McKay, D H
In brief: Lower extremity injuries are common in downhill skiing. Fifty-three percent of the skiing injuries in one study, and 81% in another, were below the knee. Twelve case reports are presented and their treatment is discussed. The author suggests that skiers undertake a physical fitness program to increase stamina and elasticity of muscles and ligaments.
Meyers, Michael C; Laurent, C Matthew; Higgins, Robert W; Skelly, William A
Downhill skiing is considered to be an enjoyable activity for children and adolescents, but it is not without its risks and injuries. Injury rates now range between 3.9 and 9.1 injuries per 1000 skier days, and there has been a well documented increase in the number of trauma cases and fatalities associated with this sport. Head and neck injuries are considered the primary cause of fatal injuries and constitute 11-20% of total injuries among children and adolescents. Cranial trauma is responsible for up to 54% of total hospital injuries and 67% of all fatalities, whereas thoracoabdominal and spine injuries comprise 4-10% of fatalities. Furthermore, there has been an increase in the proportion of upper extremity trauma with acromioclavicular dislocations, and clavicle and humeral fractures accounting for the majority (22-79%) of the injuries. However, the most common and potentially serious injuries in children and adolescents are those to the lower extremity, with knee sprains and anterior cruciate ligament tears accounting for up to 47.7% of total injuries. Knee sprains and grade III ligament trauma associated with lower leg fractures account for 39-77% of ski injuries in this young population. Approximately 15% of downhill skiing injuries among children and adolescents are caused by musculoskeletal immaturity. Other factors include excessive fatigue, age, level of experience, and inappropriate or improperly adjusted equipment. Collisions and falls constitute a significant portion (up to 76%) of trauma, and are commonly associated with excessive speed, adverse slope conditions, overconfidence leading to carelessness, and behavioural patterns within and among gender. The type and severity of injuries are typically functions of biomechanical efficiency, skiing velocity or slope conditions; however, a multiplicative array of intrinsic and extrinsic factors may simultaneously be involved. Despite extensive efforts to provide a comprehensive picture of the aetiology of
Wu, Qianhong; Igci, Yesim; Andreopoulos, Yiannis; Weinbaum, Sheldon
This study is conducted to develop a simplified mathematical model to describe the lift mechanics of downhill skiing and snowboarding, where the lift contributions due to both the transiently trapped air and the compressed solid phase (snow crystals) are determined. To our knowledge, this is the first time that anyone has attempted to realistically estimate the relative contribution of the transiently trapped air to the total lift in skiing and snowboarding. The model uses Shimizu's empirical relation to predict the local variation in Darcy permeability due to the compression of the solid phase. The forces and moments on the skier or snowboarder are used to predict the angle of attack of the planing surface, the penetration depth at the leading edge, and the shift in the center of pressure for two typical snow types, fresh and wind-packed snow. We present numerical solutions for snowboarding and asymptotic analytic solutions for skiing for the case where there are no edging or turning maneuvers. The force and moment balance are then used to develop a theory for control and stability in response to changes in the center of mass as the individual shifts his/her weight. Our model predicts that for fine-grained, windpacked snow that when the velocity (U) of the snowboarder or skier is 20 m.s, approximately 50% of the total lift force is generated by the trapped air for snowboarding and 40% for skiing. For highly permeable fresh powder snow, the lift contribution from the pore air pressure drops substantially. This paper develops a new theoretical framework for analyzing the lift mechanics and stability of skis and snowboards that could have important applications in future ski and snowboard design.
Downhill skiing is associated with recreation, youth, speed, aerials and crowded courses which carry increased risk of injuries. The aim of this study was to evaluate downhill sport injuries in a Swedish ski resort. Material and methodsIn a case-control study ongoing 1989/90–2006/07, 3,696 injured skiers were registered. After informed consent the injured were assessed by a physician and asked to answer a questionnaire concerning skier, skiing and injury. ResultsAfter three years 481 injured ...
Tesch, P; Larsson, L; Eriksson, A; Karlsson, J
Skilled and unskilled skiers were studied during downhill skiing. Muscle glycogen and muscle lactate concentrations in the vastus lateralis muscle were determined following different skiing conditions. Heavy glycogen utilization was found in the groups studied during a day of skiing. The skilled and unskilled skiers differed with respect to selective glycogen depletion pattern and the skilled subjects demonstrated greater depletion of slow twitch fibers than the unskilled subjects. Lactate concentrations ranged from approximately 5-26 mmoles x kg-1 wet muscle after approximately one minute of maximal skiing. This wide range was not found to be related to the level of skiing proficiency. However, skiing with varyingly angled boots, resulting in different knee angles, did affect lactate concentration. Lactate concentration was positively correlated to individual muscle fiber composition expressed as a percent of fast twitch fibers. The results suggest more pronounced involvement of aerobic energy metabolism in skilled skiers than in unskilled skiers.
Buck, P G; Sophocles, A M; Beckenbauch, R D
Skiing is an exciting sport with a significant potential /or serious injury. This potential for injury can be minimized but never entirely eliminated by modern safety equipment.Upper extremity injuries have become relatively more common as the incidence of lower extremity injuries has decreased. Ankle and foot injuries have become infrequent since the advent of the rigid plastic boot, while the incidence of knee injuries has remained essentially constant.Three major mechanisms of injury to the lower extremity include external rotation and abduction, forward fall, and internal rotation. Each mechanism can produce a distinctive set of injured structures.The "skier at risk" is characterized by a lower level of ability, lighter weight, and extremes of age. Injuries can be minimized by purchasing good quality equipment and maintaining it properly; discarding obsolete equipment; using ski brakes, antifriction devices and pistol grip poles; using multirelease bindings for beginners or intermediates; good physical conditioning; taking ski lessons and coupling this with skiing experience; and skiing in control and using common sense on the slopes.Areas which need the most improvement in equipment design include multi-release bindings suitable for all skiers and children's boots. Copyright 2013, SLACK Incorporated.
Gilgien, Matthias; Spörri, Jörg; Kröll, Josef; Müller, Erich
Injuries in downhill (DH) are often related to high speed and, therefore, to high energy and forces which are involved in injury situations. Yet to date, no study has investigated the effect of ski geometry and standing height on kinetic energy (EKIN) in DH. This knowledge would be essential to define appropriate equipment rules that have the potential to protect the athletes' health. During a field experiment on an official World Cup DH course, 2 recently retired world class skiers skied on 5 different pairs of skis varying in width, length and standing height. Course characteristics, terrain and the skiers' centre of mass position were captured by a differential Global Navigational Satellite System-based methodology. EKIN, speed, ski-snow friction force (FF), ground reaction force (FGRF) and ski-snow friction coefficient (CoeffF) were calculated and analysed in dependency of the used skis. In the steep terrain, longer skis with reduced width and standing height significantly decreased average EKIN by ∼ 3%. Locally, even larger reductions of EKIN were observed (up to 7%). These local decreases in EKIN were mainly explainable by higher FF. Moreover, CoeffF differences seem of greater importance for explaining local FF differences than the differences in FGRF. Knowing that increased speed and EKIN likely lead to increased forces in fall/crash situations, the observed equipment-induced reduction in EKIN can be considered a reasonable measure to improve athlete safety, even though the achieved preventative gains are rather small and limited to steep terrain. 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/
Tyrol (Austria) is one of the regions which pioneered skiing. Skiing is considered as a national sport and is deeply rooted within the school system. Thus most pupils partake in skiing courses in this period. It is clear that such a large group of pupils also leads to a significant number of skiing injuries. Preventive issues may be derived from an analysis of the pattern and circumstances of skiing injuries. During a period of ten years (2000 - 2009) 1522 school sports injuries have been reported to the health insurance agency (Allgemeine Unfallversicherungsanstalt) from all secondary schools in Tyrol. The major disciplines were ski (48 %, n = 734) ice skateing (23 %, n = 349) and snowboard injuries (21 %, n = 315), followed by tobogganing (6 %, n = 91), cross-country skiing (1 %, n = 17) and other wintersports (1 %, n = 16). Fractures (31 %) dominated in skiing, followed by contusions (23 %), and sprains (22 %). In the analysis of the distribution of injuries during alpine skiing accidents, lower extremity injuries (39 %) dominated followed by upper extremity injuries (34 %). Head and spine injuries (13 %) were rare. Analysing the circumstances of the injuries, most injuries during skiing occurred without person to person collision (82 %), 81 % either shortly before lunch-break or in the afternoon. Skiing injuries account for a significant proportion of all school sport-related injuries in Tyrol. Lower extremity injuries account for the vast majority of all injuries. Overestimation and overtiredness may be responsible for skiing sport injuries. Preventive measures such as a fitness training (e. g., skiing exercises) prior to skiing courses, appropriate breaks and proper protective gear (i. e., helmet and spine protector) may reduce the injury rate in skiing school sport. © Georg Thieme Verlag KG Stuttgart · New York.
Gilgien, Matthias; Spörri, Jörg; Kröll, Josef; Müller, Erich
Background Injuries in downhill (DH) are often related to high speed and, therefore, to high energy and forces which are involved in injury situations. Yet to date, no study has investigated the effect of ski geometry and standing height on kinetic energy (EKIN) in DH. This knowledge would be essential to define appropriate equipment rules that have the potential to protect the athletes’ health. Methods During a field experiment on an official World Cup DH course, 2 recently retired world class skiers skied on 5 different pairs of skis varying in width, length and standing height. Course characteristics, terrain and the skiers’ centre of mass position were captured by a differential Global Navigational Satellite System-based methodology. EKIN, speed, ski–snow friction force (FF), ground reaction force (FGRF) and ski–snow friction coefficient (CoeffF) were calculated and analysed in dependency of the used skis. Results In the steep terrain, longer skis with reduced width and standing height significantly decreased average EKIN by ∼3%. Locally, even larger reductions of EKIN were observed (up to 7%). These local decreases in EKIN were mainly explainable by higher FF. Moreover, CoeffF differences seem of greater importance for explaining local FF differences than the differences in FGRF. Conclusions Knowing that increased speed and EKIN likely lead to increased forces in fall/crash situations, the observed equipment-induced reduction in EKIN can be considered a reasonable measure to improve athlete safety, even though the achieved preventative gains are rather small and limited to steep terrain. PMID:26702013
Stunt skiing is popular. It includes three disciplines: ski ballet, "hot dog" or "rough track" skiing and jumping. An extensive series of investigations showed that for well-trained professionals with suitable equipment and good outdoor conditions, the danger of injury is only slightly higher compared with normal skiing. Practising ballet figures considerably improves the stability of the good all-round skier.
Brookes, Andrew; Holmes, Peter
Supervised practice is a common feature of many snow sports excursions to downhill ski resorts by school or youth groups, often in combination with lessons from a ski school. What is the role of supervision in preventing mishaps, injury, or fatalities? This article presents results of a search of published snow sports safety research for evidence…
Stevo Popović; Blažo Jabučanin
The object of this project is marketing in modern sport procedure. The main focus will be directional to skiing and specific marketing in the area where it participated. The questions of sport marketing will be tested at Ski club “Mogren” from Budva. The main goal refers the requirement that sport in modern world should be presented as less simpler, cheaper and more attractive way. During last 30 years, sports, including the skiing, alike one of the Olympic sports, became much more active in ...
Charles R. Goeldner; Stacy Standley
A brief historical overview of skiing is presented, followed by a review of factors such as energy, population trends, income, sex, occupation and attitudes which affect the future of skiing. A. C. Neilson's Sports Participation Surveys show that skiing is the second fastest growing sport in the country. Skiing Magazine's study indicates there are...
Full Text Available Is certain the most rational method of the speed-up teaching of students of the first course of discipline «Ski sport». Positions are taken into account to credit-module departmental teaching. The individual differentiated technology of the accelerated training to ways of movement on a ski is proved. Technology includes three methods of teaching. Application of methods is varied depending on sporting specialization of students and development of their physical qualities. The rational parity of employment on training to technics of classical and skating styles of movement on a ski is determined.
Full Text Available The object of this project is marketing in modern sport procedure. The main focus will be directional to skiing and specific marketing in the area where it participated. The questions of sport marketing will be tested at Ski club “Mogren” from Budva. The main goal refers the requirement that sport in modern world should be presented as less simpler, cheaper and more attractive way. During last 30 years, sports, including the skiing, alike one of the Olympic sports, became much more active in the filed of selling the irproducts. The main tasks of this project are presenting and arranging the concept of marketing, strategic marketing, specific marketing in sport, marketing and sponsorship and importance of marketing in the modern sport at example of skiing. During the making of this project the authors used descriptive method with consulting of competent literature. The previous author’s experience in this field was so useful. More over, the authors used the analytic method and parallel method which is the most productive if you make some inferences about some appearance.
Skiing is a risky sport for many, even for children and beginners. When the ski-group is escorted by doctors who are able to provide advanced life support on the scene and are trained either in the field of emergency medicine or in travel medicine, a good possibility is given for the prevention of ski-accidents and for decreasing the number of travel related illnesses. This fact has led to the basic idea of training ski-camp doctors in Hungary. There is no similar initiative in the Hungarian literature. Therefore the article tries to summarise the medical knowledge and requirements of a ski-camp doctor, and analyses the prevention tasks of the doctor as well. The camp doctor must be well informed and highly trained in the field of emergency and travel medicine. The main tasks are: pre-travel advice, treatment of the common (travel-related) diseases, providing basic and advanced life-support on the scene, and to organise the hospitalisation and repatriation of patient, in cooperation with the hospital and insurance doctor. Moreover, the prevention should start before departure: the estimation of the physical and health condition of the skiers, a continuous care of the chronic people, and supervision of the place (hygienic circumstances, rescue forces available, the condition of the ski slopes, etc.) are vital--as for the primary prevention. The secondary level of the prevention is the treatment of the injured/sick persons, and assistance in the medical evacuation. During the training, not only postgraduate medical, mountain and alpine medicine lessons have been provided, but basic legal and insurance information as well. Moreover, the doctors received ski-course from professional ski-trainers in order to improve their ski-technique and skills on different slopes and off-piste places. In the future the local mountain rescue and air-rescue forces have to be involved in postgraduate training. Hopefully different travel-insurance companies and travel offices will use
Baker, Joseph; Janning, Christina; Wong, Harmonie; Cobley, Stephen; Schorer, Jörg
In many sports, policy-makers and administrators employ annual cohorts to reduce differences between athletes during childhood and youth. Although well-intended, unintended relative age effects (RAEs) usually occur. RAEs refer to the specific selection, participation and attainment disadvantages associated with participants' birthdates relative to an arbitrary 'cutoff' date used to group participants within annual age groups. To date, we have little understanding of RAEs in individual sports. In this article, Study 1 considered the presence of RAEs in 1474 ski jumping, 7501 cross-country skiing, 15,565 alpine skiing, 4179 snowboarders and 713 Nordic combined athletes. Chi-square analyses revealed significant RAEs for most of these contexts across sexes. In Study 2, RAEs in the aesthetic sports of figure skating (n=502) and female gymnastics (n=612) were considered. There was no effect for the figure skaters and an atypical effect for the gymnasts. The significant effects across most ski sports coupled with the null effects in figure skating and atypical effect in gymnastics suggest that sport-specific contextual factors are important elements in understanding the mechanisms of RAEs, although further work is necessary to validate these findings.
Full Text Available Purpose: compare the test results obtained at different stages of physical training of tourists skiers, immediately after passing of the ski sports hiking of the third category of complexity and 14 days after hiking. Determine the effectiveness of the designed program to improve the physical readiness of 30–40 years old tourists skiers. Material and Methods: 14 people aged 30 to 40 years old who have a different experience in water, hiking and mountain as well as ski-sport hiking took part in research. Analysis of scientific and methodical literature, pedagogical observations, pedagogical experiment, methods of mathematical statistics is used. Results: the test results of 30–40 years old tourists skiers which are the participants in the experimental group received at different stages of preparation and preparatory period and the results after passing ski sports hiking of the third category of complexity are processed. Their comparative analysis is held. Conclusions: it was found that the developed training program can effectively influence the physical readiness of tourists skiers, as well as all functions and systems that contribute to the successful passage of ski sports categorized hike.
Swinson, Derek B.
Presents examples of physics as applied to the sport of skiing. Examples examine the physics of sliding, unweighting, ski turning, wind resistance, the parabolic and circular motion of aerial skiers, and the aerial maneuvers of ski jumpers. (MDH)
Full Text Available Purpose: compare indicators of testing tourist skiers at different stages of the preparatory period to ski sports hike of third grade. Determine the effectiveness of training programs created to the tourists Categorical ski sports to prevent injuries and accidents in a limited time. Material: The study involved 13 people aged from 21 to 65 (4 women and 9 men with different experiences of hiking trails and various levels of total tourist preparedness. Results: The test results obtained before beginning the process of preparation are treated upon its completion, and immediately after passing categorical hike. In practice, the effectiveness of the proposed training programs of tourists to ski sports tours is proved. Conclusions : The created program can be recommended to tourist clubs, associations and organizations as the base in preparation for ski sports campaigns for the prevention of accidents and injuries.
Chenoweth, Karin; Evelyn, Jamilah
Announces the Sports Scholars Awards for 1998. One male and one female college athlete are profiled, and others are named for baseball, softball, basketball, fencing, riflery, bowling, football, wrestling, soccer, lacrosse, field hockey, swimming/diving, gymnastics, crew, tennis, golf, volleyball, track/field, cross country, downhill skiing, and…
Skiing and skiing techniques were introduced by the Austrians to Japanese soldiers in 1911. After that, skiing spread beyond the original purpose and recently produced the ski sciences. From a sports biomechanical aspect, the development of the study of ski jumping, alpine skiing, and the basic movement in skiing is introduced in this paper. One of the characteristic points of these studies in Japan was that the ski sciences were supported not only by biomechanists and physiologists, but also basically by physicists and engineers. The fundamental research and studies from divergent fields are supporting each other and being integrated into ski science.
From 22 to 29 January, the ski resort of La Clusaz in Haute Savoie hosted the 11th Winter Atomiades. With nine gold medals and four silver medals in cross-country skiing, and a bronze medal in downhill skiing, the team from the CERN Ski Club finished third in the medals table. Group photo at the 2011 Atomiades Organised by the Association of Sports Communities of European Research Institutes, nearly 260 participants from 15 research centres throughout Europe competed against each other in this skiing event. Each in their own discipline and age category, the fourteen members of the CERN team defended the colours of the Organization in the spirit of fun and fair play: “I had a really good week,” explained Simone Campana from the IT Department. “There was a great atmosphere. I’m only sorry that there was no general ranking this year. Let’s hope they’ll think about having one next time!” Despite the competition, the event is ...
Full Text Available Skiing on the glaciers has emerged as one more of the prominent and interesting representatives of unusual and relatively young extreme discipline. His appearance has reflected at the same time on the direction of the tourist group, which are rightfully called the adrenaline lovers or adventurers (in the broadest sense. All this has contributed to expanding the current tourism and sports exploited space, stirring the limits of human movement high, ie. deep in the untouched area of permafrost. In the paper are noted the facts of the genesis of the glacier, the conditions that prevailing at this height (ie. improvised tracks, and of numerous effects that the presence of visitors leave on this particularly sensitive and specific eco-system. In the framework of the paper was conducted a research about the possible interest and awareness of domestic tourists (in the area of Novi Sad for this kind of active rest. The idea was to present data which suggest to a certain conclusions on these issues, with the aim of determining the relationship of citizens of Serbia to the current trends in the field of sports and recreational tourism (having in mind the objective possibility of taking an participate in the category of special travel arrangements, material restrictions and difficulties in implementation of the same by the tour. A general task of the paper was to draw the attention of respondents to the chosen topic indirectly, and that among the educated and professionally qualified persons from the world of sports and tourism, additionally promote the new direction of global interest in the domain of extreme and adventure sports. Viewed from another aspect, it is about desire to foster thinking on the possibilities and purposes of further commercialization of worldwide trend in our area (at a higher level than the existing one.
Castanier, Carole; Le Scanff, Christine; Woodman, Tim
We investigated the risk-taking behaviors of 302 men involved in high-risk sports (downhill skiing, mountaineering, rock climbing, paragliding, or skydiving). The sportsmen were classified using a typological approach to personality based on eight personality types, which were constructed from combinations of neuroticism, extraversion, and…
Skiing is a fast and competitive sport where skiers must push their performance limit to win medals, the di↵erence can be within hundreds of a second. Therefore, technical improvements are essential for assisting in the skier’s improvement. This thesis project is a joint project between KTH and the Swedish Ski Association and Swedish Ski Team with the purpose of obtaining a better understanding of the structural properties of alpine skis, aiming to improve the individual selection process of ...
Sandbakk, Øyvind; Rasdal, Vegard; Bråten, Steinar; Moen, Frode; Ettema, Gertjan
To compare sport-specific laboratory capacities and the annual training of world-class Nordic combined (NC) athletes with specialized ski jumpers (SJ) and cross-country (XC) skiers. Five world-class athletes from each sports discipline were compared. Ski jump imitations were performed on a 3-dimensional force plate in NC athletes and SJ, whereas XC skiing characteristics were obtained from submaximal and maximal roller ski skating on a treadmill in NC athletes and XC skiers. In addition, anthropometrics and annual training characteristics were determined. NC athletes demonstrated 9% higher body mass and showed 17% lower vertical speed in the ski jump imitation than SJ (all P ski-jumping-specific sessions and outdoor ski jumps compared with SJ. NC athletes performed 31% less endurance training, mainly caused by lower amounts of low- and moderate-intensity training in the classical technique, whereas high-intensity strength and speed training and endurance training in the skating technique did not differ substantially from XC skiers. To simultaneously optimize endurance, explosive, and technical capacities in 2 different disciplines, world-class NC athletes train approximately two-thirds of the XC skier's endurance training volume and perform one-half of the ski-jump-specific training compared with SJ. Still, the various laboratory capacities differed only 10-17% compared with SJ and XC skiers.
Full Text Available Abstract Background Up to date, no information exists about the intra-articular temperature changes of the knee related to activity and ambient temperature. Methods In 6 healthy males, a probe for intra-articular measurement was inserted into the notch of the right knee. Each subject was jogging on a treadmill in a closed room at 19°C room temperature and skiing in a ski resort at -3°C outside temperature for 60 minutes. In both conditions, temperatures were measured every fifteen minutes intra-articulary and at the skin surface of the knee. A possible influence on joint function and laxity was evaluated before and after activity. Statistical analysis of intra-articular and skin temperatures was done using nonparametric Wilcoxon's sign rank sum test and Mann-Whitney's-U-Test. Results Median intra-articular temperatures increased from 31.4°C before activity by 2.1°C, 4°C, 5.8°C and 6.1°C after 15, 30, 45 and 60 min of jogging (all p ≤ 0.05. Median intra-articular temperatures dropped from 32.2°C before activity by 0.5°C, 1.9°C, 3.6°C and 1.1°C after 15, 30, 45 and 60 min of skiing (all n.s.. After 60 minutes of skiing (jogging, the median intra-articular temperature was 19.6% (8.7% higher than the skin surface temperature at the knee. Joint function and laxity appeared not to be different before and after activity within both groups. Conclusion This study demonstrates different changes of intra-articular and skin temperatures during sports in jogging and alpine skiing and suggests that changes are related to activity and ambient temperature.
Haynes Teresa W.
Full Text Available A path π = (v1, v2, . . . , vk+1 in a graph G = (V,E is a downhill path if for every i, 1 ≤ i ≤ k, deg(vi ≥ deg(vi+1, where deg(vi denotes the degree of vertex vi ∈ V. The downhill domination number equals the minimum cardinality of a set S ⊆ V having the property that every vertex v ∈ V lies on a downhill path originating from some vertex in S. We investigate downhill domination numbers of graphs and give upper bounds. In particular, we show that the downhill domination number of a graph is at most half its order, and that the downhill domination number of a tree is at most one third its order. We characterize the graphs obtaining each of these bounds
Akyüz, Murat; Agar, Muharrem; Akyüz, Öznur; Dogru, Yeliz
The aim of this study is to research the motivational factors affecting athletes to select the branches of athletics, ski and tennis. Within the scope of the research, the survey developed by H. Sunay in 1996 was implemented and solution for the problem of the research was searched through the findings that were obtained from the survey. SPSS…
Full Text Available The rational method of the speed-up teaching of students of flat rate of discipline is certain «Ski sport» to on to credit-module to the system. 60 students took part in an experiment. In basis of the speed-up teaching fixed integrally-separate going near mastering and perfection of technique of methods of movement on pattens. Optimum correlation of employments is set at teaching the technique of classic and skating styles of movement on pattens taking into account морфо-функциональных and physical qualities of students.
Hébert-Losier, Kim; Supej, Matej; Holmberg, Hans-Christer
Alpine ski racing is a popular international winter sport that is complex and challenging from physical, technical, and tactical perspectives. Despite the vast amount of scientific literature focusing on this sport, including topical reviews on physiology, ski-snow friction, and injuries, no review has yet addressed the biomechanics of elite alpine ski racers and which factors influence performance. In World Cup events, winning margins are often mere fractions of a second and biomechanics may well be a determining factor in podium place finishes. The aim of this paper was to systematically review the scientific literature to identify the biomechanical factors that influence the performance of elite alpine ski racers, with an emphasis on slalom, giant slalom, super-G, and downhill events. Four electronic databases were searched using relevant medical subject headings and key words, with an additional manual search of reference lists, relevant journals, and key authors in the field. Articles were included if they addressed human biomechanics, elite alpine skiing, and performance. Only original research articles published in peer-reviewed journals and in the English language were reviewed. Articles that focused on skiing disciplines other than the four of primary interest were excluded (e.g., mogul, ski-cross and freestyle skiing). The articles subsequently included for review were quality assessed using a modified version of a validated quality assessment checklist. Data on the study population, design, location, and findings relating biomechanics to performance in alpine ski racers were extracted from each article using a standard data extraction form. A total of 12 articles met the inclusion criteria, were reviewed, and scored an average of 69 ± 13% (range 40-89%) upon quality assessment. Five of the studies focused on giant slalom, four on slalom, and three on downhill disciplines, although these latter three articles were also relevant to super-G events
Edlund, G; Gedda, S; Hemborg, A
This paper evaluates 420 ski injuries occurring in Northern Sweden in 1977. Our main aim was to correlate knee injuries with types of skiing and to note a change in incidence with evolution of equipment. Fifty-eight lesions (13.8%) affected the knee joint which is about the same frequency as 10 years earlier nor has introduction of high stiff boots in downhill skiing increased incidence of knee injuries. Cross-country and long-distance skiing produced more knee injuries (24.7%) than downhill skiing (11.4%). Cross-country skiers were older and more women in this group sustained knee injuries. The use of non-release type bindings is probably the main reason for this higher incidence but age and different skiing techniques seem to contribute.
Gilgien, Matthias; Kröll, Josef; Spörri, Jörg; Crivelli, Philip; Müller, Erich
External forces, such as ground reaction force or air drag acting on athletes' bodies in sports, determine the sport-specific demands on athletes' physical fitness. In order to establish appropriate physical conditioning regimes, which adequately prepare athletes for the loads and physical demands occurring in their sports and help reduce the risk of injury, sport-and/or discipline-specific knowledge of the external forces is needed. However, due to methodological shortcomings in biomechanical research, data comprehensively describing the external forces that occur in alpine super-G (SG) and downhill (DH) are so far lacking. Therefore, this study applied new and accurate wearable sensor-based technology to determine the external forces acting on skiers during World Cup (WC) alpine skiing competitions in the disciplines of SG and DH and to compare these with those occurring in giant slalom (GS), for which previous research knowledge exists. External forces were determined using WC forerunners carrying a differential global navigation satellite system (dGNSS). Combining the dGNSS data with a digital terrain model of the snow surface and an air drag model, the magnitudes of ground reaction forces were computed. It was found that the applied methodology may not only be used to track physical demands and loads on athletes, but also to simultaneously investigate safety aspects, such as the effectiveness of speed control through increased air drag and ski-snow friction forces in the respective disciplines. Therefore, the component of the ground reaction force in the direction of travel (ski-snow friction) and air drag force were computed. This study showed that (1) the validity of high-end dGNSS systems allows meaningful investigations such as characterization of physical demands and effectiveness of safety measures in highly dynamic sports; (2) physical demands were substantially different between GS, SG, and DH; and (3) safety-related reduction of skiing speed might be
Schmitt, H; Gerner, H J
To examine the causes of sport-related spinal cord injuries that developed into paraplegia or tetraplegia, and to compare data from different sports with previous studies in the same geographical region. A retrospective epidemiological study and comparison with previous studies. The Orthopedic Department, specializing in the treatment and rehabilitation of paralyzed patients, at the University of Heidelberg, Germany. Between 1985 and 1997, 1,016 cases of traumatic spinal cord injury presented at the Orthopedic Department at the University of Heidelberg: 6.8% were caused by sport and 7.7% by diving accidents. Sport-related spinal cord injuries with paralysis. A total of 1.016 cases of traumatic spinal cord injury were reviewed. Of these, 14.5% were caused by sport accidents (n = 69) or diving accidents (n = 78). Age of patients ranged from 9 to 52 years. 83% were male. 77% of the patients developed tetraplegia, and 23%, paraplegia. 16 of the sport accidents resulted from downhill skiing, 9 resulted from horseback riding, 7 from modern air sports, 6 from gymnastics, 5 from trampolining, and 26 from other sports. Previous analyses had revealed that paraplegia had mainly occurred from gymnastics, trampolining, or high diving accidents. More recently, however, the number of serious spinal injuries caused by risk-filled sports such as hang gliding and paragliding has significantly increased (p = 0.095), as it has for horseback riding and skiing. Examinations have shown that all patients who were involved in diving accidents developed tetraplegia. An analysis of injury from specific sports is still under way. Analysis of accidents resulting in damage to the spinal cord in respect to different sports shows that sports that have become popular during the last 10 years show an increasing risk of injury. Modern air sports hold the most injuries. Injury-preventing strategies also are presented.
Çileroğlu, Birsen; Kelleci Özeren, Figen; Kıvılcımlar, İnci Seda
Popularity of Ski Sport in 19th century necessitated a new perspective on protective skiing clothing against the mountain climates and excessive cold. Winter clothing were the basis of ski attire during this period. By the beginning of 20th century lining cloth were used to minimize the wind effect. The difference between the men and women’s ski attire of the time consisted of a knee-length skirts worn over the golf trousers. Subsequent to the First World War, skiing suit models were influe...
For it 50 anniversary the ski club CERN organise a conference the Wednesday 23th of January from 7:00 pm to 8:30 pm in the council room at CERN. The subject of the conference will be : « Approche scientifique du ski : de la perception à l’action… », by Nicolas Coulmy, responsible of the technical and scientific department of the French Federation of Ski.
Gym Comme chaque année, la première activité à reprendre du service au SKI Club du CERN est la gymnastique ; les cours reprendront le mardi 17 septembre prochain. Si vous voulez améliorer votre condition physique en vue de la prochaine saison de ski (alpin ou de fond, ou snowboard), venez participer à nos cours au CO La Golette à Meyrin. Vous pouvez déjà vous inscrire en vous rendant sur le site du Ski club : http://cern.ch/club-ski/.
A physically-based water and energy balance model is used to simulate natural snow accumulation at 247 winter recreation locations across the continental United States. We combine this model with projections of snowmaking conditions to determine downhill skiing, cross-country ski...
Full Text Available Popularity of Ski Sport in 19th century necessitated a new perspective on protective skiing clothing ag ainst the mountain climates and excessive cold. Winter clothing were the basis of ski attire during this period. By the beginning of 20th century lining cloth were used to minimize the wind effect. The difference between the men and women’s ski attire of the time consisted of a knee - length skirts worn over the golf trousers. Subsequent to the First World War, skiing suit models were influenced by the period uniforms and the producers reflected the fashion trends to the ski clothing. In conformance with th e prevailing trends, ski trousers were designed and produced for the women thus leading to reduction in gender differences. Increases in the ski tourism and holding of the first winter olympics in 1924 resulted in variations in ski attires, development of design characteristics, growth in user numbers, and enlargement of production capacities. Designers emphasized in their collections combined presence of elegance and practicality in the skiing attire. In 1930s, the ski suits influenced by pilots’ uniforms included characteristics permitting freedom of motion, and the design elements exhibited changes in terms of style, material and aerodynamics. In time, the ski attires showed varying design features distinguishing professionals from the amateurs. While protective functionality was primary consideration for the amateurs, for professionals the aerodynamic design was also a leading factor. Eventually, the increased differences in design characteristics were exhibited in ski suit collections, World reknown brands were formed, production and sales volumes showed significant rise. During 20th century the ski suits influenced by fashion trends to acquire unique styles reached a position of dominance to impact current fashion trends, and apart from sports attir es they became a style determinant in the clothing of cold climates. Ski suits
As one of the most widespread sports discipline in Slovenia, ski jumping has a long tradition. Ski jumping is a competitive sport at which recreational engagement is not possible because of its special features and specifics. It is one of the basic sports activities for the development of children's motor skills, since ski jumping requires an integrated training of the trainee. Ski jumping is basically a winter sport, whereas in the summer season, it has also become increasingly present with ...
Full Text Available John F Moxnes,1 Øyvind Sandbakk,2 Kjell Hausken31Department for Protection, Norwegian Defence Research Establishment, Kjeller, Norway; 2Center for Elite Sports Research, Department of Neuroscience, Norwegian University of Science and Technology, Trondheim, Norway; 3Faculty of Social Sciences, University of Stavanger, Stavanger, NorwayAbstract: The current study adapts the power balance model to simulate cross-country skiing on varying terrain. We assumed that the skier’s locomotive power at a self-chosen pace is a function of speed, which is impacted by friction, incline, air drag, and mass. An elite male skier’s position along the track during ski skating was simulated and compared with his experimental data. As input values in the model, air drag and friction were estimated from the literature based on the skier's mass, snow conditions, and speed. We regard the fit as good, since the difference in racing time between simulations and measurements was 2 seconds of the 815 seconds racing time, with acceptable fit both in uphill and downhill terrain. Using this model, we estimated the influence of changes in various factors such as air drag, friction, and body mass on performance. In conclusion, the power balance model with locomotive power as a function of speed was found to be a valid tool for analyzing performance in cross-country skiing.Keywords: air drag, efficiency, friction coefficient, speed, locomotive power
René Oberli, un très bon ami et un des membres importants des débuts du Ski Club CERN est décédé à Noël 2011. Membre co-fondateur du Ski Club CERN en 1963, René Oberli a été 13 ans au comité dont 11 ans en tant que président. Grace à son action, le Ski Club a pris de l’ampleur, et était devenu un club actif et familial, proposant des cours de ski pour enfants et adultes, des week-ends de ski, des randonnées pédestres en été. René était aussi un moniteur de ski très apprécié et a enseigné le ski pendant de longues années. Nous nous souviendrons de sa grande compétence, de sa gentillesse, de sa bonne humeur et de son enthousiasme.
The Ski Club CERN invites you to a Public Information Meeting Thursday, 8th November at 6:30 pm Filtration Plant (222/R–001) for the presentation of its activities during the season 2012/2013. After the presentation, the people responsible for the different sections will be available to answer your questions and to provide you with detailed information about our activities. Come and learn more about our club over a drink! For more information on our activities please have look at our web site: http://club-ski.web.cern.ch/club-ski/
The Ski Club CERN invites you to a Public Information Meeting Thursday, 3rd November at 6:30 pm Council Chamber (503/1–001) for the presentation of its activities during the season 2011/2012. After the presentation, the people responsible for the different sections will be available to answer your questions and to provide you with detailed information about our activities. Come and learn more about our club over a drink! For more information on our activities please have look at our web site: http://club-ski.web.cern.ch/club-ski/
The registration for the ski season 2013-2014 is open. The standard permanences for the inscriptions will start: Thursday, November 14th at 6 pm CERN, Restaurant 2 (Bldg 504) (1st floor) Old members can collect their Carte neige from the 28th of november. New members and members who did not have a carte neige before must produce a medical certificate certifying that there are no medical reasons for which they should not be allowed to ski (french (legally correct) formulation : certificat médical de "non-contre indication à la pratique du ski"). You can obtain one from your family doctor.
Pfister, Gertrud Ursula
in winter. She also learned ski jumping. The little information that is available about her skiing activities clearly demonstrates that this sport played a key role in her life. Besides perfectly keeping up with her self-image as a competent woman, skiing provided her with the opportunity of escaping normal...
Full Text Available The objective of this study is the history of skiing, while the main goal will be the historical development of skiing in Montenegro. The study consists three goals. The first goal is the emergence of the first ski in the world and benefits that are brought. Another goal is focused on the development of skiing in the former Yugoslavia. The third and the main goal is the occurrence and development of skiing and ski sports in the territory of Montenegro. During the making of this study, the author used descriptive method with consulting of competent literature. The previous author experience in this field was also so useful. Moreover, the author used the analytic method and parallel method that is the most productive if you make some inferences about some appearance. Consequently, the main outcome of this study was showing of historical progress of ski sports in Montenegro from early beginnings to the modern Olympic skiing.
The ski season 2015-2016 is approaching! An information evening will take place: Thursday, November 5th, at 6.30 pm in the Salle de Pas Perdus (next to the Council Chamber) Online registration to the Ski Club activities will open the same evening at http://cern.ch/club-ski. Regular permanences will take place every Thursday starting with November 12th, at 6 pm in the 1st floor of Bld. 504 (Restaurant 2). All members can collect their Carte Neige from the 26th of November. New members and members who did not have a Carte Neige before must provide when signing up a medical certificate certifying that there are no medical restrictions for practicing ski activities (French legally correct formulation: certificat médical de "non-contre indication à la pratique du ski"). You can obtain one from your family doctor: certificates in English, French, Italian, German, Spanish are accepted. Please note that you are the only responsible for the validity of your medical certificate ...
Sakamoto, Yuko; Sakuraba, Keishoku
The purpose of this study was to compare the injury patterns and incidence of snowboarding and ski boarding injuries with that of alpine skiing in 2000 to 2005, as there are few previous studies comparing these 3 sports, especially in Asia. The injury patterns are different among the 3 snow sports. Descriptive epidemiology study. The subjects were alpine skiers (1240 cases), snowboarders (2220 cases), and ski boarders (132 cases) who were injured in 2 ski resorts located in Niigata prefecture in Japan and visited the authors' clinics in these ski resorts between 2000 and 2005. On visiting the clinics, patients completed a questionnaire reviewing the circumstances surrounding the injury event, and physicians documented the diagnosis. The injury rate, which was based on all purchased lift tickets, in snowboarding decreased gradually, although it was still 2 times higher than that of alpine skiing. Snowboarding and ski boarding had a higher fracture and dislocation rate. Both sports also had a 4 times higher rate of injuries because of jumping. The characteristics of ski boarding were a lower head and neck injury rate and collision injury rate than those of the other 2 snow sports, as well as a 2 times higher rate of fractures compared with alpine skiing injuries and a 1.4 times higher incidence than that of snowboarding injuries. Of the fractures caused by ski boarding accidents, 39.6% affected the lower leg bones. Injury prevention strategies should focus on jumps for snowboarders and ski boarders.
Müller, Erich; Schwameder, Hermann
There have been considerable changes in equipment design and movement patterns in the past few years both in alpine skiing and ski-jumping. These developments have been matched by methods of analysing movements in field conditions. They have yielded new insights into the skills of these specific winter sports. Analytical techniques have included electromyography, kinetic and kinematic methods and computer simulations. Our aim here is to review biomechanical research in alpine skiing and ski-jumping. We present in detail the techniques currently used in alpine skiing (carving technique) and ski-jumping (V-technique), primarily using data from the authors' own research. Finally, we present a summary of the most important results in biomechanical research both in alpine skiing and ski-jumping. This includes an analysis of specific conditions in alpine skiing (type of turn, terrain, snow, speed, etc.) and the effects of equipment, materials and individual-specific abilities on performance, safety and joint loading in ski-jumping.
Full Text Available The objective of this study is the history of skiing, while the main goal will be the historical development of skiing in the mountain Durmitor area in Montenegro. The study consists two goals. The first goal is the emergence of the first ski in the Montenegro and benefits that are brought. The second and the main goal is the occurrence and development of skiing and ski sports in the territory of mountain Durmitor. During the making of this study, the authors used descriptive method with consulting of competent literature. The previous authors’ experience in this field was also so useful. Moreover, the author used the analytic method and parallel method that is the most productive if you make some inferences about some appearance. The main outcome of this study was showing of historical progress of ski sports in the territory of mountain Durmitor from early beginnings to the modern Olympic skiing. Skis and ski sport were early appeared in the region of Mount Durmitor. The mountain and the region around it, are very rich with slopes with Olympic diameter, with plenty of snowfall and long winters. However, lack of financial investment, channeling money to other centers, led to the fact that the skiing in this area is at a low level.
Le Docteur Kiebel, chirurgien à Genève, est aussi un grand ami de sport et de temps en temps médecin des classes genevoises de ski et également médecin de l'équipe de hockey sur glace de Genève Servette. Il est bien qualifié pour nous parler d'accidents de sport et surtout d'accidents de ski.
Keren, Amit; Berkovich, Yaron; Berkovitch, Yaron; Soudry, Michael
Joint arthroplasty is one of the commonest surgical procedures in orthopedic surgery. In recent years there was an increase in the number of procedures, patient satisfaction and implant survival. Originally, these operations were designed for old patients in order to relieve pain and to enable ambulation. Over the past few years, these operations have become common in younger patients which desire to return to activity, including sports activities. The importance of physical activity is a well known fact. In recent years it became clear that with the proper physical activity the outcomes of the operations are better. There are several types of arthroplasty. Many factors influence the outcome of the operation apart from the post-surgery physical activity. These factors include patient factors, surgical technique and type of arthroplasty. This review summarizes the recommendations for sports activities after hip and knee arthroplasties. These activities are evaluated according to surgeons' recommendations, stress applied on the implant and long term outcomes. The recommended sports activities after joint arthroplasties are walking, swimming and cycling. Soccer, basketball and jogging are not advised. Tennis, downhill skiing and horse riding are recommended with previous experience. There are many more sports activities that patients can participate in, and it is important that the patient discuss the different options prior to the operation. Since these operations are so common, many non-orthopedic physicians encounter these patients in their practice. They should be acquainted with the recommendations for sports activities and encourage them.
Norwich, Andreas Tørum
Background: The concept of core stability and balance are emphasized during athletic training for Norwegian ski jumpers. The impression of how important it can be for sport performance has long been a matter of interest within research. The purpose of this study was to examine the association between core stability, balance and ski-jumping performance ability in competitive ski jumpers. Methods: Eleven male ski jumpers were tested for steadiness in two commonly used core exercises (plank a...
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Wright, J R; McIntyre, L; Rand, J J; Hixson, E G
Little data are available in the medical literature on nordic ski jumping injuries. Injury questionnaires were sent to all active American ski jumpers registered either with the United States Ski Association or with a jumping club registered with the United States Ski Association. One hundred thirty-three of 286 (46.5%) injury questionnaires were returned. Eighty-one of the 133 respondents (60.9%) had been injured sufficiently to require examination by a physician at least once during their jumping careers. This report describes the types and frequencies of injuries sustained by this group of nordic ski jumpers as well as provides demographic data about American ski jumpers. The risk of injury per 100 participant years was 9.4, a rate less than that reported for most high school or college intermural sports.
Burr, Jamie F; Drury, C Taylor; Ivey, Adam C; Warburton, Darren E R
Mountain biking is a popular recreational pursuit and the physiological demands of cross-country style riding have been well documented. However, little is known regarding the growing discipline of gravity-assisted downhill cycling. We characterised the physiological demands of downhill mountain biking under typical riding conditions. Riding oxygen consumption (VO(2)) and heart rate (HR) were measured on 11 male and eight female experienced downhill cyclists and compared with data during a standardised incremental to maximum (VO(2max)) exercise test. The mean VO(2) while riding was 23.1 ± 6.9 ml · kg(-1) · min(-1) or 52 ± 14% of VO(2max) with corresponding heart rates of 146 ± 11 bpm (80 ± 6% HRmax). Over 65% of the ride was in a zone at or above an intensity level associated with improvements in health-related fitness. However, the participants' heart rates and ratings of perceived exertion were artificially inflated in comparison with the actual metabolic demands of the downhill ride. Substantial muscular fatigue was evident in grip strength, which decreased 5.4 ± 9.4 kg (5.5 ± 11.2%, P = 0.03) post-ride. Participation in downhill mountain biking is associated with significant physiological demands, which are in a range associated with beneficial effects on health-related fitness.
Gilgien, Matthias; Kröll, Josef; Spörri, Jörg; Crivelli, Philip; Müller, Erich
External forces, such as ground reaction force or air drag acting on athletes' bodies in sports, determine the sport-specific demands on athletes' physical fitness. In order to establish appropriate physical conditioning regimes, which adequately prepare athletes for the loads and physical demands occurring in their sports and help reduce the risk of injury, sport-and/or discipline-specific knowledge of the external forces is needed. However, due to methodological shortcomings in biomechanical research, data comprehensively describing the external forces that occur in alpine super-G (SG) and downhill (DH) are so far lacking. Therefore, this study applied new and accurate wearable sensor-based technology to determine the external forces acting on skiers during World Cup (WC) alpine skiing competitions in the disciplines of SG and DH and to compare these with those occurring in giant slalom (GS), for which previous research knowledge exists. External forces were determined using WC forerunners carrying a differential global navigation satellite system (dGNSS). Combining the dGNSS data with a digital terrain model of the snow surface and an air drag model, the magnitudes of ground reaction forces were computed. It was found that the applied methodology may not only be used to track physical demands and loads on athletes, but also to simultaneously investigate safety aspects, such as the effectiveness of speed control through increased air drag and ski–snow friction forces in the respective disciplines. Therefore, the component of the ground reaction force in the direction of travel (ski–snow friction) and air drag force were computed. This study showed that (1) the validity of high-end dGNSS systems allows meaningful investigations such as characterization of physical demands and effectiveness of safety measures in highly dynamic sports; (2) physical demands were substantially different between GS, SG, and DH; and (3) safety-related reduction of skiing speed might
Full Text Available External forces, such as ground reaction force or air drag acting on athletes' bodies in sports, determine the sport-specific demands on athletes' physical fitness. In order to establish appropriate physical conditioning regimes, which adequately prepare athletes for the loads and physical demands occurring in their sports and help reduce the risk of injury, sport-and/or discipline-specific knowledge of the external forces is needed. However, due to methodological shortcomings in biomechanical research, data comprehensively describing the external forces that occur in alpine super-G (SG and downhill (DH are so far lacking. Therefore, this study applied new and accurate wearable sensor-based technology to determine the external forces acting on skiers during World Cup (WC alpine skiing competitions in the disciplines of SG and DH and to compare these with those occurring in giant slalom (GS, for which previous research knowledge exists. External forces were determined using WC forerunners carrying a differential global navigation satellite system (dGNSS. Combining the dGNSS data with a digital terrain model of the snow surface and an air drag model, the magnitudes of ground reaction forces were computed. It was found that the applied methodology may not only be used to track physical demands and loads on athletes, but also to simultaneously investigate safety aspects, such as the effectiveness of speed control through increased air drag and ski–snow friction forces in the respective disciplines. Therefore, the component of the ground reaction force in the direction of travel (ski–snow friction and air drag force were computed. This study showed that (1 the validity of high-end dGNSS systems allows meaningful investigations such as characterization of physical demands and effectiveness of safety measures in highly dynamic sports; (2 physical demands were substantially different between GS, SG, and DH; and (3 safety-related reduction of skiing
Lenamar Fiorese Vieira
Full Text Available Este estudo teve como objetivo investigar a prevalência do estado de fluxo em praticantes de escalada e skate downhill. Foram sujeitos 37 praticantes. Como instrumentos foram utilizadas a Escala de Motivação para o Esporte (SMS e a Ficha de Percepção de Capacidade de Realização da Tarefa. A coleta foi realizada nos locais de prática das atividades. Para análise dos dados foram utilizados Shapiro-Wilk, Mann-Whitney e Anova one-way. Os resultados demonstraram: 4,54% dos praticantes de escalada e 13,33% de skate downhill atingiram os elementos do estado de fluxo; a maioria dos praticantes situou-se entre a fase de fluxo estados de ansiedade ou relaxamento e exaltação ou controle; o tempo de prática contribuiu para atingir metas e estado de fluxo. Concluiu-se: o estado de Fluxo teve baixa incidência nos praticantes, havendo interferência da falta de equilíbrio entre percepção das metas, habilidades e desafios nas atividades de aventura.This study aimed to investigate the prevalence of Flow state in climbing and skate downhill practitioners. The subjects were 37 practitioners. The instruments used were the Sport Motivations Scale (SMS and Perception Capacity Achievement Task Form. Data collection was performed at the locations of these practice activities. For data analysis it was used the Shapiro-Wilk, Mann-Whitney and Anova one-way. The results showed: 4,54% of climbing practitioners and 13,33% of skate-downhill reached flow state elements; most of practitioners prevailed between the flow phase of anxiety or relaxation and phase of exaltation or control; and the practice time contributed to reach goals and Flow State. It was concluded that the Flow State had low prevalence in practitioners with interference of lack of balance between the perception of the goals, skills and challenges in the adventure activities.
Gilgien, Matthias; Spörri, Jörg; Kröll, Josef; Crivelli, Philip; Müller, Erich
In alpine ski racing, there is limited information about skiers' mechanical characteristics and their relation to injury risk, in particular for World Cup (WC) competitions. Hence, current findings from epidemiological and qualitative research cannot be linked to skiers' mechanics. This study was undertaken to investigate whether recently reported differences in numbers of injuries per 1000 runs for competition disciplines can be explained by differences in the skiers' mechanics. During seven giant slalom, four super-G and five downhill WC competitions, mechanical characteristics of a forerunner were captured using differential global navigation satellite technology and a precise terrain surface model. Finally, the discipline-specific skiers' mechanics were compared with the respective number of injuries per hour skiing. While the number of injuries per hour skiing was approximately equal for all disciplines, kinetic energy, impulse, run time, turn radius and turn speed were significantly different and increased from giant slalom to super-G and downhill. Turn ground reaction forces were largest for giant slalom, followed by super-G and downhill. The number of jumps was doubled from super-G to downhill. Associating the number of injuries per hour in WC skiing with skiers' mechanical characteristics, injuries in super-G and downhill seem to be related to increased speed and jumps, while injuries in giant slalom may be related to high loads in turning. The reported differences in the number of injuries per 1000 runs might be explained by a bias in total exposure time per run and thus potentially by emerged fatigue.
Horne, J.; Cockshott, W.P.; Shannon, H.S.
We conducted a radiographic survey of 117 competitive water ski jumpers to determine whether this sport can cause spinal column damage and, if so, whether damage is more likely to occur in those who participate during the period of spinal growth and development (age 15 years or younger). We found a high prevalence of two types of abnormality: Scheuermann (adolescent) spondylodystrophy (present in 26% of the skiers) and vertebral body wedging (present in 34%). The prevalence of adolescent spondylodystrophy increased with the number of years of participation in the sport before age 15 years or less. Of those in this age group who had skied for 5 years or more, 57 showed adolescent spondylodystrophy; of those in the same age group who had skied for 9 years or more, 100% were affected. Wedged vertebrae increased as time of participation increased, regardless of the age at which exposure began. We conclude that competitive water ski jumping may damage the spinal column and that consideration should be given to regulating this sport, particularly for children. (orig.)
Horne, J; Cockshott, W P; Shannon, H S
We conducted a radiographic survey of 117 competitive water ski jumpers to determine whether this sport can cause spinal column damage and, if so, whether damage is more likely to occur in those who participate during the period of spinal growth and development (age 15 years or younger). We found a high prevalence of two types of abnormality: Scheuermann (adolescent) spondylodystrophy (present in 26% of the skiers) and vertebral body wedging (present in 34%). The prevalence of adolescent spondylodystrophy increased with the number of years of participation in the sport before age 15 years or less. Of those in this age group who had skied for 5 years or more, 57 showed adolescent spondylodystrophy; of those in the same age group who had skied for 9 years or more, 100% were affected. Wedged vertebrae increased as time of participation increased, regardless of the age at which exposure began. We conclude that competitive water ski jumping may damage the spinal column and that consideration should be given to regulating this sport, particularly for children.
Horne, J.; Cockshott, W.P.; Shannon, H.S.
We conducted a radiographic survey of 117 competitive water ski jumpers to determine whether this sport can cause spinal column damage and, if so, whether damage is more likely to occur in those who participate during the period of spinal growth and development (age 15 years or younger). We found a high prevalence of two types of abnormality: Scheuermann (adolescent) spondylodystrophy (present in 26% of the skiers) and vertebral body wedging (present in 34%). The prevalence of adolescent spondylodystrophy increased with the number of years of participation in the sport before age 15 years or less. Of those in this age group who had skied for 5 years or more, 57 showed adolescent spondylodystrophy; of those in the same age group who had skied for 9 years or more, 100% were affected. Wedged vertebrae increased as time of participation increased, regardless of the age at which exposure began. We conclude that competitive water ski jumping may damage the spinal column and that consideration should be given to regulating this sport, particularly for children. (orig.)
Becker, Johannes; Runer, Armin; Neunhäuserer, Daniel; Frick, Nora; Resch, Herbert; Moroder, Philipp
Downhill mountain biking (DMB) has become an increasingly popular extreme sport in the last few years with high velocities and bold manoeuvres. The goal of this study was to provide information on the pattern and causes of injuries in order to provide starting points for injury prevention measures. We performed a monthly e-mail-based prospective survey of 249 riders over one summer season ranging from April until September 2011. A total of 494 injuries occurred during the 29 401 h of downhill exposure recorded, of these 65% were mild, 22% moderate and 13% severe, of which 41% led to a total restriction greater than 28 days. The calculated overall injury rate was 16.8 injuries per 1000 h of exposure. For experts it was 17.9 injuries per 1000 h of exposure, which is significantly higher than the 13.4 for professional riders (OR 1.34; 95% CI, 1.02 to 1.75; p=0.03). A significantly higher rate of injury was reported during competition (20 per 1000 h) than during practice (13 per 1000 h) (OR 1.53; 95% CI, 1.16 to 2.01; p=0.0022). The most commonly injured body site was the lower leg (27%) followed by the forearm (25%). Most frequent injury types were abrasions (64%) and contusions (56%). Main causes of injury reported by the riders were riding errors (72%) and bad trail conditions (31%). According to our data DMB can be considered an extreme sport conveying a high risk of serious injury. Strategies of injury prevention should focus on improvements in riders' technique, checking of local trail conditions and protective equipment design.
Flørenes, T W; Nordsletten, L; Heir, S; Bahr, R
There is little information available on injuries to World Cup skiers and snowboarders. The aim of this study was to describe and compare the injury risk to World Cup athletes in alpine skiing, freestyle skiing, snowboarding, ski jumping, Nordic combined and cross country skiing. We performed retrospective interviews with the International Ski Federation (FIS) World Cup athletes from selected nations during the 2006-2007 and 2007-2008 winter seasons and recorded all acute injuries occurring during the seasons. We interviewed 2121 athletes and recorded 705 injuries. There were 520 (72%) time-loss injuries and 196 (28%) severe injuries (absence >28 days). In freestyle skiing, alpine skiing and snowboarding, there were 27.6, 29.8 and 37.8 time-loss and 14.4, 11.3 and 13.8 severe injuries per 100 athletes per season, respectively. In Nordic combined, ski jumping and cross country skiing, there were 15.8, 13.6 and 6.3 time-loss and 3.3, 5.6 and 0.7 severe injuries per 100 athletes per season, respectively. In conclusion about 1/3 of the World Cup alpine, freestyle and snowboard athletes sustain a time-loss injury each season, while the risk is low in the Nordic disciplines. A particular concern was the high proportion of severe injuries observed among alpine, freestyle and snowboard athletes, which is in contrast to most other sports. © 2010 John Wiley & Sons A/S.
