55/08 for LJ and UJ, respectively. In summary, under-17 professional soccer players increased jumping ability after a 6-week preseason training program, using loaded or unloaded jumps. Despite these positive adaptations, both plyometric strategies failed to
Callum G. Brownstein
Full Text Available Aim: Previous research into the etiology of neuromuscular fatigue following competitive soccer match-play has primarily focused on peripheral perturbations, with limited research assessing central nervous system function in the days post-match. The aim of the present study was to examine the contribution and time-course of recovery of central and peripheral factors toward neuromuscular fatigue following competitive soccer match-play.Methods: Sixteen male semi-professional soccer players completed a 90-min soccer match. Pre-, post- and at 24, 48, and 72 h participants completed a battery of neuromuscular, physical, and perceptual tests. Maximal voluntary contraction force (MVC and twitch responses to electrical (femoral nerve and transcranial magnetic stimulation (TMS of the motor cortex during isometric knee-extension and at rest were measured to assess central nervous system (voluntary activation, VA and muscle contractile (potentiated twitch force, Qtw, pot function. Electromyography responses of the rectus femoris to single- and paired-pulse TMS were used to assess corticospinal excitability and short-interval intracortical inhibition (SICI, respectively. Fatigue and perceptions of muscle soreness were assessed via visual analog scales, and physical function was assessed through measures of jump (countermovement jump height and reactive strength index and sprint performance.Results: Competitive match-play elicited significant post-match declines in MVC force (−14%, P < 0.001 that persisted for 48 h (−4%, P = 0.01, before recovering by 72 h post-exercise. VA (motor point stimulation was reduced immediately post-match (−8%, P < 0.001, and remained depressed at 24 h (−5%, P = 0.01 before recovering by 48 h post-exercise. Qtw,pot was reduced post-match (−14%, P < 0.001, remained depressed at 24 h (−6%, P = 0.01, before recovering by 48 h post-exercise. No changes were evident in corticospinal excitability or SICI. Jump performance
Loturco, Irineu; Pereira, Lucas A.; Kobal, Ronaldo; Kitamura, Katia; Ramírez-Campillo, Rodrigo; Zanetti, Vinicius; Abad, Cesar C. Cal; Nakamura, Fabio Y.
Tensiomyography (TMG) has been used as a simple and non-invasive tool to assess the mechanical properties of skeletal muscles. The TMG-derived velocity of contraction (Vc), which can be calculated from the ratio between maximal radial displacement and the sum of contraction time and delay time, has been proposed for evaluating athletes. However, its sensitivity to training effects and possible relation with changes in soccer players’ neuromuscular performance have not yet been addressed. To test this possibility, twenty-two male Brazilian elite soccer players were assessed using TMG-derived Vc, unloaded squat jump, countermovement jump and drop jump at 45 cm, loaded jump squat and linear (20 m) and change of direction (COD) sprint tests, prior to and after an 8-week period, between two consecutive official tournaments, during which the concurrency between endurance and strength-power training commonly impairs neuromuscular capacities. Magnitude-based inference was used to detect meaningful training effects. From pre- to post-tests, it was observed likely to almost certainly improvements in all modes of jumping tests. In addition, we could verify decrements in the 20-m and COD sprint performances, which were rated as very likely and almost certainly, respectively. Finally, both rectus femoris and biceps femoris muscles presented a likely reduction in Vc. Therefore, chronic decreases in sprinting speed are possibly accompanied by a reduced TMG-derived Vc. From a practical standpoint, the TMG-derived Vc can be used to monitor negative specific-soccer training effects related to potential impairments in maximum speed. Key points Tensiomyography (TMG) can be considered a useful technology for coaches and sport scientists seeking for non-invasive and practical tools to assess the muscle function of elite athletes; Velocity of contraction (Vc) is a single index able to integrate several of the reliable mechanical outcomes provided by TMG, which was shown to be sensitive
Full Text Available PURPOSE: To determine the volume and degree of asymmetry of iliopsoas (IL and gluteal muscles (GL in tennis and soccer players. METHODS: IL and GL volumes were determined using magnetic resonance imaging (MRI in male professional tennis (TP and soccer players (SP, and in non-active control subjects (CG (n = 8, 15 and 6, respectively. RESULTS: The dominant and non-dominant IL were hypertrophied in TP (24 and 36%, respectively, P<0.05 and SP (32 and 35%, respectively, P<0.05. In TP the asymmetric hypertrophy of IL (13% greater volume in the non-dominant than in the dominant IL, P<0.01 reversed the side-to-side relationship observed in CG (4% greater volume in the dominant than in the contralateral IL, P<0.01, whilst soccer players had similar volumes in both sides (P = 0.87. The degree of side-to-side asymmetry decreased linearly from the first lumbar disc to the pubic symphysis in TP (r = -0.97, P<0.001, SP (r = -0.85, P<0.01 and CG (r = -0.76, P<0.05. The slope of the relationship was lower in SP due to a greater hypertrophy of the proximal segments of the dominant IL. Soccer and CG had similar GL volumes in both sides (P = 0.11 and P = 0.19, for the dominant and contralateral GL, respectively. GL was asymmetrically hypertrophied in TP. The non-dominant GL volume was 20% greater in TP than in CG (P<0.05, whilst TP and CG had similar dominant GL volumes (P = 0.14. CONCLUSIONS: Tennis elicits an asymmetric hypertrophy of IL and reverses the normal dominant-to-non-dominant balance observed in non-active controls, while soccer is associated to a symmetric hypertrophy of IL. Gluteal muscles are asymmetrically hypertrophied in TP, while SP display a similar size to that observed in controls. It remains to be determined whether the different patterns of IL and GL hypertrophy may influence the risk of injury.
Leone, James E; Mullin, Elizabeth M; Maurer-Starks, Suanne S; Rovito, Michael J
The purpose of this study was to determine whether there is evidence of reliability and validity for the Adolescent Body Image Satisfaction Scale (ABISS), an instrument previously developed to measure adolescent body image. A sample (N = 330) of adolescent males, aged 14-19 years, completed the ABISS to determine current body image satisfaction. Data were analyzed for measures of instrument composite reliability and initial content and construct validity. Exploratory factor analysis supported a 3-factor solution (16 total items), which explained 42.7% of variance in the model. Composite reliability for the subscales, body competence, body inadequacy, and internal conflict ranged from 0.64 to 0.82. Exploratory factor analysis of the ABISS provides initial psychometric support for a valid and reliable measure for assessing adolescent male body image, which also can be used as a needs assessment tool. Strength and conditioning professionals should be aware of their athlete and client psychological attributes, many of whom are adolescents. Understanding how adolescents view their bodies and their body image will assist professionals in designing appropriate, health-promotive strength programs, while at the same time monitoring for signs of body image dissatisfaction. Assessing body image can help heighten awareness and possibly encourage preventative programming to help avert negative health practices (e.g., performance-enhancing drug use, exercise addictions, disordered eating). The ABISS seems to have preliminary psychometric support to be a valid and reliable instrument that helps gauge at-risk populations.
Farquharson, Claire; Greig, Matt
To investigate the efficacy of kinesiology taping in mediating the influence of fatigue on ankle sprain risk, 12 male soccer players completed single-leg dynamic balance trials pre- and post-exercise (soccer-specific protocol, isokinetic ankle inversion/eversion protocol) in each of three counter-balanced taping conditions (no tape, zinc oxide tape ZO, kinesiology tape KT). Balance was quantified as the overall stability index (OSI) and directional stability indices of platform deflection. Soccer-specific fatigue only increased OSI in the no tape condition (p = 0.03), with ZO and KT trials negating a fatigue affect. Localized fatigue increased OSI in the no tape (p = 0.01) and ZO (p = 0.05) trials, with no increase in the KT trial. A similar pattern was observed in medio-lateral and anterio-posterior balance indices. KT mediates soccer-simulated and local peroneal fatigue, with practical implications for epidemiological observations of increased injury risk during the latter stages of match play.
Full Text Available This contribution presents a part of the results of the research project entitled “Stereotipi di genere, relazioni educative e infanzie” (“Gender stereotypes, educational relationships and childhood" conducted between 2010 and 2012 by a group of researchers from the CSGE Centre for Gender and Education Studies at the Department of Education Studies, funded by the Emilia-Romagna Region. The purpose of the research was to measure the ideas and representations of gender and the relations between genders in adults who are educationally (and emotionally significant for preschool children (0-6 years and to foster widespread thought on the issue of the stereotyped images of the female and male identity that still exist and are transmitted from a very early age. In particular this article presents the focus of the analysis of the presence of males from the parents' point of view.
Full Text Available In Brazil soccer has assumed a role beyond a simple sports modality by becoming a social phenomenon. Historically soccer is perceptible from two different perspectives: as a means of transmitting ideology and as an important element of Brazilian culture. The aim of this bibliographical study is to discuss soccer as a cultural manifestation and, at some historical moments, as a mean of transmitting ideology. This discussion made it possible to notice that soccer provides subsidies for a better understanding of organizational and relational forms that permeate Brazilian society.
Jensen, Anker; Kaerlev, Linda; Tüchsen, Finn
OBJECTIVE: High risks for locomotor diseases have been reported for bus and truck drivers in general; however, little is known about the specific risks of long-haul truck drivers. METHODS: Standardised hospitalisation ratios (SHR) for different locomotor diseases of bus drivers, long-haul truck...... drivers and other truck drivers were compared with each other and with the general Danish working population. RESULTS: Intervertebral disc disorders were more common among professional drivers (SHR: 119, 95% CI: 114-125) and of similar magnitude for cervical and non-cervical disorders. Both long......-haul truck drivers and bus drivers had higher SHR for intervertebral disc disorders (SHR: 133, 95% CI: 114-155/SHR: 141, 95% CI: 129-154, respectively) than other truck drivers (SHR: 109, 95% CI: 102-116). The SHR for carpal tunnel syndrome was high among long-haul drivers (SHR: 163, 95% CI: 101...
Lubiatowski, Przemyslaw; Kaczmarek, Piotr; Cisowski, Pawel; Breborowicz, Ewa; Grygorowicz, Monika; Dzianach, Marcin; Krupecki, Tomasz; Laver, Lior; Romanowski, Leszek
Glenohumeral range of motion adaptations may affect throwing athletes and contribute to shoulder injury. The purpose of this study was to evaluate shoulder rotation deficits among elite professional handball players and its correlation to the presence of shoulder pain and morphological changes. Eighty-seven elite professional handball players and 41 healthy non-athlete volunteers participated in the study. Evaluations included measurement of range of internal and external rotation, total arch of motion, identification of shoulder pain and ultrasound scan for diagnosis of rotator cuff tears and internal impingement. Glenohumeral rotational deficits (>20-25°) were found among 11 players group (13%). The throwing shoulders in the players group showed a decrease in internal rotation and an increase in external rotation with significantly larger ranges among players compared to the non-athlete group. Internal rotation deficit >20° was associated with higher incidence of shoulder pain among players. Both internal rotation deficits (>25°) and total arch of motion deficit (>20°) co-existed with higher incidence of internal impingement. Shoulder pain was common (36/97-41%) and was associated with decreased external rotation and total arch of motion. Internal impingement (found in 13/87-15%) correlated with decreased rotation ranges and a greater deficit in total arch of motion, whereas higher gain in external rotation correlated with a partial rotator cuff tear (found in 12/87-14%). Shoulder pathologies and problems commonly affected the group of handball players. Greater glenohumeral rotational deficits in throwing shoulders of handball players correlate with shoulder pain and internal impingement, while increased external rotation with partial rotator cuff tears. Such deficits affect 13% of the athlete population. Major clinical relevance of the study is to monitor handball players' shoulders both clinically and by proper imaging. Evaluation of range of rotation seems
Daniel Barbosa Coelho
Full Text Available Soccer is a sport practiced worldwide, on all continents. It is considered an intermittent activity of high intensity and long duration, in which movements that require great strength and speed, such as jumps and sprints, result in high levels of muscle microtrauma, hampering athletes’ training and recovery. The present study aimed to evaluate the magnitude of changes in different markers of physiological demand resulting from a soccer match in healthy individuals. Ten healthy male physical education students participated in the study and were evaluated in two matches: the semi-final and final games of the college tournament at the federal university where they studied. Blood samples were collected from each volunteer pre- and post-match. Cortisol, IL-6 and CK concentrations were increased after the match (p < 0.05. Testosterone and alpha-actin concentrations did not change. Our results indicate that changes in some of the acute response markers evaluated in players before and after competitive soccer matches provide important information for planning training or recovery, as well as nutritional strategies for improving performance.
Daniel Barbosa Coelho
Full Text Available DOI: http://dx.doi.org/10.5007/1980-0037.2013v15n6p667 Soccer is a sport practiced worldwide, on all continents. It is considered an intermittent activity of high intensity and long duration, in which movements that require great strength and speed, such as jumps and sprints, result in high levels of muscle microtrauma, hampering athletes’ training and recovery. The present study aimed to evaluate the magnitude of changes in different markers of physiological demand resulting from a soccer match in healthy individuals. Ten healthy male physical education students participated in the study and were evaluated in two matches: the semi-final and final games of the college tournament at the federal university where they studied. Blood samples were collected from each volunteer pre- and post-match. Cortisol, IL-6 and CK concentrations were increased after the match (p < 0.05. Testosterone and alpha-actin concentrations did not change. Our results indicate that changes in some of the acute response markers evaluated in players before and after competitive soccer matches provide important information for planning training or recovery, as well as nutritional strategies for improving performance.