Loibl, Markus; Bäumlein, Martin; Massen, Felix; Gueorguiev, Boyko; Glaab, Richard; Perren, Thomas; Rillmann, Paavo; Ryf, Christian; Naal, Florian D
Tibial plateau fractures occur frequently while participating in winter sports, but there is no information on whether skiers can resume sports and recreational activities after internal fixation of these fractures. Skiers can resume low-impact sports activity after internal fixation of tibial plateau fractures. Case series; Level of evidence, 4. A total of 103 patients were surveyed by postal questionnaires to determine their sports activities at a mean of 7.8 ± 1.8 years after internal fixation of intra-articular tibial plateau fractures. The survey also included the Lysholm score, the Tegner activity scale, and a visual analog scale (VAS) for pain. At the time of the survey, 88% of the patients were engaged in sports activities (rate of return to sports, 88%), and 53% continued to participate in downhill skiing. The median number of different activities declined from 5 (range, 1-17) preoperatively to 4 (range, 0-11) postoperatively (P Sports frequency and duration per week did not change: 3 (range, 1-7) preoperatively versus 3 (range, 0-7) postoperatively (P = .275) and 4 hours (range, 1-16 hours) preoperatively versus 3.5 hours (range, 0-15 hours) postoperatively (P = .217), respectively. Median values of all outcome scores declined: Lysholm score, 100 (range, 85-100) preoperatively versus 94.5 (range, 37-100) postoperatively (P sports at the time of follow-up compared with the ability before the accident was rated as "similar" by 57 patients (62.0%) and as "worse" by 35 patients (38.0%). The more severe fracture types, B3 and C3 according to the AO classification system, were associated with poorer outcomes related to return to sports and functional scores. A large percentage of skiers with surgically treated intra-articular tibial plateau fractures cannot continue to participate in downhill skiing; however, the majority could resume an active lifestyle for several years after the trauma. Fracture type seems to be an important factor influencing physical
Full Text Available Alpine skiing is one of the most popular leisure time winter sporting activities. Skiing imposes high requirements concerning physical fitness, particularly regarding balance abilities. The main objective of this study was to evaluate the changes in balance performance of recreational skiers after a seven-day ski camp. A total of 78 students - 24 women and 54 men - participated in the study. The ski course was held in accordance with the official program of the Polish Ski Federation. The study sample was comprised of 43 beginners and 35 intermediate skiers. All students were tested with the MFT S3-Check, the day before and the day after the ski camp. The test system consisted of an unstable uniaxial platform, with an integrated sensor and corresponding software. Changes in balance performance (sensory and stability index were evaluated using paired t-tests. Additionally, changes in sensory and stability categories, which were based on the norm data, were analyzed. Female and male participants showed significantly better sensory and stability indices after skiing. Considerable changes from weak or very weak to average or good balance categories could be seen after skiing for both sexes. Regarding skiing experience, both beginners and intermediate skiers improved their sensory and stability indices significantly after skiing. Hence, recreational alpine skiing resulted in better balance performance regardless of sex or skiing experience. Skiing as an outdoor activity offers the opportunity to improve balance performance with a positive impact on everyday life activities.
Jordan, Matthew J; Aagaard, Per; Herzog, Walter
and return to sport after ACL injury in alpine ski racing. Given that most of the scientific studies on ACL injuries in alpine ski racing have been descriptive, and that very few studies contributed higher level scientific evidence, a nonsystematic narrative review was employed. Three scholarly databases...... were searched for articles on ACL injury or knee injury in alpine ski racing. Studies were classified according to their relevance in relation to epidemiology, etiology, risk factors, and return to sport/reinjury prevention. Alpine ski racers (skiers) were found to be at high risk for knee injuries...... injuries in development-level skiers, there was limited scientific data on ACL injury risk factors among elite skiers. Based on expert opinion, research on injury risk factors should focus on equipment design, course settings/speed, and athlete factors (eg, fitness). While skiers seem to make a successful...
Giulio Sergio Roi
Full Text Available The knee is the weight-bearing joint most commonly associated with sports injuries, and therefore is most at risk of developing degenerative changes, including osteoarthritis. Skyrunners can be considered to be at risk of developing symptoms of post-traumatic osteoarthritis due to downhill running.The aim of this study was to analyze the health of the knee joints of a large group of these athletes via a specific self-report questionnaire.This study was carried out by asking the participants of seven official Skyraces (22.4±3.1 km length; 1596±393 m elevation to fill out a questionnaire. Information regarding age, sex, downhill elevation (m during training and competitions over the last month, and history of previous knee injury was also collected before the participants filled out the Knee injury and Osteoarthritis Outcome Score (KOOS, which is a reliable and validated instrument designed to assess patients' opinions about their knees and associated problems that can result in post-traumatic osteoarthritis. Athletes were divided into six age groups (from 17 to 70 years and 12 groups based on the downhill gradient they had covered over the last month (from 1,000 to 40,000 m.Six hundred twenty-one questionnaires were collected from 45% of the participants in the seven races. Multivariate analysis revealed that self-reported KOOS scores were unrelated to age, sex and monthly downhill gradient. Only 74 (12% of the participants reported previous knee injuries. Significant differences in the five subscales of the KOOS were found between skyrunners with and without previous knee injuries (P<0.01.In the studied population, regular training for downhill running and participation in Skyraces could not be considered risk factors for subjective knee symptoms. Skyrunners with self-reported histories of knee injuries scored worse on all five subscales of the KOOS.
Wright, J R
Nordic ski-jumping fatalities are rare events. Six jumping fatalities have occurred in the United States during the past 50 years. The fatality rate for nordic ski jumping, estimated to be roughly 12 fatalities/100,000 participants annually, appears to be within the range of fatality rates for other "risky" outdoor sports. Cervical fractures appear to be the most frequent fatal ski-jumping injury.
Sweden has, since many years, an ongoing debate on nuclear power in general and nuclear safety and nuclear waste in particular. SKI is not the only part who wants to communicate about these subjects. The nuclear power plants, other authorities, the anti-nuclear groups and the politicians are other parts on the communication scene. The role of SKI is to provide the Swedish public with objective and prompt information based on facts. (author)
Tuggy, M L
Telemark skiing has become increasingly popular over the past 5 years. Telemark skiing poses unique risks when compared to alpine skiing, because of different equipment, technique, and varied skiing environments. A retrospective survey of telemark skiers was conducted in Western Washington in 1994 to obtain skier information on ski habits, demographics, frequency and types of injury, and equipment used at time of injury. During the 5 month survey period, 118 (63%) of 187 surveys distributed at 7 sites were returned. The overall injury rate was comparable to alpine skiing injury rates at 10.7/1000 skier days. Less experienced skiers and women had higher injury rates, 20/1000 and 13.1/1000 skier days, respectively. The predominant injury sites were knee (41%), hip (13%), and thumb (8%). The knee injuries sustained by telemark skiers appear to be less severe than alpine skiers, with less duration of disability and lower surgical rates. An association was found between the use of plastic reinforced boots and significant ligamentous knee injuries when compared to skiers with leather boots (p < 0.01, chi 2 = 5.43).
van Ginkel, S; Amami, M; Dela, F
Downhill skiing in the elderly increases maximal oxygen uptake (VO2max) and carbohydrate handling, and produces muscle hypertrophy. We hypothesized that adjustments of the cellular components of aerobic glucose combustion in knee extensor muscle, and cardiovascular adjustments, would increase...... lateralis muscle were analyzed for capillary density and expression of respiratory chain markers (NDUFA9, SDHA, UQCRC1, ATP5A1) and the glucose transporter GLUT4. Statistical significance was assessed with a repeated analysis of variance and Fisher's post-hoc test at a P value of 5%. VO2max increased...... selectively with ski training (+7 ± 2%). Capillary density (+11 ± 5%) and capillary-to-fiber ratio (12 ± 5%), but not the concentration of metabolic proteins, in vastus lateralis were increased after skiing. Cardiovascular parameters did not change. Fold changes in VO2max and capillary-to-fiber ratio were...
Full Text Available A decline in physiological functioning and mental wellbeing is common with advancing age. However, these changes may vary among elderly individuals. Physical activity and the response of the elderly to exercise during recreational activities, i.e., recreational alpine skiing, may serve as a catalyst for the improvement of wellbeing and general health. Purpose: The aim of the study was to assess the heart rate (HR response modulations in a group of elderly recreational alpine skiers during 3.5h of skiing. In addition, each group's perceived responses of mood state (MS and rating of perceived exertion (RPE were collected to determine possible contributions to changes in wellbeing as a result of recreational skiing. Methods: Forty-nine healthy elderly participants (mean age: 63±6 yrs, weight: 75.4+13.1 kg, height: 170.5+9.1 cm, BMI: 26+3.2 with at least basic alpine skiing ability participated in a 3.5h ski test. GPS data (GPS Garmin Forerunner 301 were used to monitor altitude and HR and were recorded continuously during the 3.5h of skiing. During skiing, participants were asked at three different times to report RPE and MS. Results: The time spent on the lift during the 3.5h skiing ranged from 21-58% followed by recovery breaks of 17-53% and time spent in downhill skiing ranged from 12-40%. Participants completed 9-23 downhill runs in 3.5h. Average intensities during 3.5 h downhill runs for over 80% of the group were between 50-80% of maximal heart rate (HRmax (220-age. Peak heart rate (HRpeak values during downhill runs for 35% of the group were between 60-70% of HRmax. Statistical analysis revealed numerous significant differences between RPE and MS values for the three different sampling times. The MS in general remained positive and even increased in the categories of happiness and sociability despite an increase in fatigue. Conclusion: The results of this study suggest that the duration and intensity of skiing was appropriate and yielded
Il paper si prefigge l’obiettivo di esaminare, sotto diversi profili, le regole di sicurezza e la responsabilità civile nascente dall’esercizio del mountain biking e del downhill, due attività sportive in grande espansione che costituiscono ormai un volano importante nelle strategie di marketing connesse alla fruizione turistica della montagna estiva. L’analisi si focalizza sulla evoluzione del fenomeno sportivo e turistico connessa a questi sport e sulle responsabilità nascenti in capo ai so...
Hurst, Howard T; Atkins, Stephen; Dickinson, Ben D
To determine the magnitude of translational and rotational head accelerations during downhill mountain biking. Observational study. Sixteen male downhill cyclists (age 26.4±8.4years; stature 179.4±7.2cm; mass 75.3±5.9kg) were monitored during two rounds of the British Downhill Series. Riders performed two runs on each course wearing a triaxial accelerometer behind the right ear. The means of the two runs for each course were used to determine differences between courses for mean and maximum peak translational (g) and rotational accelerations (rad/s 2 ) and impact duration for each course. Significant differences (p10g), FW=12.5±7.6, RYF=42.8±27.4 (t (22.96) =-4.70; p<0.001; 95% CI=17.00 to 43.64); maximum peak rotational acceleration, FW=6805.4±3073.8rad/s 2 , RYF=9799.9±3381.7rad/s 2 (t (32) =-2.636; p=0.01; 95% CI=680.31 to 5308.38); mean acceleration duration FW=4.7±1.2ms, RYF=6.5±1.4ms (t (32) =-4.05; p<0.001; 95% CI=0.91 to 2.76) and maximum acceleration duration, FW=11.6±4.5ms, RYF=21.2±9.1 (t (29.51) =-4.06; p=0.001; 95% CI=4.21 to 14.94). No other significant differences were found. Findings indicate that downhill riders may be at risk of sustaining traumatic brain injuries and course design influences the number and magnitude of accelerations. Copyright © 2018 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.
Johnson, Evan C; Pryor, J Luke; Casa, Douglas J; Belval, Luke N; Vance, James S; DeMartini, Julie K; Maresh, Carl M; Armstrong, Lawrence E
Determine if performance and physiological based pacing characteristics over the varied terrain of a triathlon predicted relative bike, run, and/or overall success. Poor self-regulation of intensity during long distance (Full Iron) triathlon can manifest in adverse discontinuities in performance. Observational study of a random sample of Ironman World Championship athletes. High performing and low performing groups were established upon race completion. Participants wore global positioning system and heart rate enabled watches during the race. Percentage difference from pre-race disclosed goal pace (%off) and mean HR were calculated for nine segments of the bike and 11 segments of the run. Normalized graded running pace (accounting for changes in elevation) was computed via analysis software. Step-wise regression analyses identified segments predictive of relative success and HP and LP were compared at these segments to confirm importance. %Off of goal velocity during two downhill segments of the bike (HP: -6.8±3.2%, -14.2±2.6% versus LP: -1.2±4.2%, -5.1±11.5%; p<0.020) and %off from NGP during one downhill segment of the run (HP: 4.8±5.2% versus LP: 33.3±38.7%; p=0.033) significantly predicted relative performance. Also, HP displayed more consistency in mean HR (141±12 to 138±11 bpm) compared to LP (139±17 to 131±16 bpm; p=0.019) over the climb and descent from the turn-around point during the bike component. Athletes who maintained faster relative speeds on downhill segments, and who had smaller changes in HR between consecutive up and downhill segments were more successful relative to their goal times. Copyright © 2013 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.
Virmavirta, Mikko; Kivekäs, Juha; Komi, Paavo
The effect of skis on the force-time characteristics of the simulated ski jumping takeoff was examined in a wind tunnel. Takeoff forces were recorded with a force plate installed under the tunnel floor. Signals from the front and rear parts of the force plate were collected separately to examine the anteroposterior balance of the jumpers during the takeoff. Two ski jumpers performed simulated takeoffs, first without skis in nonwind conditions and in various wind conditions. Thereafter, the same experiments were repeated with skis. The jumpers were able to perform very natural takeoff actions (similar to the actual takeoff) with skis in wind tunnel. According to the subjective feeling of the jumpers, the simulated ski jumping takeoff with skis was even easier to perform than the earlier trials without skis. Skis did not much influence the force levels produced during the takeoff but they still changed the force distribution under the feet. Contribution of the forces produced under the rear part of the feet was emphasized probably because the strong dorsiflexion is needed for lifting the skis to the proper flight position. The results presented in this experiment emphasize that research on ski jumping takeoff can be advanced by using wind tunnels.
Climatology and climate change have become central topics in Geography at our school. Because of that we set up a climatological station at our school. The data are an important basis to observe sudden changes in the weather. The present winter (2013/2014) shows the importance of climate change in Alzey / Germany. In winter many students think of the yearly skiing trip to Schwaz / Austria which is part of our school programme. Due to that the following questions arise: Will skiing still be possible if climate change accelerates? How are the skiing regions in the Alpes going to change? What will happen in about 20 years? How does artificial snow change the landscape and the skiing sport? Students have to be aware of the ecological damage of skiing trips. Each class has to come up with a concept how these trips can be as environmentally friendly as possible. - the trip is for a restricted number of students only (year 8 only) - a small skiing region is chosen which is not overcrowded - snow has to be guaranteed in the ski area to avoid the production of artificial snow (avoidance of high water consumption) - the bus arrives with a class and returns with the one that had been there before These are but a few ideas of students in order to make their trip as environmentally friendly as possible. What is missing is only what is going to happen in the future. What will be the effect of climate change for skiing regions in the secondary mountains? How is the average temperature for winter going to develop? Are there possibilities for summer tourism (e.g. hiking) instead of skiing in winter? The students are going to try to find answers to these questions which are going to be presented on a poster on the GIFT-Workshop in Vienna.
SKI's research is a prerequisite for SKI's ability to fulfil its assignment. Research to support supervision is focused today on a number of strategically important areas such as reactor technology, material and fuel questions, human factors, waste and non-proliferation (safeguards). SKI's intelligence analysis shows that this focus should be maintained over the next few years. Some reallocation of priorities between research areas may be necessary due to changes in the nuclear area. For this research, SKI contracts universities as well as consulting companies. The resources that are of importance for nuclear research are concentrated to a few organisations in Sweden. But the national research resources alone do not cover the existing needs. One reason is that the previously highly competent and well funded Swedish expert organisations within the nuclear power utilities have gradually been phased out or transformed into consulting firms. Changes have also taken place at the Swedish vendor of boiling-water plants, now Westinghouse Atom, and the activities have been down sized considerably in Sweden. There has been a similar trend in other countries. Moreover, countries which previously conducted expensive experiments have themselves increasingly sought international support as their research resources have dwindled. As a result, numerous international projects have or are planned to be started. SKI notes that Swedish nuclear activities are also becoming increasingly dependent on international collaboration. SKI further notes that in order to fulfil its assignment, the Inspectorate needs not only financial resources but also competent personnel. This enables targeted support to be maintained to strategic national infrastructure and to international cooperation including internationally financed projects. With this is meant above all experimental research where small countries such as Sweden can join forces with other countries on to important research information at
Mognoni, P; Rossi, G; Gastaldelli, F; Canclini, A; Cotelli, F
The purpose of this study was to compare heart rate responses and speed in two cross-country skiing races, which were run by seven male and seven female subjects by using classic and free style. Heart rates and skiing velocities were analyzed over flat, uphill and downhill sections, which were run from one to three times. Heart rates were higher in uphill sections than in flat sections; a steady-state heart rate was never reached in the downhill section. When the same uphill section was repeated, the heart rate tended to increase but the speed to decrease. Oxygen uptake (VO2) was calculated from heart rate:VO2 ratio, measured during uphill walking with the aid of poles. The mean (SD) energy cost of locomotion (i.e., the ratio between net VO2 and speed) was 162.1 (9.4) ml.km(-1).kg(-1) and 147.7 (7.1) ml.km(-1).kg(-1) when male subjects ran the flat section after first downhill by using classic and free style, respectively. Females had lower values for VO2 and speed, but similar energy costs. In general, the variability of the energy cost of locomotion in skiers of a similar competitive level is of the same order as that found in uphill walking on a treadmill.
Full Text Available The present paper presents, after a short history of alpine skiing which describes apparition, necessity, utility and universality of skiing during time, a comparative study referring to the alpine skiing domain in the Semenic Mountains area. In the paper are also presented general notions about alpine skiing methodology together with an ample description of the plateau area form Semenic Mountains, describing localization and touristic potential. Based on the SWOT analysis made for each slope, was realized a complex analysis of the entire skiing domain, an analysis which includes technical, financial, climatic and environmental aspects, along with an analysis of the marketing policy applied for the specific zone.
Full Text Available Background: Regular physical activity is the crucial factor in treating lifestyle diseases. The age of adolescence is considered as the important period of person's life for creation and further maintaining healthy lifestyle habits. We assume that the level of physical activities of young people could be influenced by the possibilities to perform the preferred sporting activities. Objective: The aim of the presented study was to estimate the total amount of performed physical activity and the structure of sport preferences in West Bohemian adolescents. Further to find out the existence of relationships between preferred sport branches and composition of weekly physical activities of girls and boys. Methods: The research was conducted at five selected secondary schools of the Pilsen region, under the total participation of 382 boys and 529 girls. The level of physical activity (PA and sporting preferences was assessed by means of the IPAQ questionnaire and questionnaire of sports preferences, with the use of the internet system INDARES. For the statistical processing of the gained data, the Kruskal-Wallis ANOVA test, crosstabulation tables, and Spearman correlation analysis were used. Results: The results showed that the preference of fitness activities is associated with a higher level of PA in spare time of boys (p = .006, and with intensive PA of boys (p = .014 and girls (p = .044, compared to those, who do not prefer these activities. In addition, in case of boys, we have found statistically significant correlations (p = .022 between the preference of team sports and PA at school. 51.8% of boys and 37.7% of girls, who prefer fitness activities, comply with the recommendation of at least 3 × 20 minutes of intensive PA during one week (out of those, who do not prefer, only 30.5% of boys and 18.1% of girls. Individual sports (swimming, cycling, and downhill skiing are the main physical activities preferred by
Rovida, Francesco; Schou, Casper; Andersen, Rasmus Skovgaard
During the last decades, the methods for intuitive task level programming of robots have become a fundamental point of interest for industrial application. The paper in hand presents SkiROS (Skill-based Robot Operating System) a novel software architecture based on the skills paradigm. The skill ...... of a ﬂexible, highly modular system for the development of cognitive robot tasks....
Pantelis Theodoros Nikolaidis
Full Text Available It is well known that athletes from a specific region or country are dominating certain sports disciplines such as marathon running or Ironman triathlon; however, little relevant information exists on cross-country skiing. Therefore, the aim of the present study was to investigate the aspect of region and nationality in one of the largest cross-country skiing marathons in Europe, the “Engadin Ski Marathon.” All athletes (n=197,125 who finished the “Engadin Ski Marathon” between 1998 and 2016 were considered. More than two-thirds of the finishers (72.5% in women and 69.6% in men were Swiss skiers, followed by German, Italian, and French athletes in both sexes. Most of the Swiss finishers were from Canton of Zurich (20.5%, Grisons (19.2%, and Berne (10.3%. Regarding performance, the Russians were the fastest and the British the slowest. Considering local athletes, finishers from Canton of Uri and Glarus were the fastest and those from Canton of Geneva and Basel the slowest. Based on the findings of the present study, it was concluded that local athletes were not the fastest in the “Engadin Ski Marathon.” Future studies need to investigate other cross-country skiing races in order to find the nationalities and regions of the fastest cross-country skiers.
Smartt, Pam; Chalmers, David
Injuries arising from ski-lift malfunction are rare. Most arise from skier error when embarking or disembarking, or from improper lift operation. A search of the literature failed to uncover any studies focusing specifically on ski-lift injuries. The purpose of this study was to identify and characterise ski-lift injury resulting in hospitalisation and comment on barriers to reporting and reporting omissions. New Zealand hospitalised injury discharges 2000-2005 formed the primary dataset. To aid case identification these data were linked to ACC compensated claims for the same period and the data searched for all hospitalised cases of injury arising from ski-lifts. 44 cases were identified representing 2% of snow-skiing/snowboarding cases. 28 cases (64%) were male and 16 (36%) female, the average age was 32 yrs (range 5-73 yrs). The majority of cases were snow-skiers (35 cases, 80%). Most of the injuries were serious, or potentially so, with 1 case of traumatic pneumothorax, one of pulmonary embolism (after jumping from a ski-lift) and 28 cases sustaining fractures (six to the neck-of-femur, one to the lumbar spine and one to the pubis). ICISS scores for all cases ranged from 1.00 to 0.8182 (probability of dying in hospital 0-18.18%). Only 14 (32%) cases could be easily identified from ICD-10-AM e-codes and activity codes in the discharge summary. The ICD-10-AM external cause code for ski-lift injury V98 ("other specified transport accidents") was only assigned to 39% of cases. The type of ski-lift could only be determined in 24 cases (55%). Copyright 2009 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.
Camliguney, Asiye Filiz
Skiing is a sport where balance and strength are critical and which can be practiced actively especially from early years to old age. The purpose of this study is to examine the effect of a 5-day training of skiing skills on dynamic balance performance and development of vertical jump strength in adolescents. Sixteen adolescent volunteers who do…
Nagle, Kyle B
Cross-country skiing is a low injury-risk sport that has many health benefits and few long-term health risks. Some concern exists that cross-country skiing may be associated with a higher incidence of atrial fibrillation; however, mortality rates among skiers are lower than those among the general population. While continuing to emphasize aerobic and anaerobic training, training methods also should promote ski-specific strength training to increase maximum force and its rate of delivery and to build muscular endurance to maintain that power through a race. Multiple tests are available to monitor training progress. Which tests are most appropriate depends on the specific events targeted. In addition to laboratory-based tests, there also are many simpler, more cost-effective tests, such as short time trials, that can be used to monitor training progress and predict performance particularly at the junior skier level where access and cost may be more prohibitive.
Johnson, Robert J; Ettlinger, Carl F; Shealy, Jasper E
There are many commonly discussed myths about ski safety that are propagated by industry, physicians, and skiers. Through a review of the literature concerning 12 such topics, this article demonstrates that the following are untrue: (1) Broken legs have been traded for blown-out knees. (2) If you know your DIN (a slang term for release indicator value), you can adjust your own bindings. (3) Toe and heel piece settings must be the same to function properly. (4) Formal ski instruction will make you safer. (5) Very short skis do not need release bindings. (6) Spending a lot of money on children's equipment is not worth the cost. (7) Children need plenty of room in ski boots for their growing feet. (8) If you think you are going to fall, just relax. (9) Exercise can prevent skiing injuries. (10) Lower release settings can reduce the risk of anterior cruciate ligament injury. (11) Buying new ski equipment is safer than renting. (12) Skiing is among the most dangerous of activities. It is important for the skiing public, physicians, and all those interested in improving skiing safety to verify the measures they advocate. The statements analyzed here are simply untrue and have the potential to cause harm if taken as fact by those exposed to these unsupported opinions.
Hausbrandt, D; Höllwarth, M; Ritter, G
3374 accidents occurring on the field of sport during the years 1975--1977 accounted for 19% of all accidents dealt with at the Institute of Kinderchirurgie in Graz. 51% of the accidents were caused by the typical winter sports: skiing, tobogganing, ice-skating and ski-jumping with skiing accounting for 75% of the accidents. The fracture localization typical of the different kinds of winter sport is dealt with in detail. The correct size and safety of the equipment were found to be particularly important in the prevention of such accidents in childhood.
Chidley, Joel B; MacGregor, Alexandra L; Martin, Caoimhe; Arthur, Calum A; Macdonald, Jamie H
To identify physiological, psychological, and skill characteristics that explain performance in downhill (DH) mountain-bike racing. Four studies were used to (1) identify factors potentially contributing to DH performance (using an expert focus group), (2) develop and validate a measure of rider skill (using video analysis and expert judge evaluation), (3) evaluate whether physiological, psychological, and skill variables contribute to performance at a DH competition, and (4) test the specific contribution of aerobic capacity to DH performance. STUDY 1 identified aerobic capacity, handgrip endurance, anaerobic power, rider skill, and self-confidence as potentially important for DH. In study 2 the rider-skill measure displayed good interrater reliability. Study 3 found that rider skill and handgrip endurance were significantly related to DH ride time (β=-0.76 and -0.14, respectively; R2=.73), with exploratory analyses suggesting that DH ride time may also be influenced by self-confidence and aerobic capacity. Study 4 confirmed aerobic capacity as an important variable influencing DH performance (for a DH ride, mean oxygen uptake was 49±5 mL·kg(-1)·min(-1), and 90% of the ride was completed above the 1st ventilatory threshold). In order of importance, rider skill, handgrip endurance, self-confidence, and aerobic capacity were identified as variables influencing DH performance. Practically, this study provides a novel assessment of rider skill that could be used by coaches to monitor training and identify talent. Novel intervention targets to enhance DH performance were also identified, including self-confidence and aerobic capacity.
Gomez, Andrew Thomas; Rao, Ashwin
Adventure and extreme sports often involve unpredictable and inhospitable environments, high velocities, and stunts. These activities vary widely and include sports like BASE jumping, snowboarding, kayaking, and surfing. Increasing interest and participation in adventure and extreme sports warrants understanding by clinicians to facilitate prevention, identification, and treatment of injuries unique to each sport. This article covers alpine skiing and snowboarding, skateboarding, surfing, bungee jumping, BASE jumping, and whitewater sports with emphasis on epidemiology, demographics, general injury mechanisms, specific injuries, chronic injuries, fatality data, and prevention. Overall, most injuries are related to overuse, trauma, and environmental or microbial exposure. Copyright © 2016 Elsevier Inc. All rights reserved.
The objective of the book is to review comprehensively what is known about the distribution and determinants of injury rates in a variety of individual sports, and to suggest injury prevention measures and guidelines for further research. This book provides comprehensive compilation and critical analysis of epidemiological data over children's individual sports: including equestrian, gymnastics, martial arts, skiing and snowboarding, tennis, track and field, and wrestling. This book enc...
Moxnes, John F; Sandbakk, Oyvind; Hausken, Kjell
The current study simulated cross-country skiing on varying terrain by using a power balance model. By applying the hypothetical inductive deductive method, we compared the simulated position along the track with actual skiing on snow, and calculated the theoretical effect of friction and air drag on skiing performance. As input values in the model, air drag and friction were estimated from the literature, whereas the model included relationships between heart rate, metabolic rate, and work rate based on the treadmill roller-ski testing of an elite cross-country skier. We verified this procedure by testing four models of metabolic rate against experimental data on the treadmill. The experimental data corresponded well with the simulations, with the best fit when work rate was increased on uphill and decreased on downhill terrain. The simulations predicted that skiing time increases by 3%-4% when either friction or air drag increases by 10%. In conclusion, the power balance model was found to be a useful tool for predicting how various factors influence racing performance in cross-country skiing.
Spandre, Pierre; François, Hugues; Morin, Samuel; George-Marcelpoil, Emmanuelle; Lafaysse, Matthieu
Investigations of the capacity of ski resorts to anticipate, cope with and recover from the impact of natural snow scarcity through snow management (grooming, snowmaking) have been realized in most of the major regions in terms of international ski offer although not in the French Alps hitherto. The present work therefore introduces an innovative approach for the investigation of socio economic implications of changes in snow conditions for the French Alps ski resorts based on a panel of 129 resorts representing 96% of the total French Alps ski lifts infrastructures. We integrated detailed spatial representations of ski resorts (including priority areas for snowmaking equipment) along with physically based snowpack modelling (including the physical impact of grooming and snowmaking). The viability of ski resorts was further adressed thanks to a commonly used rule based on the snow season duration at the village and ski lifts average elevations along with the development of original viability indicators of snow conditions in the French Alps ski resorts based on the specific periods for the economic success of winter sports: Christmas and February school holidays. Such indicators were correlated to the number of ski lifts tickets sales over the 2001 - 2014 period and proved to be relevant to investigate and predict the evolutions of ski lifts tickets sales under the current ski market conditions in the French Alps. Our results outlined the contrast of snow conditions between French Alps ski resorts, even when accounting for snow management, particularly regarding the geographical location of resorts (Southern versus Northern Alps), the size and related elevation range of ski resorts. Our physically based approach also allowed to compute the water and energy requirements for the production of Machine Made snow since the start of the development of snowguns in the French Alps. Our computations proved to be strongly correlated to the observed amounts of water from the
Mildner, E; Lembert, S; Raschner, C
Modern ski carving technique demands that skiers have a strong sense of balance and edge their skis with precision and feeling. Stiff ski boots facilitate the transfer of power to the ski but increase the difficulty of balancing. The aim of this study was to analyse the influence of ski boots on balance performance of alpine skiers. 76 experienced skiers (female 33/male 43) and 76 ski racers of the Skigymnasium Stams (female 31/male 45) were tested on the MFT S 3 Check with and without ski boots. Ski boots significantly influenced balance. There were also significant differences between experienced skiers and ski racers, but gender differences were minimal. In addition to general conditioning, skiers should utilise general and ski-specific balance and sensomotor training which could help in ski injury prevention, especially knee injuries. Georg Thieme Verlag KG Stuttgart, New York.
Moreland, M S
Skiing injuries in children continue to represent a significant health problem. The incidence of injuries in young teenagers remains significantly above the rate for all ages, and tibial fractures are particularly common. Continued efforts are needed to design adequate binding systems for the child that will account for the demands of a broad range of varying sizes and skill levels. As organized competition becomes more popular, there must be an increasing awareness and supervision of the unique musculoskeletal requirements of young competitors in both Alpine and Nordic events.
Stenroos, A; Pakarinen, H; Jalkanen, J; Mälkiä, T; Handolin, L
Alpine skiing and snowboarding share the hazards of accidents accounting for tibial fractures. The aim of this study was to evaluate the fracture patterns and mechanisms of injury of tibial fractures taking place in downhill skiing and snowboarding. All patients with tibial fracture due to alpine skiing or snowboarding accident treated in four trauma centers next to the largest ski resorts in Finland were analyzed between 2006 and 2012. The hospital records were retrospectively reviewed for data collection: equipment used (skis or snowboard), age, gender, and mechanism of injury. Fractures were classified according to AO-classification. There were 342 skiing and 30 snowboarding related tibial fractures in 363 patients. Tibial shaft fracture was the most common fracture among skiers (n = 215, 63%), followed by proximal tibial fractures (n = 92, 27%). Snowboarders were most likely to suffer from proximal tibial fracture (13, 43%) or tibial shaft fracture (11, 37%). Snowboarders were also more likely than skiers to suffer complex AO type C fractures (23% vs 9%, p jumping (46%). The most important finding was the relatively high number of the tibial plateau fractures among adult skiers. The fracture patterns between snowboarding and skiing were different; the most common fracture type in skiers was spiral tibial shaft fracture compared to proximal tibial fractures in snowboarders. Children had more simple fractures than adults. © The Finnish Surgical Society 2016.
Müller, Lisa; Hildebrandt, Carolin; Müller, Erich; Fink, Christian; Raschner, Christian
Alpine ski racing is known to be a sport with a high risk of injuries. Because most studies have focused mainly on top-level athletes and on traumatic injuries, limited research exists about injury risk factors among youth ski racers. The aim of this study was to determine the intrinsic risk factors (anthropometrics, biological maturity, physical fitness, racing technique) for injury among youth alpine ski racers. Study participants were 81 youth ski racers attending a ski boarding school (50 males, 31 females; 9–14 years). A prospective longitudinal cohort design was used to monitor sports-related risk factors over two seasons and traumatic (TI) and overuse injuries (OI). At the beginning of the study, anthropometric characteristics (body height, body weight, sitting height, body mass index); biological maturity [status age at peak height velocity (APHV)]; physical performance parameters related to jump coordination, maximal leg and core strength, explosive and reactive strength, balance and endurance; and ski racing technique were assessed. Z score transformations normalized the age groups. Multivariate binary logistic regression (dependent variable: injury yes/no) and multivariate linear regression analyses (dependent variable: injury severity in total days of absence from training) were calculated. T-tests and multivariate analyses of variance were used to reveal differences between injured and non-injured athletes and between injury severity groups. The level of significance was set to p jump contact time; and higher drop jump reactive strength index were at a lower injury risk or more vulnerable for fewer days of absence from training. However, significant differences between injured and non-injured athletes were only observed with respect to the drop jump reactive strength index. Regular documentation of anthropometric characteristics, biological maturity and physical fitness parameters is crucial to help to prevent injury in youth ski racing. The present
Müller, Lisa; Hildebrandt, Carolin; Müller, Erich; Fink, Christian; Raschner, Christian
Alpine ski racing is known to be a sport with a high risk of injuries. Because most studies have focused mainly on top-level athletes and on traumatic injuries, limited research exists about injury risk factors among youth ski racers. The aim of this study was to determine the intrinsic risk factors (anthropometrics, biological maturity, physical fitness, racing technique) for injury among youth alpine ski racers. Study participants were 81 youth ski racers attending a ski boarding school (50 males, 31 females; 9-14 years). A prospective longitudinal cohort design was used to monitor sports-related risk factors over two seasons and traumatic (TI) and overuse injuries (OI). At the beginning of the study, anthropometric characteristics (body height, body weight, sitting height, body mass index); biological maturity [status age at peak height velocity (APHV)]; physical performance parameters related to jump coordination, maximal leg and core strength, explosive and reactive strength, balance and endurance; and ski racing technique were assessed. Z score transformations normalized the age groups. Multivariate binary logistic regression (dependent variable: injury yes/no) and multivariate linear regression analyses (dependent variable: injury severity in total days of absence from training) were calculated. T -tests and multivariate analyses of variance were used to reveal differences between injured and non-injured athletes and between injury severity groups. The level of significance was set to p core flexion strength; smaller core flexion:extension strength ratio; shorter drop jump contact time; and higher drop jump reactive strength index were at a lower injury risk or more vulnerable for fewer days of absence from training. However, significant differences between injured and non-injured athletes were only observed with respect to the drop jump reactive strength index. Regular documentation of anthropometric characteristics, biological maturity and physical fitness
Mikkola, Jussi; Laaksonen, Marko; Holmberg, Hans-Christer; Vesterinen, Ville; Nummela, Ari
The present study investigated the performance-predicting factors of a simulated cross-country (XC) skiing sprint competition on roller skis, on a slow surface. Sixteen elite male XC skiers performed a simulated sprint competition (4 x 850 m heat with a 20-minute recovery) using V2 skating technique on an indoor tartan track. Heat velocities, oxygen consumption, and peak lactate were measured during or after the heats. Maximal skiing velocity was measured by performing a 30-m speed test. Explosive and maximal force production in the upper body was determined by bench press (BP). Subjects also performed maximal anaerobic skiing test (MAST) and the 2 x 2-km double poling (DP) test. The maximal velocity of MAST (VMAST) and velocities at 3 (V3), 5 (V5), 7 (V7) mmol.L lactate levels in MAST were determined. In the 2 x 2-km test, DP economy (VO2SUBDP) and maximal 2-km DP velocity (VDP2KM) were determined. The best single performance-predicting factors for the sprint performance were VDP2KM (r = 0.73, p < 0.01), V7 (r = 0.70, p < 0.01), and VO2SUBDP (r = -0.70, p < 0.01). Faster skiers in sprint simulation had a higher absolute VO2 (L.min) (p < 0.05-0.01) during sprint heats, and higher anaerobic skiing power (VMAST, p < 0.05) and better anaerobic skiing economy (V3, V5, V7, p < 0.05-0.001) than slower skiers. Faster skiers were also stronger in BP, with regard to both absolute (p < 0.01) and relative (p < 0.05) values. In addition, anaerobic characteristics seem to be of importance at the beginning of the XC skiing sprint competition, whereas the aerobic characteristics become more important as the XC skiing sprint competition progressed. This study indicates that sprint skiers should emphasize sport-specific upper body training, and training skiing economy at high speeds.
Hurst, Howard Thomas; Atkins, Stephen
The purpose of this study was to assess the power output of field-based downhill mountain biking. Seventeen trained male downhill cyclists (age 27.1 +/- 5.1 years) competing nationally performed two timed runs of a measured downhill course. An SRM powermeter was used to simultaneously record power, cadence, and speed. Values were sampled at 1-s intervals. Heart rates were recorded at 5-s intervals using a Polar S710 heart rate monitor. Peak and mean power output were 834 +/- 129 W and 75 +/- 26 W respectively. Mean power accounted for only 9% of peak values. Paradoxically, mean heart rate was 168 +/- 9 beats x min(-1) (89% of age-predicted maximum heart rate). Mean cadence (27 +/- 5 rev x min(-1)) was significantly related to speed (r = 0.51; P biking. The poor relationships between power and run time and between cadence and run time suggest they are not essential pre-requisites to downhill mountain biking performance and indicate the importance of riding dynamics to overall performance.
Bolger, Conor M; Kocbach, Jan; Hegge, Ann Magdalen; Sandbakk, Øyvind
To compare the speed and heart-rate profiles during international skating and classical competitions in male and female world-class cross-country skiers. Four male and 5 female skiers performed individual time trials of 15 km (men) and 10 km (women) in the skating and classical techniques on 2 consecutive days. Races were performed on the same 5-km course. The course was mapped with GPS and a barometer to provide a valid course and elevation profile. Time, speed, and heart rate were determined for uphill, flat, and downhill terrains throughout the entire competition by wearing a GPS and a heart-rate monitor. Times in uphill, flat, and downhill terrain were ~55%, 15-20%, and 25-30%, respectively, of the total race time for both techniques and genders. The average speed differences between skating and classical skiing were 9% and 11% for men and women, respectively, and these values were 12% and 15% for uphill, 8% and 13% for flat (all P skating and classical, respectively, with corresponding numbers of 11% and 14% for uphill, 6% and 11% for flat, and 4% and 5% for downhill terrain (all P skating and classical techniques and between the 2 genders were found on uphill terrain. Therefore, these speed differences could not be explained by variations in exercise intensity.
MSc Lotte Salome; Drs. Maarten van Bottenburg
During the last twenty years, a remarkable new type of service has been developed in the world of sports, which can be described as the indoorisation of outdoor sports. Typical outdoor sports like climbing, skiing, surfing, rowing, and skydiving, which used to be exclusively practiced in a natural
van Bottenburg, M.; Salome, L.
During the last 20 years, a remarkable new type of service has been developed in the world of sports, which can be described as the indoorisation of outdoor sports. Typical outdoor sports like climbing, skiing, surfing, rowing and skydiving, which used to be exclusively practised in a natural
Haselbacher, Matthias; Mader, Katharina; Werner, Maximiliane; Nogler, Michael
Ski mountaineering is becoming a popular sport. The ascending techniques (tracks) can be divided into 3 different groups: flat field, direct ascent, and traversing. This study examines the relationship between different mechanical loads on the foot and the 4 different mountaineering ascending techniques. All subjects used the same pair of ski boots and the same skis while performing the 4 different ascending techniques. An in-shoe dynamic pressure measuring system was used to measure the mechanical load on the foot soles of each ski mountaineer. The foot sole was divided into 6 anatomic sections to measure the different loads in each section. Thirteen men with an average age of 29 years were enrolled in the study. The results showed small, not significant differences in the mechanical foot load in the flat field or in the direct ascent. The average mechanical foot load was highest on the valley side foot while traversing (179 kPa to 117 kPa). The higher load forces were in the medial ball of the foot and the longitudinal aspect of the foot side closer to the hill. The higher impact placed on the valley side foot and the concentration of force placed on the medial ball of the valley side foot suggested the influence of the track on the load pattern of the foot sole. This higher impact may result in upward forces that affect the force distribution in the ankle and knee joints. Copyright © 2014. Published by Elsevier Inc.
McBeth, Paul B; Ball, Chad G; Mulloy, Robert H; Kirkpatrick, Andrew W
Alpine skiing and snowboarding are popular winter sports in Canada. Every year participation in these activities results in traumatic injury. The purpose of this study was to identify the incidence and injury patterns, as well as risk factors associated with ski and snowboarding injuries. A comprehensive 10-year retrospective review of Alpine ski and snowboarding injuries from 1996 to 2006 was conducted. The Alberta Trauma Registry was used as the primary source of data. A total of 196 patients (56.6% skiers, 43.4% snowboarders) were identified as having major traumatic injuries (Injury Severity Score, >or=12). Forty-three patients required intensive care unit support. The majority of injuries were related to falls and collisions with natural objects. Head injuries were most common, followed by chest, spinal, and extremity trauma. Seventy-nine patients required emergency surgery. Skiing and snowboarding represent activities with high potential for traumatic injury. Safety initiatives should be developed to target this population.
Suckert, K; Benedetto, K P; Vogel, A
This is an analysis of decline of rupture of the Achilles tendon in skiing while there is a steady increase of skiing injuries. Three groups, equipped with three different types of ski boots were observed once on a plane slope on the other hand on a bump track. The simultaneous size of angle of knee and ankle was measured by telemetry. The high plastic ski boot, which obstructs the ankle forward and lateral is apart from the rise of heel in the boot, the safety binding and the new skiing style the main reason for decline of rupture of the Achilles tendon in skiing.
Material and Methods: This research was conducted using data that were recorded in the Erciyes Ski Centre Injury Surveillance System from 2012 to 2016 by ski patrols. We calculated the number of skiers from sold lift cards and tickets. A total of 616 cases of skiing injuries were recorded over the four seasons. Results: The calculated injury rate was 2.6 per 1000 skiers in the period of 2012-2016. A total of 372 (60.4% patients were males and 244 were (39.6% females and their mean ages were 27.2 ± 9.8 (range 7-65 years. The most common mechanisms of injuries were falling (82.3 followed by collision (11.5%. Skiing injuries occurred mostly at the lower extremities (52.6%, followed by upper extremities (20.4%.The most frequently seen cases were contusions (59.7% and sprains (12.5%. Conclusion: The rate of injury was compatible with reference ranges (2-4‰ for Erciyes Ski Centre during all seasons. Injuries were seen mostly in adults. The most frequent injuries were at the lower extremities, which were falling-related and contusions. There were no substantial proportional changes in terms of the variables between the seasons.
... land management plan. Since SAROEA provides that snow sports must remain paramount at ski areas on NFS... Winter Sports Program Manager, 707-562-8842. Individuals who use telecommunication devices for the deaf...., Eastern Daylight Time, Monday through Friday. SUPPLEMENTARY INFORMATION: 1. Background and Need for the...
Full Text Available After falls, skiers or snowboarders often slide on the slope and may collide with obstacles. Thus, the skier’s friction on snow is an important factor to reduce incidence and severity of impact injuries. The purpose of this study was to measure snow friction of different fabrics of ski garments with respect to roughness, speed, and contact pressure. Three types of fabrics were investigated: a commercially available ski overall, a smooth downhill racing suit, and a dimpled downhill racing suit. Friction was measured for fabrics taped on a short ski using a linear tribometer. The fabrics’ roughness was determined by focus variation microscopy. Friction coefficients were between 0.19 and 0.48. Roughness, friction coefficient, and friction force were highest for the dimpled race suit. The friction force of the fabrics was higher for the higher contact pressure than for the lower one at all speeds. It was concluded that the main friction mechanism for the fabrics was dry friction. Only the fabric with the roughest surface showed friction coefficients, which were high enough to sufficiently decelerate a sliding skier on beginner and intermediate slopes.
Full Text Available The aim of this paper is focused on the problem of improving movement notion and increasing the efficiency of motor learning in skiing using multimedia tools. The text approaches the system providing a targeted feedback in the process of the acquisition of skiing skills. The platform influencing the movement notion introduces innovative means of the acquisition of essential skiing skills in ski courses organized by the Department of PE and Sport of the Faculty of Education, University of Hradec Králové. The paper presents the selected results of the survey realized by an enquiring method, which was aimed to find out opinions on a monitored platform among students specializing in physical education and sport, who took part in this form of education. The research results indicate that the use of multimedia tools in providing visual feedback can effectively influence the process and the final effect of the acquisition of skiing skills. Positive opinions of the overwhelming majority of respondents illustrate that the use of video analysis in combination with verbal mistake correction is an effective support in skiing practice and it is an efficient platform that accelerates results in learning skiing technique, especially in the context of educational courses. Conclusions also point to some of the negative aspects related to the use of multimedia tools within the platform.
... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Water skiing. 27.33 Section 27.33 Wildlife... NATIONAL WILDLIFE REFUGE SYSTEM PROHIBITED ACTS Disturbing Violations: With Vehicles § 27.33 Water skiing. When water skiing is permitted upon national wildlife refuge waters, the public will be notified under...
Müller, W; Gröschl, W; Müller, R; Sudi, K
Underweight is becoming increasingly prevalent in many sports. Among world class ski jumpers, the body mass index BMI has decreased by 4 units since 1970. The BMI ignores different body properties of individuals. Particular care should be taken in groups with unusual leg length to avoid classifying them inappropriately as thin or overweight (WHO). The improved measure MI (mass index) for relative body weight overcomes this shortcoming. Anthropometric data of ski jumpers was collected during the Olympic Games in Salt Lake City (2002; participation 81 %, n = 57), during the Summer Grand Prix in Hinterzarten (2000; participation 100 %, n = 92), and during the World Cup in Planica (2000; n = 56). The BMI and the MI were determined. The MI considers the individual leg length: A person with longer legs than average has an MI > BMI, and vice versa: MI = 0.28 m/s2 (m: mass in kg, s: sitting height in meters). BMI classes of ski jumpers in the season 2004/2005 were calculated from their official individual ski length limitation which is a function of their BMI. BMI means were 19.84 in Planica, 19.58 in Hinterzarten, and 19.43 kg m(-2) in SLC. Lowest BMI was 16.4 kg m(-2). The percentage of underweight ski jumpers (BMI ski jumping regulations. The ratio s/h = C (s = sitting height, h = height, C = cormic index) ranged from 0.49 to 0.57. Accordingly, the MI values (which are leg length corrected BMI values according to MI = BMI (C /C) (k) with k = 2 and C = 0.53) deviated remarkably from BMI values. For the 49 cases with BMI or MI or both below 18.5 kg m(-2), the classification to be underweight or not changed in 69 % when the MI was used instead of the BMI. Underweight or overweight is not only a question of cut-off points; the measure used determines the classification accuracy. A substantial improvement of weight analyses in sports medicine, public health, and general medicine as well can be obtained by using the MI instead of the BMI.
Moxnes, John F; Sandbakk, Oyvind; Hausken, Kjell
The current study adapts the power balance model to simulate cross-country skiing on varying terrain. We assumed that the skier's locomotive power at a self-chosen pace is a function of speed, which is impacted by friction, incline, air drag, and mass. An elite male skier's position along the track during ski skating was simulated and compared with his experimental data. As input values in the model, air drag and friction were estimated from the literature based on the skier's mass, snow conditions, and speed. We regard the fit as good, since the difference in racing time between simulations and measurements was 2 seconds of the 815 seconds racing time, with acceptable fit both in uphill and downhill terrain. Using this model, we estimated the influence of changes in various factors such as air drag, friction, and body mass on performance. In conclusion, the power balance model with locomotive power as a function of speed was found to be a valid tool for analyzing performance in cross-country skiing.
Simkin, Mark G.
Most commercial programming applications are considerably more complex than the end-of-chapter exercises found in programming textbooks. This case addresses this problem by requiring the students in entry-level Visual Basic programming classes to create an application that helps users order ski equipment from a retailer. For convenience, the forms…
Balzarini, R.; Dalmasso, A.; Murat, M.
This article presents preliminary results from a research project in progress that brings together geographers, cognitive scientists, historians and computer scientists. The project investigates the evolution of a particular territorial model: ski trails maps. Ski resorts, tourist and sporting innovations for mountain economies since the 1930s, have needed cartographic representations corresponding to new practices of the space.Painter artists have been involved in producing ski maps with painting techniques and panoramic views, which are by far the most common type of map, because they allow the resorts to look impressive to potential visitors. These techniques have evolved throughout the mutations of the ski resorts. Paper ski maps no longer meet the needs of a large part of the customers; the question now arises of their adaptation to digital media. In a computerized process perspective, the early stage of the project aims to identify the artist-representations, based on conceptual and technical rules, which are handled by users-skiers to perform a task (location, wayfinding, decision-making) and can be transferred to a computer system. This article presents the experimental phase that analyzes artist and user mental representations that are at stake during the making and the reading of a paper ski map. It particularly focuses on how the invention of the artist influences map reading.
Full Text Available This article presents preliminary results from a research project in progress that brings together geographers, cognitive scientists, historians and computer scientists. The project investigates the evolution of a particular territorial model: ski trails maps. Ski resorts, tourist and sporting innovations for mountain economies since the 1930s, have needed cartographic representations corresponding to new practices of the space.Painter artists have been involved in producing ski maps with painting techniques and panoramic views, which are by far the most common type of map, because they allow the resorts to look impressive to potential visitors. These techniques have evolved throughout the mutations of the ski resorts. Paper ski maps no longer meet the needs of a large part of the customers; the question now arises of their adaptation to digital media. In a computerized process perspective, the early stage of the project aims to identify the artist-representations, based on conceptual and technical rules, which are handled by users-skiers to perform a task (location, wayfinding, decision-making and can be transferred to a computer system. This article presents the experimental phase that analyzes artist and user mental representations that are at stake during the making and the reading of a paper ski map. It particularly focuses on how the invention of the artist influences map reading.
Sandbakk, Øyvind; Holmberg, Hans-Christer
Cross-country (XC) skiing has been an Olympic event since the first Winter Games in Chamonix, France, in 1924. Due to more effective training and tremendous improvements in equipment and track preparation, the speed of Olympic XC-ski races has increased more than that of any other Olympic endurance sport. Moreover, pursuit, mass-start, and sprint races have been introduced. Indeed, 10 of the 12 current Olympic competitions in XC skiing involve mass starts, in which tactics play a major role and the outcome is often decided in the final sprint. Accordingly, reappraisal of the success factors for performance in this context is required. The very high aerobic capacity (VO2max) of many of today's world-class skiers is similar that of their predecessors. At the same time, the new events provide more opportunities to profit from anaerobic capacity, upper-body power, high-speed techniques, and "tactical flexibility." The wide range of speeds and slopes involved in XC skiing requires skiers to continuously alternate between and adapt different subtechniques during a race. This technical complexity places a premium on efficiency. The relative amounts of endurance training performed at different levels of intensity have remained essentially constant during the past 4 decades. However, in preparation for the Sochi Olympics in 2014, XC skiers are performing more endurance training on roller skis on competition-specific terrain, placing greater focus on upper-body power and more systematically performing strength training and skiing at high speeds than previously.
Cheli, Federico; Maldifassi, Stefano; Melzi, Stefano; Sabbioni, Edoardo
The Engineering Approach to Winter Sports presents the state-of-the-art research in the field of winter sports in a harmonized and comprehensive way for a diverse audience of engineers, equipment and facilities designers, and materials scientists. The book examines the physics and chemistry of snow and ice with particular focus on the interaction (friction) between sports equipment and snow/ice, how it is influenced by environmental factors, such as temperature and pressure, as well as by contaminants and how it can be modified through the use of ski waxes or the microtextures of blades or ski soles. The authors also cover, in turn, the different disciplines in winter sports: skiing (both alpine and cross country), skating and jumping, bob sledding and skeleton, hockey and curling, with attention given to both equipment design and on the simulation of gesture and track optimization.
Full Text Available This review article reports the recent advances in the study, design and production of ski-boots for alpine skiing. An overview of the different designs and the materials used in ski-boot construction is provided giving particular emphasis to the effect of these parameters on the final performances and on the prevention of injuries. The use of specific materials for ski-boots dedicated to different disciplines (race skiing, mogul skiing, ski-mountaineering etc. has been correlated with the chemical and physical properties of the polymeric materials employed. A review of the scientific literature and the most interesting patents is also presented, correlating the results reported with the performances and industrial production of ski-boots. Suggestions for new studies and the use of advanced materials are also provided. A final section dedicated to the standards involved in ski-boot design completes this review article.
Jordan, Matthew J; Aagaard, Per; Herzog, Walter
The purpose of the present review was to: 1) provide an overview of the current understanding on the epidemiology, etiology, risk factors, and prevention methods for anterior cruciate ligament (ACL) injury in alpine ski racing; and 2) provide an overview of what is known pertaining to ACL reinjury and return to sport after ACL injury in alpine ski racing. Given that most of the scientific studies on ACL injuries in alpine ski racing have been descriptive, and that very few studies contributed higher level scientific evidence, a nonsystematic narrative review was employed. Three scholarly databases were searched for articles on ACL injury or knee injury in alpine ski racing. Studies were classified according to their relevance in relation to epidemiology, etiology, risk factors, and return to sport/reinjury prevention. Alpine ski racers (skiers) were found to be at high risk for knee injuries, and ACL tears were the most frequent diagnosis. Three primary ACL injury mechanism were identified that involved tibial internal rotation and anteriorly directed shear forces from ski equipment and the environment. While trunk muscle strength imbalance and genetics were found to be predictive of ACL injuries in development-level skiers, there was limited scientific data on ACL injury risk factors among elite skiers. Based on expert opinion, research on injury risk factors should focus on equipment design, course settings/speed, and athlete factors (eg, fitness). While skiers seem to make a successful recovery following ACL injury, there may be persistent neuromuscular deficits. Future research efforts should be directed toward prospective studies on ACL injury/reinjury prevention in both male and female skiers and toward the effects of knee injury on long-term health outcomes, such as the early development of osteoarthritis. International collaborations may be necessary to generate sufficient statistical power for ACL injury/reinjury prevention research in alpine ski racing
Full Text Available With the aim of forming an expert model of the most important operators for basic ski turn teaching in ski schools, an experiment was conducted on a sample of 20 ski experts from different countries (Croatia, Bosnia and Herzegovina and Slovenia. From the group of the most commonly used operators for teaching basic ski turn the experts picked the 6 most important: uphill turn and jumping into snowplough, basic turn with hand sideways, basic turn with clapping, ski poles in front, ski poles on neck, uphill turn with active ski guiding. Afterwards, ranking and selection of the most efficient operators was carried out. Due to the set aim of research, a Chi square test was used, as well as the differences between frequencies of chosen operators, differences between values of the most important operators and differences between experts due to their nationality. Statistically significant differences were noticed between frequencies of chosen operators (c2= 24.61; p=0.01, while differences between values of the most important operators were not obvious (c2= 1.94; p=0.91. Meanwhile, the differences between experts concerning thier nationality were only noticeable in the expert evaluation of ski poles on neck operator (c2=7.83; p=0.02. Results of current research are reflected in obtaining useful information about methodological priciples of learning basic ski turn organization in ski schools.