Reilly, Thomas; Ball, David
To establish the net energy cost of dribbling a soccer ball, eight males ran on a treadmill while dribbling a ball against a rebound box. Oxygen uptake, perceived exertion, and blood lactate levels were measured and compared with results from subjects running without dribbling. Results are discussed. (Author/DF)
Objective. To investigate the effectiveness of accelerated rehabilitation and accelerated hydrotherapy after anterior cruciate ligament (ACL) reconstruction in male athletes participating in soccer. Design. A non-concurrent single subject, multiple baseline design (ABA design) was conducted over 10 weeks. A series of three ...
Male teamsport athletes have traditionally been described as some of the most homophobic and femphobic men in North American culture. However, in this ethnographic research of an education-based soccer team at a small Catholic university in a rural part of Middle America, I use inclusive masculinity theory to highlight that a softer version of…
The purpose of this study was to determine the contribution of selected stressors to the level of stress experienced by South African soccer officials. Forty-two South African Football Association (SAFA) accredited officials, attending a training camp in Potchefstroom, participated in this study. The group comprised of 40 male ...
Sutcliffe, Siobhan; Kawachi, Ichiro; Alderete, John F.; Gaydos, Charlotte A.; Jacobson, Lisa P.; Jenkins, Frank J.; Viscidi, Raphael P.; Zenilman, Jonathan M.; Platz, Elizabeth A.
Objective Several epidemiologic studies have investigated sexually transmitted infections (STIs) and later risk of genitourinary conditions with suggestive positive results. While these results may reflect causal associations, other possible explanations include confounding by factors possibly related to both STI acquisition and genitourinary condition risk, such as recognized STI risk factors/correlates, and other factors not typically considered in relation to STIs (e.g., general health-related behaviors or markers of such behaviors). Very few of these factors have been investigated in older populations in which STIs and genitourinary conditions are typically studied. Therefore, we investigated STI history correlates in one such population, the Health Professionals Follow-up Study. Methods We ascertained histories of potential correlates, and gonorrhea and syphilis by questionnaire (n=36,032), and performed serologic testing for Chlamydia trachomatis, Trichomonas vaginalis, human papillomavirus, and human herpesvirus type 8 infection in a subset (n=651). Results Positive correlations were observed for African-American race, foreign birth, southern residence, smoking, alcohol consumption, ejaculation frequency, vasectomy, and high cholesterol. Inverse correlations were observed for social integration and routine health-related examinations. Conclusions These findings provide useful information on potential confounders for epidemiologic investigations of STIs and chronic diseases, and interesting new hypotheses for STI prevention (e.g., STI counseling before vasectomy). PMID:19655261
Kim, Yong-Youn; Min, Kyoung-Ok; Choi, Jung-Hyun; Kim, Soon-Hee
[Purpose] The purpose of this study was to investigate differences in jumping ability and lower limb balance ability elicited by plyometric training and vibration exercise, of volleyball players with and without ankle injuries, which frequently occur among Korean professional volleyball players. [Subjects and Methods] Twenty-eight volleyball players were divided into the following groups: plyometric with ankle injury (PAI) group; plyometric with non-ankle injury (PAN) group; vibrator with ankle injury (VAI) group; and vibrator with non-ankle injury (VAN) group. After exercise and whole body vibration stimulation, their vertical jumping abilities, side step, and static equilibrium ability were measured. [Results] The vibration exercise group which had experienced ankle injuries showed significant improvements in the sidestep test after the intervention compared to before the intervention. In vertical jumping as well, significant improvements were observed in the VAI group and the VAN group following vibration exercise. In the balance ability test, significant improvesments in the PAN group and the PAI group were observed after the intervention. According to the results of the right side, there was significant change in the left/back side test and the right/back side test before and after the intervention; and in the test of one-leg standing with eyes closed, there were significant group, timing, and interaction effects. [Conclusions] The training method which effectively improved the jumping ability of volleyball players was plyometric training, and for balance ability improvement, whole body vibration exercise was effective.
Kim, Yong-Youn; Min, Kyoung-Ok; Choi, Jung-Hyun; Kim, Soon-Hee
[Purpose] The purpose of this study was to investigate differences in jumping ability and lower limb balance ability elicited by plyometric training and vibration exercise, of volleyball players with and without ankle injuries, which frequently occur among Korean professional volleyball players. [Subjects and Methods] Twenty-eight volleyball players were divided into the following groups: plyometric with ankle injury (PAI) group; plyometric with non-ankle injury (PAN) group; vibrator with ankle injury (VAI) group; and vibrator with non-ankle injury (VAN) group. After exercise and whole body vibration stimulation, their vertical jumping abilities, side step, and static equilibrium ability were measured. [Results] The vibration exercise group which had experienced ankle injuries showed significant improvements in the sidestep test after the intervention compared to before the intervention. In vertical jumping as well, significant improvements were observed in the VAI group and the VAN group following vibration exercise. In the balance ability test, significant improvesments in the PAN group and the PAI group were observed after the intervention. According to the results of the right side, there was significant change in the left/back side test and the right/back side test before and after the intervention; and in the test of one-leg standing with eyes closed, there were significant group, timing, and interaction effects. [Conclusions] The training method which effectively improved the jumping ability of volleyball players was plyometric training, and for balance ability improvement, whole body vibration exercise was effective. PMID:27313344
Scelles, Nicolas; Szymanski, Stefan; Dermit-Richard, Nadine
This paper examines insolvency at the highest levels of French soccer. Between 1970 and 2014 we observed 72 cases of insolvency arising from participation in the top two or three (since 1993) divisions. We find that demand (attendance) shocks can account for insolvency to a significant degree. We also find that insolvency can be explained by ownership structure, with the tradition Association form being more likely to lead to insolvency. We also examine the post-insolvency perf...
Rascle, Olivier; Traclet, Alan; Souchon, Nicolas; Coulomb-Cabagno, Genevieve; Petrucci, Carrie
The purpose of this study was to investigate the aggressor-victim difference in perceived legitimacy of aggression in soccer as a function of score information (tied, favorable, unfavorable), sporting penalization (no risk, yellow card, red card), and type of aggression (instrumental, hostile). French male soccer players (N = 133) read written…
Luiz Carlos Moraes
Full Text Available This study investigated the role of parents in the development of soccer players. Twenty parents and 12 soccer players, between 15 and 18 years old participated in the study. Both quantitative and qualitative approaches were used by administrating questionnaires forms and interviews. It was observed that few changes occurred in the family routines and that parents were minimally involved in their sons' sport activities. This did not appear to be a constraint for their sons' development because of their passion for soccer, the total amount of practice, and a potential lucrative professional career. Researchers should carefully adopt important paradigms from first world countries to another country with contextual differences.
Portas, Matthew David; Parkin, Guy; Roberts, James; Batterham, Alan Mark
The effect of maturity on Functional Movement Screen (FMS) scores in elite, adolescent soccer players was examined. A cross-sectional observational study was completed. Participants were 1163 male English Football League soccer players (age 8-18 years). Players were mid-foundation phase (MF) (U9); late foundation phase (LF) (U10 and U11); early youth development phase (EYD) (U12 and U13); mid-youth development (MYD) phase (U14-U15); Late Youth Development Phase (LYD) (U16) and early professional development phase (EPD) (U18). Age from peak height velocity was estimated and players were categorized as pre- or post-peak height velocity (PHV). To analyse where differences in FMStotal score existed we separated the screen into FMSmove (3 movement tests); FMSflex (2 mobility tests) and FMSstab (2 stability tests). FMStotal median score ranged from 11 at MF to 14 for EPD. There was a substantial increase (10%) in those able to achieve a score of ≥14 on FMStotal in those who were post-PHV compared to pre-PHV. This was explained by a substantial increase in those achieving a score of ≥4 on FMSstab (21%). There was a substantial increase in the proportion of players who achieved the FMStotal threshold of ≥14 with an increase of 47.5 (41.4-53.6)% from the MF phase to the EPD phase due to improvements in FMSmove and FMSstab. PHV and maturity have substantial effects on FMS performance. FMS assessment appears to be invalid for very young players. Findings are relevant to those analyzing movement in soccer players. Copyright © 2015 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.
Maria Luzete Costa Cavalcante
Full Text Available ABSTRACT OBJECTIVE: The present study aimed to evaluate the muscle fatigue of the quadriceps muscle in high-performance soccer players undergoing (anterior cruciate ligament ACL reconstruction. METHODS: We evaluated 17 high-performance soccer players from three professional soccer teams of a state in Brazil from August 2011 to July 2012. All subjects were evaluated between 5.5 and 7 months after ACL reconstruction with a Biodex(r isokinetic dynamometer (System 4 Pro with test protocol CON/CON at 60°/s and 300°/s with 5 and 15 repetitions, respectively. In the calculation of local muscle fatigue, the fatigue index was used, which is calculated by dividing the labor done in the first one-third of the repetitions by that done at the final one-third of the repetitions, and multiplying by 100 to express a unit in percentage (i.e., as a discrete quantitative variable. RESULTS: All subjects were male, with a mean age of 21.3 ± 4.4 years and mean BMI 23.4 ± 1.53 cm; left dominance was observed in 47% (n = 8 of athletes, and right dominance, in 53% (n = 9 of athletes; and the limb involved in the lesion was the dominant in 29% (n = 5 and the non-dominant in 71% (n = 12. Fatigue rates were 19.6% in the involved limb and 29.0% in the non-involved limb. CONCLUSION: The results allow us to conclude that there was no significant difference between the limbs involved and not in ACL injuries regarding local muscle fatigue. No association was observed between the dominant side and the limb involved in the ACL injury.
Shalaj, I; Tishukaj, F; Bachl, N; Tschan, H; Wessner, B; Csapo, R
The incidence and severity of football-related injuries has been found to differ strongly between professional leagues from different countries. The aims of this study were to record the incidence, type and severity of injuries in Kosovarian football players and investigate the relationship between injury incidence rates (IRs), players' age and playing positions. Players' age, anthropometric characteristics and playing positions, training and match exposure as well as injury occurrences were monitored in 11 teams (143 players) of Kosovo's top division during the 2013/14 season. The exact type, severity and duration of football-related injuries were documented following International Federation of Football Associations (FIFA) recommendations. A total of 272 injuries were observed, with traumatic injuries accounting for 71 %. The overall injury IR was 7.38 (CI: 7.14, 7.63) injuries per 1,000 exposure hours and ~11x lower during training as opposed to matches. Strains and ruptures of thigh muscles, ligamentous injuries of the knee as well as meniscus or other cartilage tears represented the most frequent differential diagnoses. While no statistical differences were found between players engaged in different playing positions, injury IR was found to be higher by 10-13 % in younger (IR = 7.63; CI: 7.39, 7.87) as compared to middle-aged (IR = 6.95; CI: 6.41, 7.54) and older players (IR = 6.76; CI: 5.71, 8.00). The total injury IR in elite football in Kosovo is slightly lower than the international average, which may be related to lesser match exposure. Typical injury patterns agree well with previously reported data. Our finding that injury IR was greater in younger players is related to a higher rate of traumatic injuries and may indicate a more aggressive and risky style of play in this age group.
Haan, M.; Koning, Ruud H.; Witteloostuijn, A. van
Recent decades have witnessed major changes in the market for European soccer. The most profound were the Bosman ruling, which lifted restrictions in the European labor market for soccer talent, and the introduction of the Champions' League, a high-profile international competition that generates
Haan, M.; Koning, Ruud H.; Witteloostuijn, A. van
Recent decades have witnessed major changes in the market for European soccer. The most profound were the Bosman ruling, which lifted restrictions in the European labor market for soccer talent, and the introduction of the Champions' League, a high-profile international competition that generates
Grégory Hallé Petiot
Full Text Available Abstract Aim The aim of this research is to identify the mechanisms that lead soccer players to make quality tactical decisions, and how these mechanisms evolve over time. Methods Ninety male youth players training in a professional club in Brazil were submitted to a soccer video test which consists in making tactical decisions when the image freezes. These participants were divided in five groups with 18 players in each of following age levels: Under-11, Under-13, Under-15, Under-17 and Under-20. The dominant statements of verbal reports were distributed in categories that reflect key mechanisms. The frequency of correct tactical answers was calculated for each statement types and Standard Residuals (e were calculated to verify the influence of the mechanisms on the quality of tactical decision for each age level. Results Results revealed that evaluation statement was related to accurate tactical decisions from Under-15 age level. Conclusion In conclusion, evaluation of perceived information makes better decision makers.
Vanderson Luis Moro
Full Text Available The aim of this study was to compare anaerobic capacity in professional soccer players of different competitive levels in their respective positions in the game, early in the preseason. The study group consisted of 44 male athletes belonging to two groups (A and B of different competitive levels. Group A was composed of 20 athletes participating in the Sagres League - Portuguese. Group B was composed of 24 athletes participating in the 2nd division Championship Gaucho - Brazil. For the assessment of anaerobic capacity it was applied the Running-based Anaerobic Sprint Test - RAST. For data analysis it was used the Student t test for independent samples and analysis of variance (ANOVA One Way supplemented with post hoc Tukey. Results showed that group A athletes performed better on the average power and worst values for the fatigue index. In the group A it was found statistical difference between attacks and other two positions (midfielder and side back for the fatigue index. It is concluded that there was significant differences in anaerobic capacity, measured at the start of the preseason, evaluated soccer players who work in competitions of different levels and positions play (group A.