Le Docteur Guenin, lui-même un grand sportif, qui exerce entre beaucoup d'autres activités la course à pieds et le ski de fond, est aussi sécrétaire médical du journal "Vie et Santé. Il nous parle de l'exercice du sport, gym aérobic, jogging etc. avec présention de quelques dias et d'un film du Dr.Kupper.
Full Text Available Ski Mountaineering (SkiMo is a fast growing sport requiring both endurance and technical skills. It involves different types of locomotion with and without the skis. The aim of this study is to develop and validate in the snowfield a novel inertial-based system for analysing cycle parameters and classifying movement in SkiMo in real-time. The study was divided into two parts, one focused on real-time parameters estimation (cadence, distance from strides, stride duration, stride length, number of strides, slope gradient, and power and, second, on transition detection (kickturns, skin on, skin off, ski on and off backpack in order to classify between the different types of locomotion. Experimental protocol involved 16 experienced subjects who performed different SkiMo trials with their own equipment instrumented with a ski-mounted inertial sensor. The results obtained by the algorithm showed precise results with a relative error near 5% on all parameters. The developed system can, therefore, be used by skiers to obtain quantitative training data analysis and real-time feedback in the field. Nevertheless, a deeper validation of this algorithm might be necessary in order to confirm the accuracy on a wider population of subjects with various skill levels.
Ski injuries depend from many factors which involve the skier and his behavior, the environment, especially the weather and slopes conditions, but first of all, the typical equipment, skis, boots and bindings. These materials have undergone a great technical improvement in recent years which allowed a significant decrease of ski injuries, first of all of the typical lower leg fracture, the so called "boot fracture". Nevertheless alpine skiers are exposed to conditions not encountered in other sports. The ski and the stiff plastic ski boot combine to form an extension to the human anatomy, which subjects the lower extremities to loads not normally encountered in other activities. The velocity of the skier combine with the equipment used to expose to a risk of injury that by type, severity and incidence is unusual. The more frequent ski injury in the last 15 years involve the knee and his ligaments. These lesions often involve the medial and lateral compartment and the anterior cruciate ligament (ACL, more than 65% of all knee lesions) and the etiology is related to both the boot and bindings characteristics. Many studies have shown the direct relationship between injuries of the lower extremity and equipment (the so called LEER-injuries, near 46% of all lesions in US studies) and also the importance of a proper binding setting for a lower risk. Ski boots are indicated as the primary cause of the ACL tears but, at this moment, for this lesion 4 mechanisms are described.(ABSTRACT TRUNCATED AT 250 WORDS)
Full Text Available Alpine ski racing is known to be a sport with a high risk of injuries. Because most studies have focused mainly on top-level athletes and on traumatic injuries, limited research exists about injury risk factors among youth ski racers. The aim of this study was to determine the intrinsic risk factors (anthropometrics, biological maturity, physical fitness, racing technique for injury among youth alpine ski racers. Study participants were 81 youth ski racers attending a ski boarding school (50 males, 31 females; 9–14 years. A prospective longitudinal cohort design was used to monitor sports-related risk factors over two seasons and traumatic (TI and overuse injuries (OI. At the beginning of the study, anthropometric characteristics (body height, body weight, sitting height, body mass index; biological maturity [status age at peak height velocity (APHV]; physical performance parameters related to jump coordination, maximal leg and core strength, explosive and reactive strength, balance and endurance; and ski racing technique were assessed. Z score transformations normalized the age groups. Multivariate binary logistic regression (dependent variable: injury yes/no and multivariate linear regression analyses (dependent variable: injury severity in total days of absence from training were calculated. T-tests and multivariate analyses of variance were used to reveal differences between injured and non-injured athletes and between injury severity groups. The level of significance was set to p < 0.05. Relatively low rates of injuries were reported for both traumatic (0.63 TI/athlete and overuse injuries (0.21 OI/athlete. Athletes with higher body weight, body height, and sitting height; lower APHV values; better core flexion strength; smaller core flexion:extension strength ratio; shorter drop jump contact time; and higher drop jump reactive strength index were at a lower injury risk or more vulnerable for fewer days of absence from training. However
Full Text Available In spite of the wide range of injuries in adolescents during sports activities, there are only a few studies investigating the type and frequency of sport injuries in puberty. However, this information may help to prevent, diagnose and treat sports injuries among teens. 4468 injuries in adolescent patients were treated over a ten year period of time: 66,97% were boys and 32.88% girls. The most frequent sports injuries were football (31.13% followed by handball (8.89% and sports during school (8.77%. The lower extremity was involved in 68.71% of the cases. Knee problems were seen in 29.79% of the patients; 2.57% spine and 1.99% head injuries. Injuries consisted primarily of distortions (35.34% and ligament tears (18.76%; 9,00% of all injuries were fractures. We found more skin wounds (6:1 and fractures (7:2 in male patients compared to females. The risk of ligament tears was highest during skiing. Three of four ski injuries led to knee problems. Spine injuries were observed most often during horse riding (1:6. Head injuries were seen in bicycle accidents (1:3. Head injuries were seen in male patients much more often then in female patients (21:1. Fractures were noted during football (1:9, skiing (1:9, inline (2:3, and during school sports (1:11. Many adolescents participate in various sports. Notwithstanding the methodological problems with epidemiological data, there is no doubt about the large number of athletes sustain musculoskeletal injuries, sometimes serious. In most instances, the accident does not happened during professional sports and training. Therefore, school teachers and low league trainer play an important role preventing further accidence based on knowledge of individual risk patterns of different sports. It is imperative to provide preventive medical check-ups, to monitor the sport-specific needs for each individual sports, to observe the training skills as well as physical fitness needed and to evaluation coaches education.
Kallinen, M; Markku, A
Illness and aging both cause many structural and functional alterations in the human body, rendering elderly people liable to overloading of the musculoskeletal and cardiovascular systems. It should, however, be kept in mind that immobilisation and inactivity have even more deleterious effects on structures and functions in the elderly than in younger adults. Most physically active elderly people are selected individuals with respect to their superior health and physical capacity compared with inactive persons of the same age, thus making it possible to further improve their physical capacity. They will, however, be affected by some of the drawbacks of physical overloading, mostly due to the diminished ability of aging body systems to adapt to high levels of loading. The safety margin of an exercise dose tends to decline with aging. Exertional injuries are common among the elderly, and are connected mostly with degenerative aging processes. Acute injuries are common in those elderly people participating in sport activities which demand high coordination, reaction time, and balance capabilities, such as ball games, down-hill skiing, and gymnastics. Muscle has been reported to be the most commonly acutely injured tissue among active elderly athletes. The lower extremities are the most susceptible to injury. A large proportion of injuries (acute and exertional) are mild and can be treated by brief cessation of training and competition activities. Some of the injuries are, however, long term and cause disability not only during training and competition, but also in the normal activities of daily living. It is important that these injuries are treated as soon as possible and in the most effective way, similarly to injuries suffered by younger people. In treating elderly people, it is most important to avoid the detrimental effects of immobilisation; this requires active treatment and rehabilitation with compensatory exercise therapy. The best 'treatment' for sports
The present research focuses on the interaction of supply and demand of down-hill ski tourism in the province of Alberta. The main hypothesis is that the demand for skiing depends on the socio-economic and demographic characteristics of the population living in the province and outside it. A second, consequent hypothesis is that the development of ski resorts (supply) is a response to the demand for skiing. From the latter derives the hypothesis of a dynamic interaction between supply (ski resorts) and demand (skiers). Such interaction occurs in space, within a range determined by physical distance and the means available to overcome it. The above hypotheses implicitly define interactions that take place in space and evolve over time. The hypotheses are tested by temporal, spatial, and spatio-temporal regression models, using the best available data and the latest commercially available software. The main purpose of this research is to explore analytical techniques to model spatial, temporal, and spatio-temporal dynamics in the context of regional science. The completion of the present research has produced more significant contributions than was originally expected. Many of the unexpected contributions resulted from theoretical and applied needs arising from the application of spatial regression models. Spatial regression models are a new and largely under-applied technique. The models are fairly complex and a considerable amount of preparatory work is needed, prior to their specification and estimation. Most of this work is specific to the field of application. The originality of the solutions devised is increased by the lack of applications in the field of tourism. The scarcity of applications in other fields adds to their value for other applications. The estimation of spatio-temporal models has been only partially attained in the present research. This apparent limitation is due to the novelty and complexity of the analytical methods applied. This opens new
Full Text Available Matthew J Jordan,1 Per Aagaard,2 Walter Herzog1 1Human Performance Laboratory, The University of Calgary, Calgary, AB, Canada; 2Department of Sports Science and Clinical Biomechanics, SDU Muscle Research Cluster (SMRC, University of Southern Denmark, Odense M, Denmark Abstract: The purpose of the present review was to: 1 provide an overview of the current understanding on the epidemiology, etiology, risk factors, and prevention methods for anterior cruciate ligament (ACL injury in alpine ski racing; and 2 provide an overview of what is known pertaining to ACL reinjury and return to sport after ACL injury in alpine ski racing. Given that most of the scientific studies on ACL injuries in alpine ski racing have been descriptive, and that very few studies contributed higher level scientific evidence, a nonsystematic narrative review was employed. Three scholarly databases were searched for articles on ACL injury or knee injury in alpine ski racing. Studies were classified according to their relevance in relation to epidemiology, etiology, risk factors, and return to sport/reinjury prevention. Alpine ski racers (skiers were found to be at high risk for knee injuries, and ACL tears were the most frequent diagnosis. Three primary ACL injury mechanism were identified that involved tibial internal rotation and anteriorly directed shear forces from ski equipment and the environment. While trunk muscle strength imbalance and genetics were found to be predictive of ACL injuries in development-level skiers, there was limited scientific data on ACL injury risk factors among elite skiers. Based on expert opinion, research on injury risk factors should focus on equipment design, course settings/speed, and athlete factors (eg, fitness. While skiers seem to make a successful recovery following ACL injury, there may be persistent neuromuscular deficits. Future research efforts should be directed toward prospective studies on ACL injury/reinjury prevention in both
Full Text Available The aim of the present research was the physical abilities diagnosis of Alpine skiing skiers and tennis players, as well the comparison of these before and after the ski period. The sample of 54 individuals emanated from two teams of different sports: skiing (N = 28 and tennis (N = 26, while the level was advancing for both. For the diagnosis and the comparison of physical abilities used four tests of Alpine skiing on dry ground the same day of December 2008 and April 2009 respectively: 30m flight start, eight continuous jumping, slalom on "folder", jumping up and down on a step with height 40cm x 40sec. The statistical analysis done with SPSS 18 program, included controls t - test, p=bilateral, for dependent samples and correlation analysis at significance level a= 0.05 with freedom degrees df = N - 1. In conclusion, in the present research the ski team (men and women presented the improvement afterwards the season in 2 of 4 tests and in the corresponding physical abilities (explosive force, t = 2,970, p < .01 and agility t = 3.533, p < .00, while also the tennis team (men and women presented improvement in 2 of 4 tests (explosive force, t = 2,397, p < .02 and anaerobic ability, t = 3.192, p < .00. Finally the common characteristic of the two teams was the performance improvement in the explosive force and their decreased attribution in speed.
Pauli, Carole A; Keller, Melanie; Ammann, Fabian; Hübner, Klaus; Lindorfer, Julia; Taylor, William R; Lorenzetti, Silvio
Squats, drop jumps, and imitation jumps are commonly used training exercises in ski jumping to enhance maximum force, explosive force, and sport-specific skills. The purpose of this study was to evaluate the kinetics and kinematics of training exercises in ski jumping and to find objective parameters in training exercises that most correlate with the competition performance of ski jumpers. To this end, barbell squats, drop jumps, and imitation jumps were measured in a laboratory environment for 10 elite ski jumpers. Force and motion data were captured, and the influence of maximum vertical force, force difference, vertical take-off velocity, knee moments, knee joint power, and a knee valgus/varus index was evaluated and correlated with their season jump performance. The results indicate that, especially for the imitation jumps, a good correlation exists between the vertical take-off velocity and the personal jump performance on the hill (R = 0.718). Importantly, however, the more the athletes tended toward a valgus knee alignment during the measured movements, the worse their performance (R = 0.729 imitation jumps; R = 0.685 squats). Although an evaluation of the athletes' lower limb alignment during competitive jumping on the hill is still required, these preliminary data suggest that performance training should additionally concentrate on improving knee alignment to increase ski jumping performance.
Full Text Available The objective of the study was to investigate the frequency of participation in sport activity of Slovenes. The sample consisted of 1286 persons, 54% were women and 46% were men. To obtain the necessary data a questionnaire method was used. We focused on two groups of questions. The first group reffered to participation in sport activity in general (frequency of any sport activity and the second group reffered to participation in a particular sport. The results show that 33% of Slovenes were regularly active, 31% occasionally active and 36% non-active. They were the most active in the following sport activities: walking, swimming, cycling, alpine skiing and mountaineering.
Full Text Available Mountain tourism potential is complex and varied in structure, size and spatial distribution, which is related to massive expansion, differentiation altitude, geological composition, configuration and specific geological landforms, fragmentation, vegetation cover and peculiarities of the river system, etc. Therefore under the mountain in northern Oltenia highlights some differences in the regions in terms of structure, volume, value, capitalizing on opportunities in tourism mountain tourism potential. Mountain tourism is one of the traditional forms of tourism in affirming Romanian tourism internationally, both through natural potential available by the low level of degradation of landscapes and through investment efforts that were made in the specific offer. European alpine countries (France, Switzerland, Austria, Italy, etc. attaches great importance to the potential of mountain tourism available and submitted in this regard, special efforts for the development of mountain resorts attract millions of tourists annually amateur ski of sports winter mountain in general. Romania has a great value ski area that can compete successfully with the ski areas of central and Western Europe. What are the strengths and weaknesses of Romanian mountain tourism potential in comparability with famous country ski area for winter sports will see throughout this paper.
Among approximately 2,600 licensed Norwegian ski jumpers, only three injuries that caused a permanent medical disability of at least 10% were incurred during the 5 year period from 1982 through 1986. When compared to the previous 5 year period (1977 to 1981), a dramatic improvement in safety is seen, as both number and severity of such injuries were markedly reduced. There are several probable reasons for this improved safety record: better preparation of the jumps, the return to using only one standard heel block, and the fact that coaches are being more responsible, especially with younger jumpers.
Spandre, Pierre; Francois, Hugues; George-Marcelpoil, Emmanuelle; Morin, Samuel
Winter tourism plays a fundamental role in the economy of French mountain regions but also in other countries such as Austria, USA or Canada. Ski operators originally developed grooming methods to provide comfortable and safe skiing conditions. The interannual variability of snow conditions and the competition with international destinations and alternative tourism activities encouraged ski resorts to mitigate their dependency to weather conditions through snowmaking facilities. However some regions may not be able to produce machine made snow due to inadequate conditions and low altitude resorts are still negatively impacted by low snow seasons. In the meantime, even though the operations of high altitude resorts do not show any dependency to the snow conditions they invest in snowmaking facilities. Such developments of snowmaking facilities may be related to a confused and contradictory perception of climate change resulting in individualistic evolutions of snowmaking facilities, also depending on ski resorts main features such as their altitude and size. Concurrently with the expansion of snowmaking facilities, a large range of indicators have been used to discuss the vulnerability of ski resorts such as the so-called "100 days rule" which was widely used with specific thresholds (i.e. minimum snow depth, dates) and constraints (i.e. snowmaking capacity). The present study aims to provide a detailed description of snow management practices and major priorities in French ski resorts with respect to their characteristics. We set up a survey in autumn 2014, collecting data from 56 French ski operators. We identify the priorities of ski operators and describe their snowmaking and grooming practices and facilities. The operators also provided their perception of the ski resort vulnerability to snow and economic challenges which we could compare with the actual snow conditions and ski lift tickets sales during the period from 2001 to 2012.
Bürkner, A; Simmen, H P
Though the injury patterns of the lower extremities in skiing have changed since 1970, tibial fractures remain daily work of hospitals near ski slopes. A lot of medical studies have analysed the relevance of well adjusted bindings of the common lesions of the knee joint ligaments. However the influence of the flexibility of the ski boot and the injury pattern has been neglected. 49 tibial fractures have been analysed in a hospital near a large ski resort in the alpes. All fractures occurred during alpine skiing. The type of the fracture, according to the AO-classification and the injury pattern have been documented. Also demographic data, ski experience and specification concerning the ski boot have been questioned. The type of the ski boot and the grade of flexibility, have been documented if possible. It has also been recorded whether the binding opened. In contrast to other studies our patients are represented in widely spread age-groups with a large share of elderly and experienced persons. Young or unexperienced sportsmen suffer primarily from fractures of the tibial diaphysis. With increasing skiing experience the injury pattern is widening on the whole leg. 62 % of all fractures are caused by rotation traumas. Compression, dorsal forces and direct collisions are the other causes. In 59 % of all accidents the binding failed to open. There is an increased risk of complex fractures in the proximal or distal epiphysis if the binding has not opened. 23 % of all fractures occurred with rented ski boots. Only 16 % of all ski boots are labelled with a flexibility index. There is no standardized value for the flexibility of ski boots. The trend can be derived that rigid ski boots with a high flexibility index cause above all fractures of the diaphysis. 10 % of all fractures happened to patients wearing "snowblades". These short skis without safety bindings contributed a considerable share to tibial fractures, even though there is no big leverage. Tibial fractures are
Andersen, W; Loland, S
With the campaign for women's participation in international and Olympic ski jumping as a practical case, sport's potential for recognition of individual rights is explored. In line with Honneth's influential ethical theory, recognition of rights refers to a mutual recognition between persons of each other as rational and responsible agents with an equal right to take part in the public formation and development of their community or practice. The argument is that women ski jumpers were entitled to compete as they had actual and/or potential capabilities and skills to contribute in the public formation and development of their sport. Their exclusion was a violation of individual rights. At a more general level, sport is discussed as a sphere for recognition of rights. It is argued that the basic principles of equal opportunity to take part and to perform make sport a particularly clear and potent sphere for such recognition, and also for the identification of rights violations. In sport, rights, or the violation of rights, are demonstrated in concrete and embodied ways. It is concluded that struggles for recognition and individual rights are a continuous process in sport as in most other human institutions and practices. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Loudin, Michael; Anderson, Sharon; Schlansky, Barry
Proximal or 'downhill' esophageal varices are a rare cause of upper gastrointestinal hemorrhage. Unlike the much more common distal esophageal varices, which are most commonly a result of portal hypertension, downhill esophageal varices result from vascular obstruction of the superior vena cava (SVC). While SVC obstruction is most commonly secondary to malignant causes, our review of the literature suggests that benign causes of SVC obstruction are the most common cause actual bleeding from downhill varices. Given the alternative pathophysiology of downhill varices, they require a unique approach to management. Variceal band ligation may be used to temporize acute variceal bleeding, and should be applied on the proximal end of the varix. Relief of the underlying SVC obstruction is the cornerstone of definitive treatment of downhill varices. A young woman with a benign superior vena cava stenosis due to a tunneled internal jugular vein dialysis catheter presented with hematemesis and melena. Urgent upper endoscopy revealed multiple 'downhill' esophageal varices with stigmata of recent hemorrhage. As there was no active bleeding, no endoscopic intervention was performed. CT angiography demonstrated stenosis of the SVC surrounding the distal tip of her indwelling hemodialysis catheter. The patient underwent balloon angioplasty of the stenotic SVC segment with resolution of her bleeding and clinical stabilization. Downhill esophageal varices are a distinct entity from the more common distal esophageal varices. Endoscopic therapies have a role in temporizing active variceal bleeding, but relief of the underlying SVC obstruction is the cornerstone of treatment and should be pursued as rapidly as possible. It is unknown why benign, as opposed to malignant, causes of SVC obstruction result in bleeding from downhill varices at such a high rate, despite being a less common etiology of SVC obstruction.
Full Text Available Throughout the world today there are about 80 countries which practice various winter sports. Regardless of the wide geographical range demand in terms of existing infrastructure is highly concentrated in a few regions of the world. To be competitive ski resorts have to deliver good experiences and excellent value to tourists. Current community officials and destination managers of the Bulgarian ski resort of Bansko believe that the main weakness of this ski centre is the extensive waiting at the bottom gondola station and advocates expansion of the ski runs and lift capacity. The aim of the article is to research the strengths and weaknesses of the resort in regional and world context and to prove that further expansion will not forge a strong emotional connection with visitors and thus will not bring success in destination markets. The methodology used in this article follows three steps: 1 Literature review on the nature of the ski market in the world, as well as factors contributing to effective destination management; 2 International, national and regional data analysis of existing secondary data on winter sports market and 3 Qualitative study carried out with a purposive sample of key informants. The SWOT analysis based on the results of the qualitative study show that touristic shareholders in Bansko should apply an appropriate strategy for small winter resorts by offering a unique product that speaks to the world instead of trying to promote universal broad product for the mass market.
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... Gymnastics G Downhill skiing DS Team sports T (soccer, volleyball, basketball, etc.) Ice skating I Rowing, canoeing ... PhD Professor Emeritus of Pediatrics and Exercise and Nutrition Sciences Woman’s and Children’s Hospital of Buffalo and ...
Holleczek, Thomas; Tröster, Gerhard
We develop and investigate a particle-based model for ski slope traffic. Skiers are modeled as particles with a mass that are exposed to social and physical forces, which define the riding behavior of skiers during their descents on ski slopes. We also report position and speed data of 21 skiers recorded with GPS-equipped cell phones on two ski slopes. A comparison of these data with the trajectories resulting from computer simulations of our model shows a good correspondence. A study of the relationship among the density, speed, and flow of skiers reveals that congestion does not occur even with arrival rates of skiers exceeding the maximum ski lift capacity. In a sensitivity analysis, we identify the kinetic friction coefficient of skis on snow, the skier mass, the range of repelling social forces, and the arrival rate of skiers as the crucial parameters influencing the simulation results. Our model allows for the prediction of speed zones and skier densities on ski slopes, which is important in the prevention of skiing accidents.
Davidson, T M; Laliotis, A T
Snowboarding is a rapidly growing winter sport. Its unorthodox maneuvers and young participants raise many safety concerns. We examined injury patterns in recreational snowboarders, comparing these patterns with those found in alpine skiers. Snowboarding and skiing injury patterns differed significantly (P knee (17% versus 39%) or thumb (2% versus 4%) injuries than skiers. For snowboarders, wrist injuries were most common in beginners (30%), knee injuries in low intermediates (28%), ankle injuries in intermediates (17%), and shoulder or clavicle injuries in advanced snowboarders (14%). Most snowboarders (90%) wore soft-shelled boots, 73% of lower extremity injuries occurred to the lead-foot side, and 73% of wrist injuries occurred during backward falls; 67% of knee injuries occurred during forward falls. Of all injuries, 8% occurred while loading onto or unloading from a ski lift. The sport of snowboarding brings with it a different set of injuries from those seen in alpine skiing. The data focus attention on improvements such as wrist guards or splints, releasable front-foot bindings, and better instruction for beginner snowboarders to improve the safety of this sport. Finally, the data confirm that snowboarders and skiers may be safely combined on the same slopes.
The Swedish Nuclear Power Inspectorate (SKI) is an independent government agency responsible for technical assessments and information concerning accidents involving nuclear facilities at home and abroad. With the events of September 11 in New York and Washington D.C., circumstances have also changed for Swedish government agencies. Increased focus had been placed on a broadened threat spectrum, especially as concerns terrorism and the use of non-conventional weapons and methods. This means that SKI must develop adequate preparedness for new types of threats and events. What types of threats, and how SKI's preparedness planning should be developed, are questions which were addressed in a study by a working group from SKI and FOI -the Swedish National Defence Research Agency. The purpose of the study was to identify serious threats and events, which would require SKI's involvement, and to analyze what resources and competencies would by needed in order for SKI to fulfill it responsibilities. Investigating a broadened threat spectrum involves defining and analyzing a multi-dimensional problem complex, which is both difficult to quantify and involves very complicated internal relationships. Morphological analysis is a method for structuring and analyzing such problem complexes, and for developing models based on natural language concepts. The working group developed and studied ten different scenarios, which defined the parameter space for a broadened threat spectrum for SKI. On the basis of these scenarios, a morphological model was developed which describes the demands that these scenarios place on SKI as an organization. On the basis of this, a further morphological model was developed, in order to systematically dimension the resources that would be needed in the face of these demands. Through this analysis, a clearer picture of the demands and required resources for future threats has emerged. The information and insights generated will serve to better develop
Sklett, Vegard Haukø
Purpose – The present study investigated the relationship between psychological factors (self-efficacy, flow, positive- and negative affect, worry) and ski jumping performance, as well as the influential functions these psychological factors have on ski jumping performance. Method – World Cup ski jumpers (N = 40) responded to four questionnaires in the middle of the World Cup season, reporting their subjective experience during a competitive setting. Social Cognitive Theory (SCT) (Bandura...
Full Text Available The relative age effect (RAE is a well-documented phenomenon in youth sports. This effect exists when the relative age quarter distribution of selected athletes shows a biased distribution with an over-representation of relatively older athletes. In alpine ski racing, it exists in all age categories (national youth levels up to World Cup. Studies so far could demonstrate that selected ski racers are relatively older, taller and heavier. It could be hypothesized that relatively younger athletes nearly only have a chance for selection if they are early maturing. However, surprisingly this influence of the biological maturity status on the RAE could not be proven, yet. Therefore, the aim of the present study was to investigate the influence of the biological maturity status on the RAE in dependence of the level of competition. The study investigated 372 elite youth ski racers: 234 provincial ski racers (P-SR; high level of competition and 137 national ski racers (N-SR; very high level of competition. Anthropometric characteristics were measured to calculate the age at peak height velocity (APHV as an indicator of the biological maturity status. A significant RAE was present among both P-SR and N-SR, with a larger effect size among the latter group. The N-SR significantly differed in APHV from the P-SR. The distribution of normal, early and late maturing athletes significantly differed from the expected normal distribution among the N-SR, not among the P-SR. Hardly any late maturing N-SR were present; 41.7% of the male and 34% of the female N-SR of the last relative age quarter were early maturing. These findings clearly demonstrate the significant influence of the biological maturity status on the selection process of youth alpine ski racing in dependence of the level of competition. Relatively younger athletes seem to have a chance of selection only if they are early maturing.
Pauli, Carole A.; Keller, Melanie; Ammann, Fabian; Hübner, Klaus; Lindorfer, Julia; Taylor, William R.
Abstract Pauli, CA, Keller, M, Ammann, F, Hübner, K, Lindorfer, J, Taylor, WR, and Lorenzetti, S. Kinematics and kinetics of squats, drop jumps and imitation jumps of ski jumpers. J Strength Cond Res 30(3): 643–652, 2016—Squats, drop jumps, and imitation jumps are commonly used training exercises in ski jumping to enhance maximum force, explosive force, and sport-specific skills. The purpose of this study was to evaluate the kinetics and kinematics of training exercises in ski jumping and to find objective parameters in training exercises that most correlate with the competition performance of ski jumpers. To this end, barbell squats, drop jumps, and imitation jumps were measured in a laboratory environment for 10 elite ski jumpers. Force and motion data were captured, and the influence of maximum vertical force, force difference, vertical take-off velocity, knee moments, knee joint power, and a knee valgus/varus index was evaluated and correlated with their season jump performance. The results indicate that, especially for the imitation jumps, a good correlation exists between the vertical take-off velocity and the personal jump performance on the hill (R = 0.718). Importantly, however, the more the athletes tended toward a valgus knee alignment during the measured movements, the worse their performance (R = 0.729 imitation jumps; R = 0.685 squats). Although an evaluation of the athletes' lower limb alignment during competitive jumping on the hill is still required, these preliminary data suggest that performance training should additionally concentrate on improving knee alignment to increase ski jumping performance. PMID:26418370
Müller, W; Platzer, D; Schmölzer, B
This study of ski jumping includes three areas of research: Wind tunnel measurements with world class athletes in various flight positions, field measurements during the World Championships in Ski Flying 1994 in Planica (Slovenia) and a highly reliable mapping of ski jumping to a computable simulation model. The results explain the effects of equipment, flight style changes, the reason for the enhanced tumbling risk and high gust sensitivity observed. Consequences can be drawn for changes to the FIS regulations, the design of jumping hills and training methods. The internationally induced anorexia of the athletes could be prohibited by a new ski length regulation. Women jumpers could become a real competitive threat.
Roland Stöggl, Erich Müller, Thomas Stöggl
Full Text Available The aims of the current study were to analyze whether specific roller skiing tests and cycle length are determinants of youth cross-country (XC skiing performance, and to evaluate sex specific differences by applying non-invasive diagnostics. Forty-nine young XC skiers (33 boys; 13.8 ± 0.6 yrs and 16 girls; 13.4 ± 0.9 yrs performed roller skiing tests consisting of both shorter (50 m and longer durations (575 m. Test results were correlated with on snow XC skiing performance (PXC based on 3 skating and 3 classical distance competitions (3 to 6 km. The main findings of the current study were: 1 Anthropometrics and maturity status were related to boys’, but not to girls’ PXC; 2 Significant moderate to acceptable correlations between girls’ and boys’ short duration maximal roller skiing speed (double poling, V2 skating, leg skating and PXC were found; 3 Boys’ PXC was best predicted by double poling test performance on flat and uphill, while girls’ performance was mainly predicted by uphill double poling test performance; 4 When controlling for maturity offset, boys’ PXC was still highly associated with the roller skiing tests. The use of simple non-invasive roller skiing tests for determination of PXC represents practicable support for ski clubs, schools or skiing federations in the guidance and evaluation of young talent.
Full Text Available Isolated lesions to the teres major muscle are rare. They generally occur in patients participating in sports such as baseball, tennis, or boxing. We report the case of a sports patient who suffered an isolated injury to the teres major while water skiing. The clinical presentation was confirmed by MRI. Conservative treatment was chosen and consisted of brief analgesic immobilization, followed by rehabilitative treatment. The rapid recovery of this patient with normal isokinetic strength evaluation at 6 months was interesting for objectifying full muscle recovery. Our results and the data from the literature suggest that functional rather than surgical treatment is preferable in isolated lesions to the teres major muscle.
Full Text Available The students of the West University of Timişoara represent a numerous social category, thus quite significant, continuously in search of new ways to practice sports in their free time. The winter season brings to our attention a number of specific activities, most appealing, amongst which alpine skiing, too. The present paper aims at defining the students’ habits regarding the way they spend their spare time, mainly as practicing alpine skiing. This sports branch enhances its attractiveness by the very special environment it can be practiced – into the mountains, in the open air, which actually raises the students’ interest for this free time activity, mainly during the winter vacation or the vacation between semesters, when the number of students largely exceeds the number of those practicing ski during the week or in weekends. We must take into account the fact that they prefer mountain resorts in Romania, not being picky at all when it comes to meals and accommodation facilities, but very demanding about the quality of the ski slopes and the correspondent facilities. The window of time allocated for skiing activities, an average between 1-3 hours/day, illustrates the students’ interest in spending their spare time in an active way. The relatively high costs of this sports branch, mainly because of the expensive equipments but also because of the high costs of the activity itself- courses, utilities, etc.- haven’t kept the students away; they have been manifesting their availability to invest the necessary amounts of money in order to be able to practice this sport. An excellent promotion factor of the alpine skiing amongst students has been the Timisoara West University by organizing theme camps – like ski teaching, but also a number of activities related to such a camp.
This volume comprises scientific contributions in the context of the 5th annual conference of the European Association of Sports Economics (ESEA), which took place in September 2013 in Esbjerg, Denmark. It contains five articles on UEFA’s financial fair play regulation in European football, written...... by internationally renowned sports economists like Stefan Szymanski, Joel Maxcy and Sean Hamil. Moreover, a further three chapters deal with football topics like the dismissal of coaches or competitive balance. Furthermore, the economics of sports events – the Olympics as well as local events – are analyzed by well......-known scholars like Wladimir Andreff and Plácido Rodríguez. Next to team sports, new developments of the economics of individual sports like cycling, ski-jumping and motor-racing are explored....
Du Boullay, C T; Bardier, M; Cheneau, J; Bortolasso, J; Gaubert, J
Among 49 000 cases of infantile emergencies which were received in the BUCI (Bloc d'urgence chirurgical infantile: surgical infantile emergency unit), 5 546 were sport traumas. At an early age, they were caused by outdoor plays; during adolescence, the main cases were caused by team sports. Males are predominant. The number of cases has been regularly progressing, particularly since 1976. The fashion in sports is influenced by médias (i.e. skate board), and can be opposed to the continuous practice of popular sports (swimming, ball games, bycicle. There are winter, summer, school timed sports (the latter being influenced by the sportive scholar associations). The most frequent sports are cycling, football playing, swimming and horse riding, athleticism skating, Other are occasionnal. Changes in sport fashions, female increasing participation, such as horse riding and skating, democratisation (skiing, riding), the worsening of traumas; the pathology concerning bystanders, are described. Cranial and peripheric pathology are dominant. Trunk traumas are scarce but severe. Each sport has an elective pathologic localisation. Injury mechanisms are found, such as stirrup, saddle, ski baton pathology. There is traumatologic similarities; skate board and roller skating; judo and atheleticism; cycling and horse riding. Sport in children is not a replica of the one among adults. Riding a bike is not cycling. Some sports are dangerous: cycling, horse riding, rugby. A traumatological outline is revealed. Preventive measures should be taken. The socio-economical cost is heavy.
Dennis J. Caine
Full Text Available The objective of the book is to review comprehensively what is known about the distribution and determinants of injury rates in a variety of individual sports, and to suggest injury prevention measures and guidelines for further research. This book provides comprehensive compilation and critical analysis of epidemiological data over children's individual sports: including equestrian, gymnastics, martial arts, skiing and snowboarding, tennis, track and field, and wrestling. This book encourages coaches and sports administrators to discuss rules, equipment standards, techniques, and athlete conditioning programs. In turn, they can inform parents about the risks and how they can help their children avoid or limit injury in sports. A common, uniform strategy and evidence-based approach to organizing and interpreting the literature is used in all chapters. All the sports-specific chapters are laid out with the same basic headings, so that it is easy for the reader to find common information across chapters. Chapter headings are: 1 Epidemiology of children's individual sports injuries, 2 Equestrian injuries, 2 Gymnastics injuries, 3 Martial arts injuries, 4 Skiing and snowboard injuries, 5 Tennis injuries, 6 Track and field injuries, 7 Wrestling injuries, 8 Injury prevention and future research. Chapter headings include: i Incidence of injury, ii Injury characteristics, iii Injury severity, iv njury risk factors, v Suggestions for injury prevention, vi Suggestions for further research. In each sports-specific chapter, an epidemiological picture has been systematically developed from the data available in prospective cohort, retrospective cohort, case-control, and cross-sectional studies. The tables are numerous, helpful and very useful. The book provides a very useful resource for sport scientist, pediatricians, family practitioners and healthcare professionals in the field of child and adolescent injury and prevention The readers are going to
Niederseer, David; Ledl-Kurkowski, E; Kvita, K
the effects of alpine skiing on CVRF in elderly skiers. Subjects (n=42) were randomized into an intervention group (IG; n=22; 12 males/10 females; age: 66.6 ± 2.1 years) completing 12 weeks of guided skiing or a control group (CG; n=20; 10 males/10 females; age: 67.3 ± 4.4 years). CVRF were assessed before......: -2.3%, Pelderly is safe with respect to cardiovascular events, and improves some, but not all CVRF....
Lion, Alexis; Vibert, Dominique; Bosser, Gilles; Gauchard, Gérome C; Perrin, Philippe P
Vertigo has been described after the practice of mountain bike. This study aimed to investigate the prevalence of vertigo following competitions or training sessions of downhill mountain biking (DMB) or road cycling (RC). One hundred and two DMB riders, 79 road cyclists and 73 control participants filled in a survey intended to evaluate the prevalence of vertigo in daily living activities and following competitions or training sessions. Vertigo causal factors (crashes, head trauma, fatigue, characteristics of the path/road ridden) were recorded. DMB riders and road cyclists did not report more vertigo during daily living activities than controls. But DMB riders older than 30 had more risk to report vertigo than age-matched road cyclists (OR: 5.06, 95% CI: 1.23-20.62). Road cyclists aged between 20 and 29 were 2.59-fold (95% CI: 1.06-6.27) more likely to report vertigo than controls. After competitions and training sessions, DMB riders were 2.33-fold (95% CI: 1.22-4.41) more likely to report vertigo than road cyclists. Vertigo causal factors were crash with head trauma in DMB riders and fatigue in road cyclists. Vertigo during daily living activities may be of concern for cyclists, particularly older DMB riders. The accumulation of impacts (crashes, vibrations) during the career of a DMB rider may generate micro-traumatisms of the central nervous system and/or peripheral vestibular structures, particularly the otolith organs. In RC, the pathophysiological mechanisms generating vertigo might be effort-related disturbance of homeostasis. To avoid injuries, DMB riders should be aware that vertigo may occur at the end of training sessions or competitions.
Full Text Available Markus Posch,1 Martin Burtscher,1 Alois Schranz,2 Katja Tecklenburg,2 Kenneth Helle,2 Gerhard Ruedl1 1Department of Sport Science, University of Innsbruck, Innsbruck, Austria; 2Medalp Sportclinic, Imst, Austria Background and purpose: The ability to successfully self-release the ski binding can prevent skiing-related injuries of the lower extremities. Failure of binding release associated with a knee injury is significantly higher among females compared to males. The International Standards Organization ISO 11088 standard for binding setting values allows a lowering by 15% upon request of the skier. Thus, the aim of this study was to evaluate the impact of lowered ski binding settings by 15% on the outcome of the self-release test among female recreational skiers. Materials and methods: In this randomized single-blinded study, a cohort of 20 females (24.5±2.7 years performed the self-release test in the laboratory thrice with each leg under two conditions: 1 with an actual ISO 11088 setting and 2 with a setting lowered by 15%. For each attempt, torques calculated via the force plate were normalized to torques measured by a binding adjustment system (relative release torque, RRT. Results: Among 240 trials in total, more females were significantly able to self-release their ski bindings with lowered binding settings when compared to their actual ISO settings (53% vs 9%, p<0.001. Thirteen females (65% were able to release their bindings at least once with both legs with lowered binding settings compared to only three females (15% with their actual binding settings (p<0.001. Mean RRT of all failure of binding release trials significantly differed between lowered and actual binding settings (58.6%±22.2% vs 50.5%±20.4%, p=0.003. Conclusion: Four times more females were able to self-release their ski bindings at least once with both legs with a 15% lowered binding setting compared to their normal ISO 11088 setting. The fact that the ISO standard
Shaw, Andrew J; Ingham, Stephen A; Folland, Jonathan P
Running downhill, in comparison to running on the flat, appears to involve an exaggerated stretch-shortening cycle (SSC) due to greater impact loads and higher vertical velocity on landing, whilst also incurring a lower metabolic cost. Therefore, downhill running could facilitate higher volumes of training at higher speeds whilst performing an exaggerated SSC, potentially inducing favourable adaptations in running mechanics and running economy (RE). This investigation assessed the efficacy of a supplementary 8-week programme of downhill running as a means of enhancing RE in well-trained distance runners. Nineteen athletes completed supplementary downhill (-5% gradient; n = 10) or flat (n = 9) run training twice a week for 8 weeks within their habitual training. Participants trained at a standardised intensity based on the velocity of lactate turnpoint (vLTP), with training volume increased incrementally between weeks. Changes in energy cost of running (E C ) and vLTP were assessed on both flat and downhill gradients, in addition to maximal oxygen uptake (⩒O 2max). No changes in E C were observed during flat running following downhill (1.22 ± 0.09 vs 1.20 ± 0.07 Kcal kg -1 km -1 , P = .41) or flat run training (1.21 ± 0.13 vs 1.19 ± 0.12 Kcal kg -1 km -1 ). Moreover, no changes in E C during downhill running were observed in either condition (P > .23). vLTP increased following both downhill (16.5 ± 0.7 vs 16.9 ± 0.6 km h -1 , P = .05) and flat run training (16.9 ± 0.7 vs 17.2 ± 1.0 km h -1 , P = .05), though no differences in responses were observed between groups (P = .53). Therefore, a short programme of supplementary downhill run training does not appear to enhance RE in already well-trained individuals.
Sherry, E; Asquith, J
A retrospective study of 88 nordic skiing injuries from the 1984 and 1985 skiing seasons in Australia is presented. To our knowledge, this is the largest study to date of such injuries. These injuries are compared with alpine skiing injuries from the same medical clinic for the 1985 skiing season. There was a much lower incidence of injury from nordic skiing; however, when injuries did occur, they tended to be more serious than those of alpine skiing and frequently required immediate evacuation to hospital for treatment. As the nordic skier is relatively isolated from medical services, these findings need to be considered in the future planning of rescue services for such skiers.
... Staying Safe Videos for Educators Search English Español Sports Physicals KidsHealth / For Teens / Sports Physicals What's in ... beginning of your sports season. What Is a Sports Physical? In the sports medicine field, the sports ...
In this report a set of parameter values for transport calculations is given for the safety assessment of a deep geological repository in crystalline rock. The selected data are intended for use in the performance assessment exercise of SKI, Project 90. Thus, they are primarily to be used for testing of transport models and evaluation of model performance, and the listed data must not be regarded as a set recommended for licensing purposes. 'Best estimates' are given for solubilities and sorption (distribution) data. Ranges of data are also provided that should be used to evaluate, e.g. by means of variational analysis, the need for more efforts in areas such as site characterization, geochemical modelling or review of thermodynamical data bases. Since the Project 90 performance assessment calculations are based on a synthetic site, without the possibility of correlation of hydraulic and geochemical parameters, the data given are generic for a typical Swedish crystalline rock. This also means that the ranges given are much broader than would be the case for a data set founded on site specific information (40 refs.) (au)
Leonardo Coelho Rabello de Lima
Full Text Available DOI: http://dx.doi.org/10.5007/1980-0037.2015v17n5p539 Eccentric exercise training using low intensity-high volume approach has been performed to improve maximal muscle strength and power. The aim of this study was to compare the effects of short-term downhill walking and level walking training on lower limb strength and maximal oxygen uptake of active individuals. Eighteen young adults were divided into level walking group (n = 9 or downhill walking training group (n = 9. Both groups performed a four-week training program. The level walking group performed seven level walking sessions per week, while the downhill walking group walked downhill (-16% in the same weekly frequency. One week before and one week after the training protocol, maximal oxygen uptake, muscle-bone cross-sectional area and isometric peak torque of knee extensors and plantar flexors were assessed for both groups. A significant group vs. time interaction was found only for cross sectional area of plantar flexors (PF, showing increases for the downhill walking group (112.6 ± 28.9 cm2 vs. 115.9 ± 29 cm2 but not for the level walking group (94.9 ± 23.3 cm2vs. 94.6 ± 228 cm2. Maximal oxygen uptake remained unaltered after training for both groups and IPT was increased after training for both groups. It was concluded that short-term downhill walking training does not seem to be efficient in promoting improvements in cardiorrespiratory fitness of young adults. However, it seems to promote gains in some variables related to neuromuscular fitness
Full Text Available Sport Tourism is a form of relaxation and active leisure based on motric activities that contribute to health maintenance. The social dimension of sport tourism results from its ability to mobilize large masses of the population to participate in recreational activities and to contribute to the pursuit of project development and exploiting potentially attractive regions (tourist resorts, recreational complexes, etc.. At the level of Bistriţa-Năsăud County, organising and pursuing sport tourism is based on three fundamental elements: natural resources, infrastructure, and tourism sport tradition. Among sport tourism activities, following are noteworthy: cycling tourism, hiking, horseback riding, swimming, navigation, skiing, paragliding, alpine skiing, ski touring, enduro, etc.
SKI (the Swedish Nuclear Power Inspectorate) has sent SKB`s (the Swedish Nuclear Fuel and Waste Management Co.) RD and D Programme 95 to sixty authorities and organizations for review. 35 reviewing bodies have replied. In various ways, most of the comments are related to the decision-making process, both with regard to site selection and choice of method and only a small number of reviewing bodies have dealt with the more purely technical issues such as the function of the barriers and the safety assessment methodology. SKI`s review of the programme is based on the premises of establishing whether and how the programme can fulfill its actual purpose to identify and implement solutions for the final disposal of the spent nuclear fuel from the Swedish nuclear power plants. SKI`s statement to the Government includes a `Summary and Conclusions` of the `Review Report`. In (the present) `Review Report` SKI reviews the programme and deals with comments from the other reviewing bodies. Furthermore, SKI has commissioned a separate report with the `Comments of the Reviewing Bodies`. 32 refs.
..., local, or tribal government or anyone in the private sector. Therefore, a statement under section 202 of... DEPARTMENT OF AGRICULTURE Forest Service 36 CFR Part 251 RIN 0596-AD12 Definition of a Ski Area... definition of a ski area in its regulations to make it consistent with the authority in section 3 of the Ski...
Full Text Available Winter sports occupy a prominent place in European tourism, not only because of their economic importance in mountainous areas but also due to their major symbolic significance in the "leisure civilisation". Yet the world of winter tourism is full of uncertainties connected with climate change and also with evolutions and structural breaks that call into question the development model on which it is based. This context of profound change gives us the opportunity to question the limits of the industrial model that has governed the development of the Alps for the practice of skiing and to examine alternative future scenarios to "all-out skiing" and even "all-out tourism".Les sports d’hiver occupent une place de premier plan dans le tourisme européen, non seulement du fait de leur poids économique dans les régions de montagne, mais aussi par leur forte dimension symbolique dans la « civilisation des loisirs ». Pourtant l’univers du tourisme hivernal est parcouru par de nombreuses incertitudes liées au changement climatique, mais aussi à des évolutions et des ruptures structurelles qui remettent en question le modèle de développement sur lequel il repose. Ce contexte de mutation permet d’interroger les limites du modèle industriel qui a présidé à l’aménagement des Alpes pour la pratique du ski et d’examiner des figures d’avenir alternatives au « tout ski » et même au « tout tourisme ».
Most of the breaking force in the speed disciplines in alpine skiing is caused by the aerodynamic drag, and a better knowledge of the drag force is therefore desirable to gain time in races. In this study a complete database of how the drag area (CDA) changes, with respect to the different body segments, was made and used to explain a complete body motion in alpine skiing. Three experiments were performed in the wind tunnel at NTNU, Trondheim. The database from a full body measurement on an a...
Birn-Jeffery, Aleksandra V; Higham, Timothy E
Geckos employ their adhesive system when moving up an incline, but the directionality of the system may limit function on downhill surfaces. Here, we use a generalist gecko to test whether limb modulation occurs on downhill slopes to allow geckos to take advantage of their adhesive system. We examined three-dimensional limb kinematics for geckos moving up and down a 45° slope. Remarkably, the hind limbs were rotated posteriorly on declines, resulting in digit III of the pes facing a more posterior direction (opposite to the direction of travel). No significant changes in limb orientation were found in any other condition. This pes rotation leads to a dramatic shift in foot function that facilitates the use of the adhesive system as a brake/stabilizer during downhill locomotion and, although this rotation is not unique to geckos, it is significant for the deployment of adhesion. Adhesion is not just advantageous for uphill locomotion but can be employed to help deal with the effects of gravity during downhill locomotion, highlighting the incredible multi-functionality of this key innovation. © 2014 The Author(s) Published by the Royal Society. All rights reserved.
Skis in which part of the material consists of birch wood impregnated with the basic chemicals of plastic and then irradiated are now undergoing tests. They are a demonstration of the new material created when this technique is applied to wood and fibres. (author)
SKI's research is a prerequisite for SKI's ability to fulfil its assignment. Research to support supervision is focused today on a number of strategically important areas such as reactor technology, material and fuel questions, human factors, waste and non-proliferation (safeguards). SKI's intelligence analysis shows that this focus should be maintained over the next few years. Some reallocation of priorities between research areas may be necessary due to changes in the nuclear area. For this research, SKI contracts universities as well as consulting companies. The resources that are of importance for nuclear research are concentrated to a few organisations in Sweden. But the national research resources alone do not cover the existing needs. One reason is that the previously highly competent and well funded Swedish expert organisations within the nuclear power utilities have gradually been phased out or transformed into consulting firms. Changes have also taken place at the Swedish vendor of boiling-water plants, now Westinghouse Atom, and the activities have been down sized considerably in Sweden. There has been a similar trend in other countries. Moreover, countries which previously conducted expensive experiments have themselves increasingly sought international support as their research resources have dwindled. As a result, numerous international projects have or are planned to be started. SKI notes that Swedish nuclear activities are also becoming increasingly dependent on international collaboration. SKI further notes that in order to fulfil its assignment, the Inspectorate needs not only financial resources but also competent personnel. This enables targeted support to be maintained to strategic national infrastructure and to international cooperation including internationally financed projects. With this is meant above all experimental research where small countries such as Sweden can join forces with other countries on to important research
Woermann, Niklas; Wieser, Verena
Remedying the absence of a cultural theory of consumption skill acquisition, we use video data to explore how consumers learn in ski schools. We identify six modes of skill acquisition and theorize the interplay between the sensori-motor system, the conscious state of skillful coping...
Heus, R.; Schols, E.; Kistemaker, L.
Previous research have showed that cold injuries of feet occur more often than cold injuries of hands. Recently, an unexpectedly large number of cold injuries were observed during military training in Norway and a relationship between cold injuries and the use of the Alico ski boot was suspected.
The changed skiing-technique with more knee flexion (so called jet-position) has lead to rising pressures in the femoro-patellar joint. The danger of traumatic and arthritic diseases has increased as well. We suggest to avoid extreme anteflexed crural position in the ski-boots (more than 5 degrees). It should be possible to walk and stand in ski-boots without pressure on the knee-joint. This problem is most important in the growing locomotor system.
Full Text Available Purpose: to scientifically substantiate effective mechanisms of organism’s bio-chemical adaptation of ski-racers in competition period with the help of lipid peroxidation indicators, oxidative modification of proteins and activity of hypothalamus pituitary adrenocortical system. Material: in the research 14 sportsmen of 18-25 years’ age (combined team of university with different level of sportsmanship participated. Assessment of free radical oxidation, anti-oxidant system, cortisol level was fulfilled with the help of indicators’ quantitative analysis by bio-chemical methods applied to blood serum samples. Results: it was found that in the basis of bio-chemical changes under intensive physical loads is increase of catabolic processes’ speed. Change of organism’s metabolic orientation of ski racers at optimal level results in working muscles’ energy supply improvement, increase of energy systems’ power and sports efficiency. Conclusions: Application of interval trainings at stages of preparation to special significant competitions results in expected adaptation and increase of sports efficiency. We also showed their effective role in ensuring long term reactions, conditioning high sports efficiency.
Mote, C D; Hull, M L
1. The static adjustment of a ski binding by hand or by available machines is only an adjustment and is neither a static nor a dynamic evaluation of the binding design. Bindings of different design with identical static adjustments will perform differently in environments in which the forces are static or dynamic. 2. The concept of binding release force is a useful measure of binding adjustment, but it is inappropriate as a criterion for binding evaluation. First, it does not direct attention toward the injury causing mechanism, strain, or displacement in the leg. Second, it is only part of the evaluation in dynamic problems. 3. The binding release decision in present bindings is displacement controlled. The relative displacement of the boot and ski is the system variable. For any specified relative displacement the binding force can be any of an infinite number of possibilities determined by the loading path. 4. The response of the leg-ski system to external impulses applied to the ski is independent of the boot-ski relative motion as long as the boot recenters quickly in the binding. Response is dependent upon the external impulse plus system inertia, damping and stiffness. 5. When tested under half sinusoidal forces applied to a test ski, all bindings will demonstrate static and impulse loading regions. In the static region the force drives the binding to a relative release displacement. In the impulse region the initial velocity of the ski drives the binding to a release displacement. 6. The transition between the static and impulse loading regions is determined by the binding's capacity to store and dissipate energy along the principal loading path. Increased energy capacity necessitates larger external impulses to produce release. 7. In all bindings examined to date, the transmitted leg displacement or strain at release under static loading exceeds leg strain under dynamic or impact loading. Because static loading is responsible for many injuries, a skier
Natri, A; Beynnon, B D; Ettlinger, C F; Johnson, R J; Shealy, J E
In spite of the fact that the overall incidence of alpine ski injuries has decreased during the last 25 years, the incidence of serious knee sprains usually involving the anterior cruciate ligament (ACL) has risen dramatically since the late 1970s. This trend runs counter to a dramatic reduction in lower leg injuries that began in the early 1970s and to date has lowered the risk of injury below the knee by almost 90%. One of the primary design objectives of modern ski boots and bindings has been to protect the skier from tibia and ankle fractures. So, in that sense, they have done an excellent job. However, despite advances in equipment design, modern ski bindings have not protected the knee from serious ligament trauma. At the present time, we are unaware of any binding design, settings or function that can protect both the knee and lower extremities from serious ligament sprains. No innovative change in binding design appears to be on the horizon that has the potential to reduce the risk of these severe knee injuries. Indeed, only 1 study has demonstrated a means to help reduce this risk of serious knee sprains, and this study involved education of skiers, not ski equipment. Despite the inability of bindings to reduce the risk of severe knee injuries there can be no doubt that improvement in ski bindings has been the most important factor in the marked reduction in incidence of lower leg and ankle injuries during the last 25 years. The authors strongly endorse the application of present International Standards Organisation (ISO) and American Society for Testing and Materials (ASTM) standards concerning mounting, setting and maintaining modern 'state of the art' bindings.
Gilgien, Matthias; Spörri, Jörg; Chardonnens, Julien; Kröll, Josef; Limpach, Philippe; Müller, Erich
In the sport of alpine skiing, knowledge about the centre of mass (CoM) kinematics (i.e. position, velocity and acceleration) is essential to better understand both performance and injury. This study proposes a global navigation satellite system (GNSS)-based method to measure CoM kinematics without restriction of capture volume and with reasonable set-up and processing requirements. It combines the GNSS antenna position, terrain data and the accelerations acting on the skier in order to approximate the CoM location, velocity and acceleration. The validity of the method was assessed against a reference system (video-based 3D kinematics) over 12 turn cycles on a giant slalom skiing course. The mean (± s) position, velocity and acceleration differences between the CoM obtained from the GNSS and the reference system were 9 ± 12 cm, 0.08 ± 0.19 m · s(-1) and 0.22 ± 1.28 m · s(-2), respectively. The velocity and acceleration differences obtained were smaller than typical differences between the measures of several skiers on the same course observed in the literature, while the position differences were slightly larger than its discriminative meaningful change. The proposed method can therefore be interpreted to be technically valid and adequate for a variety of biomechanical research questions in the field of alpine skiing with certain limitations regarding position.