Ferraz, Ricardo; Gonçalves, Bruno; Van Den Tillaar, Roland; Jiménez Sáiz, Sergio; Sampaio, Jaime; Marques, Mário C
The aim of this study was to identify the influence of prior knowledge of exercise duration on players' pacing patterns during soccer small-sided games. Twenty semi-professional male soccer players participated in this study. In the first game scenario, players were not informed how long they would be required to play the small-sided game and the activity was terminated after 20 min (Unknown Condition). In the second game scenario, players were told that they would play the small-sided game for 10 min, but immediately after completing the 10-min game, they were asked to complete another 10 min (Partially Condition). In the third game scenario, players were instructed that they would play the small-sided game for 20 min and then they completed the 20-min game (Known Condition). The results presented a tendency of higher values in all performance variables in the [0'-10'] min compared with the [10'-20'] min. As the players' previous knowledge about the tasks duration increased, the performance between two moments tended to be similar. Considering the entire 20-min game duration, the Partially Condition of the exercise was the most demanding condition. In conclusion, the knowledge of shorter durations of the exercise seems to lead to an increase of exercise duration demand, and longer exercise durations possibly tend to decrease differences between full knowledge and not knowing the exercise duration.
Williams, Craig A; Blackwell, Jamie
The purpose of the study was to determine the hydration status, fluid intake, and electrolyte losses of 21 male professional youth soccer players (age 17.1 ± 0.7 y) training in a cool environment. Pretraining and posttraining measurements of body mass, urine (freezing-point osmolality method), and sweat concentration (flame-emission spectroscopy) were collected. Fourteen players were found to be hypohydrated before training. The amount of fluid lost due to exercise equated to a 1.7% loss in body mass, which equated to a gross dehydration loss of 0.5%. Overall, the soccer players replaced 46% ± 88% of sweat loss during training, and only 4 remained hypohydrated after training. No significant correlations between sweat loss and sweat concentrations of Na+ (r = -.11, P = .67) or K+ (r = .14, P = .58) were found, but there was a significant correlation with Mg2+ (r = -.58, P hydration status that the players were able to rehydrate during the training sessions. However, given the numbers starting training in a hypohydrated state, adequate hydration status before training should be considered by youth players, coaches, and sports-science support staff.
Sanchis-Moysi, Joaquin; Idoate, Fernando; Izquierdo, Mikel; Calbet, Jose A. L.; Dorado, Cecilia
Purpose To determine the volume and degree of asymmetry of iliopsoas (IL) and gluteal muscles (GL) in tennis and soccer players. Methods IL and GL volumes were determined using magnetic resonance imaging (MRI) in male professional tennis (TP) and soccer players (SP), and in non-active control subjects (CG) (n = 8, 15 and 6, respectively). Results The dominant and non-dominant IL were hypertrophied in TP (24 and 36%, respectively, Psoccer players had similar volumes in both sides (P = 0.87). The degree of side-to-side asymmetry decreased linearly from the first lumbar disc to the pubic symphysis in TP (r = −0.97, PSoccer and CG had similar GL volumes in both sides (P = 0.11 and P = 0.19, for the dominant and contralateral GL, respectively). GL was asymmetrically hypertrophied in TP. The non-dominant GL volume was 20% greater in TP than in CG (Psoccer is associated to a symmetric hypertrophy of IL. Gluteal muscles are asymmetrically hypertrophied in TP, while SP display a similar size to that observed in controls. It remains to be determined whether the different patterns of IL and GL hypertrophy may influence the risk of injury. PMID:21829539
In this ethnographic research of a college-based soccer team at a large liberal college in Northeast America, I document the existence of more inclusive versions of masculinity that contrast conventional understandings of male teamsport athletes. Using participant observation and 21 in-depth interviews, I show that these men demonstrate metrosexual and inclusive behaviors and attitudes. The styles of masculinity these men enact are more relaxed, liberal, and inclusive; they are well styled, well groomed, gay friendly, and they are emotionally and physically close to other men. They are far removed from the traditional orthodox sporting masculinities of previous generations. Symbolizing their difference, their gendered expressions also extend to the wearing of pink soccer boots (cleats), without homophobic judgment from teammates. I discuss the wearing of pink cleats as a symbolic sociological moment, revealing the changing nature of masculinities among this group of college-based soccer players.
Ali, Ajmol; Williams, Clyde
The aim of this study was to investigate the effect of ingesting a carbohydrate-electrolyte solution, during the 90-min Loughborough Intermittent Shuttle Test, on soccer skill performance. Seventeen male soccer players ingested either a 6.4% carbohydrate-electrolyte solution or placebo solution equivalent to 8 ml . kg(-1) body mass before exercise and 3 ml . kg(-1) body mass after every 15 min of exercise, in a double-blind randomized cross-over design, with the trials separated by 7 days. The evening before the main trial, the participants performed glycogen-reducing exercise on a cycle ergometer (80 min at 70%[Vdot]O(2max)) and were then fed a low-carbohydrate meal. After a 12-h overnight fast, they performed The Loughborough Soccer Passing Test before and after every 15 min of exercise. Analysis of the combined skill test data showed a significant time effect (P = 0.001) with differences between 0-45 and 75-90 min (P exercise in the carbohydrate-electrolyte trial, whereas in the placebo trial the decrease was 14% (P = 0.07). In conclusion, skill performance during the simulated soccer activity appeared to deteriorate in the last 15-30 min of exercise. However, providing 52 g . h(-1) carbohydrate during exercise showed a tendency to better maintain soccer skill performance than a taste-matched placebo.
Full Text Available The aim of this study was to evaluate the normalized response speed (Vrn of the knee musculature (flexor and extensor in high competitive level volleyball players using tensiomyography (TMG and to analyze the muscular response of the vastus medialis (VM, rectus femoris (RF, vastus lateralis (VL, and biceps femoris (BF in accordance with the specific position they play in their teams. One hundred and sixty-six players (83 women and 83 men were evaluated. They belonged to eight teams in the Spanish women’s superleague and eight in the Spanish men’s superleague. The use of Vrn allows avoiding possible sample imbalances due to anatomical and functional differences and demands. We found differences between Vrn in each of the muscles responsible for extension (VM, RF, and VL and flexion (BF regardless of the sex. Normalized response speed differences seem to be larger in setters, liberos and outside players compared to middle blockers and larger in males when compared to females. These results of Vrn might respond to the differences in the physical and technical demands of each specific position, showing an improved balance response of the knee extensor and flexor musculature in male professional volleyball players.
Rodríguez-Ruiz, D.; Diez-Vega, I.; Rodríguez-Matoso, D.; Fernandez-del-Valle, M.; Sagastume, R.; Molina, J. J.
The aim of this study was to evaluate the normalized response speed (Vrn) of the knee musculature (flexor and extensor) in high competitive level volleyball players using tensiomyography (TMG) and to analyze the muscular response of the vastus medialis (VM), rectus femoris (RF), vastus lateralis (VL), and biceps femoris (BF) in accordance with the specific position they play in their teams. One hundred and sixty-six players (83 women and 83 men) were evaluated. They belonged to eight teams in the Spanish women's superleague and eight in the Spanish men's superleague. The use of Vrn allows avoiding possible sample imbalances due to anatomical and functional differences and demands. We found differences between Vrn in each of the muscles responsible for extension (VM, RF, and VL) and flexion (BF) regardless of the sex. Normalized response speed differences seem to be larger in setters, liberos and outside players compared to middle blockers and larger in males when compared to females. These results of Vrn might respond to the differences in the physical and technical demands of each specific position, showing an improved balance response of the knee extensor and flexor musculature in male professional volleyball players. PMID:25003109
Rodríguez-Ruiz, D; Diez-Vega, I; Rodríguez-Matoso, D; Fernandez-del-Valle, M; Sagastume, R; Molina, J J
The aim of this study was to evaluate the normalized response speed (Vrn) of the knee musculature (flexor and extensor) in high competitive level volleyball players using tensiomyography (TMG) and to analyze the muscular response of the vastus medialis (VM), rectus femoris (RF), vastus lateralis (VL), and biceps femoris (BF) in accordance with the specific position they play in their teams. One hundred and sixty-six players (83 women and 83 men) were evaluated. They belonged to eight teams in the Spanish women's superleague and eight in the Spanish men's superleague. The use of Vrn allows avoiding possible sample imbalances due to anatomical and functional differences and demands. We found differences between Vrn in each of the muscles responsible for extension (VM, RF, and VL) and flexion (BF) regardless of the sex. Normalized response speed differences seem to be larger in setters, liberos and outside players compared to middle blockers and larger in males when compared to females. These results of Vrn might respond to the differences in the physical and technical demands of each specific position, showing an improved balance response of the knee extensor and flexor musculature in male professional volleyball players.
González-Víllora, Sixto; Pastor-Vicedo, Juan C; Cordente, David
Relative Age Effect (RAE) is the breakdown by both age grouping and dates of birth of athletes. In the past 20 years the existence of this effect has been shown with higher or smaller impact in multiple sports, including soccer. The purpose of this study was to identify the existence of RAE in European soccer players. The sample included 841 elite soccer players who were participants in the UEFA European Soccer Championship in different categories. The professional category (n = 368), U-19 (n = 144) and U-17 (n = 145) were in 2012, and U-21 was in 2011 (n = 184). The Kolmogorov-Smirnov test and the Levene test recommended the use of nonparametric statistics. The results obtained by the square test ( the Kruskal-Wallis test and Cohen's effect sizes revealed the existence of RAE (χ(2) = 17.829, p tested. RAE was not evident in the professional teams analysed, however it was present in the three lower categories analysed (youth categories), with its influence being greater on younger age categories (U-17).
Davis, J A; Brewer, J
Women's soccer is in its infancy as a sport and research into its physiological demands and the physical characteristics of players is somewhat limited. There is now an increasing demand for scientific investigation of the female game and of the players, match analysis and role variations requiring particular attention. Current research suggests that the demands of the game for women are similar to those placed on male players. Women are reported to cover a similar distance (mean 8471m) to their male counterparts during a game and much the same proportions of the game appear to be devoted to exercise of varying intensities. Furthermore, female and male players appear to tax the aerobic and anaerobic energy systems to a similar level. The physical and physiological characteristics of female soccer players are comparable with those of other female games players and are more favourable than average for the population. Mean body fat percentages of between 19.7 and 22.0% and VO2max values of between 47.1 and 57.6 ml/kg/min have been reported for elite female players, while faster than average sprint times are also characteristic of them.
Distribuição de subgrupos com base nas respostas fisiológicas em jogadores profissionais de futebol pela técnica K Means Cluster Subgroup distribution based on physiological responses in professional soccer players by K-means cluster technique
Luiz Fernando Novack
improved in all athletes collectively. CONCLUSION: The results make us conclude that group distribution by K Means Clustering technique can be performed using physiological responses of athletes in an attempt to optimize training for professional soccer players with focus on the common main training needs regardless of their tactical function played on the field.
Alessandra Favano; Paulo Roberto Santos-Silva; Eduardo Yoshio Nakano; André Pedrinelli; Arnaldo José Hernandez; Julia Maria D´Andrea Greve
OBJECTIVE: To investigate whether supplementation of carbohydrate together with peptide glutamine would increase exercise tolerance in soccer players. METHODS: Nine male soccer players (mean age: 18.4 ± 1.1 years; body mass: 69.2 ± 4.6 kg; height: 175.5 ± 7.3 cm; and maximum oxygen consumption of 57.7 ± 4.8 ml.kg-1.min-1) were evaluated. All of them underwent a cardiopulmonary exercise test and followed a protocol that simulated the movements of a soccer game in order to evaluate their tolera...
Goedecke, Julia H.; White, Nicholas J.; Waheed Chicktay; Hafsa Mahomed; Justin Durandt; Lambert, Michael I.
Aim: This study investigated how performance was affected after soccer players, in a postprandial state, ingested a 7% carbohydrate (CHO) solution compared to a placebo (0% CHO) during a simulated soccer match. Methods: Using a double-blind placebo-controlled design, 22 trained male league soccer players (age: 24 ± 7 years, wt: 73.4 ± 12.0 kg, VO2max: 51.8 ± 4.3 mL O2/kg/min) completed two trials, separated by 7 days, during which they ingested, in random order, 700 mL of either a 7% CHO or ...
Marcelo de Oliveira Matta; António José Barata Figueiredo; Emerson Silami Garcia; André Felipe Teixeira Seabra
DOI: http://dx.doi.org/10.5007/1980-0037.2014v16n3p277 The objectives of this study were to describe and compare the anthropometric profile, physical fitness and soccer-specific skills between under-15 and under-17 Brazilian soccer players, as well as to evaluate possible differences in these variables according to biological maturation in the age categories. The sample consisted of 245 male soccer players (under-15: n=161; under-17: n=84). Anthropometric measures included weight, hei...
Simim, Mário A; Bradley, Paul S; da Silva, Bruno V; Mendes, Edmar L; de Mello, Marco T; Marocolo, Moacir; da Mota, Gustavo R
This study quantified the degree of game-induced muscular fatigue in amputee soccer players. Thirty-three male amputee soccer players performed muscular tests (Push Up Test [PUT], Countermovement Jump Test [CMJ] and medicine-ball throw [MBT]) before and after a competitive match. Five players served as a control group. The rating of perceived exertion was recorded after each battery. Control group demonstrated no differences between the two testing batteries (P>0.05, effect size [ES]: 0.1-0.4). However, match group illustrated markedly lower performances for PUT (-17%, Pamputee soccer matches causes impairments in muscular performance and this could be different to able-bodied players.