... Staying Safe Videos for Educators Search English Español Sports Supplements KidsHealth / For Teens / Sports Supplements What's in ... really work? And are they safe? What Are Sports Supplements? Sports supplements (also called ergogenic aids ) are ...
Conclusion: Use of cryotherapy after exercise with eccentric contractions was effective to reestablish the level of biochemical markers of muscle damage and reduce muscle soreness and pain perception in subjects submitted to downhill running.
Randjelovic, Stefan; Heir, Stig; Nordsletten, Lars; Bere, Tone; Bahr, Roald
Although injury risk in Freestyle Ski Cross (SX) is high, little is known about the situations leading up to time-loss injuries. To describe the situations leading up to time-loss injuries in elite Freestyle SX. Descriptive video analysis. Thirty-three video recordings of SX injuries reported through the International Ski Federation Injury Surveillance System for four World Cup seasons (2006/2007 through 2010) were obtained. Five experts in the fields of sport medicine and SX analysed each case to describe in detail the situation leading up to the injury (skiing situation and skier behaviour). Injuries occurred in four different skiing situations: jumping (n=16), turning (n=8), jumping and turning (n=7) and rollers (n=2). All injured skiers lost control before time of injury (n=33), due to skier-opponent contact (n=13), technical errors (n=8) or inappropriate strategy (n=8), which led to a fall (n=29). Contact occurred in 21 of 33 cases, usually unintentional at landing or take-off, caused by the opponent (n=11) or injured skier (n=8). The technical error cases (n=8) were dominated by bad jumping technique (n=6) and too much inside lean in turning situations (n=2), while inappropriate course line and bad timing at take off (n=7) dominated the inappropriate strategy cases (n=8). We identified four main injury situations in elite SX, dominated by jumping situations. The primary cause of injury was unintentional skier-opponent contact in jumping, bank turning and roller situations. Another common cause of injury was personal errors (inappropriate technique and strategy) at take-off and in turning situations.
Lee, Hyo Taek; Roh, Hyo Lyun; Kim, Yoon Sang
[Purpose] Efficient management using exercise programs with various benefits should be provided by educational institutions for children in their growth phase. We analyzed the heart rates of children during ski simulator exercise and the Harvard step test to evaluate the cardiopulmonary endurance by calculating their post-exercise recovery rate. [Subjects and Methods] The subjects (n = 77) were categorized into a normal weight and an overweight/obesity group by body mass index. They performed each exercise for 3 minutes. The cardiorespiratory endurance was calculated using the Physical Efficiency Index formula. [Results] The ski simulator and Harvard step test showed that there was a significant difference in the heart rates of the 2 body mass index-based groups at each minute. The normal weight and the ski-simulator group had higher Physical Efficiency Index levels. [Conclusion] This study showed that a simulator exercise can produce a cumulative load even when performed at low intensity, and can be effectively utilized as exercise equipment since it resulted in higher Physical Efficiency Index levels than the Harvard step test. If schools can increase sport durability by stimulating students' interests, the ski simulator exercise can be used in programs designed to improve and strengthen students' physical fitness.
FREPPAZ MICHELE; FILIPPA GIANLUCA; CAIMI ANGELO; ZANINI ERMANNO
Tourism has many potential benefits for rural areas, being an important source of jobs for nonmetro communities, especially for those that are economically underdeveloped. The traditional use of lands in mountain regions is combined nowadays with surfaces devoted to recreational activities because of increasing tourist demand for winter sports. Winter-based ski tourism is a major human use of many mountain regions, with large-scale ski resorts in Europe, Asia, North and South America, New Zea...
Baumann, Cory W; Green, Michael S; Doyle, J Andrew; Rupp, Jeffrey C; Ingalls, Christopher P; Corona, Benjamin T
Contraction-induced muscle injury may reduce running economy (RE) by altering motor unit recruitment, lowering contraction economy, and disturbing running mechanics, any of which may have a deleterious effect on endurance performance. The purpose of this study was to determine if RE is reduced 2 days after performing injurious, low-intensity exercise in 11 healthy active men (27.5 ± 5.7 years; 50.05 ± 1.67 VO2peak). Running economy was determined at treadmill speeds eliciting 65 and 75% of the individual's peak rate of oxygen uptake (VO2peak) 1 day before and 2 days after injury induction. Lower extremity muscle injury was induced with a 30-minute downhill treadmill run (6 × 5 minutes runs, 2 minutes rest, -12% grade, and 12.9 km·h(-1)) that elicited 55% VO2peak. Maximal quadriceps isometric torque was reduced immediately and 2 days after the downhill run by 18 and 10%, and a moderate degree of muscle soreness was present. Two days after the injury, steady-state VO2 and metabolic work (VO2 L·km(-1)) were significantly greater (4-6%) during the 65% VO2peak run. Additionally, postinjury VCO2, VE and rating of perceived exertion were greater at 65% but not at 75% VO2peak, whereas whole blood-lactate concentrations did not change pre-injury to postinjury at either intensity. In conclusion, low-intensity downhill running reduces RE at 65% but not 75% VO2peak. The results of this study and other studies indicate the magnitude to which RE is altered after downhill running is dependent on the severity of the injury and intensity of the RE test.
We describe an original protocol Treating Depression Downhill (TDD) that was designed as a specific therapy for depression. Evolutionary theories of depression served as a basis for its development. We discuss the rationale for using evolutionary theory and describe the structure and integrative nature of TDD. We then present an observation on TDD’s application to group therapy of active duty military personnel. In the...
William A. Leuschner
Describes the skiers and ski areas in the Midwest. Analyzes market structure for the industry, the factors associated with financial success, the impact of spending on local economies, and the potential of ski area investment. Includes ski area financial statements.
Patricios, Jon S; Hislop, Michael David; Aubry, Mark; Bloomfield, Paul; Broderick, Carolyn; Clifton, Patrick; Ellenbogen, Richard G; Falvey, Éanna Cian; Grand, Julie; Hack, Dallas; Harcourt, Peter Rex; Hughes, David; McGuirk, Nathan; Meeuwisse, Willem; Miller, Jeffrey; Parsons, John T; Richiger, Simona; Sills, Allen; Moran, Kevin B; Shute, Jenny; Raftery, Martin
The 2017 Berlin Concussion in Sport Group Consensus Statement provides a global summary of best practice in concussion prevention, diagnosis and management, underpinned by systematic reviews and expert consensus. Due to their different settings and rules, individual sports need to adapt concussion guidelines according to their specific regulatory environment. At the same time, consistent application of the Berlin Consensus Statement’s themes across sporting codes is likely to facilitate superior and uniform diagnosis and management, improve concussion education and highlight collaborative research opportunities. This document summarises the approaches discussed by medical representatives from the governing bodies of 10 different contact and collision sports in Dublin, Ireland in July 2017. Those sports are: American football, Australian football, basketball, cricket, equestrian sports, football/soccer, ice hockey, rugby league, rugby union and skiing. This document had been endorsed by 11 sport governing bodies/national federations at the time of being published. PMID:29500252
Virmavirta, M; Kivekäs, J; Komi, P V
The effect of aerodynamic forces on the force-time characteristics of the simulated ski jumping take-off was examined in a wind tunnel. Vertical and horizontal ground reaction forces were recorded with a force plate installed under the wind tunnel floor. The jumpers performed take-offs in non-wind conditions and in various wind conditions (21-33 m s(-1)). EMGs of the important take-off muscles were recorded from one jumper. The dramatic decrease in take-off time found in all jumpers can be considered as the result of the influence of aerodynamic lift. The loss in impulse due to the shorter force production time with the same take-off force is compensated with the increase in lift force, resulting in a higher vertical velocity (V(v)) than is expected from the conventional calculation of V(v) from the force impulse. The wind conditions emphasized the explosiveness of the ski jumping take-off. The aerodynamic lift and drag forces which characterize the aerodynamic quality of the initial take-off position (static in-run position) varied widely even between the examined elite ski jumpers. According to the computer simulation these differences can decisively affect jumping distance. The proper utilization of the prevailing aerodynamic forces before and during take-off is a very important prerequisite for achieving a good flight position.
With reference to a chiasma contusion, proved at autopsy, sustained by a football player after a temporal impression fracture due to contact of a knee with his skull, the pathological mechanism causing chiasma injuries in blunt head injuries is explained. Finally, from our own experience we report on 2 water-sports accidents sustained by young men (a jump from the trampoline, and a fall during water-skiing) where chiasma-lesions were diagnosed from typical field defects.
Full Text Available This paper presents an approach to estimate the attitude of skis for an entire ski jump using wearable, MEMS-based, low-cost Inertial Measurement Units (IMUs. First of all, a kinematic attitude model based on rigid-body dynamics and a sensor error model considering bias and scale factor error are established. Then, an extended Rauch-Tung-Striebel (RTS smoother is used to combine measurement data provided by both gyroscope and magnetometer to achieve an attitude estimation. Moreover, parameters for the bias and scale factor error in the sensor error model and the initial attitude are determined via a maximum-likelihood principle based parameter estimation algorithm. By implementing this approach, an attitude estimation of skis is achieved without further sensor calibration. Finally, results based on both the simulated reference data and the real experimental measurement data are presented, which proves the practicability and the validity of the proposed approach.
Stöggl, R; Müller, E; Stöggl, T
The purposes were to validate whether general motor abilities and anthropometrics are determinants of youth cross-country (XC) skiing performance; evaluate gender-specific differences; and to establish noninvasive diagnostics. Fifty-one youth XC skiers (34 boys; 13.8 ± 0.6 years and 17 girls; 13.4 ± 0.9 years) performed motor skill and laboratory tests, and anthropometric data were collected and correlated with XC skiing performance. Anthropometrics and maturity status were related to boys but not to girls XC skiing performance. Push-ups and 20-m sprint were correlated to XC skiing performance in both boys and girls. XC skiing performance of boys was predominantly influenced by upper body and trunk strength capacities (medicine ball throw, push-ups, and pull-ups) and jumping power (standing long and triple jump), whereas XC skiing of girls was mainly influenced by aerobic capacities (3000-m run). Laboratory measures did not reveal greater correlations to XC skiing performance compared with simple test concepts of speed, strength, and endurance. Maturity was a major confounding variable in boys but not girls. Use of noninvasive simple test concepts for determination of upper body strength, speed, and endurance represent practicable support for ski clubs, schools, or skiing federations in the guidance and evaluation of young talent, being aware of the effect of maturity especially in boys. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Ski tourism is an economically and culturally important industry in many parts of Europe. A growing number of studies in Europe, North America, Japan, and Australia have concluded that climate change has potentially serious implications for the sustainability of ski operations by reducing the average length of ski seasons and, where applicable, increasing snowmaking costs. To date, however, the climate change risk awareness and adaptive responses of stakeholders in the ski industry have not been examined. A survey of managers at low elevation ski areas in Austria was undertaken to explore their perceptions of climate change (past and future), how climate change had/will affect their operations, and their adaptive responses (past and planned). The results indicate that climate change is not perceived to be a serious threat to ski operations and that with technological adaptation, principally snowmaking, ski area managers believe they will be able to effectively cope with climate change in the 21st century. The consequences of these perceptions for the future operation of these ski areas are discussed and conclusions drawn for the future of ski tourism in Austria.
... caused by: Sports injuries. Shoulder dislocation is a common injury in contact sports, such as football and hockey, and in sports that may involve falls, such as downhill skiing, gymnastics and volleyball. ... is a common source of dislocation. Falls. You may dislocate your ...
Stöggl, Thomas; Müller, Erich; Lindinger, Stefan
The aims of the study were to: (1) adapt the "double-push" technique from inline skating to cross-country skiing; (2) compare this new skiing technique with the conventional skate skiing cross-country technique; and (3) test the hypothesis that the double-push technique improves skiing speed in a short sprint. 13 elite skiers performed maximum-speed sprints over 100 m using the double-push skate skiing technique and using the conventional "V2" skate skiing technique. Pole and plantar forces, knee angle, cycle characteristics, and electromyography of nine lower body muscles were analysed. We found that the double-push technique could be successfully transferred to cross-country skiing, and that this new technique is faster than the conventional skate skiing technique. The double-push technique was 2.9 +/- 2.2% faster (P push technique had a longer cycle length and a lower cycle rate, and it was characterized by higher muscle activity, higher knee extension amplitudes and velocities, and higher peak foot forces, especially in the first phase of the push-off. Also, the foot was more loaded laterally in the double-push technique than in the conventional skate skiing technique.
Böhm, Harald; Senner, Veit
Ski boots are designed to transfer high forces from the skier to the ski. For this purpose they are made of stiff materials and constrain the leg of the skier to an unnatural position. To overcome the problem of unnatural knee posture, the ski boots can be adjusted in the frontal plane as well as in the horizontal plane by the canting mechanism and the "v-position", respectively. Canting enables lateral and medial orientation of the shaft with respect to the base of the boot. The "v-position" is a pronounced outward rotation of the boot's base with respect to the ski's long axis. The purpose of this study is to investigate the effect of different foot rotations and ski boot canting settings on knee kinematics during standing and simulated skiing. Knee kinematics was measured by means of motion analysis and with the help of skin-mounted markers on 20 subjects. The ski boots in their standard settings significantly constrained the skier to an unnatural valgus position. Ski boot base rotation had a significant effect on internal external knee rotation, whereas canting had an effect on varus-valgus angles during standing. However, for the simulated skiing position no effects were observed. The study suggests that the constraints of the ski boots result in a clinically relevant valgus misalignment. Canting settings reduced the misalignment but only by about 10%. Increased ski boot canting settings would therefore be desirable. Knee kinematics showed that rotational misalignment could not be linked to any significant increase in injury risk.
Jung, Daehan; Bang, Kyeongtae; Kim, Heesu; Ahn, Eunhye; Choi, Haecheon
In a ski jumping competition, it is essential to analyze the effect of various posture parameters of a ski jumper to achieve a longer flight distance. For this purpose, we construct a model of a ski jumper by using three-dimensional surface data obtained by scanning a ski jumper's body (Mr. Chil-Ku Kang, member of the Korean national team). An experiment on this model is conducted in a wind tunnel. We consider four posture parameters (forward leaning angle, ski opening angle, ski rolling angle, and ski spacing) and measure the drag and lift forces for various flight postures at various angles of attack (α = 0° - 40°) and Reynolds numbers (Re = 5.4 × 105 - 1.6 × 106) based on the length of the jump ski. Then, we derive optimum values of posture parameters for maximum lift-to-drag ratio using a response surface method. We also conduct a full-scale wind tunnel experiment with members of the Korean national team and confirm the results obtained from the experiment on the model. Supported by the NRF program (2014M3C1B1033848).
Lee, Jungil; Lee, Hansol; Kim, Woojin; Choi, Haecheon
In a ski jumping competition, it is essential to analyze the effect of various posture parameters of a ski jumper to achieve a longer flight distance. For this purpose, we conduct a large eddy simulation (LES) of turbulent flow past a model ski jumper which is obtained by 3D scanning a ski jumper's body (Mr. Chil-Ku Kang, member of the Korean national team). The angle of attack of the jump ski is 30° and the Reynolds number based on the length of the jump ski is 540,000. The flow statistics including the drag and lift coefficients in flight are in good agreements with our own experimental data. We investigate the flow characteristics such as the flow separation and three-dimensional vortical structures and their effects on the drag and lift. In addition to LES, we construct a simple geometric model of a ski jumper where each part of the ski jumper is modeled as a canonical bluff body such as the sphere, cylinder and flat plate, to find its optimal posture. The results from this approach will be compared with those by LES and discussed. Supported by NRF program (2014M3C1B1033848, 2014R1A1A1002671).
This book is intended for people who desire to improve their skiing by exploring high performance techniques leading to: (1) more consistent performance; (2) less fatigue and more endurance; (3) greater strength and flexibility; (4) greater versatility; (5) greater confidence in all skiing conditions; and (6) the knowledge to participate in…
Duoos, Bridget A.
Part I of Kick, Glide, Pole! Cross-Country Skiing Fun, which was published in last issue, discussed how to select cross-country ski equipment, dress for the activity and the biomechanics of the diagonal stride. Part II focuses on teaching the diagonal stride technique and begins with a progression of indoor activities. Incorporating this fun,…
Hydren, Jay R; Kraemer, William J; Volek, Jeff S; Dunn-Lewis, Courtenay; Comstock, Brett A; Szivak, Tunde K; Hooper, David R; Denegar, Craig R; Maresh, Carl M
Thousands of youth athletes travel to high altitude to participate in lift-access alpine sports. The purpose of this study was to examine the impact of acute high-altitude exposure on balance, choice reaction time, power, quickness, flexibility, strength endurance, and V[Combining Dot Above]O2max in youth lowlander athletes during a weeklong preseason training camp in Summit County, CO, USA. Eleven youth ski racers (4 boys and 7 girls; age, 13.7 ± 0.5 years; height, 157.2 ± 12.6 cm; weight, 52.4 ± 6.8 kg) with 7.7 ± 2.2 skiing years of experience participated in baseline testing at 160 m one week before the camp and a set of daily tests in the morning and afternoon at 2,828 m and skied between 3,328 and 3,802 m during a 6-day camp. Balance and choice reaction time tests were stagnant or improved slightly during the first 3 days and then improved on days 4 and 6. Vertical jump, flexibility, T-agility test, and push-ups in 1 minute improved on day 6. The number of sit-ups in 1 minute did not improve, and scores on the multistage fitness test decreased 20.34%. There was no effect of Lake Louise acute mountain sickness (AMS) questionnaire scores on performance variables measured. Athletes sojourning to high altitude for ski camps can train on immediate ascent but should slowly increase training volume over the first 3 days. Athletes should expect improvements in balance and reaction time 3-6 days into acclimatization. Coaches and athletes should expect about 20% of youth lowlander athletes to have signs and symptoms of AMS during the first 3 days of altitude exposure for alpine lift access sports at altitudes of up to 3,800 m.
Full Text Available Objectives: The aim of the study was to investigate whether a ski helmet interferes with the sound localization and the time of sound perception in the frontal plane. Material and Methods: Twenty-three participants (age 30.7±10.2 were tested on the slope in 2 conditions, with and without wearing the ski helmet, by 6 different spatially distributed sound stimuli per each condition. Each of the subjects had to react when hearing the sound as soon as possible and to signalize the correct side of the sound arrival. Results: The results showed a significant difference in the ability to localize the specific ski sounds; 72.5±15.6% of correct answers without a helmet vs. 61.3±16.2% with a helmet (p < 0.01. However, the performance on this test did not depend on whether they were used to wearing a helmet (p = 0.89. In identifying the timing, at which the sound was firstly perceived, the results were also in favor of the subjects not wearing a helmet. The subjects reported hearing the ski sound clues at 73.4±5.56 m without a helmet vs. 60.29±6.34 m with a helmet (p < 0.001. In that case the results did depend on previously used helmets (p < 0.05, meaning that that regular usage of helmets might help to diminish the attenuation of the sound identification that occurs because of the helmets. Conclusions: Ski helmets might limit the ability of a skier to localize the direction of the sounds of danger and might interfere with the moment, in which the sound is firstly heard.
Doyscher, R; Kraus, K; Finke, B; Scheibel, M
During sports the shoulder complex is exposed to considerable load especially where throwing is important and various pathological changes can occur. In the last two decades the shoulder in athletes has become a special term in clinical sports medicine Selective literature review in PubMed and consideration of personal experience, research results as well as national and international recommendations In general acute lesions of the shoulder caused by sudden sport injuries, such as traumatic luxation, acromioclavicular (AC) joint disruption, traumatic tendon ruptures, labral lesions, cartilage defects and fractures have to be distinguished from chronic or long-standing pathologies due to recurrent microtrauma, such as overuse bursitis and tendinitis, as well as secondary forms of impingement along with rotator cuff tears and labral lesions. Besides common pathological changes that can be observed in almost all overhead-sports, there are also injuries that are more sport-specific due to the particular load profile in each sport. These injuries are especially common in racquet and throwing sports (e.g. golf, tennis, handball and volleyball) as well as in individual and artistic sports (e.g. swimming, gymnastics, dancing and rowing), contact and extreme sports (e.g. judo, mixed martial arts, bodybuilding, weightlifting, motocross and downhill mountain biking). Knowledge about sport-specific load profiles as well as about the variety of treatment options is crucial for successful treatment of these injuries.
Full text: The diagnostic workup of acute Winter Sports injuries is done by Conventional X Ray, CT and MRI. Chronic injuries as stress reactions are best investigated by Nuclear Medicine procedures: Snow Boarding: In Snow-Boarding chronic injuries are mostly seen as local increased uptake laterally in the lower third of the Fibula of the front leg together with Tibial increase medially in the other leg. Skiing: Chronic Skiing injuries are less asymmetrical and mostly seen on the apex of the patella. Chronic Feet Problems: A different chronic problem is the reduced blood perfusion in the feet if hard, tightened boots are used for longer time by professional ski instructors and racers. Flow difference between the foot in the boot and the other without boot are dramatic as measured by Nuclear Medicine Procedures and MRI. Pulmonary Embolism: Acute pulmonary embolism caused by thrombi originating at the site of constant pressure on the back rim of ski boots is not uncommon in older skiers (seek and you will find), but never seen in the younger group of Snow-Boarders. Copyright (2002) The Australian and New Zealand Society of Nuclear Medicine Inc
In July and August 1999, we investigated the influence of skiing on the catchment hydrology and soil (erosion) in the surroundings of Sölden, Tyrol, Austria. Sölden is a ski village located in the Ötztal valley in between the Ötztaler and Stubaier Alps. During this research, we conducted 122
... page: //medlineplus.gov/ency/patientinstructions/000673.htm Sports physical To use the sharing features on this page, ... routine checkups. Why do you Need a Sports Physical? The sports physical is done to: Find out ...
Iwamoto, Jun; Takeda, Tsuyoshi; Sato, Yoshihiro; Matsumoto, Hideo
Although both gender- and sports-specific injuries exist among athletes, gender differences in the types of injuries caused by sports activities, except for anterior cruciate ligament (ACL) injury and anterior knee pain, are not well established. An observational study with a retrospective case-series design was conducted to investigate gender-specific differences in the types of injuries sustained while engaging in sports activities common to both males and females. We analyzed injuries sustained during sports activities including basketball, volleyball, tennis, skiing, track and field, and swimming, using data on age, sex, sports activities, activity levels, and sports injuries that had been computerized at our sports medicine (orthopedics) clinic. Inclusion criteria were sports activities that had a record of >100 injuries in total and athletes aged sports activity. We determined the absolute number of patients in each category and their percentage (proportion) of our cohort. The proportions of common injuries caused by sports activities were investigated, and gender-specific differences in the types of common injuries caused by sports activities were clarified. The Fisher exact test was used to determine the significance (P gender-specific differences in the types of sports injuries. According to our database, during the 14-year period between October 1992 and December 2006, a total of 2,989 athletes (1,624 males and 1,365 females) aged sports activities described consulted our sports medicine clinic. The most common sports injuries were ACL injury (14.3%) and knee pain (13.7%), followed by ankle sprain (9.4%), lumbar disc disease (7.0%), meniscus injury (5.1%), stress fracture (2.9%), low back pain (2.5%), patellar tendinitis (2.1%), injury of the medial collateral ligament of the knee (2.0%), lumbar spondylolysis (1.7%), and muscle strain (1.5%). Among these 11 types of sports injuries, a significantly higher proportion of females who engaged in basketball
Alexander, Nathalie; Strutzenberger, Gerda; Ameshofer, Lisa Maria; Schwameder, Hermann
Work performance and individual joint contribution to total work are important information for creating training protocols, but were not assessed so far for sloped walking. Therefore, the purpose of this study was to analyze lower limb joint work and joint contribution of the hip, knee and ankle to total lower limb work during sloped walking in a healthy population. Eighteen male participants (27.0±4.7yrs, 1.80±0.05m, 74.5±8.2kg) walked on an instrumented ramp at inclination angles of 0°, ±6°, ±12° and ±18° at 1.1m/s. Kinematic and kinetic data were captured using a motion-capture system (Vicon) and two force plates (AMTI). Joint power curves, joint work (positive, negative, absolute) and each joint's contribution to total lower limb work were analyzed throughout the stance phase using an ANOVA with repeated measures. With increasing inclination positive joint work increased for the ankle and hip joint and in total during uphill walking. Negative joint work increased for each joint and in total work during downhill walking. Absolute work was increased during both uphill (all joints) and downhill (ankle & knee) walking. Knee joint contribution to total negative and absolute work increased during downhill walking while hip and ankle contributions decreased. This study identified, that, when switching from level to a 6° and from 6° to a 12° inclination the gain of individual joint work is more pronounced compared to switching from 12° to an 18° inclination. The results might be used for training recommendations and specific training intervention with respect to sloped walking. Copyright © 2017 Elsevier Ltd. All rights reserved.
Bray, S R; Martin, K A; Widmeyer, W N
Thirty-four youth competitive skiers (mean age = 13.74 years) completed measures of social evaluative concern and competitive anxiety. Consistent with past research, regression analyses showed that cognitive anxiety was related to performance-specific evaluative concerns. However, contrary to current conceptualizations of sport competition anxiety, somatic anxiety was correlated with concerns about evaluation of other non-performance aspects of ski racing. Competitive skiers were most concerned about parents' and friends' evaluations of their performance, and other competitors' and friends' evaluations of their skiing in general. These findings are discussed in relation to the theory and management of sport competition state anxiety.
Full Text Available It was analysed scientific-methodical and specialized literature on adaptive sports: table tennis, basketball, judo, skiing. It is conducted interviews with leading coaches working in the Deaflympic sport. Monitor the training process of elite athletes with hearing impairments, specializing in ski racing. Found that for technical training of athletes use the principle of learning the exercises and improvement from simple to complex with the rote. It was shown the necessity of attracting able-bodied athletes in the training process deflimpiytsev to optimize their technical training. The data obtained allow us to determine the direction of improving the technical skills of this category of athletes.
Full Text Available We describe an original protocol Treating Depression Downhill (TDD that was designed as a specific therapy for depression. Evolutionary theories of depression served as a basis for its development. We discuss the rationale for using evolutionary theory and describe the structure and integrative nature of TDD. We then present an observation on TDD’s application to group therapy of active duty military personnel. In the described sample, TDD demonstrated effectiveness and specificity for depression, differentiating it from anxiety and personality disorders.
Schmikli, Sandor L; Backx, Frank J G; Kemler, Helena J; van Mechelen, Willem
To define target populations for sports injury prevention programs. A computer-assisted telephone survey on sports injuries and sports participation during 2000-2005 using a 3-month recall period. Data obtained from a representative sample of Dutch citizens. Fifty-eight thousand four hundred five Dutch citizens aged older than 3 years. Age, gender, and type of sports were used to distinguish subgroups with a substantial contribution to sports injuries. The absolute number of sports injuries, the incidence of sports injuries per 10,000 hours, the severity, and costs of sports injuries. Sports participation was associated with 1.5 million injuries per year and 10 injuries per 10,000 hours; of these, 50% had to be treated medically. Two-thirds of all medically treated sports injuries were associated with 9 sports (representing 18 subpopulations, all younger than 55 years): outdoor soccer (males 4-54 years and females 4-17 years), indoor soccer (males 18-34 years), tennis (males/females 35-54 years), volleyball (females 18-54 years), field hockey (males 18-34 years and females 4-17 years), running/jogging (males/females 35-54 years), gymnastics (males/females 4-17 years), skiing/snowboarding (males 4-17 years and females 18-34 years), and equestrian sports (females 18-34 years). These groups showed more than average injury rates and covered two-thirds of all direct and indirect costs (euro 400 million). The survey identified the most important (sports-, age-, and gender-specific) target populations for injury prevention programs in the Netherlands. Sports participants aged older than 55 years were excluded from these target groups because of their limited contribution to the total sports injury problem.
Full Text Available Word „marketing“ comes from AngloSaxon linguistic domain and implies in a narrow sense the market. Under marketing, we consider certain process, which should create and solve relations of exchange between manufacturers on one side, and consumers on the other. Discussion about sport marketing implies its theoretical definition and generalization, and then its actual definition in sport environment. Sport marketing belongs to business function of sport organization and represents primaly an economical process of connecting produktion (sport organizations with sportsmen and coaches and consumption (sport and other public. Sport marketing is the reality in sport today, and cannot be observed as fashionabless of capitalistic production. Today is almost impossible for sport organization to make business without its business part called sport marketing if it wants to survive in sport arena.
Virmavirta, M; Komi, P V
In this study, we measured the vertical and horizontal take-off forces, plantar pressures and activation patterns of four muscles (vastus lateralis, gluteus maximus, tibialis anterior, gastrocnemius) in 10 ski jumpers in simulated laboratory conditions when wearing either training shoes or ski jumping boots. We found significant differences in vertical (P boots condition resulted in a smaller displacement in the final position of the following joint angles: ankle angle (P knee angle (P boots condition, significantly more pressure was recorded under the heel (P knee and hip extensors when wearing jumping boots. We conclude that the stiffness of the structure of the jumping boots may result in a forward shift of pressure, thus limiting the effective vertical force. To avoid this pressure shift, the pattern of movement of simulated take-offs should be carefully controlled, particularly when wearing training shoes.
Full Text Available Over 80% of wood extraction operations have been performed by conventional methods in Turkey. Conventional methods include skidding or sliding of logs mainly by man and animal power, which poses problems in terms of technical, economical, environmental, and ergonomic aspects. Skidding wood on plastic chutes has been implemented in limited numbers of logging applications in recent years, and provides important advantages such as reducing environmental damages and minimizing the value and volume loss of transported wood products. In this study, a chute system integrated with a mobile winch was developed for controlled sliding of large diameter logs downhill. In addition, synthetic ropes rather than steel cables were used to pull log products, resulting in a lower weight and more efficient extraction system. The system was tested on a sample wood production operation in Çınarpınar Forest Enterprise Chief of Kahramanmaraş Forest Enterprise Directorate. In the study, productivity analysis of chute system was performed and its ecological impacts were evaluated. During controlled sliding of logs downhill, the highest productivity (10.01 m3/hour was reached in the fourth chute system characterized as 36 m in length and 70% ground slope. One of the main factors that affected the productivity of chute system was the controlled sliding time of the logs. It was found that residual stand damage was very limited during controlled sliding operations.
Jung, Alexander; Staat, Manfred; Müller, Wolfram
In V-style ski jumping, aerodynamic forces are predominant performance factors and athletes have to solve difficult optimization problems in parts of a second in order to obtain their jump length maximum and to keep the flight stable. Here, a comprehensive set of wind tunnel data was used for optimization studies based on Pontryagin's minimum principle with both the angle of attack α and the body-ski angle β as controls. Various combinations of the constraints αmax and βmin(t) were analyzed in order to compare different optimization strategies. For the computer simulation studies, the Olympic hill profiles in Esto-Sadok, Russia (HS 106m, HS 140m), and in Harrachov, Czech Republic, host of the Ski Flying World Championships 2014 (HS 205m) were used. It is of high importance for ski jumping practice that various aerodynamic strategies, i.e. combinations of α- and β-time courses, can lead to similar jump lengths which enables athletes to win competitions using individual aerodynamic strategies. Optimization results also show that aerodynamic behavior has to be different at different hill sizes (HS). Optimized time courses of α and β using reduced drag and lift areas in order to mimic recent equipment regulations differed only in a negligible way. This indicates that optimization results presented here are not very sensitive to minor changes of the aerodynamic equipment features when similar jump length are obtained by using adequately higher in-run velocities. However, wind tunnel measurements with athletes including take-off and transition to stabilized flight, flight, and landing behavior would enable a more detailed understanding of individual flight style optimization. © 2013 Published by Elsevier Ltd.
Pellegrini, B; Zoppirolli, C; Boccia, G; Bortolan, L; Schena, F
We investigated the relationships between the biomechanics of the double poling (DP) technique in cross-country skiing, its economy, and athletes' skill. To this aim, skiers' motion has been factorized into components through principal component analysis (PCA). Eight high-level (HL) and eight regional level (RL) male cross-country skiers performed a 5-minute submaximal DP trial while roller skiing on a treadmill at 14 km h -1 and 2° incline. Whole-body kinematics was recorded with a motion capture system. PCA was applied to markers coordinates to extract principal movements (PM k ), which were ranked by their variance. Energy cost (EC) of locomotion was calculated from ergospirometric measurements. Results showed that 96.7%±0.6% of total skiing pattern variance can be described with the first three PM k. (Shoulder and trunk flexion-extension are described PM 1 and PM 2 and elbow flexion-extension are mainly represented in PM 2 and PM 3. The variance of further components, consisting of residual movements (eg, slow postural changes or high-frequency vibrations), was greater for the RL than the HL skiers (4.0%±0.5% vs 2.6%±0.3%; P<.001) and was positively correlated with EC (R 2 =.646; P<.001). PCA permitted to describe the biomechanics of the DP technique through a limited set of principal movements. Skiing skills and economy appeared to be related to a skier's ability to simplify movement complexity, suggesting that an efficient skier is better able to reduce superfluous movement components during DP. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Finch, C F; Kelsall, H L
This article presents a critical review of the extent to which alpine ski bindings and their adjustment have been formally demonstrated to prevent injuries. It considers a range of evidence, from anecdotal evidence and informed opinion to biomechanical studies, testing of equipment, epidemiological studies and controlled field evaluations. A total of 15 published studies examining the effectiveness of bindings and their adjustment were identified. All of these included anecdotal or informed opinion, and all but one focused on equipment design. Seven studies involved the testing of bindings or binding prototypes, 2 studies presented biomechanical models of the forces involved in binding operation, 6 reported an epidemiological evaluation of ski bindings and 2 considered skiers' behaviours towards binding adjustment. Some of the reviewed articles relate to the study of the biomechanics of ski bindings and their release in response to various loads and loading patterns. Other studies examined the contribution of bindings and binding-release to lower extremity, equipment-related injuries, the effect of various methods of binding adjustment on injury risk and the determinants of skiers' behaviour relating to professional binding adjustment. Most of the evidence suggests that currently used bindings are insufficient for the multidirectional release required to reduce the risk of injury to the lower limb, especially at the knee. This evidence suggests that further technical developments and innovations are required. The standard of the manufacture of bindings and boots also needs to be considered. The optimal adjustment of bindings using a testing device has been shown to be associated with a reduced risk of lower extremity injury. Generally, however, the adjustment of bindings has been shown to be inadequate, especially for children's bindings. Recommendations for further research, development and implementation with respect to ski binding and their adjustment are given
REPORT & PERIOD COVERED ADDITIONAL SMOOTH AND ROUGH WATER TRIALS OF FINAL SKI- CAT S. PERFORMING ORO. REPORT NUMSER 7. AUTHOR() I. CONTRACT OR GRANT NUMUr...Identif by bloc membe) ’ " -Further tests of SKI- CAT were made in smooth and rough water. Smooth water results confirmed the performance results of...reductions in the accelerations and motions of SKI- CAT over against the head seasreut DD , +A ,3 1473 EDITION OF I NOVS IS OBSOLETE UNCIbSJFIED SIME 0102-014
Ekmekci, Ridvan; Ekmekçi, Aytul Yeter
Abstract Marketing which is entered to almost our whole life, now more than goods and services, became an important concept of ideas, persons, institutions, events, and facilities. As a main activities of business co. marketing has an important place in sports industry. Recently, the development of special sport marketing strategies and the presentation of sport goods and services to consumers are gaining importance. Efforts of increasing income of sport clubs, because of sport organization...
Injuries caused by ski jumping have been poorly investigated. Among approximately 2,200 licensed jumpers in Norway, there occurred at least 12 injuries with a permanent medical disability of greater than or equal to 10%. The risk of being seriously injured is approximately 5% in a 5 year period (1977 to 1981); it is higher in the age group 15 to 17 years. Seven injuries were very serious [four central nervous system (CNS) lesions, two leg amputations, and one blindness of one eye], and five were less serious (sequelae to fractures of the lower extremities). The first jump of the day is particularly dangerous, and so is the beginning and end of the season. It seems dangerous to use more than one standard heel block. Poor preparation of the jump may have contributed to the accidents. Based on the findings, several prophylactic measures are suggested.
Indoor skiing halls are conventionally operated at low temperatures and with either crushed ice as snow substitute or snow made from freezing water in cold air. Both systems have a high energy demand for air cooling, floor freezing and consequently snow harvest. At the same time the snow at the top...... floor cooling/freezing and insulation become obsolete, significant savings in piping and building costs can be achieved. Due to the much higher evaporating temperature for the refrigeration system, the energy demand is kept low. Since the same equipment is used for both snowmaking and air cooling......, the running time of the equipment is high, resulting in a better economy. Using Binary Snow, with its unique qualities such as fluffy, crisp, white and ¿ since made daily ¿ "fresh and hygienic", offers great advantages in operating costs, investment costs and quality....
Nunner, T.; Sidla, O.; Paar, G.; Nauschnegg, B.
Ski jumping has continuously raised major public interest since the early 70s of the last century, mainly in Europe and Japan. The sport undergoes high-level analysis and development, among others, based on biodynamic measurements during the take-off and flight phase of the jumper. We report on a vision-based solution for such measurements that provides a full 3D trajectory of unique points on the jumper's shape. During the jump synchronized stereo images are taken by a calibrated camera system in video rate. Using methods stemming from video surveillance, the jumper is detected and localized in the individual stereo images, and learning-based deformable shape analysis identifies the jumper's silhouette. The 3D reconstruction of the trajectory takes place on standard stereo forward intersection of distinct shape points, such as helmet top or heel. In the reported study, the measurements are being verified by an independent GPS measurement mounted on top of the Jumper's helmet, synchronized to the timing of camera exposures. Preliminary estimations report an accuracy of +/-20 cm in 30 Hz imaging frequency within 40m trajectory. The system is ready for fully-automatic on-line application on ski-jumping sites that allow stereo camera views with an approximate base-distance ratio of 1:3 within the entire area of investigation.
François, Hugues; Spandre, Pierre; Morin, Samuel; George-Marcelpoil, Emmanuelle; Lafaysse, Matthieu; Lejeune, Yves
In order to face climate change, meteorological variability and the recurrent lack of natural snow on the ground, ski resorts adaptation often rely on technical responses. Indeed, since the occurrence of episodes with insufficient snowfalls in the early 1990's, snowmaking has become an ordinary practice of snow management, comparable to grooming, and contributes to optimise the operation of ski resorts. It also participates to the growth of investments and is associated with significant operating costs, and thus represents a new source of vulnerability. The assessment of the actual effects of snowmaking and of snow management practices in general is a real concern for the future of the ski industry. The principal model use to simulate snow conditions in resorts, Ski Sim, has also been moving this way. Its developers introduced an artificial input of snow on ski area to complete natural snowfalls and considered different organisations of ski lifts (lower and upper zones). However the use of a degree-day model prevents them to consider the specific properties of artificial snow and the impact of grooming on the snowpack. A first proof of concept in the French Alps has shown the feasibility and the interest to cross the geographic model of ski areas and the output of the physically-based reanalysis of snow conditions SAFRAN - Crocus (François et al., CRST 2014). Since these initial developments, several ways have been explored to refine our model. A new model of ski areas has been developed. Our representation is now based on gravity derived from a DEM and ski lift localisation. A survey about snow management practices also allowed us to define criteria in order to model snowmaking areas given ski areas properties and tourism infrastructures localisation. We also suggest to revisit the assessment of ski resort viability based on the "one hundred days rule" based on natural snow depth only. Indeed, the impact of snow management must be considered so as to propose
Federiuk, C S; Mann, N C
To determine the types of injuries associated with telemark skiing and the effects of ability level, equipment, and terrain. A survey was mailed to a sample of North American telemark skiers. Completed surveys were returned by 548 telemarkers (response rate = 74.5%). The mean age was 42.7 (+/- 9.3) years, and 69% were male. A total of 439 injury events resulted in 494 body injuries, reported by 285 skiers (52%). Lower-extremity injuries (n = 231) were more frequent than upper-extremity injuries (n = 187). Knee injuries were most common with 128 cases, followed by 80 thumb, 66 shoulder, and 44 ankle injuries. Surgery was required in 39 cases. Skiers suffering thumb injuries with sequela lasting greater than 3 months were 10.1 times less likely to have sought medical attention than skiers with other long-term injuries (p boot type and overall knee or ankle injury, but risk of severe ankle injury was increased in leather boots compared to plastic (OR = 8.0, CI = 1.05, 60.59). Release bindings were used by 27.9% of all skiers but were in use in only 18.7% of injury events, suggesting that release plates have a protective effect against injury (OR = 0.59, p knee, thumb, shoulder, and ankle are most frequently injured telemark skiing. Injuries are more likely to occur at lift-served areas than in the backcountry. Thumb injuries are often ignored and may result in long-term sequela. Ankle injuries appear more severe in leather boots. Release bindings appear protective against injury, but they often do not release.
Chan, Christie Wl; Eng, Janice J; Tator, Charles H; Krassioukov, Andrei
Despite the recognition of sports as a significant contributor in the etiology of spinal cord injury (SCI), no studies have systematically explored the epidemiology of SCI caused by sports. This paper aims to give a systematic overview of the epidemiology of sport-related spinal cord injury around the world. A systematic review was conducted to identify published literature reporting the epidemiology of SCI caused by sports. The literature search was conducted in MEDLINE/PubMed, CINAHL, EMBASE, PsycINFO and Sportdiscus with date limits 1980 through to July 2015. Data from 54 studies covering 25 countries was extracted and collated. Important findings include identification of 6 countries in which sports accounts for over 13% of SCI (highest to lowest: Russia, Fiji, New Zealand, Iceland, France and Canada); individual sports with high risk for SCI (diving, skiing, rugby, and horseback riding); and the most common level of injury for various sports (almost entirely cervical for hockey, skiing, diving and American football, while over half of horseback riding and snowboarding injuries are thoracic or lumbosacral). This paper identifies countries and sports with higher rates of sport-related SCIs where implementation of prevention programs and reporting systems to track SCI epidemiology may be helpful, and highlights gaps in our current knowledge for further investigation. The comparison of SCI occurrence for each sport across countries, as well as examination of the specific characteristics of SCI incurred for individual sports will assist in directing efforts for prevention.
Ski areas represent a unique opportunity to develop innovative energy management practices in an industrial setting. Through a unique synergy of onsite generation, preferably by renewable sources and innovative technologies, and the energy storage potential of exis...
Full Text Available The environmental impacts in Serbian ski areas are very strong, leading to landscape degradation and functionality losses. Construction or improvement works cause serious destruction of topsoil and native vegetation. Some activities enhance erosion production and sediment yield: clear cuttings; trunk transport down the slope; road construction and large excavations. Also, lack of erosion control works in ski areas, especially between April and October, result in various forms of land degradation such as furrows, gullies, landslides, or debris from rock weathering. The consequences of mismanagement in ski areas are noticeable in downstream sections of river beds, causing floods and bed-load deposition. Planning and designing activities, with the application of technical and biotechnical erosion control structures, through the concept of restoration, are necessary measures in the protection of ski areas.
Kurpiers, Nicolas; McAlpine, Paul R; Kersting, Uwe G
The purpose of this study was to examine the effects of using a force measurement device on riding technique in mogul skiing. A mock-up version of such a device was positioned between ski boot and binding. Data on three-dimensional kinematics and perception were collected for eight subjects skiing down a mogul course. Parameters analysed were knee angle, side and forward lean of the trunk and hip, and the path of the body's centre of mass. A perception questionnaire was used on selective aspects to assess the skiers' perception of the performances. Perception ratings showed no significant detrimental effects. All assessed components showed a trend of improvement from the first to last run, thus suggesting familiarisation was achieved. Kinematic analysis revealed that no significant alterations occurred. In conclusion, it is intended to utilise a functional force plate similar to the one presented by Kiefmann et al. (2006) for future studies in freestyle skiing.
Jakse, G; Madersbacher, H
During 1964-1974 112 injuries of the urogenital tract caused by winter sports were treated at the University Hospital Innsbruck, Department of Urology. Eighty-eight patients suffered skiing injuries, 20 tobogganing injuries, and one injury each was caused by ski jumping and bobsleighing accidents, two traumas resulted from a fall from a chair lift. On the basis of typical case reports the most common types of trauma of the urogenital tract are demonstrated and the basic mechanisms of the accidents are discussed. Particular attention is paid to the obvious increase of lesions of the external genitalia and the urethra in the last few years caused by the so-called spinning ski, as well as the frequency of kidney traumas, especially in winters with little snow. Tobogganing accidents caused injuries to the kidneys as well as to bladder and urethra. In contrast to traumas caused by skiing, tobogganing injuries were mostly multiple. Analysis of patients records shows an increase of these injuries, which were really not typical for winter sports. The possible reasons as well as their prevention are discussed.
The Master's Thesis analyses and evaluates the conditions for the Ski & Snowboard School Lúčky development in the Jasná Nízke Tatry ski resort as well as it illustrates specific steps and actions in the realistic business plan. Firstly, it introduces theoretical background of feasibility analysis, business model, and the business plan focusing on the importance and structure of each topic. Secondly, the thesis portrays the results of an empirical research conducted on the target audience that...
Kröll, Josef; Müller, Erich; Seifert, John G.; Wakeling, James M.
During a day of skiing thousands of repeated contractions take place. Previous research on prolonged recreational alpine skiing show that physiological changes occur and hence some level of fatigue is inevitable. In the present paper the effect of prolonged skiing on the recruitment and coordination of the muscle activity was investigated. Six subjects performed 24 standardized runs. Muscle activity during the first two (PREskiing) and the last two (POSTskiing) runs was measured from the vastus lateralis (VL) and rectus femoris (RF) using EMG and quantified using wavelet and principal component analysis. The frequency content of the EMG signal shifted in seven out of eight cases significantly towards lower frequencies with highest effects observed for RF on outside leg. A significant pronounced outside leg loading occurred during POSTskiing and the timing of muscle activity peaks occurred more towards turn completion. Specific EMG frequency changes were observed at certain time points throughout the time windows and not over the whole double turn. It is suggested that general muscular fatigue, where additional specific muscle fibers have to be recruited due to the reduced power output of other fibers did not occur. The EMG frequency decrease and intensity changes for RF and VL are caused by altered timing (coordination) within the turn towards a most likely more uncontrolled skiing technique. Hence, these data provide evidence to suggest recreational skiers alter their skiing technique before a potential change in muscle fiber recruitment occurs. Key points The frequency content of the EMG signal shifted in seven out of eight cases significantly towards lower frequencies with highest effects observed for RF. General muscular fatigue, where additional specific fibers have to be recruited due to the reduced power output of other fibers, did not occur. A modified skiing style towards a less functional and hence more uncontrolled skiing technique seems to be a key
In this paper, I review biomechanics research in ski jumping with a specific focus on publications presented between 1991 and 2006 on performance enhancement, limiting factors of the take-off, specific training and conditioning, aerodynamics, and safety. The first section presents a brief description of ski jumping phases (in-run, take-off, early flight, stable flight, and landing) regarding the biomechanical and functional fundamentals. The most important and frequently used biomechanical methods in ski jumping (kinematics, ground reaction force analyses, muscle activation patterns, aerodynamics) are summarized in the second section. The third section focuses on ski jumping articles and research findings published after the establishment of the V-technique in 1991, as the introduction of this technique has had a major influence on performance enhancement, ski jumping regulations, and the construction of hill profiles. The final section proposes topics for future research in the biomechanics of ski jumping, including: take-off and early flight and the relative roles of vertical velocity and forward somersaulting angular momentum; optimal jumping patterns utilizing the capabilities of individual athletes; development of kinematic and kinetic feedback systems for hill jumps; comparisons of simulated and hill jumps; effect of equipment modifications on performance and safety enhancement.
Janurová, Eva; Janura, Miroslav; Cabell, Lee; Svoboda, Zdeněk; Vařeka, Ivan; Elfmark, Milan
The concept of kinematic chains has been systematically applied to biological systems since the 1950s. The course of a ski jump can be characterized as a change between closed and open kinematic chains. The purpose of this study was to determine a relationship between adjacent segments within the ski jumper's body's kinematic chain during the in-run phase of the ski jump. The in-run positions of 267 elite male ski jumpers who participated in the FIS World Cup events in Innsbruck, Austria, between 1992 and 2001 were analyzed (656 jumps). Two-dimensional (2-D) kinematic data were collected from the bodies of the subjects. Relationships between adjacent segments of the kinematic chain in the ski jumper's body at the in-run position are greater nearer the chain's ground contact. The coefficient of determination between the ankle and knee joint angles is 0.67. Changes in the segments' positions in the kinematic chain of the ski jumper's body are stable during longitudinal assessment. Changes in shank and thigh positions, in the sense of increase or decrease, are the same.
Ristić, Ratko; Kašanin-Grubin, Milica; Radić, Boris; Nikić, Zoran; Vasiljević, Nevena
The environmental impacts of ski resorts in the Balkan region are great and can lead to landscape degradation and loss of land functionality. In this study, we present an example of the negative effects of human activities at the Stara Planina ski resort in southeastern Serbia. The objective of this study is detailed analysis of the characteristics of environmental impacts at the Stara Planina. The management of the ski area and ski slope development caused severe degradation of topsoil and native vegetation. The morphological characteristics of the area, lithological properties of the exposed material and climate conditions resulted in various geomorphic impacts, including rills, deep gullies, solifluctions and debris from rock weathering. Significant changes in land usage altered hydrological conditions, resulting in more frequent torrential floods in the downstream sections of the Zubska River and increased the sediment yield. Environmental impacts were analyzed in the immediate and wider zones of the ski resort in accordance with the specific topography and visual exposure. The restoration and erosion control measures have stopped degradation processes and helped to rehabilitate the appearance and functions of the landscape. The results show the importance of considering lithological (the type and characteristics of minerals present) and hydrological (precipitation, water storage capacity of soil, runoff) factors under the conditions of significant changes in land usage. The results of this investigation can contribute to the improvement of planning processes and the implementation of development projects in ski areas.
ASCERI is the Association of the Sports Communities of the European Research Institutes and aims to contribute to a united Europe through regular sports meetings, bringing together members of public Research Institutes at European level. The Association's members come from over 42 Research Institutes spanning 15 countries. The association was born from the German "Kernforschungszentrum Karlsruhe" (KfK) football team who had the idea to play against other teams from institutes also involved in nuclear research. Therefore, six teams from different German centres were invited to take part in a "Reaktoren Fußballturnier" in Karlsruhe on 2 July 1966. Ever since, The Winter-ATOMIADE has taken place every three years and alternating with the Summer-ATOMIADE and a Mini Atomiade in between with numerous sports and leisure activities including football, skiing, golf, athletics, tennis, volleyball to name a few. CERN has been a regular participant ...
Ski jumping puts high demands on the athlete's ability to control posture and movement. The athlete has to solve extremely difficult optimization problems. These implicit decisions and the resulting control manoeuvres can be understood by means of computer simulations. Computer simulations based on wind tunnel input data can identify the determinants for high performance and answer many questions of training methods, safety and health, role of weight, fairness, optimized hill design, sport development, and changes to the regulations. Each of the performance determinants has to be seen in the context of all others in order to understand its importance; the predominant factors are: high in-run velocity, high momentum perpendicular to the ramp at take-off due to the jump and the lift force, accurate timing of the take-off with respect to the ramp edge, appropriate angular momentum at take-off in order to obtain an aerodynamically advantageous and stable flight position as soon as possible, choice of advantageous body and equipment configurations during the entire flight in order to obtain optimum lift and drag values, and the ability to control the flight stability. Wind blowing up the hill increases the jump length dramatically and decreases the landing velocity, which eases the landing, and vice versa for wind from behind. Improvements to reduce unfairness due to changing wind are urgently needed. The current practice of the judges to reduce the score when the athlete has to perform body movements in order to counteract dangerous gusts is irrational. The athletes should rather be rewarded and not punished for their ability to handle such dangerous situations. For the quantification of underweight it is suggested to use the mass index: MI=0.28 m/s2 (where m is the jumper mass and s is the sitting height), which indirectly considers the individual leg length. The MI formula is similar to the body mass index (BMI) formula: the height is replaced by the sitting height s
Full Text Available Lisa Müller,1 Carolin Hildebrandt,1,2 Erich Müller,3 Renate Oberhoffer,2 Christian Raschner1 1Department of Sport Science, University of Innsbruck, Innsbruck, Austria; 2Department of Sport and Health Science, Preventative Pediatrics, Technical University of Munich, Munich, Germany; 3Department of Sport Science and Kinesiology, University of Salzburg, Salzburg, Austria Background: Studies on injuries and illnesses involving youth ski racers younger than 15 years are lacking in the literature. The aim of this study was prospectively to assess the incidence, prevalence, and severity of traumatic and overuse injuries, as well as illnesses of elite youth ski racers with regard to sex, biological maturity status, and relative age.Subjects and methods: A prospective, longitudinal cohort design was used to monitor the anthropometrics, training characteristics, traumatic and overuse injuries, and illnesses of 82 elite youth ski racers (51 males, 31 females, age 9–14 years over 2 consecutive years. The exact training exposure (skiing and athletic was recorded. Relative age and estimated biological maturity status were assessed.Results: Relatively low injury incidence or prevalence (traumatic, 0.86/1,000 hours of training; overuse, 0.28/1,000 hours and comparably high illness prevalence (2.4/athlete were reported. The knee was the most commonly affected body part (traumatic injuries 36.5%, overuse injuries 82%. A high number of bone fractures were revealed (46%, while no stress fractures occurred; 66% of the illnesses were respiratory tract infections. No differences were found between males and females, the differing maturity groups, or relative age quartiles. Early-maturing athletes had comparably low traumatic and overuse-injury rates. Relatively younger athletes had low traumatic injury rates.Conclusion: The injury-prevention measures implemented in the training process of youth ski racers seem to contribute to a low incidence of injury. Biological
Pablo C. B. Lollo
Full Text Available Running on a horizontal plane is known to increase the concentration of the stress biomarker heat-shock protein (HSP, but no comparison of the expression of HSP70 has yet been established between the uphill (predominantly concentric and downhill (predominantly eccentric muscle contractions exercise. The objective of the study was to investigate the relationships between eccentric and concentric contractions on the HSP70 response of the lung, kidney, gastrocnemius, soleus and heart. Twenty-four male Wistar weanling rats were divided into four groups: non-exercised and three different grades of treadmill exercise groups: horizontal, uphill (+7% and downhill (-7% of inclination. At the optimal time-point of six hours after the exercise, serum uric acid, creatine kinase (CK and lactate dehydrogenase (LDH were determined by standard methods and HSP70 by the Western blot analysis. HSP70 responds differently to different types of running. For kidney, heart, soleus and gastrocnemius, the HSP70 expression increased, 230, 180, 150 and 120% respectively of the reference (horizontal. When the contraction was concentric (uphill and compared to downhill the increase in response of HSP70 was greater in 80% for kidney, 75% for gastrocnemius, 60% for soleus and 280% for the heart. Uric acid was about 50% higher (0.64 ± 0.03 mg·dL-1 in the uphill group as compared to the horizontal or downhill groups. Similarly, the activities of serum CK and LDH were both 100% greater for both the uphill and downhill groups as compared to the horizontal group (2383 ± 253 and 647.00 ± 73 U/L, respectively. The responsiveness of HSP70 appeared to be quite different depending on the type of tissue, suggesting that the impact of exercise was not restricted to the muscles, but extended to the kidney tissue. The uphill exercise increases HSP70 beyond the eccentric type and the horizontal running was a lower HSP70 responsive stimulus
Playing sports can be fun, but it can also be dangerous if you are not careful. You can help ... you are healthy before you start playing your sport Wearing the right shoes, gear, and equipment Drinking ...
... sometimes you can injure yourself when you play sports or exercise. Accidents, poor training practices, or improper ... can also lead to injuries. The most common sports injuries are Sprains and strains Knee injuries Swollen ...
Full Text Available Introduction: Decades of research support the theory that when there are sports competitions the question of what to eat and drink in order to enhance sport performance. Nutrition is one of the most important factors in achieving top performance athletes. According to most studies conducted in the world's top athletes receive information from their coaches when it comes to sports nutrition, especially of the coaches involved in fitness training. (Burns, Schiller, Merrick & Wolf, 2004.The aim of this study was to determine the knowledge of sports nutrition in sports coaching. Mthods: The sample was composed of 30 licensed coaches from Montenegro (football, handball, basketball, volleyball, athletics and tennis. Knowledge of sports nutrition was tested by means of a standardized questionnaire. The questionnaire was designed to determine the knowledge manager on sports nutrition, the ingredients that are necessary in order to provide a sufficient amount of energy to training and competition, the dietary supplements, meal prior to the competition as well as dehydration and rehydration during training and competition. The survey was anonymous. The data were analyzed by statistical methods, using the statistical software STATISTICA for WINDOWS. Results: According to the results as a whole, it can be concluded that the trainer's knowledge of sports nutrition at a satisfactory level. Out of 600 responses was achieved 469 correct answers, or 78.1%. However, when looking at individual responses then satisfaction with the relative high percentage loss since the observed large gaps on very important issues related to sports nutrition. Discussion: By analyzing and comparing research results (Matkovic, Prince & Cigrovski, 2006 that in a sample of 56 coaches basketball and skiing, received 77.8% of correct answers and insight into the results of our study, it is clear that the results of the approximate value of both work, which is an indicator of quality
Full Text Available The Author presents her first Italian translation of Anatol Stern’s article (excerpted from his monograph on Polish Avantgarde Rebelled Poetry. Sketches on Interwar Period Poetry [1964, 2nd issue 1970] about another prominent initiator and ideologist of Polish futurism, Bruno Jasieński. After the Thaw, Stern first contributed to Jasieński’s rehabilitation, publishing his poetry and the novel I burn Paris and writing several essays about his work. The article presented also offers a choice of translated fragments of Jasieński’s poetry, just a few known in Italy, and an artistic profile of Stern.
Sport supplementation is essential for athletes performance and achievements. The well balanced and structured supplementation is a challenge for sport medicine because must be done a balance between potential benefits and potential risks (anti-doping rule violations and others). In this review are structured the most used categories sport supplementations. Nutritional supplements used in sport could be divided in some main categories like: amino acids, vitamins, proteins and antioxidants. Fo...
Omer Špirtović; Danilo Aćimović; Ahmet Međedović; Zoran Bogdanović
Word „marketing“ comes from AngloSaxon linguistic domain and implies in a narrow sense the market. Under marketing, we consider certain process, which should create and solve relations of exchange between manufacturers on one side, and consumers on the other. Discussion about sport marketing implies its theoretical definition and generalization, and then its actual definition in sport environment. Sport marketing belongs to business function of sport organization and represents primaly an eco...
Sports play a very important and diverse role in the present-day global culture. On the occasion of the 105th anniversary of Coubertin’s Ode we would like to wish sports to return to the main words of the Ode and to correspond with them: “Oh sport, you are the peace”.
Full Text Available Substantial inter-individual variations in exercise economy exist even in highly trained endurance athletes. The variation is believed to be determined partly by intrinsic factors. Therefore, in the present study, we compared exercise economy in V2-skating, double poling and uphill running. Ten highly trained male cross-country skiers (23 ± 3 years, 180 ± 6 cm, 75 ± 8 kg, VO2peak running: 76.3 ± 5.6 mL•kg-1•min-1 participated in the study. Exercise economy and VO2peak during treadmill running, ski skating (V2 technique and double poling were compared based on correlation analysis with subsequent criteria for interpreting the magnitude of correlation (r. There was a very large correlation in exercise economy between V2-skating and double poling (r = 0.81 and a large correlation between V2-skating and running (r = 0.53 and double poling and running (r = 0.58. There were trivial to moderate correlations between exercise economy and VO2peak (r = 0.00-0.23, cycle rate (r = 0.03-0.46, body mass (r = -0.09-0.46 and body height (r = 0.11-0.36. In conclusion, the inter-individual variation in exercise economy could only moderately be explained by differences in VO2peak, body mass and body height and therefore we suggest that other intrinsic factors contribute to the variation in exercise economy between highly trained subjects.
Braunisch, Veronika; Patthey, Patrick; Arlettaz, Raphaël
Outdoor winter recreation exerts an increasing pressure upon mountain ecosystems, with unpredictable, free-ranging activities (e.g., ski mountaineering, snowboarding, and snowshoeing) representing a major source of stress for wildlife. Mitigating anthropogenic disturbance requires the spatially explicit prediction of the interference between the activities of humans and wildlife. We applied spatial modeling to localize conflict zones between wintering Black Grouse (Tetrao tetrix), a declining species of Alpine timberline ecosystems, and two free-ranging winter sports (off-piste skiing [including snow-boarding] and snowshoeing). Track data (snow-sports and birds' traces) obtained from aerial photographs taken over a 585-km transect running along the timberline, implemented within a maximum entropy model, were used to predict the occurrence of snow sports and Black Grouse as a function of landscape characteristics. By modeling Black Grouse presence in the theoretical absence of free-ranging activities and ski infrastructure, we first estimated the amount of habitat reduction caused by these two factors. The models were then extrapolated to the altitudinal range occupied by Black Grouse, while the spatial extent and intensity of potential conflict were assessed by calculating the probability of human-wildlife co-occurrence. The two snow-sports showed different distribution patterns. Skiers' occurrence was mainly determined by ski-lift presence and a smooth terrain, while snowshoers' occurrence was linked to hiking or skiing routes and moderate slopes. Wintering Black Grouse avoided ski lifts and areas frequented by free-ranging snow sports. According to the models, Black Grouse have faced a substantial reduction of suitable wintering habitat along the timberline transect: 12% due to ski infrastructure and another 16% when adding free-ranging activities. Extrapolating the models over the whole study area results in an overall habitat loss due to ski infrastructure of
Xiao, Xiao; Hedman, Jonas; Tan, Felix Ter Chian
evolution, as digital technologies are increasingly entrenched in a wide range of sporting activities and for applications beyond mere performance enhancement. Despite such trends, research on sports digitalization in the IS discipline is surprisingly still nascent. This paper aims at establishing...... a discourse on sports digitalization within the discipline. Toward this, we first provide an understanding of the institutional characteristics of the sports industry, establishing its theoretical importance and relevance in our discipline; second, we reveal the latest trends of digitalization in the sports...
Andersson, Erik; Pellegrini, Barbara; Sandbakk, Oyvind; Stüggl, Thomas; Holmberg, Hans-Christer
Cycle and force characteristics were examined in 11 elite male cross-country skiers using the diagonal stride technique while skiing uphill (7.5°) on snow at moderate (3.5 ± 0.3 m/s), high (4.5 ± 0.4 m/s), and maximal (5.6 ± 0.6 m/s) velocities. Video analysis (50 Hz) was combined with plantar (leg) force (100 Hz), pole force (1,500 Hz), and photocell measurements. Both cycle rate and cycle length increased from moderate to high velocity, while cycle rate increased and cycle length decreased at maximal compared to high velocity. The kick time decreased 26% from moderate to maximal velocity, reaching 0.14 s at maximal. The relative kick and gliding times were only altered at maximal velocity, where these were longer and shorter, respectively. The rate of force development increased with higher velocity. At maximal velocity, sprint-specialists were 14% faster than distance-specialists due to greater cycle rate, peak leg force, and rate of leg force development. In conclusion, large peak leg forces were applied rapidly across all velocities and the shorter relative gliding and longer relative kick phases at maximal velocity allow maintenance of kick duration for force generation. These results emphasise the importance of rapid leg force generation in diagonal skiing.
Vodičar, Janez; Coh, Milan; Jošt, Bojan
The purpose of our research was to establish the variability of correlation between the length of the jumps and selected multi-item kinematic variables (n=9) in the early flight phase technique of ski jumping. This study was conducted on a sample of elite Slovenian ski jumpers (N=29) who participated in the experiment on a jumping hill in Hinterzarten, Germany (HS95m) on the 20(th) of August, 2008. The highest and most significant correlations (p=0.01) with the length of the ski jump were found in the multi-item variable height of flying, which was also expressed with the highest level of stability of the explained total variance (TV) on the first factor (TV=69.13%). The most important characteristic of the aerodynamic aspect of early flight was the variable angle between the body chord and the horizontal axis with significantly high correlations (pjump. Only two more variables, the angle between the upper body and the horizontal plane (TV=53.69%), and the angle between left ski and left leg (TV=50.13%), had an explained common variance on the first factor greater than 50% of total variance. The results indicated that some kinematic parameters of ski jumping early flight technique were more important for success considering the length of the jump.
Full Text Available The article discusses the motif of filial love of distinctive romantic poet, the author of Nie-Boska Komedia, Zygmunt Krasiński. The unusual fascination by the paternal will mainly shown in letters written by the son to his father, as Zygmunt Krasiński spent most of his life abroad and from there he maintained a continuous correspondence with his father, general Wincenty Krasiński, the deputy and then the chief warden of the Polish Kingdom. The poet’s father, the former Napoleonic general, chose the service for the new leader – the Russian tsar. That was something irreconcilable for the feeble son who kept using the services of bathing sanatoria and maintained epistolary discussion with the beloved father. The ideological conflict usually concluded in admitting the righteousness to the “beloved daddy” in particular matters. That, however, caused real ethical dilemmas for the sensitive condescending youth. The unusually rich correspondence of Zygmunt Krasiński is undoubtedly a precious contribution to nineteenth century thought, and also into family and existential aspects of the two uncommon men – Zygmunt and Wincenty Krasiński.
Full Text Available During a day of skiing thousands of repeated contractions take place. Previous research on prolonged recreational alpine skiing show that physiological changes occur and hence some level of fatigue is inevitable. In the present paper the effect of prolonged skiing on the recruitment and coordination of the muscle activity was investigated. Six subjects performed 24 standardized runs. Muscle activity during the first two (PREskiing and the last two (POSTskiing runs was measured from the vastus lateralis (VL and rectus femoris (RF using EMG and quantified using wavelet and principal component analysis. The frequency content of the EMG signal shifted in seven out of eight cases significantly towards lower frequencies with highest effects observed for RF on outside leg. A significant pronounced outside leg loading occurred during POSTskiing and the timing of muscle activity peaks occurred more towards turn completion. Specific EMG frequency changes were observed at certain time points throughout the time windows and not over the whole double turn. It is suggested that general muscular fatigue, where additional specific muscle fibers have to be recruited due to the reduced power output of other fibers did not occur. The EMG frequency decrease and intensity changes for RF and VL are caused by altered timing (coordination within the turn towards a most likely more uncontrolled skiing technique. Hence, these data provide evidence to suggest recreational skiers alter their skiing technique before a potential change in muscle fiber recruitment occurs
Soligard, Torbjørn; Steffen, Kathrin; Palmer-Green, Debbie; Aubry, Mark; Grant, Marie-Elaine; Meeuwisse, Willem; Mountjoy, Margo; Budgett, Richard; Engebretsen, Lars
Systematic surveillance of injuries and illnesses is the foundation for developing preventive measures in sport. To analyse the injuries and illnesses that occurred during the XXII Olympic Winter Games, held in Sochi in 2014. We recorded the daily occurrence (or non-occurrence) of injuries and illnesses (1) through the reporting of all National Olympic Committee (NOC) medical teams and (2) in the polyclinic and medical venues by the Sochi 2014 medical staff. NOC and Sochi 2014 medical staff reported 391 injuries and 249 illnesses among 2780 athletes from 88 NOCs, equalling incidences of 14 injuries and 8.9 illnesses per 100 athletes over an 18-day period of time. Altogether, 12% and 8% of the athletes incurred at least one injury or illness, respectively. The percentage of athletes injured was highest in aerial skiing, snowboard slopestyle, snowboard cross, slopestyle skiing, halfpipe skiing, moguls skiing, alpine skiing, and snowboard halfpipe. Thirty-nine per cent of the injuries were expected to prevent the athlete from participating in competition or training. Women suffered 50% more illnesses than men. The rate of illness was highest in skeleton, short track, curling, cross-country skiing, figure skating, bobsleigh and aerial skiing. A total of 159 illnesses (64%) affected the respiratory system, and the most common cause of illness was infection (n=145, 58%). Overall, 12% of the athletes incurred at least one injury during the games, and 8% an illness, which is similar to prior Olympic Games. The incidence of injuries and illnesses varied substantially between sports. 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.
Birckelbaw, Lourdes G.
A ski jump model was developed to predict ski jump takeoff performance for a short takeoff and vertical landing (STOVL) aircraft. The objective was to verify the model with results from a piloted simulation of a mixed flow, remote lift STOVL aircraft. The prediction model is discussed. The predicted results are compared with the piloted simulation results. The ski jump model can be utilized for basic research of other thrust vectoring STOVL aircraft performing a ski jump takeoff.
The arthrography is one of the most important diagnostic methods of sport injuries of the knee joint. The examination must give an exact information to the surgeon; a good technique and standard X-rays are an absolute postulate. The submitted examinations are based on 6687 arthrographies during a period of 5 years. The arthrography should not be carried out before the acute symptomatology has ceased, usually after an interval of 2-3 weeks. Most frequent are the meniscus injuries by rotary traumas of the knee-joint. Football as the most popular sport is responsible for more than 50% of the injuries, followed by skiing, handball and jogging.
The arthrography is one of the most important diagnostic methods of sport injuries of the knee joint. The examination must give an exact information to the surgeon; a good technique and standard X-rays are an absolute postulate. The submitted examinations are based on 6687 arthrographies during a period of 5 years. The arthrography should not be carried out before the acute symptomatology has ceased, usually after an interval of 2-3 weeks. Most frequently are the meniscus injuries by rotary traumas of the knee-joint. Football as the most popular sport is responsible for more than 50% of the injuries, followed by skiing, handball and jogging. (orig.)
Made, C; Borg, H; Thelander, D; Elmqvist, L G
This study evaluated telemark injuries in a Swedish ski area in terms of injury ratio, location, and causes over time. During the seasons of 1989-2000 all injured telemark skiers ( n=94) who attended the medical center in Tärnaby, Sweden, within 48 h after the accident were registered and asked to fill in an injury form. A control group of noninjured telemark skiers were interviewed in the season of 1999-2000. The most common cause of injury was fall (70%) and the injury ratio was 1.2. There was a higher proportion of beginners in the injured population, and they had a fall/run ratio of 0.7, compared with 0.3 for average and advanced skiers. Ankle/foot injuries were most common (28% of injuries) followed by knee (20%) and head/neck (17%). The ankle/foot injuries decreased from 35% to 22% in the seasons 1989-1995 to 1995-2000. Beginners had more ankle/foot injuries than skilled participants. The severity of ankle/foot injuries classified as the Abbreviated Injury Scale group 2 or higher decreased from 33% to 21% during the study period. Twenty-seven percent used plastic and 73% leather boots. We found no association between boot material and ankle/foot injuries. The proportion of high boots with two or more buckles was 51%. High boots appeared to be protective against ankle/foot injuries. The proportion of high boots increased from 24% to 67% during the study period. Thus ankle/foot injuries were the most common injury location, but have decreased over time. The severity of these injuries has also decreased. A possible explanation could be the increased use of high boots.
Full Text Available Ski protein is implicated in proliferation/differentiation in a variety of cells. We had previously reported that Ski protein is present in granulosa cells of atretic follicles, but not in preovulatory follicles, suggesting that Ski has a role in apoptosis of granulosa cells. The alternative fate of granulosa cells other than apoptosis is to differentiate to luteal cells; however, it is unknown whether Ski is expressed and has a role in granulosa cells undergoing luteinization. Thus, the aim of the present study was to locate Ski protein in the rat ovary during luteinizationto predict the possible role of Ski. In order to examine the expression pattern of Ski protein along with the progress of luteinization, follicular growth was induced by administration of equine chorionic gonadtropin to immature female rats, and luteinization was induced by human chorionic gonadtropin treatment to mimic luteinizing hormone (LH surge. While no Ski-positive granulosa cells were present in preovulatory follicle, Ski protein expression was induced in response to LH surge, and was maintained after the formation of the corpus luteum (CL. Though Ski protein is absent in granulosa cells of preovulatory follicle, its mRNA (c-Ski was expressed and the level was unchanged even after LH surge. Taken together, these results demonstrated that Ski protein expression is induced in granulosa cells upon luteinization, and suggests that its expression is regulated post-transcriptionally.
da Rocha, Alisson L; Pereira, Bruno C; Pauli, José R; de Souza, Claudio T; Teixeira, Giovana R; Lira, Fábio S; Cintra, Dennys E; Ropelle, Eduardo R; Júnior, Carlos R B; da Silva, Adelino S R
The aim of this study was to verify the effects of running overtraining protocols performed in downhill, uphill, and without inclination on the proteins related to hypertrophy signaling pathway in extensor digitorum longus (EDL) and soleus of C57BL/6 mice. We also performed histological and stereological analyses. Rodents were divided into control (CT; sedentary mice), overtrained by downhill running (OTR/down), overtrained by uphill running (OTR/up), and overtrained by running without inclination (OTR). The incremental load, exhaustive, and grip force tests were used as performance evaluation parameters. 36 h after the grip force test, EDL and soleus were removed and immediately used for immunoblotting analysis or stored at -80°C for histological and stereological analyses. For EDL, OTR/down decreased the protein kinase B (Akt) and tuberous sclerosis protein 2 (TSC2) phosphorylation (p), and increased myostatin, receptor-activated Smads (pSMAD2-3), and insulin receptor substrate-1 (pIRS-1; Ser307/636). OTR/down also presented low and high relative proportions of cytoplasm and connective tissue, respectively. OTR/up increased the mammalian target of rapamycin (pmTOR), 70-kDa ribosomal protein S6 kinase 1 (pS6K1) and pSMAD2-3, and decreased pTSC2. OTR decreased pTSC2 and increased pIRS-1 (Ser636). For soleus, OTR/down increased S6 ribosomal protein (pS6RP) and pSMAD2-3, and decreased pIRS-1 (Ser639). OTR/up decreased pS6K1, pS6RP and pIRS-1 (Ser639), and increased pTSC2 (Ser939), and pSMAD2-3. OTR increased pS6RP, 4E-binding protein-1 (p4E-BP1), pTSC2 (Ser939), and pSMAD2-3, and decreased pIRS-1 (Ser639). In summary, OTR/down inhibited the skeletal muscle hypertrophy with concomitant signs of atrophy in EDL. The effects of OTR/up and OTR depended on the analyzed skeletal muscle type. © 2015 Wiley Periodicals, Inc.
Section 11 of the Act (1984:3) on Nuclear Activities stipulates that the holder of a licence to own or operate a nuclear power reactor shall ensure that the necessary comprehensive research and development work is conducted in order to safely handle and finally dispose of the nuclear waste produced and to safely decommission and dismantle installation where the nuclear activity is no longer carried out. According to section 12 of the Act on nuclear activities, the reactor owners shall, in consultation with each other, prepare or have prepared a programme for the necessary comprehensive research and development work and the other measures. The programme shall contain an overview of all measures that may be necessary and also specify, in detail, the measures that are intended to be taken within a period of at least six years. The programme shall be submitted to the Government or to the authority designated by the Government for examination and evaluation. According to section 22 of the ordinance on nuclear activities, the Swedish Nuclear Power Inspectorate (SKI) shall ensure that the research and development work which the reactor owners are responsible for undertaking according to sections 11 and 12 of the act of nuclear activities, is actually carried out. SKIs premise for evaluating the programme has been to examine it as an integrated R and D programme, which essentially focusses on structure, strategy and planning in order to effectively realize the defined goals of the programme, i.e. finding a safe, final solution to the disposal of spent nuclear fuel. Keeping to the time-schedule should not be the controlling factor in carrying out the research and development programme. The essential objective is to attain the goal without jeopardizing quality. SKIs examination has been documented in the form of the following: summary and conclusions, evaluation report, report of comments by reviewing bodies, and consultants reports. SKIs statement to the Government has been
Lindemann, Ulrich; Schwenk, Michael; Schmitt, Syn; Weyrich, Michael; Schlicht, Wolfgang; Becker, Clemens
Wheeled walkers are recommended to improve walking performance in older persons and to encourage and assist participation in daily life. Nevertheless, using a wheeled walker can cause serious problems in the natural environment. This study aimed to compare uphill and downhill walking with walking level in geriatric patients using a wheeled walker. Furthermore, we investigated the effect of using a wheeled walker with respect to dual tasking when walking level. A total of 20 geriatric patients (median age 84.5 years) walked 10 m at their habitual pace along a level surface, uphill and downhill, with and without a standard wheeled walker. Gait speed, stride length and cadence were assessed by wearable sensors and the walk ratio was calculated. When using a wheeled walker while walking level the walk ratio improved (0.58 m/[steps/min] versus 0.57 m/[steps/min], p = 0.023) but gait speed decreased (1.07 m/s versus 1.12 m/s, p = 0.020) when compared to not using a wheeled walker. With respect to the walk ratio, uphill and downhill walking with a wheeled walker decreased walking performance when compared to level walking (0.54 m/[steps/min] versus 0.58 m/[steps/min], p = 0.023 and 0.55 m/[steps/min] versus 0.58 m/[steps/min], p = 0.001, respectively). At the same time, gait speed decreased (0.079 m/s versus 1.07 m/s, p walker improved the quality of level walking but the performance of uphill and downhill walking was worse compared to walking level when using a wheeled walker.
Full Text Available Prof. Kazimierz Bartoszyński was one of the most respected theoreticians of literature in Poland. He worked closely with the Institute of Literary Research of the Polish Academy of Sciences. The period of Professor Bartoszyński’s greatest activity as a researcher coincided with the time when he was fascinated with structuralism, but his interests went far beyond these methodological issues. The author of this memoir, who was the Professor’s doctoral student, portrays him through the prism of their conversations on scholarly topics and her private relationship with Mr. and Mrs. Bartoszyński, which lasted for many years.
Koesters, A.; Poetzelsberger, B.; Dela, F.
The aim of this study was to monitor the long-term effects of skiing on health-related parameters and implant related factors like loosening and wear in patients with total knee arthroplasty. This paper describes the overall study design, general demographics, and physiological demand of the inte......The aim of this study was to monitor the long-term effects of skiing on health-related parameters and implant related factors like loosening and wear in patients with total knee arthroplasty. This paper describes the overall study design, general demographics, and physiological demand...
Schaff, P; Hauser, W
In contrast to the drop in the incidence of fractures of the lower leg that has been observed in recent years, the incidence of knee injuries has not decreased in skiing. There has even been a relative increase of severe knee lesions and isolated ACL ruptures, prompting us to conduct a comprehensive study of the causes of this phenomena. The goal of the study was to develop a new measuring device for alpine skiing research by combining motion analysis, pressure and force measurement, comprehensive examine the forward/backward movement in skiboots in the lab and by means of telemetry on the slope (Skiboot versus knee joint part 1/Sportverlerletzung. Sportschaden 3, 1989, pp. 149-161) and to come up with a proposal for a new safety concept to reduce the high number of knee injuries in alpine skiing in the future. The first study was devoted to the forward movement in skiboots (Skiboot versus knee joint part 2/Sportverletzung. Sportschaden 4, 1990, pp. 1-13). The results showed that a skiing style in backward lean position was adopted by skiers wearing boots with a stiff forward flexion and was supported by the fixed backward spoiler. In order to quantify the influence of the backward spoiler a special skiboot was constructed allowing the rear spoiler to give way at a variable, defined stiffness and register the angular displacement and horizontal force Fh. The results showed most clearly that even a medium rear spoiler resistance will sign, reduce the peak force values by a factor of 5.5. The acceleration at the knee joint level is significantly higher (factor 1.6, p less than 0.05) in case of a rigid spoiler. The lab tests could be confirmed on the slope (sign. reduction of max. force by factor 8). It also proved that normal skiing can be performed in such a boot without limitations. In consideration of our facts it is concluded that the principle of safety bindings must definitely apply in future in equal measure also to the ski boot. As a proposal for future
Kowalski, Erik; Li, Jing Xian
This study investigated the normal and parallel ground reaction forces during downhill and uphill running in habitual forefoot strike and habitual rearfoot strike (RFS) runners. Fifteen habitual forefoot strike and 15 habitual RFS recreational male runners ran at 3 m/s ± 5% during level, uphill and downhill overground running on a ramp mounted at 6° and 9°. Results showed that forefoot strike runners had no visible impact peak in all running conditions, while the impact peaks only decreased during the uphill conditions in RFS runners. Active peaks decreased during the downhill conditions in forefoot strike runners while active loading rates increased during downhill conditions in RFS runners. Compared to the level condition, parallel braking peaks were larger during downhill conditions and parallel propulsive peaks were larger during uphill conditions. Combined with previous biomechanics studies, our findings suggest that forefoot strike running may be an effective strategy to reduce impacts, especially during downhill running. These findings may have further implications towards injury management and prevention.
Macdermid, Paul W; Fink, Philip W; Miller, Matthew C; Stannard, Stephen
Non-propulsive work demand has been linked to reduced energetic economy of cross-country mountain biking. The purpose of this study was to determine mechanical, physiological and performance differences and observe economy while riding a downhill section of a cross-country course prior to and following the metabolic "load" of a climb at race pace under two conditions (hardtail and full suspension) expected to alter vibration damping mechanics. Participants completed 1 lap of the track incorporating the same downhill section twice, under two conditions (hardtail and full suspension). Performance was determined by time to complete overall lap and specific terrain sections. Power, cadence, heart rate and oxygen consumption were sampled and logged every second while triaxial accelerometers recorded accelerations (128 Hz) to quantify vibration. No differences between performance times (P = 0.65) or power outputs (P = 0.61) were observed while physiological demand of loaded downhill riding was significantly greater (P 0.05) measures. This study showed minimal advantage of a full suspension bike in our trial, with further investigations over a full race distance warranted.
Full Text Available Purpose: to substantiate model characteristics of functional fitness components of elite ski-racers, depending on competitions’ conditions. Material: We tested 20 sportsmen of combined team of Ukraine. Results: it was found that climbing hills of different length and steepness is accompanied by certain functional tension of organism and changes in cardio-respiratory system. It influences on effectiveness of further descent and moving on plain. It was also determined that correlation of aerobic and anaerobic efficiency changes according to trail relief. Conclusions: we worked out model characteristics of skiers’ fitness most important parameters, usage of which can facilitate maintaining high special workability on all segments of competition distance. In particular it concerns climbing hills of different steepness.
Ballangan, Cherry; Wang, Xiuying; Eberl, Stefan; Fulham, Michael; Feng, Dagan
We propose an automated lung tumor segmentation method for whole body PET images based on a novel downhill region growing (DRG) technique, which regards homogeneous tumor hotspots as 3D monotonically decreasing functions. The method has three major steps: thoracic slice extraction with K-means clustering of the slice features; hotspot segmentation with DRG; and decision tree analysis based hotspot classification. To overcome the common problem of leakage into adjacent hotspots in automated lung tumor segmentation, DRG employs the tumors' SUV monotonicity features. DRG also uses gradient magnitude of tumors' SUV to improve tumor boundary definition. We used 14 PET volumes from patients with primary NSCLC for validation. The thoracic region extraction step achieved good and consistent results for all patients despite marked differences in size and shape of the lungs and the presence of large tumors. The DRG technique was able to avoid the problem of leakage into adjacent hotspots and produced a volumetric overlap fraction of 0.61 +/- 0.13 which outperformed four other methods where the overlap fraction varied from 0.40 +/- 0.24 to 0.59 +/- 0.14. Of the 18 tumors in 14 NSCLC studies, 15 lesions were classified correctly, 2 were false negative and 15 were false positive.
Engebretsen, Lars; Steffen, Kathrin; Alonso, Juan Manuel; Aubry, Mark; Dvorak, Jiri; Junge, Astrid; Meeuwisse, Willem; Mountjoy, Margo; Renström, Per; Wilkinson, Mike
Identification of high-risk sports, including their most common and severe injuries and illnesses, will facilitate the identification of sports and athletes at risk at an early stage. To analyse the frequencies and characteristics of injuries and illnesses during the XXI Winter Olympic Games in Vancouver 2010. All National Olympic Committees' (NOC) head physicians were asked to report daily the occurrence (or non-occurrence) of newly sustained injuries and illnesses on a standardised reporting form. In addition, the medical centres at the Vancouver and Whistler Olympic clinics reported daily on all athletes treated for injuries and illnesses. Physicians covering 2567 athletes (1045 females, 1522 males) from 82 NOCs participated in the study. The reported 287 injuries and 185 illnesses resulted in an incidence of 111.8 injuries and 72.1 illnesses per 1000 registered athletes. In relation to the number of registered athletes, the risk of sustaining an injury was highest for bobsleigh, ice hockey, short track, alpine freestyle and snowboard cross (15-35% of registered athletes were affected in each sport). The injury risk was lowest for the Nordic skiing events (biathlon, cross country skiing, ski jumping, Nordic combined), luge, curling, speed skating and freestyle moguls (less than 5% of registered athletes). Head/cervical spine and knee were the most common injury locations. Injuries were evenly distributed between training (54.0%) and competition (46.0%; p=0.18), and 22.6% of the injuries resulted in an absence from training or competition. In skeleton, figure and speed skating, curling, snowboard cross and biathlon, every 10th athlete suffered from at least one illness. In 113 illnesses (62.8%), the respiratory system was affected. At least 11% of the athletes incurred an injury during the games, and 7% of the athletes an illness. The incidence of injuries and illnesses varied substantially between sports. Analyses of injury mechanisms in high-risk Olympic winter
Chen, Yi; Pirisi, Lucia; Creek, Kim E.
We compared the levels of the Ski oncoprotein, an inhibitor of transforming growth factor-beta (TGF-β) signaling, in normal human keratinocytes (HKc), HPV16 immortalized HKc (HKc/HPV16), and differentiation resistant HKc/HPV16 (HKc/DR) in the absence and presence of TGF-β. Steady-state Ski protein levels increased in HKc/HPV16 and even further in HKc/DR, compared to HKc. TGF-β treatment of HKc, HKc/HPV16, and HKc/DR dramatically decreased Ski. TGF-β-induced Ski degradation was delayed in HKc/DR. Ski and phospho-Ski protein levels are cell cycle dependent with maximal Ski expression and localization to centrosomes and mitotic spindles during G2/M. ShRNA knock down of Ski in HKc/DR inhibited cell proliferation. More intense nuclear and cytoplasmic Ski staining and altered Ski localization were found in cervical cancer samples compared to adjacent normal tissue in a cervical cancer tissue array. Overall, these studies demonstrate altered Ski protein levels, degradation and localization in HPV16-transformed human keratinocytes and in cervical cancer. - Highlights: • Ski oncoprotein levels increase during progression of HPV16-transformed cells. • Ski and phospho-Ski protein levels are cell cycle dependent. • Ski knock-down in HPV16-transformed keratinocytes inhibited cell proliferation. • Cervical cancer samples overexpress Ski
Full Text Available The aim of the study is to provide a comprehensive, integrated modified technique of personal psycho-physiological regulation based on a system of Raja Yoga. The study involved candidates and masters of sports of freestyle skiing in the amount of 21 people aged 17 to 23 years. Found that athletes co 2 and stage 3 of the hypnotic state successfully acquired by dhyana and can apply it in preparation for a competition. The proposed method includes a high quality optimal fighting condition, modeling and programming training and competitive processes using deferred units, the correction of motor skills. Athletes in their imagination run program of the second day of competition. Then, the third day of competition modeled, programmed overall health. Are told that in the day of the event will have a good mood, great feeling, a surge of strength, vigor, vitality, desire to show all of their sporting qualities.
松本, 裕史; 中西, 匠; Hiroshi, Matsumoto; Takumi, Nakanishi
The purpose of this study was to examine the effects of a ski training program, grounded in the“ buddy system,” on the skiing techniques of students at a women’s university. A group of twelve students, serving as the intervention group, participated in the ski training program using the buddy system, while another group of twelve students participated in program lacking the buddy system, as a control group. The measurement of skiing techniques（ parallel turn, stem turn and wedeln） was conduct...
Lollo, Pablo C B; Moura, Carolina S; Morato, Priscila N; Amaya-Farfan, Jaime
Running on a horizontal plane is known to increase the concentration of the stress biomarker heat-shock protein (HSP), but no comparison of the expression of HSP70 has yet been established between the uphill (predominantly concentric) and downhill (predominantly eccentric) muscle contractions exercise. The objective of the study was to investigate the relationships between eccentric and concentric contractions on the HSP70 response of the lung, kidney, gastrocnemius, soleus and heart. Twenty-four male Wistar weanling rats were divided into four groups: non-exercised and three different grades of treadmill exercise groups: horizontal, uphill (+7%) and downhill (-7% of inclination). At the optimal time-point of six hours after the exercise, serum uric acid, creatine kinase (CK) and lactate dehydrogenase (LDH) were determined by standard methods and HSP70 by the Western blot analysis. HSP70 responds differently to different types of running. For kidney, heart, soleus and gastrocnemius, the HSP70 expression increased, 230, 180, 150 and 120% respectively of the reference (horizontal). When the contraction was concentric (uphill) and compared to downhill the increase in response of HSP70 was greater in 80% for kidney, 75% for gastrocnemius, 60% for soleus and 280% for the heart. Uric acid was about 50% higher (0.64 ± 0.03 mg·dL(-1)) in the uphill group as compared to the horizontal or downhill groups. Similarly, the activities of serum CK and LDH were both 100% greater for both the uphill and downhill groups as compared to the horizontal group (2383 ± 253 and 647.00 ± 73 U/L, respectively). The responsiveness of HSP70 appeared to be quite different depending on the type of tissue, suggesting that the impact of exercise was not restricted to the muscles, but extended to the kidney tissue. The uphill exercise increases HSP70 beyond the eccentric type and the horizontal running was a lower HSP70 responsive stimulus. Key PointsExercise can induce increases in HSP70 in
Parkhouse, Bonnie L., Ed.; And Others
Traditional teaching and coaching positions have become scarce but the expanding field of sport management has created its own job market, demanding new skills and preparation. Three articles are offered that explore different aspects and possibilities for a sport management career. (DF)
Missouri State Dept. of Health, Jefferson City.
This guide deals with various aspects of sports and nutrition. Twelve chapters are included: (1) "Sports and Nutrition"; (2) "Eat to Compete"; (3) "Fit Folks Need Fit Food"; (4) "The Food Guide Pyramid"; (5) "Fat Finder's Guide"; (6) "Pre- and Post-Event Meals"; (7) "Tips for the…
Marieke van Bakel; Ine Pulles; Annet Tiessen-Raaphorst; Frank den Hertog; Robert Vonk; Casper Schoemaker
Deze publicatie verschijnt enkel digitaal op www.sporttoekomstverkenning.nl. Welke maatschappelijke veranderingen beïnvloeden de sport in Nederland? Waar gaat het heen met de sport tussen nu en 2040? Welke kansen, maar ook keuzes biedt dit voor de sportsector en het sportbeleid? Deze vragen
Reiter, M.; Singer, G.; Major, Z.
The quality of the ski boots plays an extraordinary important role in the performance and in the safety of the skiers. The deformation behavior of a racing class ski boot was characterized by using the digital image correlation technique in this study. The boot was gripped in the ski binding and 3 types of motions of the skiers and the deformations of the boot were simulated by a professional skier in the laboratory. First, the buckles were closed in 4 stages and the resulting strains were measured. Furthermore, the skier positioned his balance continuously forward, resulting in a high overall bending deformation of the boot. The leg of the skier acted as a bending arm and pushed the upper part of the boot forward. This loading situation was assumed as quasistatic and was repeated several times. Finally, the skier jumped and this dynamic movement was recorded by using two high speed cameras for 3D analysis. Special focus was devoted to the measurement of the deformation of the boot during the contact of the ski with the ground of the laboratory. Both the displacement of the upper part and the local strain in selected areas of the boot was determined for both quasi-static and dynamic test conditions and are discussed in the paper.
Buckmaster, Melanie E.; Young, Sarah J.
In August 2012, Barbara Fakhouri visited Ober Gatlinburg, a ski resort located in eastern Tennessee to vacation with her family. Ms. Fakhouri used a wheelchair to ambulate. Despite the absence of snow on the ground, the resort operated year-round with many amenities such as an amusement park, restaurant, lounge, and shopping center to captivate…
Lindinger, Stefan Josef; Göpfert, Caroline; Stöggl, Thomas; Müller, Erich; Holmberg, Hans-Christer
Diagonal skiing as a major classical technique has hardly been investigated over the last two decades, although technique and racing velocities have developed substantially. The aims of the present study were to 1) analyse pole and leg kinetics and kinematics during submaximal uphill diagonal roller skiing and 2) identify biomechanical factors related to performance. Twelve elite skiers performed a time to exhaustion (performance) test on a treadmill. Joint kinematics and pole/plantar forces were recorded separately during diagonal roller skiing (9 degrees; 11 km/h). Performance was correlated to cycle length (r = 0.77; P Push-off demonstrated performance correlations for impulse of leg force (r = 0.84), relative duration (r= -0.76) and knee flexion (r = 0.73) and extension ROM (r = 0.74). Relative time to peak pole force was associated with performance (r = 0.73). In summary, diagonal roller skiing performance was linked to 1) longer cycle length, 2) greater impulse of force during a shorter push-off with larger flexion/extension ROMs in leg joints, 3) longer leg swing, and 4) later peak pole force, demonstrating the major key characteristics to be emphasised in training.
Nieboer, T.E.; Assmann, R.F.; Withagen, M.I.J.; Geeraedts, L.M.G.
A 28-year-old female sustained an anorectal rupture after a fall from a jet ski. The rupture was sutured and a double-loop colostomy was created. Three months later, following a test of functional continence, the colostomy was removed. The patient recovered without complications and with
Mygind, Erik; Larsson, Benny; Klausen, Tom
-poling was correlated with performance, expressed as a ranking score during 10 ski races. The tests were undertaken in September, December and April. Upper body maximal oxygen uptake increased 5.8% from September to December, decreasing to 2.3% above the September level in April. Upper body work output (2 min...
... fleet. Also, the location of the current maintenance shop impedes traffic flow and removes potential... new Sunrise Vehicle Maintenance Shop on the north side of the Sunrise parking lot. DATES: Comments... increasing parking capacity and improving traffic flow in at Mt. Hood Meadows Ski Resort. Parking capacity...
The main aim of this paper is to find formulae for the computation of the geodesic metric on the Sierpiński carpet. This is accomplished by introducing carpet coordinates. Subsequently we show the equivalence of the Euclidean and the geodesic metric on this fractal. Mathematics Subject Classification (2000): 28A80, 54E35 ...
Kristensen, M.; Pötzelsberger, B.; Scheiber, P.
We investigated the effect of alpine skiing for 12 weeks on skeletal muscle characteristics and biomarkers of glucose homeostasis and cardiovascular risk factors. Twenty-three patients with a total knee arthroplasty (TKA) were studied 2.9 ± 0.9 years (mean ± SD) after the operation. Fourteen...
To highlight and discuss the considerations for the future development of equipment standards for Winter Paralympic sports. Literature searches were performed (in English) during May 2011 using the key words "technology, winter sport, Olympic, and Paralympic" in the computerized databases PubMed, PsycINFO, Science Direct, and Google Scholar. In addition, personal scientific observations were made at several Winter Paralympic Games. The retrieved articles were screened and assessed for relevance to the biological, biomechanical, and sport medicine aspects of equipment. There are 3 key areas in which technology has influenced sports performance in Paralympic winter sports, namely, specialized prostheses, crutch skis or outriggers (in lieu of poles), and sport-specific wheelchairs (such as the sit-ski). From a sport medicine perspective, a crucial factor not considered in the standard laboratory test of mechanical efficiency is the influence of the human-equipment connection, such as the stump-to-prosthesis interface or the required human-to-wheelchair control. This connectivity is critical to the effective operation of the assistive device. When assessing the efficiency of this equipment, the not-so-obvious, holistic, compensatory factors need to be considered. Assistive equipment is fundamental for a person with a disability to participate and compete in winter sport activities. Although there have been improvements in the mechanical function of some assistive devices, the key issue is matching the residual function of the person with the assistive equipment. Equitable access to this technology will also ensure that the fundamental spirit of fair play that underpins the Paralympic Games is maintained.
Looney, Marilyn A
Many sports, such as, gymnastics, diving, ski jumping, and figure skating, use judges' scores to determine the winner of a competition. These judges use some type of rating scale when judging performances (e.g., figure skating: 0.0 - 6.0). Sport governing bodies have the responsibility of setting and enforcing quality control parameters for judge performance. Given the judging scandals in figure skating at the 1998 and 2002 Olympics, judge performance in sport is receiving greater scrutiny. The purpose of this article is to illustrate how results from Rasch analyses can be used to provide in-depth feedback to judges about their scoring patterns. Nine judges' scores for 20 pairs of figure skaters who competed at the 2002 Winter Olympics were analyzed using a four-faceted (skater pair ability, skating aspect difficulty, program difficulty, and judge severity) Rasch rating scale model that was not common to all judges. Fit statistics, the logical ordering of skating aspects, skating programs, and separation indices all indicated a good fit of the data to the model. The type of feedback that can be given to judges about their scoring pattern was illustrated for one judge (USA) whose performance was flagged as being unpredictable. Feedback included a detailed description of how the rating scale was used; for example, 10% of all marks given by the American judge were unexpected by the model (Z > |2|). Three figures illustrated differences between the judge's observed and expected marks arranged according to the pairs' skating order and final placement in the competition. Scores which may represent "nationalistic bias" or a skating order influence were flagged by looking at these figures. If sport governing bodies wish to improve the performance of their judges, they need to employ methods that monitor the internal consistency of each judge as a many-facet Rasch analysis does.
Pons, Marc; Scott, Daniel; Steiger, Robert; Rutty, Michelle; Johnson, Peter; Vilella, Marc
The multi-billion dollar global ski industry is one of the tourism subsectors most directly impacted by climate variability and change. In the decades ahead, the scholarly literature consistently projects decreased reliability of natural snow cover, shortened and more variable ski seasons, as well as increased reliance on snowmaking with associated increases in operational costs. In order to develop the coupled snow, ski operations and demand model for the Ontario ski region (which represents approximately 18% of Canada's ski market), the research utilized multiple methods, including: a in situ survey of over 2400 skiers, daily operations data from ski resorts over the last 10 years, climate station data (1981-2013), climate change scenario ensemble (AR5 - RCP 8.5), an updated SkiSim model (building on Scott et al. 2003; Steiger 2010), and an agent-based model (building on Pons et al. 2014). Daily snow and ski operations for all ski areas in southern Ontario were modeled with the updated SkiSim model, which utilized current differential snowmaking capacity of individual resorts, as determined from daily ski area operations data. Snowmaking capacities and decision rules were informed by interviews with ski area managers and daily operations data. Model outputs were validated with local climate station and ski operations data. The coupled SkiSim-ABM model was run with historical weather data for seasons representative of an average winter for the 1981-2010 period, as well as an anomalously cold winter (2012-13) and the record warm winter in the region (2011-12). The impact on total skier visits and revenues, and the geographic and temporal distribution of skier visits were compared. The implications of further climate adaptation (i.e., improving the snowmaking capacity of all ski areas to the level of leading resorts in the region) were also explored. This research advances system modelling, especially improving the integration of snow and ski operations models with
Thomas Stöggl, Christoph Schwarzl, Edith E. Müller, Masaru Nagasaki, Julia Stöggl, Peter Scheiber, Martin Schönfelder, Josef Niebauer
Full Text Available Since physical inactivity especially prevails during winter months, we set out to identify outdoor alternatives to indoor cycling (IC by comparing the metabolic and cardiorespiratory responses during alpine skiing (AS, cross-country skiing (XCS and IC and analyse the effects of sex, age and fitness level in this comparison. Twenty one healthy subjects performed alpine skiing (AS, cross-country skiing (XCS, and IC. Oxygen uptake (VO2, total energy expenditure (EE, heart rate (HR, lactate, blood glucose and rate of perceived exertion (RPE were determined during three 4-min stages of low, moderate and high intensity. During XCS and IC VO2max and EE were higher than during AS. At least 2½ hours of AS are necessary to reach the same EE as during one hour of XCS or IC. HR, VO2, lactate, and RPEarms were highest during XCS, whereas RPEwhole-body was similar and RPElegs lower than during AS and IC, respectively. Weight adjusted VO2 and EE were higher in men than in women while fitness level had no effect. Male, fit and young participants were able to increase their EE and VO2 values more pronounced. Both AS and XCS can be individually tailored to serve as alternatives to IC and may thus help to overcome the winter activity deficit. XCS was found to be the most effective activity for generating a high EE and VO2 while AS was the most demanding activity for the legs.
Kimel-Naor, Shani; Gottlieb, Amihai; Plotnik, Meir
It has been shown that gait parameters vary systematically with the slope of the surface when walking uphill (UH) or downhill (DH) (Andriacchi et al., 1977; Crowe et al., 1996; Kawamura et al., 1991; Kirtley et al., 1985; McIntosh et al., 2006; Sun et al., 1996). However, gait trials performed on inclined surfaces have been subject to certain technical limitations including using fixed speed treadmills (TMs) or, alternatively, sampling only a few gait cycles on inclined ramps. Further, prior work has not analyzed upper body kinematics. This study aims to investigate effects of slope on gait parameters using a self-paced TM (SPTM) which facilitates more natural walking, including measuring upper body kinematics and gait coordination parameters. Gait of 11 young healthy participants was sampled during walking in steady state speed. Measurements were made at slopes of +10°, 0° and -10°. Force plates and a motion capture system were used to reconstruct twenty spatiotemporal gait parameters. For validation, previously described parameters were compared with the literature, and novel parameters measuring upper body kinematics and bilateral gait coordination were also analyzed. Results showed that most lower and upper body gait parameters were affected by walking slope angle. Specifically, UH walking had a higher impact on gait kinematics than DH walking. However, gait coordination parameters were not affected by walking slope, suggesting that gait asymmetry, left-right coordination and gait variability are robust characteristics of walking. The findings of the study are discussed in reference to a potential combined effect of slope and gait speed. Follow-up studies are needed to explore the relative effects of each of these factors. Copyright © 2017. Published by Elsevier Ltd.
Full Text Available BACKGROUND: Qualitative evaluation case study deals with the implementation of mental skills training program conducted with the Czech national junior alpine skiing team over a period of an annual training cycle and evaluation of its eﬀects by one of the members of the team. The concept of the study is based on current findings of sport psychology in the field of mental training in alpine skiing and other sports. The theoretical framework of the study is the socio-cognitive psychological paradigm (Bandura, 1986, 1997 and cognitive-behavioral approach. OBJECTIVE: The aim of the work is a qualitative evaluation of a program involving relaxation, concentration and imaginative techniques and goal setting by one of its participants. METHODS: Evaluation is carried out through semi-structured interview with the participant. The interview was analyzed in a scientific software Atlas.ti 6.2. The method of creating clusters were used for analysis. RESULTS: From the participants answers we understand the subjectively perceived benefit of the program based on understanding of the possibility of influencing the mental part of his performance. The racer presents that he learned the practical application of certain techniques of the mental preparation, particularly imagery and the mental plan of the race, which contributed to better coping with the race situation. The racer achieved the improvement in his FIS ranking standings in all the disciplines over the monitored season. Research findings are used in the proposal of practical recommendations for mental preparation in the training of top and performing skiers. CONCLUSION: An important factor in the success of the mental skills training program is cooperation of all interested participants, that are athlete, coach and psychologist. With applying the psychological techniques the key factors are mental support, encouragement, and development of confidence of the athlete in his own abilities. A well
Erdmann, Włodzimierz S; Giovanis, Vassilis; Aschenbrenner, Piotr; Kiriakis, Vaios; Suchanowski, Andrzej
This paper aims at the description and comparison of methods of topographic analysis of racing courses at all disciplines of alpine skiing sports for the purposes of obtaining: terrain geomorphology (snowless and with snow), course geometry, and competitors' runs. The review presents specific methods and instruments according to the order of their historical appearance as follows: (1) azimuth method with the use of a compass, tape and goniometer instruments; (2) optical method with geodetic theodolite, laser and photocells; (3) triangulation method with the aid of a tape and goniometer; (4) image method with the use of video cameras; (5) differential global positioning system and carrier phase global positioning system methods. Described methods were used at homologation procedure, at training sessions, during competitions of local level and during International Ski Federation World Championships or World Cups. Some methods were used together. In order to provide detailed data on course setting and skiers' running it is recommended to analyse course geometry and kinematics data of competitors' running for all important competitions.
Schaff, P; Hauser, W
In contrast to the drop in the incidence of fracture of the lower leg that has been observed in recent years, the incidence of knee injuries has not decreased in skiing. There has even been a relative increase of severe knee lesions and isolated ACL ruptures, prompting us to conduct a comprehensive study of the causes of this phenomena. The goal of part 2 of the study was to comprehensively examine the forward movement in skiboots in the lab and on the slope. Studying nine beginners and eight experts, we found a 20% (sign. 0.05) lower forward-lean capability for the beginner group in the same boot. A randomized study with crossover design conducted on the slope, where we equipped 16 skiers with either soft or stiff boots for the duration of five ski days, revealed the learning behaviour and forward position on the slope depending on the boot. The pupils became definitely less adept at learning if they were required to wear stiff skiboots and showed a sign, lower forward flex angle. A skiiing style in backward lean position was adopted and supported by the fixed backward spoiler. Therefore another study was necessary and will follow (part 3) to examine the effect of a stiff backward spoiler and skiing in a backward lean position. In consideration of the facts known up to now, it is concluded that to improve safety in skiing recommendations must be given as to which boot to choose, according to the skiing level. In addition, the setting of safety bindings must consider the type of skiboot used.
Ole Marius Hoel Rindal
Full Text Available The automatic classification of sub-techniques in classical cross-country skiing provides unique possibilities for analyzing the biomechanical aspects of outdoor skiing. This is currently possible due to the miniaturization and flexibility of wearable inertial measurement units (IMUs that allow researchers to bring the laboratory to the field. In this study, we aimed to optimize the accuracy of the automatic classification of classical cross-country skiing sub-techniques by using two IMUs attached to the skier’s arm and chest together with a machine learning algorithm. The novelty of our approach is the reliable detection of individual cycles using a gyroscope on the skier’s arm, while a neural network machine learning algorithm robustly classifies each cycle to a sub-technique using sensor data from an accelerometer on the chest. In this study, 24 datasets from 10 different participants were separated into the categories training-, validation- and test-data. Overall, we achieved a classification accuracy of 93.9% on the test-data. Furthermore, we illustrate how an accurate classification of sub-techniques can be combined with data from standard sports equipment including position, altitude, speed and heart rate measuring systems. Combining this information has the potential to provide novel insight into physiological and biomechanical aspects valuable to coaches, athletes and researchers.
Fitness has become one of the most popular kinds of the mass sport and has completely replaced the traditional “physical culture”. Dozens of variations of fitness and millions of participants pose a great challenge to contemporary architecture. The articles of our issue show the present and the future of architecture for fitness. We present a topical collection with a wide geographical range, including the Irkutsk Agglomeration, Tomsk, Krasnodar, sports in the Moscow Palace of Young Pioneers, and the anthology of the top foreign sports venues.
James A. Tuttle
Full Text Available The leukocyte heat shock response (HSR is used to determine individual's thermotolerance. The HSR and thermotolerance are enhanced following interventions such as preconditioning and/or acclimation/acclimatization. However, it is unclear whether the leukocyte HSR is an appropriate surrogate for the HSR in other tissues implicated within the pathophysiology of exertional heat illnesses (e.g., skeletal muscle, and whether an acute preconditioning strategy (e.g., downhill running can improve subsequent thermotolerance. Physically active, non-heat acclimated participants were split into two groups to investigate the benefits of hot downhill running as preconditioning strategy. A hot preconditioning group (HPC; n = 6 completed two trials (HPC1HOTDOWN and HPC2HOTDOWN of 30 min running at lactate threshold (LT on −10% gradient in 30°C and 50% relative humidity (RH separated by 7 d. A temperate preconditioning group (TPC; n = 5 completed 30 min running at LT on a −1% gradient in 20°C and 50% (TPC1TEMPFLAT and 7 d later completed 30 min running at LT on −10% gradient in 30°C and 50% RH (TPC2HOTDOWN. Venous blood samples and muscle biopsies (vastus lateralis; VL were obtained before, immediately after, 3, 24, and 48 h after each trial. Leukocyte and VL Hsp72, Hsp90α, and Grp78 mRNA relative expression was determined via RT-QPCR. Attenuated leukocyte and VL Hsp72 (2.8 to 1.8 fold and 5.9 to 2.4 fold; p < 0.05 and Hsp90α mRNA (2.9 to 2.4 fold and 5.2 to 2.4 fold; p < 0.05 responses accompanied reductions (p < 0.05 in physiological strain [exercising rectal temperature (−0.3°C and perceived muscle soreness (~ −14%] during HPC2HOTDOWN compared to HPC1HOTDOWN (i.e., a preconditioning effect. Both VL and leukocyte Hsp72 and Hsp90α mRNA increased (p < 0.05 simultaneously following downhill runs and demonstrated a strong relationship (p < 0.01 of similar magnitudes with one another. Hot downhill running is an effective preconditioning strategy
Patricios, Jon S; Ardern, Clare L; Hislop, Michael David; Aubry, Mark; Bloomfield, Paul; Broderick, Carolyn; Clifton, Patrick; Echemendia, Ruben J; Ellenbogen, Richard G; Falvey, Éanna Cian; Fuller, Gordon Ward; Grand, Julie; Hack, Dallas; Harcourt, Peter Rex; Hughes, David; McGuirk, Nathan; Meeuwisse, Willem; Miller, Jeffrey; Parsons, John T; Richiger, Simona; Sills, Allen; Moran, Kevin B; Shute, Jenny; Raftery, Martin
The 2017 Berlin Concussion in Sport Group Consensus Statement provides a global summary of best practice in concussion prevention, diagnosis and management, underpinned by systematic reviews and expert consensus. Due to their different settings and rules, individual sports need to adapt concussion guidelines according to their specific regulatory environment. At the same time, consistent application of the Berlin Consensus Statement's themes across sporting codes is likely to facilitate superior and uniform diagnosis and management, improve concussion education and highlight collaborative research opportunities. This document summarises the approaches discussed by medical representatives from the governing bodies of 10 different contact and collision sports in Dublin, Ireland in July 2017. Those sports are: American football, Australian football, basketball, cricket, equestrian sports, football/soccer, ice hockey, rugby league, rugby union and skiing. This document had been endorsed by 11 sport governing bodies/national federations at the time of being published. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Freberg, Baard Ingegerdsson; Olsen, Raymond; Thorud, Syvert; Ellingsen, Dag G; Daae, Hanne Line; Hersson, Merete; Molander, Paal
Preparation of skis prior to skiing competitions involves several individual work operations and the use of a wide variety of chemically based ski waxing products to improve the performance of the skis, including products used after skiing for wax removal and ski sole cleaning. Modern ski waxes consist mainly of petroleum-derived straight-chain aliphatic hydrocarbons, perfluoro-n-alkanes or polyfluorinated n-alkanes. The wax cleaning products contain solvents such as neat aliphatic hydrocarbons (aliphates) or a mixture with limonene. Different ski waxing work operations can result in contaminated workroom atmospheres. The aim of this study was to assess the chemical exposures related to the individual ski waxing work operations by investigating the specific work operations in controlled model experiments. Four main work operations with potential exposures were identified: (i) application of glider waxes, (ii) scraping and brushing of applied glider waxes, (iii) application of base/grip waxes, and (iv) ski sole cleaning. Aerosol particle masses were sampled using conical samplers equipped with 37-mm PVC, 5-µm pore size filters and cyclones equipped with 37-mm PVC, 0.8-µm pore size filters for the inhalable and the respirable aerosol mass fractions, respectively. For measurements of particle number concentrations, a Scanning Mobility Particle Sizer was used. Mean aerosol particle mass concentrations of 18.6 mg m(-3) and 32.2 mg m(-3) were measured during application of glider wax powders in the respirable and in the inhalable aerosol mass fractions, respectively. Particle number concentration of ~900 000 particles cm(-3) was measured during application of glider wax powder products. Ski sole cleaning with products containing aliphates displayed solvent air concentrations up to 62.5 p.p.m. This study shows that the potential exposure to generated particles during ski waxing and ski preparation is considerable, especially during work using glide wax powders.