Hidalgo y Teran Elizondo, Roberto; Martín Bermudo, Francisco Manuel; Peñaloza Mendez, Ricardo; Berná Amorós, Genoveva; Lara Padilla, Eleazar; Berral de la Rosa, Francisco José
nutritional intake and status of soccer players has attracted not much research attention. Many soccer players follow an inadequate nutritional intake and have a poor nutritional status. This is relevant in youngsters soccer players, in order to improve performance and promote healthy dietary practices. analyze anthropometric characterizes, evaluate nutritional intake and status, dietary habits and pre- and post-exercise meals in elite teenagers soccer players. seventy-two young male soccer players (15-20 years) from four junior teams of a soccer Club from the Mexican National Soccer League were measured for height, seat height, weight, 6 skinfolds, 6 diameters and 7 circumferences, height-for-age and BMI-for-age values. Skin, adipose, muscle, bone and residual tissue masses were calculated with the Ross and Kerr equation. Resting energy expenditure and intake was also measured. Daily dietary intake was self-recorded for 4 consecutive days (excluding the match day) using a digital food-weighing scale and a food record questionnaire. Dietary analysis was performed using the NutriBase 7 Clinical software. Several biochemical values were determined. One-way analysis of variance (ANOVA) and post hoc testing was performed using t-tests with a Bonferroni correction. all soccer players were within the normal range values for anthropometric parameters studies, when compared with other adolescent elite soccer teams. Values of plasma glucose, urea, creatinine, uric acid, lipid profile and total proteins were within normal range for young adult population, although albumin levels were high. Moreover, 14% and 20% of soccer players presented hyperuricemia and elevated total cholesterol levels respectively. Energy expenditure and intake were within normal range for all teenager elite soccer players. However, two teams shower significant lower intakes than demands. All macronutrient intakes were within recommendations, except protein that was higher. Micronutrient intake exceeded
Rodrigues, Ana Carolina; Lasmar, Rodrigo Pace; Caramelli, Paulo
Soccer is the most popular sport in the world, with more than 265 million players worldwide, including professional and amateur ones. Soccer is unique in comparison to other sports, as it is the only sport in which participants purposely use their head to hit the ball. Heading is considered as an offensive or defensive move whereby the player’s unprotected head is used to deliberately impact the ball and direct it during play. A soccer player can be subjected to an average of 6–12 incidents of heading the ball per competitive game, where the ball reaches high velocities. Moreover, in practice sessions, heading training, which involves heading the ball repeatedly at low velocities, is common. Although the scientific community, as well as the media, has focused on the effects of concussions in contact sports, the role of subconcussive impacts, as it can occur during heading, has recently gained attention, considering that it may represent an additional mechanism of cumulative brain injury. The purpose of this study is to review the existing literature regarding the effects of soccer heading on brain structure and function. Only in the last years, some investigations have addressed the impact of heading on brain structure, by using neuroimaging techniques. Similarly, there have been some recent studies investigating biochemical markers of brain injury in soccer players. There is evidence of association between heading and abnormal brain structure, but the data are still preliminary. Also, some studies have suggested that subconcussive head impacts, as heading, could cause cognitive impairment, whereas others have not corroborated this finding. Questions persist as to whether or not heading is deleterious to cognitive functioning. Further studies, especially with longitudinal designs, are needed to clarify the clinical significance of heading as a cause of brain injury and to identify risk factors. Such investigations might contribute to the establishment of safety
Leskošek, Bojan; Vodičar, Janez; Topič, Mojca Doupona
Abstract The purpose of this study was to identify factors that constituted the cultural capital among soccer players. We assumed that in the increasingly globalized world of professional soccer, a player’s success would often depend on migrating and adjusting to life in other countries. Willingness to migrate and successful adjustment are tied to player’s previous attitudes and/or behaviours (habitus), significant support from others, including family members, and previous experiences and success in sports and education. Our hypothesised model of the cultural capital was based on the Pierre Bourdieu’s theoretical framework. It consisted of 26 variables related to three sets of factors: soccer experiences, a family context and support, and educational achievements of the players and their parents. The model was tested using a sample of 79 current soccer coaches who also had been players at the elite level. A factor analysis was used to empirically verify the content of the hypothetical model of the soccer players’ cultural capital. Nine latent factors were extracted and together, they accounted for 55.01% of the total model variance. Individual factors obtained showed a sufficient level of substantial connection. The Cronbach’s alpha value of 0.77 confirmed the internal consistency of the operationalised variables in the hypothetical model. In addition, the impact of these aforementioned life dimensions on the migration of soccer players was studied. The results of the binary logistic regression analysis showed that the first factor of the hypothetical model (F1) had 2.2 times and the second factor (F8) had 3.9 times higher odds for migration abroad. Sociocultural findings using this new assessment approach could help create better “success conditions” in the talent development of young players. PMID:28031770
Križaj, Jožef; Leskošek, Bojan; Vodičar, Janez; Topič, Mojca Doupona
The purpose of this study was to identify factors that constituted the cultural capital among soccer players. We assumed that in the increasingly globalized world of professional soccer, a player's success would often depend on migrating and adjusting to life in other countries. Willingness to migrate and successful adjustment are tied to player's previous attitudes and/or behaviours (habitus), significant support from others, including family members, and previous experiences and success in sports and education. Our hypothesised model of the cultural capital was based on the Pierre Bourdieu's theoretical framework. It consisted of 26 variables related to three sets of factors: soccer experiences, a family context and support, and educational achievements of the players and their parents. The model was tested using a sample of 79 current soccer coaches who also had been players at the elite level. A factor analysis was used to empirically verify the content of the hypothetical model of the soccer players' cultural capital. Nine latent factors were extracted and together, they accounted for 55.01% of the total model variance. Individual factors obtained showed a sufficient level of substantial connection. The Cronbach's alpha value of 0.77 confirmed the internal consistency of the operationalised variables in the hypothetical model. In addition, the impact of these aforementioned life dimensions on the migration of soccer players was studied. The results of the binary logistic regression analysis showed that the first factor of the hypothetical model (F1) had 2.2 times and the second factor (F8) had 3.9 times higher odds for migration abroad. Sociocultural findings using this new assessment approach could help create better "success conditions" in the talent development of young players.
Full Text Available The purpose of this study was to identify factors that constituted the cultural capital among soccer players. We assumed that in the increasingly globalized world of professional soccer, a player’s success would often depend on migrating and adjusting to life in other countries. Willingness to migrate and successful adjustment are tied to player’s previous attitudes and/or behaviours (habitus, significant support from others, including family members, and previous experiences and success in sports and education. Our hypothesised model of the cultural capital was based on the Pierre Bourdieu’s theoretical framework. It consisted of 26 variables related to three sets of factors: soccer experiences, a family context and support, and educational achievements of the players and their parents. The model was tested using a sample of 79 current soccer coaches who also had been players at the elite level. A factor analysis was used to empirically verify the content of the hypothetical model of the soccer players’ cultural capital. Nine latent factors were extracted and together, they accounted for 55.01% of the total model variance. Individual factors obtained showed a sufficient level of substantial connection. The Cronbach’s alpha value of 0.77 confirmed the internal consistency of the operationalised variables in the hypothetical model. In addition, the impact of these aforementioned life dimensions on the migration of soccer players was studied. The results of the binary logistic regression analysis showed that the first factor of the hypothetical model (F1 had 2.2 times and the second factor (F8 had 3.9 times higher odds for migration abroad. Sociocultural findings using this new assessment approach could help create better “success conditions” in the talent development of young players.