Harris, Andrew W; Jones, C Allyson; Rowe, Brian H; Voaklander, Donald C
To report the rates of SR-related HIs presenting to EDs in a Canadian population-based sample. Descriptive epidemiology study. Using administrative data, sport and recreation-related emergency department presentations for persons 0-35 years of age, from April 1997 through March 2008, were obtained from the Edmonton Zone (formerly the Capital Health Region), Alberta Health Services through the Ambulatory Care Classification System. Of the 3,230,890 visits to the emergency departments of the five hospitals in Edmonton, 63,219 sport and recreation-related injury records and 4935 sport and recreation-head injury records were identified. Head injuries were most frequently treated for the activities of hockey (20.7%), cycling (12.0%), and skiing/snowboarding/sledding. Males accounted for 71.9% (n=3546) and patients less than 18 years of age sustained 3446 (69.8%) sport and recreation-head injuries. Sport and recreation-related head injuries most frequently treated in emergency departments involve common activities such as hockey, cycling, skiing/snowboarding/sledding, and soccer. Males and those less than 18 years of age sustain the majority of sport and recreation-related head injuries treated in emergency departments. These findings underscore the importance of sport-specific policies and safety promotion for the prevention of head injuries, in sports and recreational activities. Copyright © 2011 Sports Medicine Australia. All rights reserved.
Patel, Darshan P; Redshaw, Jeffrey D; Breyer, Benjamin N; Smith, Thomas G; Erickson, Bradley A; Majercik, Sarah D; Gaither, Thomas W; Craig, James R; Gardner, Scott; Presson, Angela P; Zhang, Chong; Hotaling, James M; Brant, William O; Myers, Jeremy B
Most high-grade renal injuries (American Association for Surgery of Trauma (AAST) grades III-V) result from motor vehicle collisions associated with numerous concomitant injuries. Sports-related blunt renal injury tends to have a different mechanism, a solitary blow to the flank. We hypothesized that high-grade renal injury is often isolated in sports-related renal trauma. We identified patients with AAST grades III-V blunt renal injuries from four level 1 trauma centres across the United States between 1/2005 and 1/2014. Patients were divided into "Sport" or "Non-sport" related groups. Outcomes included rates of hypotension (systolic blood pressure 110bpm), concomitant abdominal injury, and procedural/surgical intervention between sports and non-sports related injury. 320 patients met study criteria. 18% (59) were sports-related injuries with the most common mechanisms being skiing, snowboarding and contact sports (25%, 25%, and 24%, respectively). Median age was 24 years for sports and 30 years for non-sports related renal injuries (p=0.049). Males were more commonly involved in sports related injuries (85% vs. 72%, p=0.011). Median injury severity score was lower for sports related injuries (10 vs. 27, pinjury scale scores. Sports related trauma was more likely to be isolated without other significant injury (69% vs. 39% (psports and non-sports renal injuries (p=0.30). Sports injuries had lower transfusion (7% vs. 47%, psports vs. 18% non-sports, p=0.95). High-grade sports-related blunt renal trauma is more likely to occur in isolation without other abdominal or thoracic injuries and clinicians must have a high suspicion of renal injury with significant blows to the flank during sports activities. Copyright © 2015 Elsevier Ltd. All rights reserved.
Koen Breedveld; Carlijn Kamphuis; Annet Tiessen-Raaphorst
Sport boeit. Sport bindt. Sport bevordert de gezondheid. En sport betaalt. Sport is anno 2008 ongekend populair. Tweederde van de Nederlanders doet aan sport. Na zwemmen en fietsen is fitness de meest populaire sport geworden. Daarnaast zetten anderhalf miljoen Nederlanders zich als vrijwilliger
Breiling, M.; Sokratov, S.
Austria has the highest national added value from winter tourism in Europe, as well as worldwide. 15.7 million arrivals were counted in Austrian accommodation establishments in the 2010/11 winter season. There were more than 62 million overnight stays and 51.2 million skier-days were consumed. 588 million transports were carried out by more than 3000 lifts (cable cars, chair lifts and T-bars). Including indirect and induced effects, this resulted in more than 10 billion euros in added value being generated. The lack of snow in many Austrian skiing areas during the 2006/2007 winter season demonstrated the extent to which meteorological conditions influence operations. Declines in the number of skiers transported and total skier days were the result. The cable-car operators also had to struggle with little snow in the 2010/2011 winter. The Austrian Cable Car Operators' Association stated that the opening of 70-80% of all skiing areas outside of the peak season could only be assured through the use of snowmaking equipment. The central criterion for winter sports enthusiasts to make a trip is the guarantee that they will find snow at their destination and Austria's cable-car operators invest more than 100 million euros in the erection and improvement of snowmaking complexes every year to satisfy this deand. In the 2010/2011 season, this provided for 17,800 jobs. Cable car operators set up snowmaking equipment to become independent from meteorological conditions and improve the capacity utilisation of their expensive investments in transport systems in the early winter. Austria has a skiing area of around 25,400 hectares - around 17,000 hectares at altitudes between 600m and 3200m are currently suitable for snowmaking. As much as 70% of the snow is produced immediately before the start of the season. This recent trend is responsible that the irrigation pattern of Austrian land use changed significantly in the last decade. Previously maize fields and low lands in summer
Recreational or regular physical and sport activities may be responsible for a wide range of cutaneous complications. Among them, "sports purpura" is a peculiar symptom that can occur during a large number of sports. "Effort purpura" defines any purpura occurring within the context of physical exercise irrespective of its cause. Therefore this clinical diagnosis includes various aetiologies. Diagnosis of traumatic purpura is often easy if the sport is mentioned in the anamnesis; cutaneous exercise - induced vasculitis must be also noted. Purpura can reveal systemic diseases or internal haemorrhage, such as spleen rupture, thrombopathies or systemic vasculitis, and other effort purpuras must be taken into account, including those related to the environment (cold, sun exposure...). Knowledge of a physical activity before the occurrence of purpura should be known by practitioner to avoid unnecessary and costly explorations in most of the cases. Copyright © 2012 Elsevier Masson SAS. All rights reserved.
Full Text Available Technology is transforming the games themselves and at times with dire consequences. Tony Kirkbride, Head: CSIR Technology Centre said there are a variety of sports technologies and there have been advances in material sciences and advances...
Full Text Available Due to higher energy consumption, physically active people have higher nutritional requirements. In addition to other important factors for sports, such as good health and physical predisposition, adequate nutrition is a fundamental component. Sports nutrition must be well planned and individually adapted based on physical characteristics, tendencies towards gaining or losing weight, frequency, duration and intensity of training sessions. Studies have shown that a well-balanced ratio of macro and micronutrients, with the support of supplements and adequate hydration, can significantly improve athletic performance and plays a key role in achieving better results. An optimally designed nutritional program, with realistic and achievable goals, which complements a well-planned training program, is the basis for success in sports. Only when nutritional requirements are met, deficits can be prevented and performance in sport pushed to the limit.
Lee, Sangkook; Saetia, Kriangsak; Saha, Suparna; Kline, David G; Kim, Daniel H
The aim of this retrospective study was to present and investigate axillary nerve injuries associated with sports. This study retrospectively reviewed 26 axillary nerve injuries associated with sports between the years 1985 and 2010. Preoperative status of the axillary nerve was evaluated by using the Louisiana State University Health Science Center (LSUHSC) grading system published by the senior authors. Intraoperative nerve action potential recordings were performed to check nerve conduction and assess the possibility of resection. Neurolysis, suture, and nerve grafts were used for the surgical repair of the injured nerves. In 9 patients with partial loss of function and 3 with complete loss, neurolysis based on nerve action potential recordings was the primary treatment. Two patients with complete loss of function were treated with resection and suturing and 12 with resection and nerve grafting. The minimum follow-up period was 16 months (mean 20 months). The injuries were associated with the following sports: skiing (12 cases), football (5), rugby (2), baseball (2), ice hockey (2), soccer (1), weightlifting (1), and wrestling (1). Functional recovery was excellent. Neurolysis was performed in 9 cases, resulting in an average functional recovery of LSUHSC Grade 4.2. Recovery with graft repairs averaged LSUHSC Grade 3 or better in 11 of 12 cases Surgical repair can restore useful deltoid function in patients with sports-associated axillary nerve injuries, even in cases of severe stretch-contusion injury.
Federolf, P; Reid, R; Gilgien, M; Haugen, P; Smith, G
Analyzing an athlete's "technique," sport scientists often focus on preselected variables that quantify important aspects of movement. In contrast, coaches and practitioners typically describe movements in terms of basic postures and movement components using subjective and qualitative features. A challenge for sport scientists is finding an appropriate quantitative methodology that incorporates the holistic perspective of human observers. Using alpine ski racing as an example, this study explores principal component analysis (PCA) as a mathematical method to decompose a complex movement pattern into its main movement components. Ski racing movements were recorded by determining the three-dimensional coordinates of 26 points on each skier which were subsequently interpreted as a 78-dimensional posture vector at each time point. PCA was then used to determine the mean posture and principal movements (PMk ) carried out by the athletes. The first four PMk contained 95.5 ± 0.5% of the variance in the posture vectors which quantified changes in body inclination, vertical or fore-aft movement of the trunk, and distance between skis. In summary, calculating PMk offered a data-driven, quantitative, and objective method of analyzing human movement that is similar to how human observers such as coaches or ski instructors would describe the movement. © 2012 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Dotti, F.; Colonna, M.; Ferri, A.
In this work, the special design of a pair of ski gloves has been assessed in terms of thermal comfort. The glove 2in1 Gore-Tex has a dual-chamber construction, with two possible wearing configurations: one called “grip” to maximize finger flexibility and one called “warm” to maximize thermal insulation in extremely cold conditions. The dual-chamber gloves has been compared with two regular ski gloves produced by the same company. An intermittent test on a treadmill was carried out in a climatic chamber: it was made of four intense activity phases, during which the volunteer ran at 9 km/h on a 5% slope for 4 minutes, spaced out by 5-min resting phases. Finger temperature measurements were compared with the thermal sensations expressed by two volunteers during the test.
The function of SITE-94 is to provide the Swedish Nuclear Power Inspectorate (SKI) with the capacity and supporting knowledge needed for reviewing the Swedish nuclear industry's R and D programs and for reviewing license applications, as stipulated in Swedish legislation. The report is structured as a Performance Assessment exercise needed for input to decisions regarding repository safety, but the SITE-94 is neither a safety assessment nor a model for future assessments to be undertaken by the prospective licensee. The specific project objectives of SITE-94 comprise site evaluation, performance assessment methodology, canister integrity and radionuclide release and transport calculations. The main report (SKI-R--96-36) gives a detailed description of the many inter-related studies undertaken as part of the research project, while the present report presents a condensed summary of the main report. 46 refs
1. A ski-boot should have an adequate arch support and a variable, as well as an exact fitting of the dorsal part. This can be achieved with flow, foam, air or wax. 2. Isolated pressure of compression systems of different kinds should be avoided (e.g. pressure of buckles above the ankle). New results are demonstrated by the possibility of putting on the boot from behind and having the buckles at the back of the boot. 3. The strap from ankle to foot has to be continuous to avoid pressure points. 4. It should be possible to walk and stand in a ski-boot without either muscular strain or pressure on the knee-joint. In addition, the sole has to give an optimal grip also on icy ground to prevent slipping.
The probabilistic system assessment calculation reported in the SKI Project-90 final documents were restricted to the following nuclides: 14 C, 129 I, 135 Cs, 237 Np and 240 Pu. In this report we have extended those calculations to another five nuclides: 79 Se, 243 Am, 240 Pu, 93 Zr and 99 Tc. The execution of probabilistic assessment calculations integrated in the context of SKIs first safety analysis exercise of an hypothetic final repository for high-level nuclear waste in Sweden, was a learning experience of relevance for the conduction of probabilistic safety assessment in future exercises. Some major conclusions and viewpoints of future need related with probabilistic assessment were withdrawn from this work and are presented in our report
Full Text Available Landing and its preparation are important phases for performance and safety of ski jumpers. A correct ski positioning could influence the jump length as also the cushioning effect of the aerodynamic forces that permits the reduction of landing impacts. Consequently, the detection of ski angles during landing preparation could allow for analyzing landing techniques that result in reduced impact forces for the athletes. In this study, two athletes performed with force insoles and inertial sensors positioned on the ski during training conditions on the ski jumping hill. The results confirmed previous studies, showing that impact forces can reach more than four times body weight. In the analyzed cases, the force distribution resulted to be more concentrated on the forefoot and the main movement influencing the impact was the pitch. The combination of inertial sensors, in particular gyroscopes, plus force insoles demonstrated to be an interesting set up for ski jumping movement analysis.
Full Text Available Purpose: analysis of technique of skiing skating style of leading sportsmen of the world. Material and Methods: research was conducted by means of analysis of video data and кинограмм of of skilled racing cross-country ski and biathlon of leading countries of the world. Results: the analysis of dynamic descriptions of technique of the same name ski motions educed the row of factors, from that sportsmen, what applied «Double Push» in the technique of skiing, increase speed of passing of short segments on 4-6%. Conclusions: implementation of «Double Push» can useful for racing cross-country ski and biathlon on competitions on a sprint, on rollers-ski and at implementation of short accelerations on distance, and also on a finish
Haefner, H K; Andersen, H F; Johnson, M P
A 17-year-old woman riding as a passenger on a jet-ski fell behind the jet nozzle while jumping waves. A vaginal laceration with intra-abdominal extension occurred as a result of the accident. Hypogastric artery ligation controlled the hemorrhage and avoided more extensive surgery. The case represents an unusual injury from this type of watercraft and illustrates important points in the management of genital tract trauma.
William C. Wheaton
This paper examines the behavior of ski resort property in a major New England market over the last 25 years. A constructed property price series reveals that nominal prices are quite volatile and only slightly higher today than in 1980. These ?uctuations and trends are investigated with a time series VAR model. The ?ndings indicate that (1) natural snowfall is crucial to business;(2) regional annual business is central to individual resort demand and hence price appreciation; and (3) resort ...
Gardan, N; Schneider, A; Polidori, G; Trenchard, H; Seigneur, J M; Beaumont, F; Fourchet, F; Taiar, R
The purpose of this study is to develop a numerical methodology based on real data from wind tunnel experiments to investigate the effect of the ski jumper's posture and speed on aerodynamic forces in a wide range of angles of attack. To improve our knowledge of the aerodynamic behavior of the ski jumper and his equipment during the early flight phase of the ski jump, we applied CFD methodology to evaluate the influence of angle of attack (α=14°, 21.5°, 29°, 36.5° and 44°) and speed (u=23, 26 and 29m/s) on aerodynamic forces in the situation of stable attitude of the ski jumper's body and skis. The standard k-ω turbulence model was used to investigate both the influence of the ski jumper's posture and speed on aerodynamic performance during the early flight phase. Numerical results show that the ski jumper's speed has very little impact on the lift and drag coefficients. Conversely, the lift and drag forces acting on the ski jumper's body during the early flight phase of the jump are strongly influenced by the variations of the angle of attack. The present results suggest that the greater the ski jumper's angle of inclination, with respect to the relative flow, the greater the pressure difference between the lower and upper parts of the skier. Further studies will focus on the dependency of the parameters with both the angle of attack α and the body-ski angle β as control variables. It will be possible to test and optimize different ski jumping styles in different ski jumping hills and investigate different environmental conditions such as temperature, altitude or crosswinds. Copyright © 2017 Elsevier Ltd. All rights reserved.
Full Text Available Revegetation of ski slopes is a useful technique to limit soil erosion, reduce the visual impact of the tracks and lengthen the duration of snow cover. Restoration is often performed with commercial forage mixtures with the aim of creating a fast soil cover, then allowing the natural recolonization of artificial swards in the mid-long term. To investigate on the recolonization dynamics, data were collected from 21 different plots from the Alps and the Apennines (Valtellina, Plan de Corones, Sappada, Cimone. Knowledge of both the original mixtures used for restoration and the timespan since intervention (ranging from 1 to 21 years allowed to throw light on the naturalization process for the studied plots. Ground cover, floristic richness and relative presence of sown and native species were measured along linear transects established on the analyzed ski tracks. Results showed the effectiveness of plant restoration, in terms of soil coverage and (in some cases persistence of species of the original mixtures. Recovery of autochthonous species was strongly affected by site elevation and time elapsed since restoration. Moreover, the distance of ski lanes from forest edges seems to influence the dynamics of recolonisation process. Renaturalization was remarkably faster in the lower-altitude Apennine study plot. Application of a regression analysis revealed that elevation and timespan since restoration may be considered useful predictors of the level of naturalization of the restored canopies.
Ding, Han; Zhao, Xiaohua; Rong, Jian; Ma, Jianming
The objective of this paper is to test the effectiveness and adaptability of speed reduction markings (SRMs) in downhill sections on urban roads with distinct roadway grades. Empirical data including vehicle speed and acceleration were collected in a driving simulator. Subjective questionnaires were conducted, and two indexes - the relative speed difference and standard deviation of acceleration - were developed to evaluate the effectiveness and adaptability of SRMs. Meanwhile, the effectiveness of driving simulator related to different road alignments and types of SRMs has been validated through a field test. Results of subjective questionnaires showed that the majority of subjects had no feelings of nervousness, but they were affected by SRMs while driving through downhill sections in all four scenarios (i.e., downhill sections with vertical grades of 3, 2, 1.5 and 1%). In terms of vehicle speed and acceleration, the results of the analysis of variance (ANOVA) and the contrast analysis (S-N-K method) indicated that SRMs were significantly effective when roadway grades of downgrade sections were 1.5, 2 and 3%, while transverse speed reduction markings (TSRMs) had significantly worse adaptability (P<0.05). Therefore, this research recommends that TSRMs could be placed in downhill sections with roadway grades of 1.5 or 2%; longitudinal speed reduction markings (LSRMs) could be placed in downhill sections with a roadway grade of 3%. Whether SRMs are placed in downhill sections with a roadway grade of 1% would depend on other factors such as financial issues and crash records, which are not considered in this paper. Copyright © 2014 Elsevier Ltd. All rights reserved.
Raschner, Christian; Hildebrandt, Carolin; Mohr, Johanna; Müller, Lisa
Although balance is a key ability in the strength demands of alpine ski racing, affecting both performance and injury prevention, few studies have examined balance or related sex differences among still-maturing athletes. In this 10-year study, we investigated cross-sectional balance performances at different age periods of a representative sample of over 500 11-18-year-old elite skiers of both genders. Participants performed balance tests using the MFT S3-Check. Left-right and forward-backward movements were used to calculate sensory and symmetry balance scores, which were both incorporated into a stability score. Mann-Whitney U tests assessed gender-specific differences by age-group with a significance level set at p gender differences only on forward-backward measurements for 14-16-year-olds, with females showing better stability and sensory (but not symmetry) scores than males. Thus, gender interacted with age and maturation to influence balance ability in these participants. Additionally, these rare 10-year data support coaches in their training and talent development of maturing athletes by providing important sport-, age-, and gender-specific normative comparison data for individual trainees.
Nina M. Pestereva
Full Text Available Relevance of the research of modern climate change is beyond all doubts at the moment. Climate is, first of all, a significant share of any country’s resources. Losses due to global climate change can affect virtually all branches of economy and social aspects, including energy production, eco-systems, agriculture, forests, construction, transport, tourism etc.Climate change imposes certain mode of economy, a strategy of economy’s development years ahead. According to forecasts, for example the one of European environmental agency (EEA, one of the first “hostages” of climate change will be winter tourism and alpine skiing resorts. Climate change seriously influences incomes of countries and certain regions located in mountain areas and developing winter sports.Yet, forecasts of climatologists on modern climate change trends are ambiguous and sometimes controversial. For this reason definite scientific and practical interest is raised by research in climate change trends in mountain areas based on mostly state network of meteorological stations.
Langelier, Eve; Martel, Stéphane; Millot, Anne; Lessard, Jean-Luc; Smeesters, Cécile; Rancourt, Denis
This article introduces a sit-ski developed for the Canadian Alpine Ski Team in view of the Vancouver 2010 Paralympic games. The design is predominantly based on controlling the mass distribution of the sit-ski, a critical factor in skiing performance and control. Both the antero-posterior location of the centre of mass and the sit-ski moment of inertia were addressed in our design. Our design provides means to adjust the antero-posterior centre of mass location of a sit-ski to compensate for masses that would tend to move the antero-posterior centre of mass location away from the midline of the binding area along the ski axis. The adjustment range provided is as large as 140 mm, thereby providing sufficient adaptability for most situations. The suspension mechanism selected is a four-bar linkage optimised to limit antero-posterior seat movement, due to suspension compression, to 7 mm maximum. This is about 5% of the maximum antero-posterior centre of mass control capacity (151 mm) of a human participant. Foot rest inclination was included in the design to modify the sit-ski inertia by as much as 11%. Together, these mass adjustment features were shown to drastically help athletes' skiing performance.
According to Swedish law, the reactor owner is responsible for performing a safety review and writing a ''ASAR''-report. The Nuclear Power Inspectorate (SKI) examines this report, and reports the findings to the government (the ''SKI-ASAR'' report). Each Swedish reactor should pass through three full ASAR reviews during its life-time, similar to the licensing inspection before start-up of the reactor. The first series ASAR was delivered by OKG to SKI in December 1996, and forms the basis for the SKI analysis in the present report
According to Swedish law, the reactor owner is responsible for performing a safety review and writing a ''ASAR''-report. The Nuclear Power Inspectorate (SKI) examines this report, and reports the findings to the government (the ''SKI-ASAR'' report). Each Swedish reactor should pass through three full ASAR reviews during its life-time, similar to the licensing inspection before start-up of the reactor. The first series ASAR was delivered by FKA to SKI in December 1996, and forms the basis for the SKI analysis in the present report
According to Swedish law, the reactor owner is responsible for performing a safety review and writing a so called ASAR-report. The Nuclear Power Inspectorate (SKI) examines this report, and reports the findings to the government (the so called SKI-ASAR-report). Each Swedish reactor should pass through three full ASAR reviews during its lifetime, similar to the licensing inspection before start-up of the reactor. The second series ASAR was delivered by the Ringhals utility to SKI in September 1995, and forms the basis for the SKI analysis in the present report
... Running - back pain; Weightlifting - back pain; Lumbar pain - sports; Sciatica - sports; Low back pain - sports ... MD, Thompson SR, eds. DeLee and Drez's Orthopaedic Sports Medicine: Principles and Practice . 4th ed. Philadelphia, PA: ...
... Marketplace Find an ENT Doctor Near You Facial Sports Injuries Facial Sports Injuries Patient Health Information News ... should receive immediate medical attention. Prevention Of Facial Sports Injuries The best way to treat facial sports ...
Gaucherand, S.; Evette, A.; François, H.; Paccard, P.; Perretier, C.; Wlerick, L.
This presentation is a synthesis of a symposium held last October in Cemagref, Grenoble with contributions from scientists as well as lift operators, NGO's, and administrations. In the context of global change, ski resorts must rethink their development models. The diversification of the touristic offer is encouraged and the specificity of the mountain territory is at the heart of a sustainable development. In this context, the preservation of interesting and fragile habitats such as wetlands is topical. Wetlands have many recognized functions: flooding reduction, water remediation, fertilization, biodiversity conservation… In mountain areas, wetlands are small and scattered. They are of special interest in particular for their role in biodiversity conservation and for their cultural and recreational benefits. However, in ski areas, wetlands can interact with the ski activity. Indeed, wetlands can speed up snow melting in spring and they often occupy ledges, which are strategic positions for the establishment of ski resort's facilities. The development of ski resorts can lead to the destruction or the deterioration of wetlands because of hydrologic interferences, fill in, pollution, etc. However, a few judicious steps can be taken to reduce or suppress these negative effects. In the Alps, geographical and administrative tools have been developed to help the decisions of ski-resort's administrators. Meetings between lift-operators, administrators of protected areas scientists and NGO's have also proved efficient when done at an early stage of a project, as shown by the example of the ski-resort "Les Saisies".
Jelica J. MARKOVIĆ
Full Text Available In contemporary tourism, sport and recreation are increasingly becoming the dominant motives for undertaking the journey, and as a result of modern living, active holidays are more frequent. Mountain areas have always been attractive to deal with the various sports activities. Winter sports were the initiators of the development of mountain resorts. Mountain resorts invest in construction of hotels, ski lifts, snowmaking equipment, for the sake of attracting a growing number of tourist clientele. On the other hand, sport and recreation also serve to promote summer mountain tourism. Tennis, golf, swimming, horseback riding are key tools to attract visitors in the summer months toward the resorts facilities. The main problems regarding the development of mountain tourism centers come in the form of the growing concern for the preservation of the environment, of the human and traffic congestion in the mountains and the intensive use of natural resources by tourists. This paper aims to highlight the positive and negative impacts of sport and recreation in the development of mountain tourism and to present possible solutions to reduce negative impacts. Methodology is based on document review of many bibliographic resources, which are related with skiing and mountain biking as examples of winter and summer sport activities on mountains.
The application of beta-blocking agents in endurance sports leads to deterioration of physical capacity because of negative influence of hemodynamics and metabolism. In sports with modest dynamic but high psychological strain it leads to an increase of physical capacity and decrease of stress caused by competition. The present paper summarizes changes in ski jumping, flying, motor car racing, parachute jumping, bob running and shooting. Significant decreases of heart rate, modest decreases in blood pressure as well as a reduction of occasionally appearing extrasystoles are found. Levels of glucose and lactate as well as cholesterol and triglycerides remain unchanged during beta-blockade, as do free fatty acids and free glycerol with placebo under beta-adrenolyse. Whereas ski and parachute jumpers display psychologic stress, bob runners and sport shooters were positively influenced. As a possible reason for an increased physical capacity after sympathicolysis, changes of cardiovascular parameters as well as central influences are conceivable. The application of beta-blocking agents should be regarded as "doping" because of the increases of physical capacity and should be avoided in healthy sportsmen.
Aittomaeki, A.; Maekinen, A.
The efficient use of energy is playing an increasing role in saving natural resources and in maintaining competitiveness. The system integration plays an essential role when efficiency is maximized. Expressed in thermodynamical terms the question is about minimizing the loss of energy. When planning the integration of heating and cooling the impacts of different coupling possibilities and measurements should be compared. In this report the modeling or simulation of energy balances studies in different systems is described. In the system integration of different sports buildings the modeling parts are the following: office space with heating systems, indoor ice-skating rink, skiing tunnel, indoor swimming pool, sports-field and sport center
Svoboda, Zdenek; Janura, Miroslav; Cabell, Lee; Janurová, Eva
The purpose of this study was to assess the execution of the flight phase in the Nordic combined (NC) among three groups of competitors, representing different skill levels, and to compare them with three groups of ski jumpers (SJs). Thirty NC and thirty SJ competitors, who performed ski jumps on an HS-134 m jumping hill, were divided into three subgroups based on jump length execution. Two-dimensional (2-D) kinematic data were collected from the lower extremities, trunks, and skis of the competitors. The SJ group had a smaller lower extremity angle ( p jump lengths comparable to those of the SJ competitors by having significantly higher in-run velocities.
The choice of clothing for sports must take into account the climate, movement, ability to enhance athletic performance, safety and comfort. Part 2 of this two-part article describes the clothing needed for running, cycling, skiing, windsurfing, triathlon, aerobic dancing and hot air ballooning. ImagesFig. 1Fig. 2Fig. 3Fig. 4Fig. 5Fig. 6Fig. 7Fig. 8Fig. 9Fig. 10 PMID:21274232
Gallo-Vallejo, Miguel Ángel; de la Cruz-Márquez, Juan Carlos; de la Cruz-Campos, Adrián; de la Cruz-Campos, Juan Carlos; Pestaña-Melero, Francisco Luis; Carmona-Ruiz, Ginés; Gallo-Galán, Luz María
Objective To analyse the incidence of diseases and injuries suffered by athletes participating in the 27th Winter Sports Universiade held in Granada, Spain. Methods The daily occurrence of injuries and diseases was registered at the point of first aid (Borreguiles, 2665 metres above sea level (masl)) and in the clinic of Pradollano (2017 masl), both in Sierra Nevada, as well as in medical services provided by the organising committee of Granada 2015 Universiade and located in sport pavilions in which indoor competitions are held. Results A total of 1109 athletes (650 men, 58.61%; 459 women, 41.39%). Nine diseases and 68 injuries were recorded. In total, the rate of injury was 6.13% (7.07% for men and 4.79% for women). The percentage of injury was highest in alpine skiing (10.34%) followed by freestyle skiing (8.62%). In relation to the time of exposure, freestyle skiing showed the shortest time of exposure (0.31 hours) before suffering an injury. Short track speed skating showed the longest exposure (9.80 hours), before suffering an injury. The most common anatomical areas of injury were the head, shoulder and knee (13.23%). Only nine diseases were suffered (four women and five men) of which six were infections, one was a friction burn, one was a lipothymy and one a cluster headache due to height. Conclusion In general, 6.13% of the athletes sustained at least one injury and 0.81% a disease, which is a much lower percentage than that recorded in similar events. The incidence of injuries and diseases varied among sport specialities. PMID:28879023
Matthesius, M. [Lenze GmbH und Co KG, Hameln (Germany)
The 'Alpincenter' at Bottrop is the biggest indoor winter sports center of the world. Its ventilation systems were equipped with specially selected frequency inverters. [German] Skifahren im Hochsommer? Mit dem Snowboard im Ruhrgebiet den Hang hinunter? Beste Wintersportverhaeltnisse an 365 Tagen im Jahr? Und das in Deutschland? Kein Problem. Seit Anfang des Jahres kommen in Bottrop Wintersportfreunde voll auf ihre Kosten. Nach einem halben Jahr Bauzeit hat das Alpincenter seine Pforten geoeffnet. Die Wintersporthalle ist die laengste Anlage auf der Welt. Die gesamte Belueftung wurde mit speziell auf die Klimatechnik (mit Drehzahl geregelten Ventilatoren) abgestimmten Frequenzumrichtern ausgeruestet. (orig./AKF)
Andersen, Tem Frank
This study tries to map out the possible interplay between interactive digital media (including mobile and wearable technologies) and sport as performance and participation. The ambition is to create a model providing the analytical framework for understanding questions like "are we running...
Jayanthi, Neeru; Esser, Stephen
Tennis may be considered a static and dynamic form of exercise with many well-demonstrated health benefits. Tennis has similar rates of injury to other individual recreational sports and junior competitive sports, without the catastrophic risk of contact/collision sports. Classifying tennis players into junior and elite categories versus adult recreational players may help in outlining volume of play recommendations, exposure risk, and types of injuries. Junior and elite players tend to tolerate higher volumes, have more acute and lower extremity injuries, and have more serious overuse stress injuries. Adult recreational players tend to tolerate lower volumes, have more overuse and upper extremity injuries, and more conditions that are degenerative. Many tennis players also develop asymmetric musculoskeletal adaptations, which may increase risk of specific injury. Tennis-specific evaluations may identify these at-risk segments, help guide preventive strategies including technical errors, and assist in developing return-to-play recommendations. Other racket sports such as squash, badminton, and racquetball have less data available but report both acute and traumatic injuries less commonly seen in tennis.
Clumpner, Roy A.
This book, which is primarily for secondary physical education teachers, presents a sequential approach to teaching skills that are essential to eight sports. The activities and lead-up games included in the book put beginning students directly into game-like situations where they can practice skills. Each chapter begins with a background of the…
Chapman, Robert F; Stickford, Jonathon L; Levine, Benjamin D
Winter sports events routinely take place at low to moderate altitudes, and nearly all Winter Olympic Games have had at least one venue at an altitude >1000 m. The acute and chronic effects of altitude can have a substantial effect on performance outcomes. Acutely, the decline in oxygen delivery to working muscle decreases maximal oxygen uptake, negatively affecting performance in endurance events, such as cross-country skiing and biathlon. The reduction in air resistance at altitude can dramatically affect sports involving high velocities and technical skill components, such as ski jumping, speed skating, figure skating and ice hockey. Dissociation between velocity and sensations usually associated with work intensity (ventilation, metabolic signals in skeletal muscle and heart rate) may impair pacing strategy and make it difficult to determine optimal race pace. For competitions taking place at altitude, a number of strategies may be useful, depending on the altitude of residence of the athlete and ultimate competition altitude, as follows. First, allow extra time and practice (how much is yet undetermined) for athletes to adjust to the changes in projectile motion; hockey, shooting, figure skating and ski jumping may be particularly affected. These considerations apply equally in the reverse direction; that is, for athletes practising at altitude but competing at sea level. Second, allow time for acclimatization for endurance sports: 3-5 days if possible, especially for low altitude (500-2000 m); 1-2 weeks for moderate altitude (2000-3000 m); and at least 2 weeks if possible for high altitude (>3000 m). Third, increase exercise-recovery ratios as much as possible, with 1:3 ratio probably optimal, and consider more frequent substitutions for sports where this is allowed, such as ice hockey. Fourth, consider the use of supplemental O(2) on the sideline (ice hockey) or in between heats (skating and Alpine skiing) to facilitate recovery. For competitions at sea
of the total participation from the Continents throughout the journey of the Games (1st Winter Paralympic Games: 95% - 10th Winter Paralympic Games: 61%. The proportion of men was at all events greater than that of the women. Starting with only two categories of impairment being part of the first Games (athletes with amputation and athletes visually impaired, in the 2010 Winter Paralympic Games in Vancouver, almost all categories were included (except the athletes with an intellectual disability. Conclusions : The sports included in the 1st Paralympic Games were the events of Alpine Skiing and one event of Cross Country Skiing, while in the 10th Paralympic Games were included all the disciplines of Alpine skiing and Cross-Country Skiing, Ice Sledge Hockey and Wheelchair Curling.
... many were confused by the safety requirements for paddle-skis. The future management of this fishery is discussed in light of its comparatively low impact on coastal resources. Keywords: catch and effort, fisher demographics, fisheries management, paddle-ski, recreational fishing. African Journal of Marine Science 2012, ...
Tas, Murat; Kiyici, Elif; Kiyci, Fatih
The aim of this study was to investigate the effect of skiing on the biomotoric characteristics of children with evaluating tests of girls between the ages of eight and 14 before and after the season. The experimental group of this study was 15 girls who had just started skiing and the control group of 30 girls. In total, 45 volunteers joined the…
Kangas, Katja; Tolvanen, Anne; Kälkäjä, Tarja; Siikamäki, Pirkko
Outdoor recreation and nature-based tourism represent an increasingly intensive form of land use that has considerable impacts on native ecosystems. The aim of this paper is to investigate how revegetation and management of ski runs influence soil nutrients, vegetation characteristics, and the possible invasion of nonnative plant species used in revegetation into native ecosystems. A soil and vegetation survey at ski runs and nearby forests, and a factorial experiment simulating ski run construction and management (factors: soil removal, fertilization, and seed sowing) were conducted at Ruka ski resort, in northern Finland, during 2003-2008. According to the survey, management practices had caused considerable changes in the vegetation structure and increased soil nutrient concentrations, pH, and conductivity on the ski runs relative to nearby forests. Seed mixture species sown during the revegetation of ski runs had not spread to adjacent forests. The experimental study showed that the germination of seed mixture species was favored by treatments simulating the management of ski runs, but none of them could eventually establish in the study forest. As nutrient leaching causes both environmental deterioration and changes in vegetation structure, it may eventually pose a greater environmental risk than the spread of seed mixture species alone. Machine grading and fertilization, which have the most drastic effects on soils and vegetation, should, therefore, be minimized when constructing and managing ski runs.
Kangas, Katja; Tolvanen, Anne; Kälkäjä, Tarja; Siikamäki, Pirkko
Outdoor recreation and nature-based tourism represent an increasingly intensive form of land use that has considerable impacts on native ecosystems. The aim of this paper is to investigate how revegetation and management of ski runs influence soil nutrients, vegetation characteristics, and the possible invasion of nonnative plant species used in revegetation into native ecosystems. A soil and vegetation survey at ski runs and nearby forests, and a factorial experiment simulating ski run construction and management (factors: soil removal, fertilization, and seed sowing) were conducted at Ruka ski resort, in northern Finland, during 2003-2008. According to the survey, management practices had caused considerable changes in the vegetation structure and increased soil nutrient concentrations, pH, and conductivity on the ski runs relative to nearby forests. Seed mixture species sown during the revegetation of ski runs had not spread to adjacent forests. The experimental study showed that the germination of seed mixture species was favored by treatments simulating the management of ski runs, but none of them could eventually establish in the study forest. As nutrient leaching causes both environmental deterioration and changes in vegetation structure, it may eventually pose a greater environmental risk than the spread of seed mixture species alone. Machine grading and fertilization, which have the most drastic effects on soils and vegetation, should, therefore, be minimized when constructing and managing ski runs.
This paper describes the use of computer graphics in designing part of the Sunshine Ski Area in Banff National Park. The program used was capable of generating perspective landscape drawings from a number of different viewpoints. This allowed managers to predict, and subsequently reduce, the adverse visual impacts of ski-run development. Computer graphics have proven,...
Wright, J R; Hixson, E G; Rand, J J
No studies describing the types and frequencies of nordic ski jumping injuries have been reported in the medical literature. We examined records of injuries sustained at the Intervale Ski Jump Complex (15, 40, 70, and 90 meter jumps) in Lake Placid from 1980 to 1985. Forty-seven injured jumpers sustained 72 total injuries. The most frequent injuries were contusions. Fractures occurred in 11 jumpers; most were nondisplaced. Upper extremity fractures outnumbered lower extremity fractures. Injuries requiring hospitalization were uncommon; none of these resulted in permanent disability. Injury rates for non-World Cup and for World Cup competitions were 4.3 and 1.2 injuries per 1,000 skier-days, respectively. This is roughly equivalent to injury rates in alpine skiing. Our study suggests that the dangers of nordic ski jumping have been overestimated.
Remizov, L P
The flight in a vertical plane of a ski-jumper after take-off was studied with the purpose of maximising flight distance. To solve the problem of optimal flight (how a jumper must change his angle of attack to obtain the longest jump) the basic theorem of the optimal control theory--Pontriagin's maximum principle--was applied. The calculations were based on data from wind tunnel experiments. It was shown that the maximum flight distance is achieved when the angle of attack is gradually increased according to a convex function the form of which depends on the individual aerodynamic parameters.
H Mahmoud Hasehmi
Full Text Available Nowadays, sport injuries constitute a major part of social accidents. The aim of the presentstudy, was to investigate the frequency of maxillofacial injuries among athletes-members of differentsports federations in Iran from 1998-2001. For this reason files which was related to sport injuries of men and women athletes-members of sports federations were studied in Medical Federation of the Islamic Republic of Iran Sports Organization. The information were received through 26 medical organizations,located in different states of the country. The results showed that maxillofacial injuries constitute the major part of the sports injuries. In male athletes, football was the most important cause for maxillofacial injuries. However, mountain climbing and skiing play the least role in this field. Among female athletes,karate was the cause of the highest rate of maxillofacial sport injuries. Diving, mountain climbing and skiing cause the least number of maxillofacial accidents. Nasal fracture was the most common sport injury among Iraninan male and female athletes.
Online brand community is a novel phenomenon that carries a number of benefits, but lack of clarity in antecedents of its effectiveness as a marketing alternative. Aspen/Snowmass and Breckenridge Ski Resort are two leading players in the ski industry, and this paper analyzes their activity in-depth in order to bring clarity by extracting implications on best practice. For the purpose, a tailor-made methodology is constructed. It consists of combining two analytical frameworks, interviews with...
Lima, Leonardo C R; Bassan, Natália M; Cardozo, Adalgiso C; Gonçalves, Mauro; Greco, Camila C; Denadai, Benedito S
Running economy (RE) is impaired following unaccustomed eccentric-biased exercises that induce muscle damage. It is also known that muscle damage is reduced when maximal voluntary isometric contractions (MVIC) are performed at a long muscle length 2-4 days prior to maximal eccentric exercise with the same muscle, a phenomenon that can be described as isometric pre-conditioning (IPC). We tested the hypothesis that IPC could attenuate muscle damage and changes in RE following downhill running. Thirty untrained men were randomly assigned into experimental or control groups and ran downhill on a treadmill (-15%) for 30 min. Participants in the experimental group completed 10 MVIC in a leg press machine two days prior to downhill running, while participants in the control group did not perform IPC. The magnitude of changes in muscle soreness determined 48 h after downhill running was greater for the control group (122 ± 28 mm) than for the experimental group (92 ± 38 mm). Isometric peak torque recovered faster in the experimental group compared with the control group (3 days vs. no full recovery, respectively). No significant effect of IPC was found for countermovement jump height, serum creatine kinase activity or any parameters associated with RE. These results supported the hypothesis that IPC attenuates changes in markers of muscle damage. The hypothesis that IPC attenuates changes in RE was not supported by our data. It appears that the mechanisms involved in changes in markers of muscle damage and parameters associated with RE following downhill running are not completely shared. Copyright © 2018 Elsevier B.V. All rights reserved.
A standing debate in philosophy of sport concerns whether sport can count as art in some sense. But the debate is often conducted at cross purposes. Naysayers insist that no sport is an artform while proponents insist that certain sport performances count as artworks – but these are entirely consistent claims. Both sides make unwarranted assumptions: naysayers are purists about sport and art (no transaesthetic purposes) whereas proponents are tokenists about artforms. Naysayers admit that fig...
Giandolini, Marlene; Horvais, Nicolas; Rossi, Jérémy; Millet, Guillaume Y; Samozino, Pierre; Morin, Jean-Benoît
Trail runners are exposed to a high number of shocks, including high-intensity shocks on downhill sections leading to greater risk of osseous overuse injury. The type of foot strike pattern (FSP) is known to influence impact severity and lower-limb kinematics. Our purpose was to investigate the influence of FSP on axial and transverse components of shock acceleration and attenuation during an intense downhill trail run (DTR). Twenty-three trail runners performed a 6.5-km DTR (1264m of negative elevation change) as fast as possible. Four tri-axial accelerometers were attached to the heel, metatarsals, tibia and sacrum. Accelerations were continuously recorded at 1344Hz and analyzed over six sections (~400 steps per subject). Heel and metatarsal accelerations were used to identify the FSP. Axial, transverse and resultant peak accelerations, median frequencies and shock attenuation within the impact-related frequency range (12-20Hz) were assessed between tibia and sacrum. Multiple linear regressions showed that anterior (i.e. forefoot) FSPs were associated with higher peak axial acceleration and median frequency at the tibia, lower transverse median frequencies at the tibia and sacrum, and lower transverse peak acceleration at the sacrum. For resultant acceleration, higher tibial median frequency but lower sacral peak acceleration were reported with forefoot striking. FSP therefore differently affects the components of impact shock acceleration. Although a forefoot strike reduces impact severity and impact frequency content along the transverse axis, a rearfoot strike decreases them in the axial direction. Globally, the attenuation of axial and resultant impact-related vibrations was improved using anterior FSPs. Copyright © 2016 Elsevier Ltd. All rights reserved.
Rovere, Gabriel Alejandro
The general goal of this thesis was to provide information useful for the breeding programme of the Royal Dutch Warmblood Studbook (KWPN) in relation with the ongoing specialisation of the population. Data provided by KWPN consisted of records from studbook-first inspection, competition performan....... Constructing separate selection indexes would allow for optimal weighting of information sources such as studbook-entry inspection traits in accordance to the breeding goal of each sports discipline....
Plancher, K D; Minnich, J M
Injuries to the upper extremities can happen in any sport. Injury patterns are common to specific sports. Understanding which injuries occur with these sports allows the examiner to diagnose and treat the athlete easily. This article reviews some of the injuries common in sports such as bicycling, golf, gymnastics, martial arts, racquet sports, and weightlifting.
Koen Breedveld; Rob Goossens; Maarten van Bottenburg; Wil Ooijendijk; Vincent Hildebrandt; Maarten Stiggelbout; Jo Lucassen; Hugo van der Poel
Original title: Rapportage Sport 2003. There has been a huge increase in the interest in sport in recent decades. The number of people taking part in sport has grown strongly and more sport is broadcast on television than ever before. The government has invested a great deal in sport, not
Fenerty, Lynne; Heatley, Jennifer; Young, Julian; Thibault-Halman, Ginette; Kureshi, Nelofar; Bruce, Beth S; Walling, Simon; Clarke, David B
Nova Scotia is the first jurisdiction in the world to mandate ski and snowboard helmet use for all ages at ski hills in the province. This study represents a longitudinal examination of the effects of social marketing, educational campaigns and the introduction of helmet legislation on all-age snow sport helmet use in Nova Scotia. A baseline observational study was conducted to establish the threshold of ski and snowboarding helmet use. Based on focus groups and interviews, a social marketing campaign was designed and implemented to address factors influencing helmet use. A prelegislation observational study assessed the effects of social marketing and educational promotion on helmet use. After all-age snow sport helmet legislation was enacted and enforced, a postlegislation observational study was conducted to determine helmet use prevalence. Baseline data revealed that 74% of skiers and snowboarders were using helmets, of which 80% were females and 70% were males. Helmet use was high in children (96%), but decreased with increasing age. Following educational and social marketing campaigns, overall helmet use increased to 90%. After helmet legislation was enacted, 100% compliance was observed at ski hills in Nova Scotia. Results from this study demonstrate that a multifaceted approach, including education, legislation and enforcement, was effective in achieving full helmet compliance among all ages of skiers and snowboarders. 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/
Erdmann, Wlodzimierz S; Dancewicz-Nosko, Dorota; Giovanis, Vasilios
Within several investigated endurance sport disciplines the distribution of load of the best competitors has a manner of evenly or slightly rising velocity values. Unfortunately many other competitors have usually diminishing values or when they are very poor they have evenly values. The aim of this study was to investigate distribution of velocity within 30-km cross-country female skiers. Cross-country skiing runs were investigated of Olympic Games 2002-2014 (Salt Lake City, Turin, Vancouver, Sochi). At every race two 15 km or three 10 km loops of the same vertical profile were taken into account. The competitors were divided onto: A - winners, B - medallists, C - competitors who obtained places 4 to 10 at the finish line (medium runners), D - competitors who obtained places 11 to 30 at the finish line (poor runners). Velocity data presented on the web pages of several institutions were utilized. The competitors had their velocity distributed in a manner with usually diminishing values. While comparing velocity of sequential loops with the mean velocity the difference for the poor runners reached the value of almost 6 %, which was too high. There was significant (usually negative) correlation coefficient between values of velocity deviation for the first and second loops and the mean value of velocity for the entire distance for the better runners and mixed, i.e. positive and negative values for the poorer runners. It was postulated investigations of velocity distribution should be introduced in coaching in order to inform competitors about their running. This advise is especially important for the poorer runners. Up to now cross country skiers run for themselves. It should be discussed whether the tactics used by road and track runners, i.e. running with pace makers, can be introduced in cross country skiing. Also the use of a drone during training can be used in order to maintain proper pace.
Hamada, Tomo; Matsumoto, Kazu; Ishimaru, Daichi; Sumi, Hiroshi; Shimizu, Katsuji
To examine whether child and adult skiers have different risk factors or mechanisms of injury for tibial shaft fractures. Descriptive epidemiological study. Prospectively analyzed the epidemiologic factors, injury types, and injury mechanisms at Sumi Memorial Hospital. This study analyzed information obtained from 276 patients with tibial fractures sustained during skiing between 2004 and 2012. We focused on 174 ski-related tibial shaft fractures with respect to the following factors: age, gender, laterality of fracture, skill level, mechanism of fracture (fall vs collision), scene of injury (steepness of slope), snow condition, and weather. Fracture pattern was graded according to Arbeitsgemeinschaft für Osteosynthesefragen (AO) classification and mechanical direction [external (ER) or internal rotation (IR)]. Tibial shaft fractures were the most common in both children (89.3%) and adults (47.4%). There were no significant differences in gender, side of fracture, mechanism of fracture, snow condition, or weather between children and adults. Skill levels were significantly lower in children than in adults (P differences in some of these parameters, suggesting that child and adult skiers have different risk factors or mechanisms of injury for tibial shaft fractures.
Steffen, Kathrin; Moseid, Christine Holm; Engebretsen, Lars; Søberg, Pia K; Amundsen, Olav; Holm, Kristian; Moger, Thomas; Soligard, Torbjørn
Injury and illness surveillance during high-level youth sports events is an important first step in health prevention and caretaking of the young elite athletes. To analyse injuries and illnesses that occurred during the 10 days 2nd Youth Olympic Winter Games (YOG), held in Lillehammer 2016. We recorded the daily occurrence (or non-occurrence) of injuries and illnesses through the reporting of (1) all National Olympic Committee (NOC) medical teams and (2) the polyclinic and medical venues by the Lillehammer Organising Committee (LYOCOG) medical staff. In total, 1083 athletes (48 double-starters), 46% (n=502) of them females, from 70 NOCs were registered in the study. NOCs and LYOCOG reported 108 injuries and 81 illnesses, equalling to 9.5 injuries and 7.2 illnesses per 100 athletes. The percentage of injured athletes was highest in the snowboard and ski slopestyle and cross disciplines, alpine skiing and skeleton, and lowest in the Nordic skiing disciplines. Approximately, two-thirds of the injuries (n=71, 65.7%) prevented the athlete from training or competition, while 10 injuries (9.3%) were registered with an estimated absence from sport for >7 days. The rate of illness was highest in curling and the Nordic skiing disciplines with most of them being respiratory tract infections (81.5%). Overall, 9% of the athletes incurred at least one injury during the games, and 7% an illness, which is similar to the first YOG in Innsbruck 2012 and slightly lower compared with previous Winter Olympic Games. The incidence of injuries and illnesses varied substantially between sports. 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 The aim of this study was to determine which sports are most popular among parents of pupils of primary school in Serbia, in order to determine which sports would be advisable to introduce in the classes of physical education. The sample included 5865 parents. Most parents would like to introduce as an optional sport swimming, football, basketball, volleyball and at last parents would like to introduce acrobatics, wrestling, orienteering and rowing. Obtained were statistically significant differences according to gender (fathers would like to be introduced football and mothers would like swimming and according to educational level (parents with higher educational level would most like to be introduced swimming and volleyball; while parents with the lowest educational level prefered football. The results indicates that with enlargement of educational level of parents comes higher level of interest for other sports, like skiing and basketball and decrease level interest for bicycling, football and karate.
... Videos for Educators Search English Español Dealing With Sports Injuries KidsHealth / For Teens / Dealing With Sports Injuries ... a long way toward preventing injuries. Types of Sports Injuries Common reasons why teens get injured playing ...
Sports creams are creams or ointments used to treat aches and pains. Sports cream overdose can occur if someone uses this ... Two ingredients in sports creams that can be poisonous are: Menthol Methyl salicylate
... Staying Safe Videos for Educators Search English Español Sports and Concussions KidsHealth / For Teens / Sports and Concussions ... skiers or snowboarders How Can I Prevent a Sports Concussion? Start With the Right Equipment Everyone should ...
Ingram, Anne G.
An aesthetic dimension of sport appreciation is found in the paintings and sculptures of great masters who were intrigued by the subject of sports. This article presents specifics on bringing sports art into the classroom. (Authors/JA)
Lampert, Rachel; Cannom, David; Olshansky, Brian
Safety of Sports for ICD Patients. The safety of sports participation for patients with implantable cardioverter defibrillators (ICDs) is unknown, and recommendations among physicians may vary widely. The purposes of this study were to determine current practice among patients with ICDs and their physicians regarding sports participation, and to determine how many physicians have cared for patients who have sustained adverse events during sports participation. A survey was mailed to all 1,687 U.S. physician members of the Heart Rhythm Society. Among 614 respondent physicians, recommendations varied widely. Only 10% recommended avoidance of all sports more vigorous than golf. Seventy-six percent recommended avoidance of contact, and 45% recommend avoidance of competitive sports. Most (71%) based restrictions on patients' underlying heart disease. Regardless of recommendations, most physicians (71%) reported caring for patients who participated in sports, including many citing vigorous, competitive sports, most commonly cited were basketball, running, and skiing. ICD shocks during sports were common, cited by 40% of physicians. However, few adverse consequences were reported. One percent of physicians reported known injury to patient (all but 3 minor); 5%, injury to the ICD system, and weightlifting and golf. Physician recommendations for sports participation for patients with ICDs varies widely. Many patients with ICDs do participate in vigorous and even competitive sports. While shocks were common, significant adverse events were rare.
John G. Seifert
Full Text Available Alpine slalom ski racing is a high intensity, complex sport in which racers execute turns every second. Acute fatigue can make the difference in not finishing a run (DNF or finishing out of contention. The quantity and quality of training often dictates racing success. It is not known if nutritional supplementation can improve performance in this high intensity, short duration activity. The objective of this study was to determine if ingesting a carbohydrate-protein energy gel (GEL improves finishing success and number of gates completed during 2 hr slalom sessions on two consecutive days of training. Twenty-four racers were matched; one group ingested the GEL, the second group received a liquid placebo (PLA. Total carbohy-drate, protein, and water ingested by the GEL group were 60g, 15g, and 450 mL, while the PLA group ingested 450 mL of PLA. The GEL group had significantly fewer DNF's (7/48 vs. 18/48; p = 0.02 on both days, completed a greater number of training gates on Day 2 (260.3 ± 20.1 vs. 246.3 ± 17.5 gates; p = 0.03, and had a lower RPE (3.9 ± 1.2 vs. 5.3 ± 1.2 on Day 2 (p = 0.004 vs. PLA. The statistical analysis of combined finishing times was not possible due to the high number of DNF's in the PLA group. High intensity slalom performance can be im-proved by the ingestion of an energy gel. The GEL allowed the athletes to improve training quantity and quality and their per-ception of effort was less than skiers who ingested a placebo
Bolger, Conor M; Bessone, Veronica; Federolf, Peter; Ettema, Gertjan; Sandbakk, Øyvind
The purpose of the present study was to examine the influence of increased loading of the roller ski on metabolic cost, gross efficiency, and kinematics of roller ski skating in steep and moderate terrain, while employing two incline-specific techniques. Ten nationally ranked male cross-country skiers were subjected to four 7-minute submaximal intervals, with 0, 0.5, 1.0, and 1.5 kg added beneath the roller-ski in a randomized order. This was done on two separate days, with the G2 skating at 12% incline and 7 km/h speed and G3 skating at 5% incline and 14 km/h speed, respectively. At 12% incline, there was a significant increase in metabolic rate and a decrease in gross efficiency with added weight (P0.05). No changes in cycle characteristics were observed between the different ski loadings at either incline, although the lateral and vertical displacements of the foot/skis were slightly altered at 12% incline with added weight. In conclusion, the present study demonstrates that increased loading of the ski increases the metabolic cost and reduces gross efficiency during steep uphill roller skiing in G2 skating, whereas no significant effect was revealed when skating on relatively flat terrain in G3. Cycle characteristics remained unchanged across conditions at both inclines, whereas small adjustments in the displacement of the foot coincided with the efficiency changes in uphill terrain. The increased RPE values with added ski-weight at both inclines indicates that other factors than those measured here could have influenced effort and/or fatigue when lifting a heavier ski.
Gil, Joseph A; DeFroda, Steven F; Kriz, Peter; Owens, Brett D
To examine the trend of concussions in skiers and snowboarders from 2010 to 2014; and to quantify and compare the incidence of concussions injuries in skiers and snowboarders who presented to emergency departments in the United States in 2014. Cross-sectional study of concussions in skiers and snowboarders who were evaluated in emergency departments in the United States. Incidence of concussions. The trend of the annual incidence of concussions for skiers and snowboarders remained stable from 2010 to 2014. An estimated total of 5388 skiing-related concussions and 5558 snowboarding-related concussions presented to emergency departments in the United States between January 1st, 2014, and December 31st, 2014. This represented an incidence of 16.9 concussions per 1 000 000 person-years for skiers and 17.4 concussions per 1 000 000 person-years for snowboarders. The incidence of concussions in the pediatric and young adult population of skiers was significantly higher than the incidence in the adult population. Similarly, the incidence of concussions in the pediatric and young adult population of snowboarders was significantly higher than the incidence in the adult population. The incidence of concussions was significantly higher in males compared with females in both skiing and snowboarding. The incidence of concussions from 2010 to 2014 plateaued in both skiers and snowboarders. Pediatric and young adult skiers and snowboarders had significantly higher incidences of concussion than the adult population. In contrast to the higher incidence of concussions in females in several sports including ice hockey, soccer, and basketball, the incidence of concussions was higher in males compared with females in both skiing and snowboarding.
Jordan, Matthew J; Doyle-Baker, Patricia; Heard, Mark
/chondral surgery, 60% of meniscal tears and 80% of chondral lesions had worsened since the time of primary ACLR. CONCLUSION: Concurrent injury was common in this group of elite ski racers. Primary ACL tears were typically accompanied by lateral compartment chondral lesions and complex meniscal tears that worsened...... over time. ACL/MCL tears were the most common multiligament injury pattern.......BACKGROUND: Anterior cruciate ligament (ACL) tear is the most frequent injury in alpine ski racing, and there is a high prevalence of ACL reinjury. Limited data exist on the concurrent pathology with primary ACL tears in elite alpine ski racers and the magnitude of injury progression after primary...
Müller, Lisa; Hildebrandt, Carolin; Raschner, Christian
The relative age effect (RAE), which refers to an over representation of athletes born early in a selection year, recently was proven to be present in alpine skiing. However, it was not made apparent whether the RAE exists as early as at the youngest level of youth ski racing at national level, nor whether the relative age influences racing performance. As a consequence, the purpose of the present study was twofold: first, to examine the extent of the RAE and second, to assess the influence the relative age has on the overall performance at the youngest levels of youth ski racing. The study included the investigation of 1,438 participants of the Austrian Kids Cup and 1,004 participants of the Teenager Cup at the provincial level, as well as 250 finalists of the Kids Cup and 150 finalists of the Teenager Cup at the national level. Chi²-tests revealed a highly significant RAE already at the youngest level of youth ski racing (Kids Cup) at both the provincial and national levels. There are not again favorably selected the relatively older athletes from the first into the second level of youth ski racing (Teenager Cup). Among the athletes of the Kids Cup, the relative age quarter distribution differed highly significantly from the distribution of the total sample with an over representation of relatively older athletes by comparison taking the top three positions. The data revealed that relative age had a highly significant influence on performance. This study demonstrated that the RAE poses a problem as early as the youngest level of youth ski racing, thereby indicating that many young talented kids are discriminated against, diminishing any chance they might have of becoming elite athletes despite their talents and efforts. The RAE influences not only the participation rate in alpine skiing, but also the performances. As a result, changes in the talent development system are imperative. Key pointsThe relative age influences not only the participation in youth ski
Full Text Available The indexes of bodily condition of teenagers were determined. A dynamics and increase of the explored indexes were analyzed in the process of ski preparation in the system of lessons of the physical culture of schoolchildren. The 156 teenagers at the age 11-12 years old took part in the experiment. The positive effect of ski training in the bodily condition of the investigated teenagers is proved. Reliable intercommunication was determined between the ski movements and indexes of bodily condition, which characterize work of the cardiovascular system.
Hofstätter, M.; Formayer, H.; Haas, P.
Snow reliability is the key factor to make skiing on slopes possible and to ensure added value in winter tourism. In this context snow reliability is defined by the duration of a snowpack on the ski runs of at least 50 mm snow water equivalent (SWE), within the main season (Dec-Mar). Furthermore the snowpack should form every winter and be existent early enough in season. In our work we investigate the snow reliability of six Austrian ski resorts. Because nearly all Austrian resorts rely on artificial snowmaking it is of big importance to consider man made snow in the snowpack accumulation and ablation in addition to natural snow. For each study region observed weather data including temperature, precipitation and snow height are used. In addition we differentiate up to three elevations on each site (valley, intermediate, mountain top), being aware of the typical local winter inversion height. Time periods suitable for artificial snow production, for several temperature threshold (-6,-4 or -1 degree Celsius) are calculated on an hourly base. Depending on the actual snowpack height, man made snow can be added in the model with different defined capacities, considering different technologies or the usage of additives. To simulate natural snowpack accumulation and ablation we a simple snow model, based on daily precipitation and temperature. This snow model is optimized at each site separately through certain parameterization factors. Based on the local observations and the monthly climate change signals from the climate model REMO-UBA, we generate long term time series of temperature and precipitation, using the weather generator LARS. Thereby we are not only able to simulate the snow reliability under current, but also under future climate conditions. Our results show significant changes in snow reliability, like an increase of days with insufficient snow heights, especially at mid and low altitudes under natural snow conditions. Artificial snowmaking can partly
Sharma, Vinay K.; Rango, Juan; Connaughton, Alexander J.; Lombardo, Daniel J.; Sabesan, Vani J.
Background: Since their conception during the mid-1970s, international participation in extreme sports has grown rapidly. The recent death of extreme snowmobiler Caleb Moore at the 2013 Winter X Games has demonstrated the serious risks associated with these sports. Purpose: To examine the incidence and prevalence of head and neck injuries (HNIs) in extreme sports. Study Design: Descriptive epidemiological study. Methods: The National Electronic Injury Surveillance System (NEISS) was used to acquire data from 7 sports (2000-2011) that were included in the Winter and Summer X Games. Data from the NEISS database were collected for each individual sport per year and type of HNI. Cumulative data for overall incidence and injuries over the entire 11-year period were calculated. National estimates were determined using NEISS-weighted calculations. Incidence rates were calculated for extreme sports using data from Outdoor Foundation Participation Reports. Results: Over 4 million injuries were reported between 2000 and 2011, of which 11.3% were HNIs. Of all HNIs, 83% were head injuries and 17% neck injuries. The 4 sports with the highest total incidence of HNI were skateboarding (129,600), snowboarding (97,527), skiing (83,313), and motocross (78,236). Severe HNI (cervical or skull fracture) accounted for 2.5% of extreme sports HNIs. Of these, skateboarding had the highest percentage of severe HNIs. Conclusion: The number of serious injuries suffered in extreme sports has increased as participation in the sports continues to grow. A greater awareness of the dangers associated with these sports offers an opportunity for sports medicine and orthopaedic physicians to advocate for safer equipment, improved on-site medical care, and further research regarding extreme sports injuries. PMID:26535369
Gallant, François; O'Loughlin, Jennifer L; Brunet, Jennifer; Sabiston, Catherine M; Bélanger, Mathieu
We aimed to increase understanding of the link between sport specialization during childhood and adolescent physical activity (PA). The objectives were as follows: (1) describe the natural course of sport participation over 5 years among children who are early sport samplers or early sport specializers and (2) determine if a sport participation profile in childhood predicts the sport profile in adolescence. Participants ( n = 756, ages 10-11 years at study inception) reported their participation in organized and unorganized PA during in-class questionnaires administered every 4 months over 5 years. They were categorized as early sport samplers, early sport specializers, or nonparticipants in year 1 and as recreational sport participants, performance sport participants, or nonparticipants in years 2 to 5. The likelihood that a childhood sport profile would predict the adolescent profile was computed as relative risks. Polynomial logistic regression was used to identify predictors of an adolescent sport profile. Compared with early sport specialization and nonparticipation, early sport sampling in childhood was associated with a higher likelihood of recreational participation (relative risk, 95% confidence interval: 1.55, 1.18-2.03) and a lower likelihood of nonparticipation (0.69, 0.51-0.93) in adolescence. Early sport specialization was associated with a higher likelihood of performance participation (1.65, 1.19-2.28) but not of nonparticipation (1.01, 0.70-1.47) in adolescence. Nonparticipation in childhood was associated with nearly doubling the likelihood of nonparticipation in adolescence (1.88, 1.36-2.62). Sport sampling should be promoted in childhood because it may be linked to higher PA levels during adolescence. Copyright © 2017 by the American Academy of Pediatrics.
Heimer, S; Tonković-Lojović, M
Sports medicine is a profession pertaining to primary health care of sport population (competitors, coaches, referees, participants in sports recreation). It embraces the physical and mental health protection and promotion of participants in relation to a particular sport activity and sport environment, directing athletes to a sport and adapting them to sport and the sport to them. Sports medicine takes part in selection procedure, training process planning and programming, and cares for epidemiological, hygienic, nutritional and other problems in sport. The Republic of Croatia belongs to those world states in which the field of sports medicine is regulated neither by a law or by profession. A consequence is that wide circle of physicians and paramedics work in clubs and various medical units without any legal or/and professional control not being adequately educated nor having licence for it. This review is an appeal to the Croatian Medical Chamber and the Ministry of Health to make efforts to promote the education and medical profession in sports medicine.
van der Roest, Jan Willem; Vermeulen, Jeroen; van Bottenburg, Maarten; LS Sportontw. & Managing Social Issues; UU LEG Research USG Public Matters Managing Social Issues; LS Management van Cultuur en Zingeving
This article deals with the tension between the association logic and the market logic that appears in the domain of voluntary sport clubs (VSCs). We present a qualitative analysis of sport policy texts of fifteen Dutch national sport organizations (NSOs) and the national umbrella organization to
Meile, W.; Reisenberger, E.; Brenn, G. [Graz University of Technology, Institute of Fluid Mechanics and Heat Transfer, Graz (Austria); Mayer, M. [VRVis GmbH, Vienna (Austria); Schmoelzer, B.; Mueller, W. [Medical University of Graz, Department for Biophysics, Graz (Austria)
The aerodynamic behaviour of a model ski jumper is investigated experimentally at full-scale Reynolds numbers and computationally applying a standard RANS code. In particular we focus on the influence of different postures on aerodynamic forces in a wide range of angles of attack. The experimental results proved to be in good agreement with full-scale measurements with athletes in much larger wind tunnels, and form a reliable basis for further predictions of the effects of position changes on the performance. The comparison of CFD results with the experiments shows poor agreement, but enables a clear outline of simulation potentials and limits when accurate predictions of effects from small variations are required. (orig.)
Meile, W.; Reisenberger, E.; Mayer, M.; Schmölzer, B.; Müller, W.; Brenn, G.
The aerodynamic behaviour of a model ski jumper is investigated experimentally at full-scale Reynolds numbers and computationally applying a standard RANS code. In particular we focus on the influence of different postures on aerodynamic forces in a wide range of angles of attack. The experimental results proved to be in good agreement with full-scale measurements with athletes in much larger wind tunnels, and form a reliable basis for further predictions of the effects of position changes on the performance. The comparison of CFD results with the experiments shows poor agreement, but enables a clear outline of simulation potentials and limits when accurate predictions of effects from small variations are required.
Narici, Marco; Conte, M; Salvioli, Stefano
This study investigated features of skeletal muscle ageing in elderly individuals having previously undergone unilateral total knee arthroplasty (TKA) and whether markers of sarcopenia could be mitigated by a 12-week alpine skiing intervention. Novel biomarkers agrin, indicative of neuromuscular...... junction (NMJ) degeneration, tumor suppressor protein p53, associated with muscle atrophy, and a new ultrasound-based muscle architecture biomarker were used to characterize sarcopenia. Participant details and study design are presented by Kösters et al. (2015). The results of this study show that NMJ...... degeneration is widespread among active septuagenarians previously subjected to TKA: all participants showed elevated agrin levels upon recruitment. At least 50% of individuals were identified as sarcopenic based on their muscle architecture, supporting the hypothesis that NMJ alterations precede sarcopenia...
SITE-94 is a comprehensive performance assessment exercise for a hypothetical repository for spent nuclear fuel at a real site in Sweden. SITE-94 was carried out to develop the capability and tools to enable Swedish Nuclear Power Inspectorate (SKI) to review fully the proposals for a deep repository which are expected to be made by the Swedish Nuclear Fuel and Waste Management Company, SKB (the implementor). Sweden is one of the leading countries in the research and development of geological disposal of radioactive waste. The developed methodology for performance assessment has attracted interests from other countries. The Summary of the main report of the SITE-94 project is translated here into Japanese to allow to make the information on the methodology and the related issues available among Japanese concerned. (author)
Reynolds, David Michael
This qualitative study examines the potential positive and negative socio-economic impacts that may emerge from the long-term effects of climate change on skiing-dependent businesses in Banff and Jasper National Parks, Canada. My goal was to determine whether or not skiing-related tourism in the parks in the 2020s and 2050s is more or less socio-economically vulnerable to the effects of climate change on snow cover, temperatures and ski season length at ski resorts in the parks. My study explored the level of awareness and personal perceptions of 60 skiing-dependent business managers about how the impact of climate change on ski resorts may influence future socio-economics of ski tourism businesses. I employed a vulnerability assessment approach and adopted some elements of grounded theory. My primary data sources are interviews with managers and the outcome of the geographical factors index (GFI). Supporting methods include: an analysis and interpretation of climate model data and an interpretation of the economic analysis of skiing in the parks. The interview data were sorted and coded to establish concepts and findings by interview questions, while the GFI model rated and ranked 24 regional ski resorts in the Canadian Cordillera. The findings answered the research questions and helped me conclude what the future socio-economic vulnerability may be of skiing-dependent businesses in the parks. The interviews revealed that managers are not informed about climate change and they have not seen any urgency to consider the effects on business. The GFI revealed that the ski resorts in the parks ranked in the top ten of 24 ski resorts in the Cordillera based on 14 common geographical factors. The economic reports suggest skiing is the foundation of the winter economy in the parks and any impact on skiing would directly impact other skiing-dependent businesses. Research indicates that the effects of climate change may have less economic impact on skiing
Swedish Nuclear Power Inspectorate (SKI) has reviewed the research programs 1992 of the Swedish Nuclear Fuel and Waste Management Co (SKB). This report presents the examination of the individual programs
Endrusick, Thomas; Frykman, Peter; O'Brien, Catherine; Giblo, Joseph
A traverse of the Arctic Ocean during a 2000-km unsupported ski expedition provided an opportunity to assess the impact of an extreme cold environment on the protective capabilities of a specialized footwear system (FS...
Konstantin N. Makarov
Full Text Available GeoniCS implementation for Olympic mountain skiing routes designing is considered an international standard. This program allows optimizing plan and profiling development. Besides, the author adapted the program for lines engineering protection with special metal mesh.
Andrea Rosario Proto
Full Text Available Cable cranes are among the most important means of yarding and transporting timber in many mountainous regions of Europe. In the last decade, all-terrain mobile tower cable cranes have been increasing due to their adaptability to operate both in uphill as well in downhill configuration. This research assesses the efficiency and the costs of a mobile cable crane manufactured in Czech Republic and designed for all-terrain application and specifically mounted on a wheeled agricultural tractor. A total of 100 cycle times were recorded in order to obtain evaluate the performance in the downhill as well uphill extraction configuration. The productivity analysis was based on regression equation as a function lateral distance, skyline slope distance and extracted volume. Increasing in number of lateral distance and extraction distance resulted as significant variables affecting the cycle time. Even if the test highlights a good efficiency of the extraction system for both the configuration (uphill vs downhill there a still many organisational features that could be improved in order to fully exploit the potentiality of the tested cable crane system.
Yiannakis, Andrew, Ed.; And Others
Intended for beginning and intermediate level students of sport and society, this anthology of 43 articles is organized into twelve, self-contained teaching units with unit introductions and study questions. Topics addressed include: (1) the sociological study of sport; (2) sport and American society; (3) the interdependence of sport, politics,…
Sports are a focus of millions of Americans as they attend, view, and participate in sports. The World Series, Final Four, and Super Bowl often bring back memories of fun-filled parties and celebrations, but there may be several reasons why sports are so popular in the United States. The popularity of sports, however, does not necessarily mean it…
Koen Breedveld; Carlijn Kamphuis; Annet Tiessen-Raaphorst
Original title: Rapportage sport 2008. Sport: it appeals to people; it brings people together; it promotes health; and it is profitable. Today, in 2008, sport is enjoying popularity as never before. Two-thirds of the Dutch population take part in some form of sport. After swimming and cycling,
Reid, Robert C.
Avhandling (doktorgrad) - Norges idrettshøgskole, 2010. Despite a large body of lay and professional literature covering numerous aspects of alpine skiing technique, only a limited number of published scientific investigations have examined the relationship between skier technical and tactical characteristics and racing performance. As a consequence, our scientific understanding of how the underlying mechanics of alpine ski racing technique relate to performance is surprisin...
Marcelain, Katherine; Armisen, Ricardo; Aguirre, Adam; Ueki, Nobuhide; Toro, Jessica; Colmenares, Clemencia; Hayman, Michael J
Ski is a transcriptional regulator that has been considered an oncoprotein, given its ability to induce oncogenic transformation in avian model systems. However, studies in mouse and in some human tumor cells have also indicated a tumor suppressor activity for this protein. We found that Ski−/− mouse embryo fibroblasts exhibit high levels of genome instability, namely aneuploidy, consistent with a tumor suppressor function for Ski. Time-lapse microscopy revealed lagging chromosomes and chroma...
In 1817 on the University of Vilnius Faculty of Medicine, T. A. Wołkowiński, a student of the eminent clinician Józef Frank, defended his doctor's degree thesis about a direct relation between rheumatic disease and cardiomegaly. It was probably the first paper in Poland describing with details the rheumatic heart disease. Unfortunately we don't know much about T. A. Wołkowiński's life.
Ulaga, Maja; Čoh, Milan; Jošt, Bojan
The aim of the study was to establish the validity of the dimensional configuration of the reduced po-tential performance model in ski jumping. Two performance models were prepared (models A and B), dif-fering only in terms of their method of determining the weights (dimensional configuration). Model A in-volves the dependent determination of weights while model B includes the independent determination of weights. The sample consisted of 104 Slovenian ski jumpers from the senior-men’s categor...
Full Text Available Alpine skiing, both recreational and competitive, is associated with high rates of injury. Numerous studies have shown that occupational exposure to whole-body vibrations is strongly related to lower back pain and some suggest that, in particular, vibrations of lower frequencies could lead to overuse injuries of the back in connection with alpine ski racing. However, it is not yet known which forms of skiing involve stronger vibrations and whether these exceed safety thresholds set by existing standards and directives. Therefore, this study was designed to examine whole-body vibrations connected with different types of skiing and the associated potential risk of developing low back pain. Eight highly skilled ski instructors, all former competitive ski racers and equipped with five accelerometers and a Global Satellite Navigation System to measure vibrations and speed, respectively, performed six different forms of skiing: straight running, plowing, snow-plow swinging, basic swinging, short swinging, and carved turns. To estimate exposure to periodic, random and transient vibrations the power spectrum density (PSD and standard ISO 2631-1:1997 parameters [i.e., the weighted root-mean-square acceleration (RMS, crest factor, maximum transient vibration value and the fourth-power vibration dose value (VDV] were calculated. Ground reaction forces were estimated from data provided by accelerometers attached to the pelvis. The major novel findings were that all of the forms of skiing tested produced whole-body vibrations, with highest PSD values of 1.5–8 Hz. Intensified PSD between 8.5 and 35 Hz was observed only when skidding was involved. The RMS values for 10 min of short swinging or carved turns, as well as all 10-min equivalent VDV values exceeded the limits set by European Directive 2002/44/EC for health and safety. Thus, whole-body vibrations, particularly in connection with high ground reaction forces, contribute to a high risk for low back
Maciejczyk, Marcin; Więcek, M; Szymura, J; Szyguła, Z
The purpose of this study was to compare the physiological and the acid-base balance response to running at various slope angles. Ten healthy men 22.3 ± 1.56 years old participated in the study. The study consisted of completing the graded test until exhaustion and three 45-minute runs. For the first 30 minutes, runs were performed with an intensity of approximately 50% VO2max, while in the final 15 minutes the slope angle of treadmill was adjusted (0°; +4.5°; -4.5°), and a fixed velocity of running was maintained. During concentric exercise, a significant increase in the levels of physiological indicators was reported; during eccentric exercise, a significant decrease in the level of the analyzed indicators was observed. Level running did not cause significant changes in the indicators of acid-base balance. The indicators of acid-base balance changed significantly in the case of concentric muscle work (in comparison to level running) and after the eccentric work, significant and beneficial changes were observed in most of the biochemical indicators. The downhill run can be used for a partial regeneration of the body during exercise, because during this kind of effort an improvement of running economy was observed, and this type of effort did not impair the acid-base balance of body.
Full Text Available With the energy consumption rising in rail transport, the railway sector is showing increasing interest in the energy-efficient operation of freight trains. Freight trains require more complicated driving strategies than ordinary passenger trains do due to their heavy loads, especially in the long-distance steep downhill (LDSD sections that are very common in freight rail lines in China. This paper studies the energy-efficient operation of a freight train considering LDSD sections. An optimal control model including regenerative and pneumatic braking is developed for the freight train. Then, when a train leaves/enters the LDSD section, we verify the uniqueness of control transitions and discuss the speed profile linkage between LDSD and its adjacent sections, which indicates that the periodic braking should be applied on LDSD sections for optimality. Additionally, given the same running time for the entire journey, our analysis shows that electrical braking-full braking strategy is more energy-efficient than coasting-full braking strategy on LDSD sections. Finally, a numerical algorithm for the optimal driving solution is proposed. The simulation results demonstrate that the driving strategies generated by the proposed algorithm performs better than those from fuzzy predictive control and field operation regarding energy saving.
Koen Breedveld; Rob Goossens; Maarten van Bottenburg; Wil Ooijendijk; Vincent Hildebrandt; Maarten Stiggelbout; Jo Lucassen; Hugo van der Poel
Original title: Rapportage Sport 2003. There has been a huge increase in the interest in sport in recent decades. The number of people taking part in sport has grown strongly and more sport is broadcast on television than ever before. The government has invested a great deal in sport, not least because of the growing awareness of the positive effect that sport can have on health, social cohesion and the economy. Sport is now an integral part of society and has developed into the biggest infor...
Wiesinger, Hans-Peter; Rieder, Florian; Kösters, Alexander; Müller, Erich; Seynnes, Olivier R
Introduction: During running and jumping activities, elastic energy is utilized to enhance muscle mechanical output and efficiency. However, training-induced variations in tendon spring-like properties remain under-investigated. The present work extends earlier findings on sport-specific profiles of tendon stiffness and cross-sectional area to examine whether years of distinct loading patterns are reflected by tendons' ability to store and return energy. Methods: Ultrasound scans were performed to examine the morphological features of knee extensor and plantar flexor muscle-tendon units in elite ski jumpers, distance runners, water polo players, and sedentary controls. Tendon strain energy and hysteresis were measured with combined motion capture, ultrasonography, and dynamometry. Results: Apart from the fractional muscle-to-tendon cross-sectional area ratio being lower in the knee extensors of ski jumpers (-31%) and runners (-33%) than in water polo players, no difference in the considered muscle-tendon unit morphological features was observed between groups. Similarly, no significant difference in tendon energy storage or energy return was detected between groups. In contrast, hysteresis was lower in the patellar tendon of ski jumpers (-33%) and runners (-30%) compared to controls, with a similar trend for the Achilles tendon (significant interaction effect and large effect sizes η 2 = 0.2). Normalized to body mass, the recovered strain energy of the patellar tendon was ~50% higher in ski jumpers than in water polo players and controls. For the Achilles tendon, recovered strain energy was ~40% higher in ski jumpers and runners than in controls. Discussion: Advantageous mechanical properties related to tendon spring-like function are observed in elite athletes whose sport require effective utilization of elastic energy. However, the mechanisms underpinning the better tendon capacity of some athletes to retain elastic energy could not be ascribed to intrinsic or
Schmölzer, B; Müller, W
Many contemporary world class ski jumpers are alarmingly underweight and several cases of anorexia nervosa have come to light. Athletes strive for low body weight because it gives them a major competitive advantage. In order to stop this hazardous development, changes to the regulations are being discussed, and the International Ski Federation and the International Olympic Committee wish to be proactive in safe guarding the interest of the athletes and their health. This study of ski jumping uses field studies conducted during World Cup competitions, large-scale wind tunnel measurements with 1:1 models of ski jumpers in current equipment and highly accurate computer simulations of the flight phase that include the effects due to the athlete's position changes. Particular attention has been directed to the design of a reference jump that mirrors current flight style and equipment regulations (2001), and to the investigation of effects associated with variation in body mass, air density, and wind gusts during the simulated flight. The detailed analysis of the physics of ski jumping described here can be used for the investigation of all initial value and parameter variations that determine the flight path of a ski jumper and will form a reliable basis for setting regulations that will make it less attractive or even disadvantageous for the athlete to be extremely light.
Chardonnens, Julien; Favre, Julien; Cuendet, Florian; Gremion, Gérald; Aminian, Kamiar
Dynamics is a central aspect of ski jumping, particularly during take-off and stable flight. Currently, measurement systems able to measure ski jumping dynamics (e.g. 3D cameras, force plates) are complex and only available in few research centres worldwide. This study proposes a method to determine dynamics using a wearable inertial sensor-based system which can be used routinely on any ski jumping hill. The system automatically calculates characteristic dynamic parameters during take-off (position and velocity of the centre of mass perpendicular to the table, force acting on the centre of mass perpendicular to the table and somersault angular velocity) and stable flight (total aerodynamic force). Furthermore, the acceleration of the ski perpendicular to the table was quantified to characterise the skis lift at take-off. The system was tested with two groups of 11 athletes with different jump distances. The force acting on the centre of mass, acceleration of the ski perpendicular to the table, somersault angular velocity and total aerodynamic force were different between groups and correlated with the jump distances. Furthermore, all dynamic parameters were within the range of prior studies based on stationary measurement systems, except for the centre of mass mean force which was slightly lower.
Virmavirta, Mikko; Isolehto, Juha; Komi, Paavo; Brüggemann, Gert-Peter; Müller, Erich; Schwameder, Hermann
Early flight phase (approximately 40 m) of the athletes participating in the final round of the individual large hill ski jumping competition in Salt Lake City Olympics was filmed with two high-speed pan & tilt video cameras. The results showed that jumpers' steady flight position was almost completed within 0.5s. The most significant correlation with the length of the jump was found in the angle between the skis and body (r=.714, p.001 at 1.1s after the take-off). This particular phase seemed to be important because the ski angle of attack was also related to the jumping distance at the same phase. Although the more upright ski position relative to flight path resulted in longer jumping distance, the winner of the competition had significantly lower ski position as compared to the other good jumpers. This may be due to the high altitude (>2000 m) of the ski jumping stadium in this competition. Because of the low air density, the aerodynamic forces were also low and this probably caused less skillful jumpers to lean too much forward at this phase. Maintenance of speed seemed to be emphasized in this particular competition.
Liu Xia; Li Ping; Zhang En; Liu Ping; Zhou Ping; Zhou Yuanguo
Objective: To examine radioprotective effect of c-ski on rat skin fibroblast in vitro and explore its possible mechanism. Methods: The effect of soft X-ray irradiation at dose varied from 2 to 8 Gy on cell apoptosis in rat skin fibroblast were determined by flow cytometry with Annexin-V-FITC-PI labelling. The effect of c-ski gene transfection on cell apoptosis was evaluated after soft X-ray irradiation of 4 Gy. The protein expressions of Bax and Bcl-2 after c-ski gene transfection were measured with the Western blot method. Results: Soft X-ray irradiation increases cell apoptosis, and the increase is proportional to the irradiation dose. Apoptosis ratio increases with time since the irradiation, and reaches its peak at 36h after the irradiation, c-ski gene was observed to markedly decrease apoptosis index at 24 h after soft X-ray irradiation of 4 Gy compared to the control group, significant increase of the protein expression of Bcl-2 was observed. C-ski gene was found no significant effect on the protein expression of Bax. Conclusion: c-ski gene can decrease radiation sensitivity of skin fibroblast, promoting Bcl-2 protein expression is one of its possible mechanism for this radioprotective effects. (authors)
Ski centres are characterized by significant environmental impacts that occur during both the construction and the operation phase. In Trentino, a well-known ski destination located in northern Italy, new ski areas were identified by planning tools without conducting a formal assessment of their effects on the environment. This paper presents a study to assess and compare the impacts of the proposed ski areas within two valleys strongly linked to winter tourism: the Fiemme and Fassa Valleys. The method is based on the computation of spatial indicators using a Geographical Information System (GIS) to predict and quantify critical impacts, such as ecosystem loss and fragmentation, soil erosion, geomorphologic hazards, interference with flora and fauna, and visibility. Subsequently, multicriteria analysis was applied to generate composite indices, and to rank ski areas according to their overall suitability. Finally, sensitivity analyses allowed to test the stability of the results. The study concluded that two of the proposed ski areas are located in highly unsuitable environment, and the relevant plan provisions should be revised
Ruedl, G; Pocecco, E; Wolf, M; Schöpf, S; Burtscher, M; Kopp, M
With the recent worldwide increase in ski helmet use, new market trends are developing, including audio helmets for listening to music while skiing or snowboarding. The aim of this study was to evaluate whether listening to music with an audio ski helmet impairs reaction time to peripheral stimuli. A within-subjects design study using the Compensatory-Tracking-Test was performed on 65 subjects (36 males and 29 females) who had a mean age of 23.3 ± 3.9 years. Using repeated measures analysis of variance, we found significant differences in reaction times between the 4 test conditions (p=0.039). The lowest mean reaction time (± SE) was measured for helmet use while listening to music (507.9 ± 13.2 ms), which was not different from helmet use alone (514.6 ± 12.5 ms) (p=0.528). However, compared to helmet use while listening to music, reaction time was significantly longer for helmet and ski goggles used together (535.8 ± 14.2 ms, p=0.005), with a similar trend for helmet and ski goggles used together while listening to music (526.9 ± 13.8 ms) (p=0.094). In conclusion, listening to music with an audio ski helmet did not increase mean reaction time to peripheral stimuli in a laboratory setting. © Georg Thieme Verlag KG Stuttgart · New York.
Full Text Available Coupled bending-torsion vibrations at the shovel are a severe problem when running an alpine ski at high velocities on hard or icy slopes. Thus, a major goal for ski manufacturers is to dampen vibrations through a proper multi-material design and/or additional absorbers. The aim of this study was to examine the effectiveness of a particular vibration absorber on a commercial slalom ski through a series of laboratory tests as well as a subjective field evaluation. Therefore, two identical pairs of ski were used and the absorber was deactivated on one pair. Laboratory tests revealed reductions of 5% to 49% of bending vibrations on skis with activated absorber. Subjective evaluation by 6 subjects suggested minor differences in the mean of the evaluated criteria turnablity, edge grip, steering behavior and stability towards a better performance of the skis with activated absorber. Subjects were able to identify the absorber mode with a success rate of 61.1%.
Allen, Martin; McKenzie, Richard
Personal erythemal UV monitoring badges, which were developed to monitor the UV exposure of school children, were used to measure UV exposures received by one of the authors (MA) at the Mt Hutt ski-field, in New Zealand. These were then compared with measurements taken at the same times from a nearby sea level site in Christchurch city. The badges were designed to give instantaneous readings of erythemally-weighted (i.e., "sun burning") UV radiation and were cross-calibrated against meteorological grade UV instruments maintained by the National Institute of Water & Atmospheric Research (NIWA). All skiing and calibration days were clear and almost exclusively cloud free. It was found that the UV maxima for horizontal surfaces at the ski-field (altitude approximately 2 km) were 20-30% greater than at the low altitude site. Larger differences between the sites were observed when the sensor was oriented perpendicular to the sun. The personal doses of UV received by a sensor on the skier's lapel during two days of skiing activity were less than those received by a stationary detector on a horizontal surface near sea level. The exposures depended strongly on the time of year, and in mid-October the maximum UV intensity on the ski-field was 60% greater than in mid-September. The UV exposure levels experienced during skiing were smaller than the summer maxima at low altitudes.
Full Text Available This paper deals with the subject of injury in alpine skiing and snowboarding and the aim was to define the characteristics of injuries and the risk factors as the basis for establishing preventive measures. The types of injuries and risk factors were analyzed by examining previous papers. During the last thirty years, the number of injuries has generally decreased by 50-70%. The changes were recorded in the types of injuries, and the number of certain injuries increased. It was found that there was a mutual difference in the number and structure of the injuries of skiers and snowboarders. Injuries can be classified topologically and according to risk factors. The risk factors may be manifold: the characteristics of the equipment, the characteristics of the trail and snow surface, protective equipment, age, gender, physical fitness, risky behaviours, time of day, skiing discipline, climate factors, the presence of other skiers and others. By the analysis of these factors it was concluded that there were three entities in the implementation of security measures: the state that stipulates laws (relevant ministries, owners or organizers who provide services in skiing (ski centres, ski services, ski schools, clubs and skiers and snowboarders themselves.
Myer, Gregory D.; Jayanthi, Neeru; Difiori, John P.; Faigenbaum, Avery D.; Kiefer, Adam W.; Logerstedt, David; Micheli, Lyle J.
Context: There is increased growth in sports participation across the globe. Sports specialization patterns, which include year-round training, participation on multiple teams of the same sport, and focused participation in a single sport at a young age, are at high levels. The need for this type of early specialized training in young athletes is currently under debate. Evidence Acquisition: Nonsystematic review. Study Design: Clinical review. Level of Evidence: Level 4. Conclusion: Sports sp...
Hwang, Kun; You, Sun Hye; Lee, Hong Sik
In this paper, we report a retrospective study of 236 patients with facial bone fractures from various sports who were treated at the Department of Plastic and Reconstructive Surgery, Inha University Hospital, Incheon, South Korea, between February 1996 and April 2007. The medical records of these patients were reviewed and analyzed to determine the clinical characteristics and treatment of the sports-related facial bone fractures. The highest frequency of sports-related facial bone fractures was in the age group 11 to 20 years (40.3%); there was a significant male predominance in all age groups (13.75:1). The most common causes of the injury were soccer (38.1%), baseball (16.1%), basketball (12.7%), martial arts (6.4%), and skiing or snowboarding (11%). Fractures of the nasal bone were the most common in all sports; mandible fractures were common in soccer and martial arts, orbital bone fractures were common in baseball, basketball, and ice sports, and fractures of the zygoma were frequently seen in soccer and martial arts. The main causes of the sports injuries were direct body contact (50.8%), and the most commonly associated soft tissue injuries were found in the head and neck regions (92.3%). Nasal bone fractures were the most common (54.2%), and tripod fractures were the most common type of complex injuries (4.2%). The complication rate was 3.0%. Long-term epidemiological data regarding the natural history of sports-related facial bone fractures are important for the evaluation of existing preventative measures and for the development of new methods of injury prevention and treatment.
Sport is becoming an activity of increasing importance: over time more people participate in sport (active sport consumption), more time is spent watching sport (passive sport consumption). An important part of sport consumption is passive sport consumption where production and consumption are
Kim, S.; Park, J. H.; Lee, D. K.
The purpose of this study is to predict changes in the operation of ski slopes due to climate change and offer meaningful implications that the ski industry can refer to when preparing to address climate change. All 17 ski resorts in South Korea were selected as study sites. To determine the weather and managerial conditions for the operation of ski slopes, interviews with operators and a review of past weather and operational conditions were conducted. To project future changes in the season of operation for ski slopes, future weather data for the 2030s, 2060s, and 2090s from RCP scenarios were adapted to the conditions for the operation of ski slopes.The study found that the artificial snowmaking begins when the temperature reaches -2 °C, the slope is opened 9 days after artificial snowmaking starts, and the slope is closed when the temperature reaches 0 °C. By applying future weather data to these conditions, it is estimated that the ski season will decrease in the future as follows: from around 130 days at present to around 120 days based on RCP 2.0 and RCP 6.0, around 130 days based on RCP 4.5, and 90 days based on RCP 8.5 in the areas where the average temperature of the ski season is below -2 °C; from around 120 days at present to around 120 days based on RCP 2.0 and 4.5, around 100-days based on RCP 6.0, and 60 days based on RCP 8.5 in the areas where the average temperature of the ski season is below 0 °C; from around 90 days at present to around 80 days based on RCP 2.0, around 90 days based on RCP 4.5, around 50 days based on RCP 6.0, and 10 days based on RCP 8.5 in the areas where the average temperature of the ski season is above 0 °C. In addition, it is also estimated that in the 2090s, 16 of 17 ski resorts can survive based on RCP 2.6 and RCP 4.5, 13 ski resorts can survive based on RCP 6.0, and none of the resorts can survive based on RCP 8.5, according to the 100-days rule, which is the minimum required duration of the operation of ski resorts
Mohtadi, Nicholas G; Chan, Denise S
Physicians counseling athletes on the prognosis of sport-specific performance outcomes after anterior cruciate ligament reconstruction (ACLR) depend on the published literature. However, critical appraisal of the validity and biases in these studies is required to understand how ACLR affects an athlete's ability to return to sport, the athlete's sport-specific performance, and his or her ability to achieve preinjury levels of performance. This review identifies the published prognostic studies evaluating sport-specific performance outcomes after ACLR. A risk of bias assessment and summaries of return to sport and career longevity results are provided for each included study. Systematic review. Electronic databases (Ovid MEDLINE, EMBASE, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, and PUBMED) were searched via a defined search strategy with no limits, to identify relevant studies for inclusion in the review. A priori defined eligibility criteria included studies measuring sport-specific performance within an athlete's sport, before and after primary ACLR. Reference lists of eligible studies were hand-searched for additional relevant studies. Data extraction was performed by use of a standardized spreadsheet. Each included study was assessed by use of 6 bias domains of the Quality in Prognosis Studies tool to critically appraise study participation, study attrition, prognostic factors, outcome measurement, confounders, and statistical analysis and reporting. Two authors independently performed each stage of the review and reached consensus through discussion. Fifteen pertinent prognostic studies evaluated sport-specific performance outcomes and/or return to play after ACLR for athletes participating in competitive soccer, football, ice hockey, basketball, Alpine ski, X-Games ski and snowboarding, and baseball. Twelve of these studies were considered to have a high level of bias. This review demonstrated that most high
Full Text Available Management applied in sport contributes to achieving full functionality of sports structures, the large masses of people, a plurality of means and skills, objectives and intentions. Through the efforts of management in sport individuals or groups of people are coordinated towards achieving a common goal, complicated and difficult process due to concerns divergent which always, through his, they are converted into cutting issues ensuring mobility objectives. Sports management helps to master and control both situations and complex systems ensuring permanent and continuous management of a multitude of sporting activities generating efficiency. Particularities of management in sport resides in that it applies to all forms of sports, all sports disciplines, which provides an organized leading to superior results in sporting competitions.
Christensen, Mette Krogh
dealing with anonymous individuals, whose anonymity results from the confidentiality requirements of a social scientific research methodology, to those leaning more towards the literary-historical traditions of 'conventional' biographical writing. However, these examples are polar extremes and none...... in the academis world of sport studies. It does not set out to be a methodological treatise but through the writing of lives in sports does raise questions of method. Each essay in this collection deals with problems of writing sports-people's lives. These essays could be said to fall along a spectrum from those......Writing lives in sport is a book of stories about sports-persons. The people concerned include sports stars, sports people who are not quite so famous, and relatively unknown physical education teachers and sports scientists.Writing lives in sport raises questions about writing biographies...
According to Swedish law, the reactor owner is responsible for performing a safety review and writing a so called ASAR-report. The Nuclear Power Inspectorate (SKI) examines this report, and reports the findings to the government (the so called SKI-ASAR-report). Each Swedish reactor should pass through three full ASAR reviews during its lifetime, similar to the licensing inspection before start-up of the reactor. The second series ASAR was delivered by the Barsebaeck utility to SKI in September 1995, and forms the basis for the SKI analysis in the present report
Pesado, Cristina; Pons, Marc; Vilella, Marc; López-Moreno, Juan Ignacio
The Pyrenees host one of the largest ski area in Europe after the Alps that encompasses the mountain area of the south of France, the north of Spain and the small country of Andorra. In this region, winter tourism is one of the main source of income and driving force of local development on these mountain communities. However, this activity was identified as one of the most vulnerable to a future climate change due to the projected decrease of natural snow and snowmaking capacity. However, within the same ski resorts different areas showed to have a very different vulnerability within the same resort based on the geographic features of the area and the technical management of the slopes. Different areas inside a same ski resort could have very different vulnerability to future climate change based on aspect, steepness or elevation. Furthermore, the technical management of ski resorts, such as snowmaking and grooming were identified to have a significant impact on the response of the snowpack in a warmer climate. In this line, two different ski resorts were deeply analyzed taken into account both local geographical features as well as the effect of the technical management of the runs. Principal Component Analysis was used to classify the main areas of the resort based on the geographic features (elevation, aspect and steepness) and identify the main representative areas with different local features. Snow energy and mass balance was simulated in the different representative areas using the Cold Regions Hydrological Model (CRHM) assuming different magnitudes of climate warming (increases of 2°C and 4°C in the mean winter temperature) both in natural conditions and assuming technical management of the slopes. Theses first results showed the different sensitivity and vulnerability to climate changes based on the local geography of the resort and the management of the ski runs, showing the importance to include these variables when analyzing the local vulnerability
Full Text Available The relative age effect (RAE, which refers to an over representation of athletes born early in a selection year, recently was proven to be present in alpine skiing. However, it was not made apparent whether the RAE exists as early as at the youngest level of youth ski racing at national level, nor whether the relative age influences racing performance. As a consequence, the purpose of the present study was twofold: first, to examine the extent of the RAE and second, to assess the influence the relative age has on the overall performance at the youngest levels of youth ski racing. The study included the investigation of 1,438 participants of the Austrian Kids Cup and 1,004 participants of the Teenager Cup at the provincial level, as well as 250 finalists of the Kids Cup and 150 finalists of the Teenager Cup at the national level. Chi²-tests revealed a highly significant RAE already at the youngest level of youth ski racing (Kids Cup at both the provincial and national levels. There are not again favorably selected the relatively older athletes from the first into the second level of youth ski racing (Teenager Cup. Among the athletes of the Kids Cup, the relative age quarter distribution differed highly significantly from the distribution of the total sample with an over representation of relatively older athletes by comparison taking the top three positions. The data revealed that relative age had a highly significant influence on performance. This study demonstrated that the RAE poses a problem as early as the youngest level of youth ski racing, thereby indicating that many young talented kids are discriminated against, diminishing any chance they might have of becoming elite athletes despite their talents and efforts. The RAE influences not only the participation rate in alpine skiing, but also the performances. As a result, changes in the talent development system are imperative.
Patel, Dilip R; Stier, Bernhard; Luckstead, Eugene F
Sports are part of the sociocultural fabric of all countries. Although different sports have their origins in different countries, many sports are now played worldwide. International sporting events bring athletes of many cultures together and provide the opportunity not only for athletic competition but also for sociocultural exchange and understanding among people. This article reviews five major sports with international appeal and participation: cricket, martial arts, field hockey, soccer, and tennis. For each sport, the major aspects of physiological and biomechanical demands, injuries, and prevention strategies are reviewed.
..., 2013; and the offices of the Forest Service's Lake Tahoe Basin Management Unit, 35 College Drive, in... Sports Program Manager, Recreation, Heritage, and Volunteer Resources Staff, at 801- 975-3793... 800-877-8339 between 8:00 a.m. and 8:00 p.m., Eastern Daylight Time, Monday through Friday. Dated...
Wang, Hao; Zhang, Xue; Jiang, Zhuoling; Wang, Yongfeng; Hou, Shimin
Electron confinement in fractal Sierpiński triangles (STs) on Ag(111) is investigated using scanning tunneling spectroscopy and theoretically simulated by employing an improved two-dimensional (2D) multiple scattering theory in which the energy-dependent phase shifts are explicitly calculated from the electrostatic potentials of the molecular building block of STs. Well-defined bound surface states are observed in three kinds of triangular cavities with their sides changing at a scale factor of 2. The decrease in length of the cavities results in an upshift of the resonances that deviates from an expected inverse quadratic dependence on the cavity length due to the less efficient confinement of smaller triangular cavities. Differential conductance maps at some specific biases present a series of alternative bright and dark rounded triangles preserving the symmetry of the boundary. Our improved 2D multiple scattering model reproduces the characteristics of the standing wave patterns and all features in the differential conductance spectra measured in experiments, illustrating that the elastic loss boundary scattering dominates the resonance broadening in these ST quantum corrals. Moreover, the self-similar structure of STs, that a larger central cavity is surrounded by three smaller ones with a half side length, gives rise to interactions of surface states confined in neighboring cavities, which are helpful for the suppression of the linewidth in differential conductance spectra.
Winkler, Ethan A; Yue, John K; Burke, John F; Chan, Andrew K; Dhall, Sanjay S; Berger, Mitchel S; Manley, Geoffrey T; Tarapore, Phiroz E
OBJECTIVE Sports-related traumatic brain injury (TBI) is an important public health concern estimated to affect 300,000 to 3.8 million people annually in the United States. Although injuries to professional athletes dominate the media, this group represents only a small proportion of the overall population. Here, the authors characterize the demographics of sports-related TBI in adults from a community-based trauma population and identify predictors of prolonged hospitalization and increased morbidity and mortality rates. METHODS Utilizing the National Sample Program of the National Trauma Data Bank (NTDB), the authors retrospectively analyzed sports-related TBI data from adults (age ≥ 18 years) across 5 sporting categories-fall or interpersonal contact (FIC), roller sports, skiing/snowboarding, equestrian sports, and aquatic sports. Multivariable regression analysis was used to identify predictors of prolonged hospital length of stay (LOS), medical complications, inpatient mortality rates, and hospital discharge disposition. Statistical significance was assessed at α sports-related TBIs were documented in the NTDB, which represented 18,310 incidents nationally. Equestrian sports were the greatest contributors to sports-related TBI (45.2%). Mild TBI represented nearly 86% of injuries overall. Mean (± SEM) LOSs in the hospital or intensive care unit (ICU) were 4.25 ± 0.09 days and 1.60 ± 0.06 days, respectively. The mortality rate was 3.0% across all patients, but was statistically higher in TBI from roller sports (4.1%) and aquatic sports (7.7%). Age, hypotension on admission to the emergency department (ED), and the severity of head and extracranial injuries were statistically significant predictors of prolonged hospital and ICU LOSs, medical complications, failure to discharge to home, and death. Traumatic brain injury during aquatic sports was similarly associated with prolonged ICU and hospital LOSs, medical complications, and failure to be discharged to
Describes an exhibition (originating at the Smithsonian Institution) which celebrates athletes and sports-related figures who became legends in their own time. Information is presented on art works, sports memorabilia, advertising posters, and photographs. (AM)
In spring 2013, the regional directorate for youth, sports and social cohesion and the regional healthcare agency in Franche-Comté presented and signed the first regional health, sports and well-being plan.
chapters on the benefits of exercise, sports for older persons and those with disabilities, sports physiotherapy, exercise psychology and medical coverage for major events. The stated ... practice will be aware of an increasing reluctance on the.
Stillhard, Angela; Buschor, Cornel; Krastl, Gabriel; Kühl, Sebastian; Filippi, Andreas
This study investigates the frequency of injuries, in particular dental injuries, among ski jumpers and Nordic combined athletes. It also examines the level of knowledge regarding tooth protection and tooth rescue boxes in this population. Of the 465 sportswomen and sportsmen who took part in the study, 230 (62.5%) of the 368 ski jumpers and 56 (56.5%) of the 97 Nordic combined athletes had sustained an injury. In both disciplines injury was most likely among professionals. The survey participants reported injuries to the limbs (n = 216), head and lips (n = 273 and n = 253, respectively), torso or spine (n = 249), teeth (n = 246), nose (n = 229) and jaw (n = 26). Dental injuries were more common among professionals than either amateur or junior ski jumpers, whereas, among the Nordic combined athletes, juniors were most likely to sustain a dental injury. Overall, the frequency of dental injury was significantly (p = 0.019) higher among adults 12.7% (n = 234) than junior athletes 6.1% (n = 212). The level of awareness of mouthguards and tooth rescue boxes varied between countries. The high injury rate recorded in this study demonstrates that ski jumping contains a considerable risk of injury, including tooth damage. Consequently, it seems reasonable to inform skiing organisations, trainers and athletes about the potential benefits of mouthguards and tooth rescue boxes in order to reduce the risk of dental injury.
Carmignac, Virginie; Thevenon, Julien; Adès, Lesley; Callewaert, Bert; Julia, Sophie; Thauvin-Robinet, Christel; Gueneau, Lucie; Courcet, Jean-Benoit; Lopez, Estelle; Holman, Katherine; Renard, Marjolijn; Plauchu, Henri; Plessis, Ghislaine; De Backer, Julie; Child, Anne; Arno, Gavin; Duplomb, Laurence; Callier, Patrick; Aral, Bernard; Vabres, Pierre; Gigot, Nadège; Arbustini, Eloisa; Grasso, Maurizia; Robinson, Peter N; Goizet, Cyril; Baumann, Clarisse; Di Rocco, Maja; Sanchez Del Pozo, Jaime; Huet, Frédéric; Jondeau, Guillaume; Collod-Beroud, Gwenaëlle; Beroud, Christophe; Amiel, Jeanne; Cormier-Daire, Valérie; Rivière, Jean-Baptiste; Boileau, Catherine; De Paepe, Anne; Faivre, Laurence
Shprintzen-Goldberg syndrome (SGS) is characterized by severe marfanoid habitus, intellectual disability, camptodactyly, typical facial dysmorphism, and craniosynostosis. Using family-based exome sequencing, we identified a dominantly inherited heterozygous in-frame deletion in exon 1 of SKI. Direct sequencing of SKI further identified one overlapping heterozygous in-frame deletion and ten heterozygous missense mutations affecting recurrent residues in 18 of the 19 individuals screened for SGS; these individuals included one family affected by somatic mosaicism. All mutations were located in a restricted area of exon 1, within the R-SMAD binding domain of SKI. No mutation was found in a cohort of 11 individuals with other marfanoid-craniosynostosis phenotypes. The interaction between SKI and Smad2/3 and Smad 4 regulates TGF-β signaling, and the pattern of anomalies in Ski-deficient mice corresponds to the clinical manifestations of SGS. These findings define SGS as a member of the family of diseases associated with the TGF-β-signaling pathway. Copyright © 2012 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.
Marcelain, Katherine; Armisen, Ricardo; Aguirre, Adam; Ueki, Nobuhide; Toro, Jessica; Colmenares, Clemencia; Hayman, Michael J
Ski is a transcriptional regulator that has been considered an oncoprotein given its ability to induce oncogenic transformation in avian model systems. However, studies in mouse and in some human tumor cells have also indicated a tumor suppressor activity for this protein. We found that Ski-/- mouse embryo fibroblasts exhibit high levels of genome instability, namely aneuploidy, consistent with a tumor suppressor function for Ski. Time-lapse microscopy revealed lagging chromosomes and chromatin/chromosome bridges as the major cause of micronuclei (MN) formation and the subsequent aneuploidy. Although these cells arrested in mitosis after treatment with spindle disrupting drugs and exhibited a delayed metaphase/anaphase transition, spindle assembly checkpoint (SAC) was not sufficient to prevent chromosome missegregation, consistent with a weakened SAC. Our in vivo analysis also showed dynamic metaphase plate rearrangements with switches in polarity in cells arrested in metaphase. Importantly, after ectopic expression of Ski the cells that displayed this metaphase arrest died directly during metaphase or after aberrant cell division, relating SAC activation and mitotic cell death. This increased susceptibility to undergo mitosis-associated cell death reduced the number of MN-containing cells. The presented data support a new role for Ski in the mitotic process and in maintenance of genetic stability, providing insights into the mechanism of tumor suppression mediated by this protein. Copyright © 2011 Wiley Periodicals, Inc.
SKI (the Swedish Nuclear Power Inspectorate) has sent SKB's (the Swedish Nuclear Fuel and Waste Management Co.) RD and D Programme 95 to sixty authorities and organizations for review. 35 reviewing bodies have replied. In various ways, most of the comments are related to the decision-making process, both with regard to site selection and choice of method and only a small number of reviewing bodies have dealt with the more purely technical issues such as the function of the barriers and the safety assessment methodology. SKI's review of the programme is based on the premises of establishing whether and how the programme can fulfill its actual purpose to identify and implement solutions for the final disposal of the spent nuclear fuel from the Swedish nuclear power plants. SKI's statement to the Government includes a 'Summary and Conclusions' of the 'Review Report'. In (the present) 'Review Report' SKI reviews the programme and deals with comments from the other reviewing bodies. Furthermore, SKI has commissioned a separate report with the 'Comments of the Reviewing Bodies'. 32 refs
David R. Mottram
Full Text Available This new edition includes fresh information regarding drugs use and abuse in sport and the updated worldwide anti-doping laws, and changes to the prohibited and therapeutic use exemption lists. The objectives of the book are to review/discuss the latest information on drugs in sport by considering i actions of drugs and hormones, ii medication and nutritional supplements in sport, iii the latest doping control regulations of the WADA, iv the use of banned therapeutic drugs in sport, v an assessment of the prevalence of drug taking in sport. FEATURES A common, uniform strategy and evidence-based approach to organizing and interpreting the literature is used in all chapters. This textbook is composed of twelve parts with sub-sections in all of them. The topics of the parts are: i An introduction to drugs and their use in sport, ii Drug use and abuse in sport, iii Central nervous system stimulants, iv WADA regulations in relation to drugs used in the treatment of respiratory tract disorders, v Androgenic anabolic steroids, vi Peptide and glycoprotein hormones and sport, vii Blood boosting and sport, viii Drug treatment of inflammation in sports injuries, ix Alcohol, anti-anxiety drugs and sport, x Creatine, xi Doping control and sport, xii Prevalence of drug misuse in sport. Each specific chapter has been systematically developed from the data available in prospective, retrospective, case-control, and cross-sectional studies. The tables and figures are numerous, helpful and very useful. AUDIENCE The book provides a very useful resource for students on sports related courses, coaches and trainers, researchers, nutritionists, exercise physiologists, pharmacologists, healthcare professionals in the fields of sports medicine and those involved in the management and administration side of sport. The readers are going to discover that this is an excellent reference book. Extensively revised new edition of this book is also a first-rate resource for
Full Text Available A standing debate in philosophy of sport concerns whether sport can count as art in some sense. But the debate is often conducted at cross purposes. Naysayers insist that no sport is an artform while proponents insist that certain sport performances count as artworks – but these are entirely consistent claims. Both sides make unwarranted assumptions: naysayers are purists about sport and art (no transaesthetic purposes whereas proponents are tokenists about artforms. Naysayers admit that figure skating may count as art yet only in non-competitive contexts. Their burden is thus to explain why a routine (e.g., Torvill and Dean’s ‘Bolero’ may count as art in a showcase but not at the Olympics. The debate is also inevitably framed in terms of whether sport counts as art, neglecting the equally viable question of whether art in some form (e.g., competitive dance may also count as sport. I conclude in favour of an appropriately qualified sport-as-art thesis.