Borges, G M; Vaz, M A; De La Rocha Freitas, C; Rassier, D E
The purpose of this study was to describe the torque-velocity (T-V) relationship during concentric and eccentric contractions of the lower limb muscles in professional soccer players. Soccer players (n=10) that were training systematically for at least 5 years were compared with moderately active individuals (n=13), that were not engaged in any systematic physical activity program in the last 5 years. Peak torque, and angle-specific torque at knee angles of 0.52 rad and 1.04 rad were evaluated during maximal concentric and eccentric contractions at 0.52 rad x sec(-1), 1.04 rad x sec(-1), 1.57 rad x sec(-1), 2.09 rad x sec(-1), 3.14 rad x sec(-1), 4.19 rad x sec(-1) and 5.23 rad x sec(-1) angular velocities. During concentric contractions, inverse hyperbolic relationships were fitted for the two groups [T = T(max) + (a x b)/(b + V)], with values for a and b of 1.4 and 347.6 for the control group, respectively, and 1.9 and 605.4 for the soccer players, respectively. When torque was measured at 0.52 rad, the torque-velocity relationship presented a plateau at low velocities in the two groups investigated. When torque was measured at 1.04 rad, the torque-velocity relationship presented a plateau at low velocities in the control group, in which force did not increase significantly as velocity was decreased. The plateau was not observed in soccer players. Peak torque and torque measured at 1.04 rad were higher in the soccer players than in the control group in all velocities investigated. However, the biggest difference was found in lower velocities of contraction. Soccer players produced a higher muscle torque in the lower limb than moderately active individuals, and this difference was bigger when the velocities were low.
Ana Carolina Oliveira Rodrigues
Full Text Available Soccer is the most popular sport in the world, with more than 265 million players worldwide, including professional and amateur ones. Soccer is unique in comparison to other sports, as it is the only sport in which participants purposely use their head to hit the ball. Heading is considered an offensive or defensive move whereby the player’s unprotected head is used to deliberately impact the ball and direct it during play. A soccer player can be subjected to an average of six to twelve incidents of heading the ball per competitive game, where the ball reaches high velocities. Moreover, in practice sessions, heading training, which involves heading the ball repeatedly at low velocities, is common. Although the scientific community, as well as the media, has focused on the effects of concussions in contact sports, the role of subconcussive impacts, as it can occur during heading, has recently gained attention, considering that it may represent an additional mechanism of cumulative brain injury. The purpose of this study is to review the existing literature regarding the effects of soccer heading on brain structure and function. Only in the last years some investigations have addressed the impact of heading on brain structure, by using neuroimaging techniques. Similarly, there have been some recent studies investigating biochemical markers of brain injury in soccer players. There is evidence of association between heading and abnormal brain structure, but the data are still preliminary. Also, some studies have suggested that subconcussive head impacts, as heading, could cause cognitive impairment, whereas others have not corroborated this finding. Questions persist as to whether or not heading is deleterious to cognitive functioning. Further studies, especially with longitudinal designs, are needed to clarify the clinical significance of heading as a cause of brain injury and to identify risk factors. Such investigations might contribute to the
B.C. Huijgen; M Coelho-e-Silva; MT Elferink-Gemser; C Visscher; Koen A.P.M. Lemmink
Abstract: Talent development programmes for professional soccer clubs aim to guide players towards professional level performance. We identify whether the intermittent endurance capacity of these players may have changed over time. Since the 2000/2001 competition season, the intermittent endurance
Elferink-Gemser, Marije T.; Huijgen, Barbara C. H.; Coelho-E-Silva, Manuel; Lemmink, Koen A. P. M.; Visscher, Chris
Talent development programmes for professional soccer clubs aim to guide players towards professional level performance. We identify whether the intermittent endurance capacity of these players may have changed over time. Since the 2000/2001 competition season, the intermittent endurance capacity of
La influencia de la densidad competitiva en el resultado de los equipos en el fútbol de alto nivel. (The influence of a congested football calendar on the results obtained by teams in professional soccer.
Joaquín Lago Ballesteros
Full Text Available Resumen Existe una considerable variación en el número de partidos disputados por los equipos de fútbol durante una temporada. Los mejores equipos juegan varios partidos a la semana tanto en las competiciones domesticas como en la Liga de Campeones. Se ha especulado que un período cargado de partidos puede limitar el rendimiento de los conjuntos. En este trabajo se estudia el efecto que tiene para un equipo disputar un partido de la Liga de Campeones sobre el resultado alcanzado en el encuentro de la Liga Española en el fin de semana anterior. La muestra consiste en 374 partidos de la Liga Española jugados por los equipos que se encontraban simultáneamente disputando la Liga de Campeones entre las temporadas 2003-2004 y 2006- 2007. Los resultados alcanzados mediante un modelo logit multinomial permiten demostrar que disputar un partido de la Liga de Campeones no reduce la probabilidad de ganar en el partido de la Liga Española. Además se ha verificado que la probabilidad de ganar en el partido del fin de semana de la Liga Española es mayor cuando el partido de la Liga de Campeones a disputar pertenece a la fase de liguilla respecto a si se corresponde con el formato de eliminación directa.Palabras clave: fútbol; liga española; liga de campeones; logit multinomial; densidad competitive. Abstract There is a considerable variation in the number of matches played per season by clubs in the Spanish Soccer. The successful top clubs play several matches a week in domestic leagues as well as in the UEFA Champions League. It has been speculated that a period full of matches can lead to player fatigue which may result in underperformance. Using data from 374 matches of the Spanish Soccer League played from the 2003-04 to the 2006-07 seasons and according to the estimation based on logit multinomial this study shows that Spanish Champions League teams did not perform below their normal standard at the weekend when they played a Champions
Krustrup, Peter; Nielsen, Jens Jung; Krustrup, Birgitte
To examine the effects of regular participation in recreational soccer on health profile, 38 healthy untrained Danish males aged 20-43 years were randomised into a soccer group (SO; n=14), a running group (RU; n=13) and a control group (CO; n=11). Training was performed for one hour two-three tim...... men, and in some aspects it is superior to frequent moderate intensity running....
Linthorne, NP; Everett, DA
We investigated the release angle that maximises the distance attained in a long soccer throw-in. One male soccer player performed maximum-effort throws using release angles of between 10 and 60º, and the throws were analysed using two-dimensional videography. The player’s optimum release angle was calculated by substituting mathematical expressions for the measured relationships between release speed, release height and release angle into the equations for the flight of a spherical project...
Junge, A; Cheung, K; Edwards, T; Dvorak, J
Objectives: In reviewing the literature on sports injuries, few studies could be found in which exposure related incidences of injury in different types of sport were compared. These studies indicated that ice hockey, handball, basketball, soccer, and rugby are popular team sports with a relatively high risk of injury. The aim of the study was to compare the characteristics and incidence of injuries in male youth amateur soccer and rugby players. Methods: This prospective cohort study comprised an initial baseline examination to ascertain the characteristics of the players and their level of performance, and a one season observation period during which a physician visited the team weekly and documented all occurring injuries. Twelve soccer