This new edition includes fresh information regarding drugs use and abuse in sport and the updated worldwide anti-doping laws, and changes to the prohibited and therapeutic use exemption lists. The objectives of the book are to review/discuss the latest information on drugs in sport by considering i) actions of drugs and hormones, ii) medication and nutritional supplements in sport, iii) the latest doping control regulations of the WADA, iv) the use of banned therapeutic drugs in sport, v) an...
Full Text Available This work offers a short review of sports marketing and management. It presents different ways of advertising some products either in sports events or throng electronic mediums. In addition, it reviles different aspects of the influence that politics and discrimination has on sport as well as the way of solving eventual arguments of any kind.
... Videos for Educators Search English Español Cold-Weather Sports KidsHealth / For Teens / Cold-Weather Sports What's in this article? What to Do? Classes ... weather. What better time to be outdoors? Winter sports can help you burn calories, increase your cardiovascular ...
The author argues that the fundamental values associated with sports seem to have changed. Accordingly spaces for sports are also undergoing change.The essay gives a number of examples of these new sports spaces. Their common denominator lies in their urban proximity, the combination of previously...
More than half the Dutch population participated in sport on a weekly basis in 2014. Fitness training and running are the most popular sports among adults. Government interventions at the level of neighbourhoods, primary schools, secondary schools and sports clubs are intended to persuade more
Pill, Shane; Hastie, Peter
In order to plan and enact appropriate learning environments in physical education (PE) teachers are increasingly directed to models based practice. The Sport Education model is one of these models for PE curriculum and teaching design that informs the content and pedagogical direction of sport teaching in PE. Despite Sport Education being well…
Myer, Gregory D.; Jayanthi, Neeru; Difiori, John P.; Faigenbaum, Avery D.; Kiefer, Adam W.; Logerstedt, David; Micheli, Lyle J.
Context: There is increased growth in sports participation across the globe. Sports specialization patterns, which include year-round training, participation on multiple teams of the same sport, and focused participation in a single sport at a young age, are at high levels. The need for this type of early specialized training in young athletes is currently under debate. Evidence Acquisition: Nonsystematic review. Study Design: Clinical review. Level of Evidence: Level 4. Conclusion: Sports specialization is defined as year-round training (greater than 8 months per year), choosing a single main sport, and/or quitting all other sports to focus on 1 sport. Specialized training in young athletes has risks of injury and burnout, while the degree of specialization is positively correlated with increased serious overuse injury risk. Risk factors for injury in young athletes who specialize in a single sport include year-round single-sport training, participation in more competition, decreased age-appropriate play, and involvement in individual sports that require the early development of technical skills. Adults involved in instruction of youth sports may also put young athletes at risk for injury by encouraging increased intensity in organized practices and competition rather than self-directed unstructured free play. Strength-of-Recommendation Taxonomy (SORT): C. PMID:26502420
Council of Europe, Strasbourg (France).
The following papers were prepared for a seminar on sport for older people: (1) "Gerontological Aspects of Physical Exercise" (Eino Heikkinen); (2) "Sporting Activities in the Individual Life from the View of Older Persons" (Henning Allmer); (3) "Reasons Why Decision-Makers Should Urge Old People to Practise Physical and Sporting Activities"…
Cunningham, G.; Fairley, S.; Ferkins, L.; Lock, Daniel; Kerwin, S.; Shaw, S.; Wicker, P.
The purpose of this article is to add to the conceptual discussion on eSport, analyze the role of\\ud eSport within sport management, and suggest avenues for future eSport research. The authors\\ud suggest that debates surround the degree to which eSport represents formal sport, and\\ud disagreements likely stem from conceptualizations of sport and context. Irrespective of one’s\\ud notion of eSport as formal sport, the authors suggest the topic has a place in sport management\\ud scholarship and ...
Norberta Elisa Fernandes
Full Text Available The purpose of this study was to examine the relationships between sport commitment and three types of sport consumer behaviors: participation frequency, sporting goods and media consumption. A survey was conducted among sport participants of both individual and team sports, fitness and outdoor activities (n= 900. The survey included questions related to demographic information, measures of sport commitment and sport consumption behavior. The results analyzed trough structural equation modeling showed that the sport commitment influences positively the participation frequency, sporting goods consumption and media consumption. Implications of these results are discussed and suggestions for future research on sport consumers are provided.
...-AA00 Safety Zone; Summer in the City Water Ski Show; Fox River, Green Bay, WI AGENCY: Coast Guard, DHS... River in Green Bay, WI. This safety zone is intended to restrict vessels from a portion of the Fox River... Waterboard Warrior Ski Team will perform two 30-minute shows on the Fox River between the Hwy 141 Bridge and...
... Mt. Rose Ski Tahoe--Atoma Area Environmental Impact Statement AGENCY: Forest Service, USDA. ACTION... the effects of a proposal from Mt. Rose Ski Tahoe (Mt. Rose) to expand its lift and terrain network. The project is located approximately 12 miles west of the intersection of Mt. Rose Highway (Nevada...
Virmavirta, Mikko; Kivekäs, Juha
The special wind compensation system recently adopted by Fédération Internationale de Ski (FIS; International Ski Federation) to consider the effects of changing wind conditions has caused some controversy. Here, the effect of wind on jumping distance in ski jumping was studied by means of computer simulation and compared with the wind compensation factors used by FIS during the World Cup season 2009/2010. The results showed clearly that the effect of increasing head/tail wind on jumping distance is not linear: +17.4 m/-29.1 m, respectively, for a wind speed of 3 m/s. The linear formula used in the trial period of the wind compensation system was found to be appropriate only for a limited range of jumping distances as the gradient of the landing slope slows down the rate of distance change in long jumps.
Chardonnens, Julien; Favre, Julien; Le Callennec, Benoit; Cuendet, Florian; Gremion, Gérald; Aminian, Kamiar
We propose a new method, based on inertial sensors, to automatically measure at high frequency the durations of the main phases of ski jumping (i.e. take-off release, take-off, and early flight). The kinematics of the ski jumping movement were recorded by four inertial sensors, attached to the thigh and shank of junior athletes, for 40 jumps performed during indoor conditions and 36 jumps in field conditions. An algorithm was designed to detect temporal events from the recorded signals and to estimate the duration of each phase. These durations were evaluated against a reference camera-based motion capture system and by trainers conducting video observations. The precision for the take-off release and take-off durations (indoor jumping technique did not influence the error of take-off release and take-off. Therefore, the proposed system can provide valuable information for performance evaluation of ski jumpers during training sessions.
Full Text Available Alpine skiing is characterized by a great number of leg movements with muscle contractions in eccentric regime. The role of these movements is to absorb gravitation and inertial forces, manage skis more precisely and maintain balance. Recent studies have determined the volume, duration and intenisty of eccentric contractions as well as the basic characteristics of movement amplitudes and velocities. Based on the previous findings the experiments involving eccentric training using a bicycle ergometer confirmed a positive impact that this kind of training has on increasing maximum power, strength, endurance, coordination, injury prevention, metabolic work efficiency, more efficient work with longer muscle length and its role in miming skiers' movements. This paper is an review of the studies so far in the field of kinematics, skiing dynamics and the effect of eccentric training on the development of athletes' performances.
Grasaas, Erik; Hegge, Ann Magdalen; Ettema, Gertjan; Sandbakk, Øyvind
We investigated the effects of poling on physiological, kinematic and kinetic responses in the G4 skating technique where the poling movement is synchronized with the leg push-off on one side (strong side) followed by a forward arm swing during the leg push-off on the other side (weak side). G4 skating with (G4-P) and without (G4-NP) poling was compared in 17 elite male cross-country skiers during 4-min submaximal tests on a 2% inclined roller ski treadmill at 10, 15 and 20 km h(-1). G4-P demonstrated less ventilatory stress and higher gross efficiency compared to G4-NP at all velocities, and the blood lactate concentration was lower at the high velocity (all P skating technique. Thus, poling provides possibilities to increase total propulsion, to reduce ski forces and to enhance skiing efficiency.
Hegge, Ann Magdalen; Ettema, Gertjan; de Koning, Jos J; Rognstad, Asgeir Bakken; Hoset, Martin; Sandbakk, Øyvind
This study analyzed the biomechanical and physiological effects of the arm swing in roller ski skating, and compared leg-skating (i.e. ski skating without poles) using a pronounced arm swing (SWING) with leg-skating using locked arms (LOCKED). Sixteen elite male cross-country skiers performed submaximal stages at 10, 15 and 20kmh(-1) on a 2% inclined treadmill in the two techniques. SWING demonstrated higher peak push-off forces and a higher force impulse at all speeds, but a longer cycle length only at the highest speed (all Pskating increases the ski forces and aerobic energy cost at low and moderate speeds, whereas the greater forces at high speed lead to a longer cycle length and smaller anaerobic contribution. Copyright © 2014 Elsevier B.V. All rights reserved.
Full Text Available Sustainability is increasing in importance in relation to the competitiveness of winter tourism, particularly when considering mountain destinations. Exploring in more detail winter tourism related to ski resorts, operators are especially concerned about environmental issues caused by climate change. Therefore, they have gradually become aware of the importance of finding adequate solutions to cope with such issues as well as being able to sensitize tourists. The main goal of this paper is to analyze the different sustainable tools that can be adopted by the ski industry. In this field there appear to be two main approaches. The first line is that of sustainable labels being applied to local ski resorts; whereas the second consists in operators—such as the managers of cable cars—making use of specific labels or management systems that are environmentally oriented.
On December 16, 1993, the Government decided (M93/2525/6), with regard to the 1992 Programme for Research, Development, Demonstration and Other Measures (RD and D Programme 92), compiled by the Swedish Nuclear Fuel and Waste Management Co (SKB) in accordance with Section 12 of the Act on Nuclear Activities, that RD and D Programme 92 should be supplemented by SKB in the manner specified in the decision. On August 19, 1992, SKB submitted the requested supplement to the Swedish Nuclear Power Inspectorate (SKI). SKI has examined the supplement and has requested and obtained comments from a large number of reviewing bodies. SKI hereby submits the documents on the matter along with its own review report. The review report contains an evaluation of SKB's supplement in relation to the government decision and certain recommendations for the structuring of the licensing procedure for planned facilities. These recommendations have taken into account the statements of the reviewing bodies
Sandbakk, Øyvind; Ettema, Gertjan; Holmberg, Hans-Christer
Poling is considered to make a significant contribution to cross-country skiing with the skating technique. To better understand this contribution, the current investigation compared roller ski skating on a treadmill with the so-called G3 skating technique with (G3-P) and without poling (G3-NP). Seven male elite skiers performed 5-min submaximal tests at 8, 12, and 15 km h(-1), as well as an incremental test to exhaustion with both techniques on a 5 % incline. Ventilatory variables were assessed by open-circuit indirect calorimetry and three-dimensional kinematics analyzed using the Qualisys Pro Reflex system. G3-P was associated with approximately 15 % higher peak velocity and 10 % higher peak oxygen uptake than G3-NP in the incremental test (both P skating, specifically by enhancing peak oxygen uptake, skiing efficiency and associated biomechanical variables.
Andersson, E; Björklund, G; Holmberg, H-C
To improve current understanding of energy contributions and determinants of sprint-skiing performance, 11 well-trained male cross-country skiers were tested in the laboratory for VO2max , submaximal gross efficiency (GE), maximal roller skiing velocity, and sprint time-trial (STT) performance...... during the STT was predicted from the submaximal relationships for GE against velocity and incline, allowing computation of metabolic rate and O2 deficit. The skiers completed the STT in 232 ± 10 s (distributed as 55 ± 3% DP and 45 ± 3% DS) with a mean power output of 324 ± 26 W. The anaerobic energy......-skiing has demonstrated an anaerobic energy contribution of 18%, with GE being the strongest predictor of performance....
A.S. Teletov; V.I. Karpets
The aim of the article. The aim of the article is to clarify the concept of «sport tourism marketing», to examine the state of its objects and to determine prospects for development of sport tourism in Ukraine. The paper singles out the role of sport in life; compares different types of cities in terms of provision the infrastructure for tourism development in the field of sports. Authors show the example of the campaign. The results of the analysis. The article deals with sport tourism as...
Chardonnens, Julien; Favre, Julien; Cuendet, Florian; Gremion, Gérald; Aminian, Kamiar
Three-dimensional analysis of the entire sequence in ski jumping is recommended when studying the kinematics or evaluating performance. Camera-based systems which allow three-dimensional kinematics measurement are complex to set-up and require extensive post-processing, usually limiting ski jumping analyses to small numbers of jumps. In this study, a simple method using a wearable inertial sensors-based system is described to measure the orientation of the lower-body segments (sacrum, thighs, shanks) and skis during the entire jump sequence. This new method combines the fusion of inertial signals and biomechanical constraints of ski jumping. Its performance was evaluated in terms of validity and sensitivity to different performances based on 22 athletes monitored during daily training. The validity of the method was assessed by comparing the inclination of the ski and the slope at landing point and reported an error of -0.2±4.8°. The validity was also assessed by comparison of characteristic angles obtained with the proposed system and reference values in the literature; the differences were smaller than 6° for 75% of the angles and smaller than 15° for 90% of the angles. The sensitivity to different performances was evaluated by comparing the angles between two groups of athletes with different jump lengths and by assessing the association between angles and jump lengths. The differences of technique observed between athletes and the associations with jumps length agreed with the literature. In conclusion, these results suggest that this system is a promising tool for a generalization of three-dimensional kinematics analysis in ski jumping. Copyright © 2012 Elsevier Ltd. All rights reserved.
Danilo Aćimović; Omer Špirtović
Discussion about sport marketing implies its theoretical definition and generalization, and then its actual definition in sport environment. Sport marketing, belongs to the newer type of the marketing. It appeared in time of increasing activity and significance of sport in the world. Huge human potential, with which sport as an activity disposes, implied the need to organize more properly and use it purposefully. “Sport marketing belongs to business function of sport organization and represen...
Dain, Stephen J
Eye injuries sustained during sport comprise up to 20 per cent of all injuries to the eye serious enough for medical attention to be sought. The prevalence of eye injuries in sport is not easily assessed due to lack of authoritative participation rates, so most studies report total numbers in a time period. The evidence on the proportion of all ocular injuries that are from sport is reviewed. The relative frequencies in different sports are compared in a qualitative manner and the sports with greater numbers of ocular injuries are detailed. In common with occupational injuries to the eye, most sports eye injuries are considered preventable. The hierarchy of action for occupational risk is detailed and adapted to use in a sports scenario. All the available international, regional and national standards on sports eye protection are detailed and their provisions compared. The major function of the standards is to provide adequate protection against the hazard of the sport concerned. These are detailed and compared as a function of energy transfer. Eye protection must not introduce additional or secondary hazards (for instance, fracturing into sharp fragments on impact) and not introduce features that would deter the wearing of eye protection (for instance, restricting field of view to impede playing the sport). The provisions of the standards intended to limit secondary hazards are detailed and compared. The need for future work in standards writing and the activities of the International Standardization Organization in sports eye protection are detailed. © 2016 Optometry Australia.
Møller, Rasmus Bysted; Møller, Verner
The relationship between sport and technology is close and can be both fruitful and destructive. Technology has a constitutive function in sport as it makes the activity possible and it can enhance performance as well as the sporting experience. The use of football boots is clearly more comfortable...... and effective than playing in bare feet in a game of football. However, sport challenges its athletes by demanding the employment of less efficient means rather than more efficient means in pursuit of sport specific goals. Therefore technology can potentially subtract from the sporting experience and even...... threaten the internal logic of sport. If as an example very efficient hail cartridges were allowed for use in double trap shooting it would reduce the skills required to excel at that discipline reducing its value for participants and spectators alike. The use of forbidden performance enhancing substances...
In SKI's opinion, the Swedish Nuclear Fuel and Waste Management Co (SKB) has presented a research and development program which fulfills the basic requirements stipulated in the Act on Nuclear Activities. On the whole, the program is appropriate with regard to the development and evaluation of a method for the final disposal of spent nuclear fuel and nuclear waste in the Swedish bedrock. The quality of the supporting research program is high. However, in SKI's view, the General Siting Study should be supplemented with regard to certain points and the siting factors should be further specified
Hanzer, F.; Marke, T.; Steiger, R.; Strasser, U.
Tourism and particularly winter tourism is a key factor for the Austrian economy. Judging from currently available climate simulations, the Austrian Alps show a particularly high vulnerability to climatic changes. To reduce the exposure of ski areas towards changes in natural snow conditions as well as to generally enhance snow conditions at skiing sites, technical snowmaking is widely utilized across Austrian ski areas. While such measures result in better snow conditions at the skiing sites and are important for the local skiing industry, its economic efficiency has also to be taken into account. The current work emerges from the project CC-Snow II, where improved future climate scenario simulations are used to determine future natural and artificial snow conditions and their effects on tourism and economy in the Austrian Alps. In a first step, a simple technical snowmaking approach is incorporated into the process based snow model AMUNDSEN, which operates at a spatial resolution of 10-50 m and a temporal resolution of 1-3 hours. Locations of skiing slopes within a ski area in Styria, Austria, were digitized and imported into the model environment. During a predefined time frame in the beginning of the ski season, the model produces a maximum possible amount of technical snow and distributes the associated snow on the slopes, whereas afterwards, until to the end of the ski season, the model tries to maintain a certain snow depth threshold value on the slopes. Due to only few required input parameters, this approach is easily transferable to other ski areas. In our poster contribution, we present first results of this snowmaking approach and give an overview of the data and methodology applied. In a further step in CC-Snow, this simple bulk approach will be extended to consider actual snow cannon locations and technical specifications, which will allow a more detailed description of technical snow production as well as cannon-based recordings of water and energy
Full Text Available For the determination of ground reaction forces in alpine skiing, pressure insole (PI systems and portable force plate (FP systems are well known and widely used in previous studies. The purposes of this study were 1 to provide reference data for the vertical component of the ground reaction forces (vGRF during alpine skiing measured by the PI and FP systems, and 2 to analyze whether the differences in the vGRF measured by the PI and the FP depend on a skier's level, skiing mode and pitch. Ten expert and ten intermediate level skiers performed 10 double turns with the skiing technique "Carving in Short Radii" as High Dynamic Skiing mode and "Parallel Ski Steering in Long Radii" as Low Dynamic Skiing mode on both the steep (23 ° and the flat (15 ° slope twice. All subjects skied with both the PI and the FP system simultaneously. During the outside phase, the mean vGRF and the maximum vGRF determined by the FP are greater than the PI (p < 0.01. Additionally during the inside phase, the mean vGRF determined by the FP were greater than the PI (p < 0.01. During the edge changing phases, the mean vGRF determined by the FP were greater than the PI (p < 0.01. However, the minimum vGRF during the edge changing phases determined by the FP were smaller than the PI (p < 0.01 in the High-Steep skiing modes of Experts and Intermediates (p < 0.001. We have found that generally, the PI system underestimates the total vGRF compared to the FP system. However, this difference depends not only the phase in the turn (inside, outside, edge changing, but also is affected by the skier's level, the skiing mode performed and pitch.
Clarys, J P; Cabri, J
Within electromyography (EMG), a particular specialty has been developed wherein the aim is to use EMG for the study of muscular function and co-ordination. This area of research is usually called kinesiological EMG. The general aims of kinesiological EMG are to analyse the function and co-ordination of muscles in different movements and postures, in healthy subjects as well as in the disabled, in skilled actions as well as during training, in humans as well as in animals, under laboratory conditions as well as during daily or vocational activities. This is often done by a combination of electromyographical and kinesiological or biomechanical measurement techniques. Because there are over 400 skeletal muscles in the human body and both irregular and complex involvement of the muscles may occur in neuromuscular diseases and in voluntary occupational or sports movements, it is impossible to sample all of the muscles of the entire body during the performance of complex motor skills. In addition, the measurement of kinesiological EMG in sport and specific field circumstances, such as the track and/or soccer field, the alpine ski slope, the swimming pool and the ice rink, demands a specific technological and methodological approach, adaptable to both the field and the sport circumstances. Sport movement techniques and skills, training approaches and methods, ergonomic verification of the human-machine interaction have, amongst others, a highly specialized muscular activity in common. The knowledge of such muscular action in all its aspects, its evaluation and its feedback should allow for the optimization of movement, of sports materials, of training possibilities and, in the end, of sports performance. Drawing conclusions from a review of the EMG research of 32 sports, covering over 100 different complex skills, including methodological approaches, is an impossible task. We have attempted to set standards concerning the EMG methodology at the beginning of this review
Thomson, Cynthia J.; Rajala, Amelia K.; Carlson, Scott R.; Rupert, Jim L.
Sensation seeking is a personality trait that has been associated with disinhibited behaviours including substance use and gambling, but also with high-risk sport practices including skydiving, paragliding, and downhill skiing. Twin studies have shown that sensation seeking is moderately heritable, and candidate genes encoding components involved in dopaminergic transmission have been investigated as contributing to this type of behaviour. To determine whether variants in the regulatory regio...
Full Text Available In the sport management coordination represents the basic deposit of management, and terms through numerous activities. Brother-in-law activity in sport has the specific management so speak about the management of sport event, management of sports facilities, management of management to the human activities, financial management in sport etc. The sportively management has presumed the specific management related to sports activities whose basic task of coordinations of sports activities. Management of sport organisations have been confided sport managers of special profile which differs towards the type of sport, rank of contest etc. The sport managers could utter survived the statement that in sport have not been educated special diameters manager, besides sport coaches. Specifically, in the role of manager in sport prevails almost all diameters of professional in professional or the volunteer relationship.
Fridman, Liraz; Fraser-Thomas, Jessica L; McFaull, Steven R; Macpherson, Alison K
Although injuries related to sports and recreation represent a significant burden to children and youth, few studies have examined the descriptive epidemiology of sports-related injury since 2005, and some sports such as ringette have not been evaluated to date. The primary purpose of this study was to provide the descriptive epidemiology of sports-related injuries treated in emergency departments for children and youth aged 5 - 19. A retrospective data analysis was performed using data from the Canadian Hospitals Injury Reporting and Prevention Program [CHIRPP] from fiscal years (April - March) 2007/08 to 2009/10. CHIRPP is a computerized information system designed by the Public Health Agency of Canada that collects information about injuries to people evaluated in emergency departments across 11 pediatric hospitals and 5 general hospitals in Canada. Thirteen sports or activities were analyzed (baseball, basketball, cycling, football, ice hockey, lacrosse, ringette, rugby, skiing, sledding, snowboarding, soccer, and volleyball). Descriptive statistics, including frequency by sport, age and sex, as well as the percent of concussions within each sport were calculated. Out of a total of 56, 691 reported sports and recreational injuries, soccer accounted for the largest proportion of injuries with 11,941 reported cases over the 3 year time period. Of these, approximately 30% were fractures. The 10 - 14 year age group reported the greatest proportion of injuries in 10 out of the 13 sports analyzed. In addition, males reported a greater number of overall injuries than females in 11 out of the 13 sports analyzed. The largest percentage of concussions was reported in ringette; these injuries accounted for 17.1% of overall injuries within this sport. Injury prevention programs in Canada should focus on improving evidence-based programs to reduce the burden of injuries in all sports.
Yang, Li; Weng, Wei; Sun, Zhi-Xin; Fu, Xian-Jie; Ma, Jun; Zhuang, Wen-Fang
Previous studies have identified sphingosine kinase 1 (SphK1) as a potential drug target for treatment of acute myeloid leukemia (AML). In the current study, we investigated the potential anti-leukemic activity of a novel and specific SphK1 inhibitor, SKI-II. We demonstrated that SKI-II inhibited growth and survival of human AML cell lines (HL-60 and U937 cells). SKI-II was more efficient than two known SphK1 inhibitors SK1-I and FTY720 in inhibiting AML cells. Meanwhile, it induced dramatic apoptosis in above AML cells, and the cytotoxicity by SKI-II was almost reversed by the general caspase inhibitor z-VAD-fmk. SKI-II treatment inhibited SphK1 activation, and concomitantly increased level of sphingosine-1-phosphate (S1P) precursor ceramide in AML cells. Conversely, exogenously-added S1P protected against SKI-II-induced cytotoxicity, while cell permeable short-chain ceramide (C6) aggravated SKI-II's lethality against AML cells. Notably, SKI-II induced potent apoptotic death in primary human AML cells, but was generally safe to the human peripheral blood mononuclear cells (PBMCs) isolated from healthy donors. In vivo, SKI-II administration suppressed growth of U937 leukemic xenograft tumors in severe combined immunodeficient (SCID) mice. These results suggest that SKI-II might be further investigated as a promising anti-AML agent. - Highlights: • SKI-II inhibits proliferation and survival of primary and transformed AML cells. • SKI-II induces apoptotic death of AML cells, but is safe to normal PBMCs. • SKI-II is more efficient than two known SphK1 inhibitors in inhibiting AML cells. • SKI-II inhibits SphK1 activity, while increasing ceramide production in AML cells. • SKI-II dose-dependently inhibits U937 xenograft growth in SCID mice
Yang, Li; Weng, Wei; Sun, Zhi-Xin; Fu, Xian-Jie; Ma, Jun, E-mail: email@example.com; Zhuang, Wen-Fang, E-mail: firstname.lastname@example.org
Previous studies have identified sphingosine kinase 1 (SphK1) as a potential drug target for treatment of acute myeloid leukemia (AML). In the current study, we investigated the potential anti-leukemic activity of a novel and specific SphK1 inhibitor, SKI-II. We demonstrated that SKI-II inhibited growth and survival of human AML cell lines (HL-60 and U937 cells). SKI-II was more efficient than two known SphK1 inhibitors SK1-I and FTY720 in inhibiting AML cells. Meanwhile, it induced dramatic apoptosis in above AML cells, and the cytotoxicity by SKI-II was almost reversed by the general caspase inhibitor z-VAD-fmk. SKI-II treatment inhibited SphK1 activation, and concomitantly increased level of sphingosine-1-phosphate (S1P) precursor ceramide in AML cells. Conversely, exogenously-added S1P protected against SKI-II-induced cytotoxicity, while cell permeable short-chain ceramide (C6) aggravated SKI-II's lethality against AML cells. Notably, SKI-II induced potent apoptotic death in primary human AML cells, but was generally safe to the human peripheral blood mononuclear cells (PBMCs) isolated from healthy donors. In vivo, SKI-II administration suppressed growth of U937 leukemic xenograft tumors in severe combined immunodeficient (SCID) mice. These results suggest that SKI-II might be further investigated as a promising anti-AML agent. - Highlights: • SKI-II inhibits proliferation and survival of primary and transformed AML cells. • SKI-II induces apoptotic death of AML cells, but is safe to normal PBMCs. • SKI-II is more efficient than two known SphK1 inhibitors in inhibiting AML cells. • SKI-II inhibits SphK1 activity, while increasing ceramide production in AML cells. • SKI-II dose-dependently inhibits U937 xenograft growth in SCID mice.
Peschek, Katelyn; Pritchett, Robert; Bergman, Ethan; Pritchett, Kelly
Dietary flavanols have been associated with reduced oxidative stress, however their efficacy in promoting recovery after exercise induced muscle damage is unclear. This study examined the effectiveness of acute consumption of cocoa-flavanols on indices of muscle recovery including: subsequent exercise performance, creatine kinase, muscle tenderness, force, and self-perceived muscle soreness. Eight endurance-trained athletes (VO2max 64.4 ± 7.6 mL/kg/min) completed a downhill running protocol to induce muscle soreness, and 48-h later completed a 5-K (kilometer) time trial. Muscle recovery measurements were taken at PRE, 24 h-POST, 48 h-POST, and POST-5K. Participants consumed 1.0 g of carbohydrate per kilogram of body weight of a randomly assigned beverage (CHOC: 0 mg flavanols vs. CocoaCHOC: 350 mg flavanols per serving) immediately after the downhill run and again 2 h later. The same protocol was repeated three weeks later with the other beverage. An ANOVA revealed no significant difference (p = 0.97) between trials for 5 K completion time (CHOC 1198.3 ± 160.6 s, CocoaCHOC 1195.5 ± 148.8 s). No significant difference was found for creatine kinase (CK) levels (p = 0.31), or muscle soreness (p = 0.21) between groups over time. These findings suggest that the acute addition of cocoa flavanols to low-fat chocolate milk offer no additional recovery benefits. PMID:24362706
Full Text Available Dietary flavanols have been associated with reduced oxidative stress, however their efficacy in promoting recovery after exercise induced muscle damage is unclear. This study examined the effectiveness of acute consumption of cocoa-flavanols on indices of muscle recovery including: subsequent exercise performance, creatine kinase, muscle tenderness, force, and self-perceived muscle soreness. Eight endurance-trained athletes (VO2max 64.4 ± 7.6 mL/kg/min completed a downhill running protocol to induce muscle soreness, and 48-h later completed a 5-K (kilometer time trial. Muscle recovery measurements were taken at PRE, 24 h-POST, 48 h-POST, and POST-5K. Participants consumed 1.0 g of carbohydrate per kilogram of body weight of a randomly assigned beverage (CHOC: 0 mg flavanols vs. CocoaCHOC: 350 mg flavanols per serving immediately after the downhill run and again 2 h later. The same protocol was repeated three weeks later with the other beverage. An ANOVA revealed no significant difference (p = 0.97 between trials for 5 K completion time (CHOC 1198.3 ± 160.6 s, CocoaCHOC 1195.5 ± 148.8 s. No significant difference was found for creatine kinase (CK levels (p = 0.31, or muscle soreness (p = 0.21 between groups over time. These findings suggest that the acute addition of cocoa flavanols to low-fat chocolate milk offer no additional recovery benefits.
Farrokhi, Shawn; Voycheck, Carrie A; Gustafson, Jonathan A; Fitzgerald, G Kelley; Tashman, Scott
The objective of this exploratory study was to evaluate tibiofemoral joint contact point excursions and velocities during downhill gait and assess the relationship between tibiofemoral joint contact mechanics with frontal-plane knee joint motion and lower extremity muscle weakness in patients with knee osteoarthritis (OA). Dynamic stereo X-ray was used to quantify tibiofemoral joint contact mechanics and frontal-plane motion during the loading response phase of downhill gait in 11 patients with knee OA and 11 control volunteers. Quantitative testing of the quadriceps and the hip abductor muscles was also performed. Patients with knee OA demonstrated larger medial/lateral joint contact point excursions (p knee OA compared to their control counterparts (p = 0.02). Additionally, patients with knee OA demonstrated significantly increased frontal-plane varus motion excursions (p knee OA were linearly associated with greater frontal-plane varus motion excursions (p knee OA may be related to compromised frontal-plane joint stability but not with deficits in muscle strength.
Natural and artificial lighting is an important factor of comfort, pleasure and safety in sporting facilities and influences the construction costs but also the frequenting of installations. The duration of use of installations and the profitability of investments are directly linked with the prolongation of visiting hours for competition, training and leisure purposes. This book presents, first, the common recommendations and principles for the lighting of sporting facilities in general. The particular recommendations relative to some specific activities are considered in a second part (golf, ski, bowls, pelota, skate-board, hippodromes etc..). (J.S.)
Full Text Available The article deals with the development of the youth athletic and sports movement in the Penza region in the first half of 1941 – before the Great Patriotic War. The activities of local Soviet-party and public organizations for the health improvement and military sport training of the population, especially the young: mass ski trips and crosses, gymnastics competitions, athletic crosses (for the Day of the Bolshevik Press, of Komsomol-trade union, for the prize of the "Young Leninist" newspaper, etc..
Mourot, Laurent; Fabre, Nicolas; Andersson, Erik; Willis, Sarah J; Hébert-Losier, Kim; Holmberg, Hans-Christer
The aim of this study was to assess potential changes in the performance and cardiorespiratory responses of elite cross-country skiers following transition from the classic (CL) to the skating (SK) technique during a simulated skiathlon. Eight elite male skiers performed two 6 km (2 × 3 km) roller-skiing time trials on a treadmill at racing speed: one starting with the classic and switching to the skating technique (CL1-SK2) and another employing the skating technique throughout (SK1-SK2), with continuous monitoring of gas exchanges, heart rates, and kinematics (video). The overall performance times in the CL1-SK2 (21:12 ± 1:24) and SK1-SK2 (20:48 ± 2:00) trials were similar, and during the second section of each performance times and overall cardiopulmonary responses were also comparable. However, in comparison with SK1-SK2, the CL1-SK2 trial involved significantly higher increases in minute ventilation (V̇E, 89.8 ± 26.8 vs. 106.8 ± 17.6 L·min(-1)) and oxygen uptake (V̇O2; 3.1 ± 0.8 vs 3.5 ± 0.5 L·min(-1)) 2 min after the transition as well as longer time constants for V̇E, V̇O2, and heart rate during the first 3 min after the transition. This higher cardiopulmonary exertion was associated with ∼3% faster cycle rates. In conclusion, overall performance during the 2 time trials did not differ. The similar performance times during the second sections were achieved with comparable mean cardiopulmonary responses. However, the observation that during the initial 3-min post-transition following classic skiing cardiopulmonary responses and cycle rates were slightly higher supports the conclusion that an initial section of classic skiing exerts an impact on performance during a subsequent section of skate skiing.
Lee, Donghun; Schoenstedt, Linda J.
With recognition of the need for studying eSports in this interactive digital communication era, this study explored 14 motivational factors affecting the time spent on eSports gaming. Using a sample of 515 college students and athletic event attendees, we further compared eSports game patterns to their non-eSport or traditional sport involvements…
Addresses junior sport and sport culture in New Zealand, recommending that it receive serious consideration for its crucial role in the future of New Zealand's sport culture. The paper presents three goals for junior sport programs (educative, public health, and elite development), describes characteristics of junior sport (e.g., youth want to…
Williams, Vernon B
Sports neurology is an emerging area of subspecialty. Neurologists and non-neurologists evaluating and managing individuals participating in sports will encounter emergencies that directly or indirectly involve the nervous system. Since the primary specialty of sports medicine physicians and other practitioners involved in the delivery of medical care to athletes in emergency situations varies significantly, experience in recognition and management of neurologic emergencies in sports will vary as well. This article provides a review of information and elements essential to neurologic emergencies in sports for the practicing neurologist, although content may be of benefit to readers of varying background and expertise. Both common neurologic emergencies and less common but noteworthy neurologic emergencies are reviewed in this article. Issues that are fairly unique to sports participation are highlighted in this review. General concepts and principles related to treatment of neurologic emergencies that are often encountered unrelated to sports (eg, recognition and treatment of status epilepticus, increased intracranial pressure) are discussed but are not the focus of this article. Neurologic emergencies can involve any region of the nervous system (eg, brain, spine/spinal cord, peripheral nerves, muscles). In addition to neurologic emergencies that represent direct sports-related neurologic complications, indirect (systemic and generalized) sports-related emergencies with significant neurologic consequences can occur and are also discussed in this article. Neurologists and others involved in the care of athletes should consider neurologic emergencies in sports when planning and providing medical care.
Pidwirny, M. J.; Goode, J. D.; Pedersen, S.
The winter of 2015 will go down as "the year without a ski season" for many ski resorts located close to the west coast of Canada and the USA. During this winter season, a large area of the eastern North Pacific Ocean had extremely high sea surface temperatures. These high sea surface temperatures influenced weather patterns on the west coast of North America producing very mild temperatures inland. Further, in alpine environments precipitation that normally arrives in the form of snow instead fell as rain. This research examines the climate characteristics of the winter of 2015 in greater detail for three ski resorts in British Columbia, Canada: Mount Washington, Cypress Mountain and Hemlock Valley. For these resorts, historical (1901 to 2013) and IPCC AR5 climate model forecasted climate data (RCP8.5 for 2025, 2055, and 2085) was generated for the variable winter degree days climate database ClimateBC. A value for winter degree days climate data at nearby meteorological stations for comparative analysis. For all three resorts, the winter of 2015 proved to be warmer than any individual year in the period 1901 to 2013. Interpolations involving the multi-model ensemble forecast means suggest that the climate associated with winter of 2015 will become the average normal for these resorts in only 35 to 45 years under the RCP8.5 emission scenario.
DURBĂCEA - BOLOVAN MARIAN
Full Text Available Sports and economy have discovered each other, hoping to serve common interests. In view of transferring in a more efficient way the information about their products or services to consumers, the business operator finances sports activities for advertising purposes. A company involved in sports sponsorship can instantly transmit the message about its products to millions of potential buyers, thus increasing the market share and hence the profit that it generates. By sponsoring sport it is meant any agreement / convention, under which one party the sponsor makes available to the beneficiary the material resources, financial and / or other benefits in exchange for its association with a sport or sportsman and especially the promise to use this association with sport or sportsman for the purpose of advertising, especially TV advertising. The growing use of athletes as spokespersons for a product is largely due to the ability of athletes to attract public attention and the credibility they enjoy.
Jéssica Natuline Ianof
Full Text Available ABSTRACT Traumatic brain injury (TBI is a major cause of lifelong disability and death worldwide. Sport-related traumatic brain injury is an important public health concern. The purpose of this review was to highlight the importance of sport-related concussions. Concussion refers to a transient alteration in consciousness induced by external biomechanical forces transmitted directly or indirectly to the brain. It is a common, although most likely underreported, condition. Contact sports such as American football, rugby, soccer, boxing, basketball and hockey are associated with a relatively high prevalence of concussion. Various factors may be associated with a greater risk of sport-related concussion, such as age, sex, sport played, level of sport played and equipment used. Physical complaints (headache, fatigue, dizziness, behavioral changes (depression, anxiety, irritability and cognitive impairment are very common after a concussion. The risk of premature return to activities includes the prolongation of post-concussive symptoms and increased risk of concussion recurrence.
Sports management and its development is closely linked to the development of modern society and modern rationality. This article applies sociological theories and practical management philosophy to shed light on how sports management and its rationality in Denmark (Europe) and the United States...... have changed and undergone different phases for more than a century, and to show that, in late modernity, they are entering a new phase in which they seem to be more reflexive and communicative. This trend is evident in American sports management and will also soon be reflected in Danish sports...... management. My analysis of this development will also be based on a specific case study from the American world of sports, namely the story of Oakland Athletics baseball club’s reorganisation in the 1990s, because it both provides a rare insight into a modern sports organisation and demonstrates...
Full Text Available We can say that sports are continuously evolving. To improve the quality of this work, changes are being made in all of these segments: development and selection of athletes, the improvement of technology for preparation and performance tactics, training methods for relaxation. On the other hand these are followed by rule changes, modern sports facilities, as well as legal regulations. One direction in the improvement of sports results is an attempt at rational spending of existing resources for athletes, regardless of whether in team or individual sports. Nanotechnology is also contributioning toward this direction. This paper points out the appearance of nanotechnology, its essence, i.e., the way it may effect the development of sports. Of course, it also points to the potential risk of applying nanotechnology to sports.
Virmavirta, Mikko; Isolehto, Juha; Komi, Paavo; Schwameder, Hermann; Pigozzi, Fabio; Massazza, Giuseppe
The take-off phase (approximately 6m) of the jumps of all athletes participating in the individual HS-106m hill ski jumping competition at the Torino Olympics was filmed with two high-speed cameras. The high altitude of the Pragelato ski jumping venue (1600m) and slight tail wind in the final jumping round were expected to affect the results of this competition. The most significant correlation with the length of the jump was found in the in-run velocity (r=0.628, pski jumping, and suggests that good jumpers simply had smaller friction between their skis and the in-run tracks and/or the aerodynamic quality of their in-run position was better. Angular velocity of the hip joint of the best jumpers was also correlated with jumping distance (r=0.651, pjumped approximately the same distance. This certainly improves the interests in ski jumping among athletes and spectators. The comparison between the take-off techniques of the best jumpers showed that even though the more marked upper body movement creates higher air resistance, it does not necessarily result in shorter jumping distance if the exposure time to high air resistance is not too long. A comparison between the first and second round jumps of the same jumpers showed that the final results in this competition were at least partly affected by the wind conditions.
Virmavirta, M; Perttunen, J; Komi, P V
Different profiles of ski jumping hills have been assumed to make the initiation of take-off difficult especially when moving from one hill to another. Neuromuscular adaptation of ski jumpers to the different jumping hills was examined by measuring muscle activation and plantar pressure of the primary take-off muscles on three different sized hills. Two young ski jumpers volunteered as subjects and they performed several trials from each hill (K-35 m, K-65 m and K-90 m) with the same electromyographic (EMG) electrode and insole pressure transducer set-up. The results showed that the differences in plantar pressure and EMGs between the jumping hills were smaller than expected for both jumpers. The small changes in EMG amplitudes between the hills support the assumption that the take-off was performed with the same intensity on different jumping hills and the timing of the gluteus EMG demonstrates well the similarity of the muscle activation on different hills. On the basis of the results obtained it seems that ski jumping training on small hills does not disturb the movement patterns for bigger hills and can also be helpful for special take-off training with low speed.
Little, Christopher M.; Needham, Mark D.
Many alpine ski areas have recently adopted voluntary environmental programs (VEPs) such as using recycling, renewable energy, and biofuels to help reduce their environmental impacts. Studies have addressed the performance of these VEPs in mitigating environmental impacts of this industry, but little is known about visitor awareness and perceptions of these programs. This article addresses this knowledge gap by exploring skier and snowboarder knowledge of VEPs at a ski area and the influence of these programs on their motivations to visit this area currently and behavioral intentions to visit again in the future. Data were obtained from an onsite survey at the Mt. Bachelor ski area in Oregon, USA ( n = 429, 89.7% response rate). Few skiers and snowboarders were knowledgeable of VEPs at this area and fewer than 20% were motivated to visit on their current trip because of these programs. Other attributes such as scenery, snow conditions, and access were more important for influencing visitation. Up to 38% of skiers and snowboarders, however, intend to visit this ski area more often if it adopts and promotes more VEPs. Managers can use these results to inform communication and marketing of their environmental programs and performance to visitors. Additional implications for management and future research are discussed.
Varedi, Amir; Secrest, Aaron M; Harding, Garrett; Maness, Lori; Branson, Donna; Smith, Kristi; Hull, Christopher M
Outdoor recreation can lead to substantial sun exposure. Employees of outdoor recreation establishments with extended time outdoors have amplified cumulative exposure to ultraviolet (UV) radiation and an increased risk of skin cancer. The "Sun Safe on the Slopes" program was created by Huntsman Cancer Institute at the University of Utah and the Utah Cancer Action Network to address increased UV exposure and skin cancer risk with free skin cancer screenings, outreach, and prevention education to local ski resorts. Herein, we describe the processes and barriers to implementation of a ski resort skin screening and education program and our 5-year report of the experience and screening data. Nine free skin cancer screenings were held at Utah ski resorts between 2011 and 2016, resulting in the presumptive diagnosis of 38 skin cancers (9.6%) in 394 participants. Behavioral data collected from participants indicates suboptimal sun safety practices, including underuse of sunscreen and protective clothing. Ski resort employees who experience sun exposure during peak hours at high altitudes and UV reflection from the snow are at an increased risk of skin cancer. These data indicate a need for emphasis on sun safety education and screening and can serve as a model for future endeavors.
Teryl G. Grubb; David K. Delaney; William W. Bowerman
Implementing further research was beyond the scope of the U.S. Forest Service's 2004 Final Environmental Impact Statement (FEIS) and 2005 Wasatch Powderbird Guides (WPG) Special Use Permit Renewal process for heli-skiing in the Tri-Canyon Area in the Wasatch Mountains, just east of Salt Lake City, Utah. However, in their Record of Decision the Wasaatch-Cache (WCNF...
Nilsson, Niels Chr.; Serafin, Stefania; Nordahl, Rolf
In this paper we present two comparisons of two novel physical interface for interacting with a virtual environment in the form of a skiing game. The interfaces were compared through two separate within-subjects studies. In the first study we compared a wobble board augmented with a low-cost 3D a...
Full Text Available The environmental impacts in Serbian ski resorts (Kopaonik, Zlatibor, Stara planina, Divčibare are very strong, leading to degradation of unique mountain landscape, and functionality losses. Processes of urbanization, construction or improvement works, cause hard degradation of topsoil and native vegetation. The logging, large excavation activities, erosion, noise and water pollution constantly impact the habitats of all animal and plant species residing in small areas. The process leads to severe fragmentation of the remaining old-growth forests, endangering future subsistence. Consequences of mismanagement in ski areas are noticeable in downstream sections of river beds, causing floods and bed-load deposition, with high concentration of pollutants, in reservoirs for water supply. Legal nature-protection standards are weakly implemented in regional ski areas. Effective protection of landscape in Serbian ski-areas is based on careful considerations of impact assessment at all levels of planning (spatial and urban planning and designing activities, which enables application of restoration concept, in accordance with general goals of environmental protection (preserving biodiversity, CO2 sequestration, attenuation of effects of global climate changes.
Full Text Available Lately, Internet constitutes a major tool for transactions in every aspect and supports innovative marketing policies. Broadband Internet has become “the key to success” for businesses, as it offers various advantages and benefits through Internet marketing (e-marketing policies. In Greece, mountainous areas are usually covered with snow during winter months; so, skiing centers have become an important asset for winter tourism. The Internet evolution and the development of network infrastructure enhance marketing policies for winter tourism activities. This paper studies the use of marketing policies in Greek skiing centers through the Internet, such as promotional activities, website interactivity, accommodation & entertainment information, online weather forecast, guest book, etc Therefore, the paper aims to optimize and evaluate skiing centers in Greece, qualitatively and quantitatively according to e-marketing policies used as criteria, based on the multicriteria method of PROMETHEE II and further to classify them in groups. Finally we identify and describe the optimum group of skiing centers to be used as a model with enhanced customer communication services.
Stratil, Antonín; Knorr, C.; Knoll, Aleš; Kubíčková, S.; Musilová, P.; Van Poucke, M.; Rubeš, J.; Brenig, B.; Peelman, L. J.
Roč. 36, - (2005), s. 272-273 ISSN 0268-9146 R&D Projects: GA ČR GA523/03/0858 Institutional research plan: CEZ:AV0Z50450515 Keywords : SKI gene * GABRD gene Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.437, year: 2005
Gettman, Larry R.; Huckel, Jack R.
The purpose of this study was to relate leg strength and power to alpine skiing success as measured by FIS points. Isometric leg strength was represented by the knee extension test described by Clarke. Leg power was measured by the vertical jump test and the Margaria-Kalamen stair run. Results in the strength and power tests were correlated with…
Traks, Kristina, 1976-
Ilmunud ka: Delovõje Vedomosti 22. okt. lk. 7. Rocca al Mare Suurhalli aktsionärid otsustasid müüa suurhalli hotelliärimehe Toonart Rääski ja meelelahutusettevõtja Aivar Riisaluga seotud firmale Neckman Group. Diagramm: Lemminkäinen Eesti, Neckman Groupi, Eesti riigi ja Tallinna linna osalused Rocca al Mare Suurhallis
Sakurai, Yoshihisa; Fujita, Zenya; Ishige, Yusuke
This study aims to develop and validate an automated system for identifying skating-style cross-country subtechniques using inertial sensors. In the first experiment, the performance of a male cross-country skier was used to develop an automated identification system. In the second, eight male and seven female college cross-country skiers participated to validate the developed identification system. Each subject wore inertial sensors on both wrists and both roller skis, and a small video camera on a backpack. All subjects skied through a 3450 m roller ski course using a skating style at their maximum speed. The adopted subtechniques were identified by the automated method based on the data obtained from the sensors, as well as by visual observations from a video recording of the same ski run. The system correctly identified 6418 subtechniques from a total of 6768 cycles, which indicates an accuracy of 94.8%. The precisions of the automatic system for identifying the V1R, V1L, V2R, V2L, V2AR, and V2AL subtechniques were 87.6%, 87.0%, 97.5%, 97.8%, 92.1%, and 92.0%, respectively. Most incorrect identification cases occurred during a subtechnique identification that included a transition and turn event. Identification accuracy can be improved by separately identifying transition and turn events. This system could be used to evaluate each skier’s subtechniques in course conditions. PMID:27049388
Full Text Available This study aims to develop and validate an automated system for identifying skating-style cross-country subtechniques using inertial sensors. In the first experiment, the performance of a male cross-country skier was used to develop an automated identification system. In the second, eight male and seven female college cross-country skiers participated to validate the developed identification system. Each subject wore inertial sensors on both wrists and both roller skis, and a small video camera on a backpack. All subjects skied through a 3450 m roller ski course using a skating style at their maximum speed. The adopted subtechniques were identified by the automated method based on the data obtained from the sensors, as well as by visual observations from a video recording of the same ski run. The system correctly identified 6418 subtechniques from a total of 6768 cycles, which indicates an accuracy of 94.8%. The precisions of the automatic system for identifying the V1R, V1L, V2R, V2L, V2AR, and V2AL subtechniques were 87.6%, 87.0%, 97.5%, 97.8%, 92.1%, and 92.0%, respectively. Most incorrect identification cases occurred during a subtechnique identification that included a transition and turn event. Identification accuracy can be improved by separately identifying transition and turn events. This system could be used to evaluate each skier’s subtechniques in course conditions.
Bernardi, Marco; Janssen, Thomas; Bortolan, Lorenzo; Pellegrini, Barbara; Fischer, Gabriela; Schena, Federico
The study had three purposes: to verify a hypothesized speed decrease during the 15km cross-country sit skiing (CCSS) race; documenting this possible fatigue effect (speed decrease), to evaluate changes among the four laps in kinematics parameters (cycle speed, cycle duration, cycle length, duty
Karaman, Ivo M.
Full Text Available Balkan populations of Rafalskia olympica (Kulczyński, 1903 are distinguished as separate subspecies Rafalskia olympica bulgarica Staręga, 1963 nov. stat.. Certain novel details of the R. olympica female body structure are presented. It is stated that Metaplatybunus drenskii Šilhavý, 1965 in not a synonym of R. olympica.
Köhne, Jessica L; Ormsbee, Michael J; McKune, Andrew J
The effects of a multi-ingredient performance supplement (MIPS) on markers of inflammation and muscle damage, perceived soreness and lower limb performance are unknown in endurance-trained female athletes. The purpose of this study was to determine the impact of MIPS (NO-Shotgun®) pre-loaded 4 weeks prior to a single-bout of downhill running (DHR) on hsC-Reactive Protein (hsCRP), interleukin (IL)-6, creatine kinase (CK), muscle soreness, lower limb circumferences and performance. Trained female runners ( n = 8; 29 ± 5.9 years) (VO 2max : ≥ 50 ml -1 .kg -1 .min -1 , midfollicular phase (7-11 days post-menses) were randomly assigned in a double-blind manner into two groups: MIPS ( n = 4) ingested one serving of NO Shotgun daily for 28 days prior to DHR and 30 min prior to all post-testing visits; Control (CON) ( n = 4) consumed an isocaloric maltodextrin placebo in an identical manner to MIPS. hsCRP, IL-6, CK, perceived soreness, limb circumferences, and performance measures (flexibility, squat jump peak power) were tested on 5 occasions; immediately before (PRE), immediately post-DHR, 24, 48 and 72 h post-DHR. There were main effects of time for CK ( p = 0.05), pain pressure threshold (right tibialis anterior ( p = 0.010), right biceps femoris ( p = 0.01), and left iliotibial band (ITB) ( p = 0.05) across all time points), and maximum squat jump power ( p = 0.04). Compared with 24 h post-DHR, maximum squat jump power was significantly lower at 48 h post-DHR ( p = 0.05). Lower body perceived soreness was significantly increased at 24 h ( p = 0.02) and baseline to 48 h ( p = 0.02) post DHR. IL-6 peaked immediately post-DHR ( p = 0.03) and hsCRP peaked at 24 h post-DHR ( p = 0.06). Calculation of effect sizes indicated a moderate attenuation of hsCRP in MIPS at 72 h post-DHR. Consumption of MIPS for 4 weeks prior to a single bout of DHR attenuated inflammation three days post, but did
Alexandru Lucian MIHAI
This paper presents a brief overview of a significant element of the sport marketing management model called the marketing mix. The marketing mix is crucial because it defines the sport business, and much of the sport marketer’s time is spent on various functions within the marketing mix. The marketing mix is the strategic combination of the product, price, place and promotion elements. These elements are typically called the four Ps of marketing. Decisions and strategies for each are importa...
Myer, Gregory D.; Jayanthi, Neeru; DiFiori, John P.; Faigenbaum, Avery D.; Kiefer, Adam W.; Logerstedt, David; Micheli, Lyle J.
Context: Many coaches, parents, and children believe that the best way to develop elite athletes is for them to participate in only 1 sport from an early age and to play it year-round. However, emerging evidence to the contrary indicates that efforts to specialize in 1 sport may reduce opportunities for all children to participate in a diverse year-round sports season and can lead to lost development of lifetime sports skills. Early sports specialization may also reduce motor skill development and ongoing participation in games and sports as a lifestyle choice. The purpose of this review is to employ the current literature to provide evidence-based alternative strategies that may help to optimize opportunities for all aspiring young athletes to maximize their health, fitness, and sports performance. Evidence Acquisition: Nonsystematic review with critical appraisal of existing literature. Study Design: Clinical review. Level of Evidence: Level 4. Conclusion: Based on the current evidence, parents and educators should help provide opportunities for free unstructured play to improve motor skill development and youth should be encouraged to participate in a variety of sports during their growing years to influence the development of diverse motor skills. For those children who do choose to specialize in a single sport, periods of intense training and specialized sport activities should be closely monitored for indicators of burnout, overuse injury, or potential decrements in performance due to overtraining. Last, the evidence indicates that all youth should be involved in periodized strength and conditioning (eg, integrative neuromuscular training) to help them prepare for the demands of competitive sport participation, and youth who specialize in a single sport should plan periods of isolated and focused integrative neuromuscular training to enhance diverse motor skill development and reduce injury risk factors. Strength of Recommendation Taxonomy (SORT): B. PMID
Gabus, Vincent; Monney, Pierre
Physical activity is beneficial for health and the cardiovascular risk profile. However, it can be dangerous in people with cardiac disease that might be asymptomatic. Individuals of all ages and all levels engage in sporting activities. The medical approach is different whether one evaluates a young competitive athlete, a sedentary adult who wants to start a recreational sport or a patient with heart disease who wishes to engage in sport. This article summarizes the various recommendations on the subject.