Showing papers in "Journal of Sports Sciences in 2004"
TL;DR: The evidence concerning the links between physical activity and cardiovascular disease, overweight and obesity, psychosocial measures, type II diabetes, and skeletal health is reviewed, and several factors lead to the conclusion that promoting physical activity in youth is desirable.
Abstract: We provide a wide-ranging review of health-related physical activity in children and adolescents using a behavioural epidemiology framework. In contrast to many other reviews, we highlight issues associated with true sedentary behaviours alongside physically active behaviours. Specifically, we review the evidence concerning the links between physical activity and cardiovascular disease, overweight and obesity, psychosocial measures, type II diabetes, and skeletal health. Although the evidence is unconvincing at times, several factors lead to the conclusion that promoting physical activity in youth is desirable. A review of the prevalence of physical activity and sedentary behaviours shows that many young people are active, but this declines with age. A substantial number are not adequately active for health benefits and current trends in juvenile obesity are a cause for concern. Prevalence data on sedentary behaviours are less extensive but suggest that total media use by young people has not changed greatly in recent years. Most children and adolescents do not exceed recommended daily hours of TV viewing. Physical activity is unrelated to TV viewing. We also identified the key determinants of physical activity in this age group, highlighting demographic, biological, psychological, behavioural, social and environmental determinants. Interventions were considered for school, family and community environments. Finally, policy recommendations are offered for the education, governmental, sport and recreation, health, and mass media sectors.
943 citations
TL;DR: The evidence for a causal relationship between sedentary behaviour/physical activity programmes and cardiovascular, musculoskeletal and psycho-social health, independent living and health-related quality of life into old age is considered.
Abstract: The purpose of this multidisciplinary review paper is to critically review evidence from descriptive, efficacy and effectiveness studies concerned with physical activity and older people. Both levels of fitness (aerobic power, strength, flexibility and functional capability) and measures of physical activity involvement decline with age, and the extent to which this is due to a biological ageing processes or disuse (physical inactivity) is critically examined. The review will consider the evidence for a causal relationship between sedentary behaviour/physical activity programmes and cardiovascular, musculoskeletal and psycho-social health, independent living and health-related quality of life into old age. The review also considers the effectiveness of different physical activity interventions for older people and issues relating to cost-effectiveness. The implications for future policy in terms of research, health care services, and education and training are briefly discussed.
600 citations
TL;DR: The amounts of water, carbohydrate and salt that athletes are advised to ingest during exercise are based upon their effectiveness in attenuating both fatigue as well as illness due to hyperthermia, dehydration or hyperhydration.
Abstract: The amounts of water, carbohydrate and salt that athletes are advised to ingest during exercise are based upon their effectiveness in attenuating both fatigue as well as illness due to hyperthermia, dehydration or hyperhydration. When possible, fluid should be ingested at rates that most closely match sweating rate. When that is not possible or practical or sufficiently ergogenic, some athletes might tolerate body water losses amounting to 2% of body weight without significant risk to physical well-being or performance when the environment is cold (e.g. 5–10°C) or temperate (e.g. 21–22°C). However, when exercising in a hot environment ( >30°C), dehydration by 2% of body weight impairs absolute power production and predisposes individuals to heat injury. Fluid should not be ingested at rates in excess of sweating rate and thus body water and weight should not increase during exercise. Fatigue can be reduced by adding carbohydrate to the fluids consumed so that 30–60 g of rapidly absorbed carbohydrate are i...
459 citations
TL;DR: It is proposed that talent needs to be reconceptualized so that talent identification and talent development processes are perceived to be dynamic and interrelated, and the need to place greater emphasis on the capacity of a child to develop in sport and the psychological factors that underpin this process is highlighted.
Abstract: It is acknowledged that appropriate support and training are essential if talented individuals are to fulfil their potential. The early identification of talented athletes is an increasingly important consideration for researchers and practitioners alike. Once talented individuals have been detected, crucial but limited support resources can be optimally deployed to ensure that their needs are met and that their gifts are developed. However, there is considerable disagreement among experts on what talent is, and which factors can reliably be used within talent identification processes. This paper explores prerequisites to success in sport, and the comparative efficacy of employing these prerequisites within talent identification schemes. It is proposed that talent needs to be reconceptualized so that talent identification and talent development processes are perceived to be dynamic and interrelated. Additionally, the need to place greater emphasis on the capacity of a child to develop in sport and the psychological factors that underpin this process is highlighted. To this end, it is advocated that talent identification and development schemes, while emphasizing the multidimensional nature of talent, need to recognize the essential role of psychology in the ability of individuals to fulfil their sporting potential.
458 citations
TL;DR: The results suggest that the motion activities of an elite field-hockey competition are similar to those of elite soccer, rugby and Australian Rules football.
Abstract: Limited information exists about the movement patterns of field-hockey players, especially during elite competition. Time–motion analysis was used to document the movement patterns during an intern...
443 citations
TL;DR: Although there is new interest in the recovery of intramuscular triglyceride stores between training sessions, there is no evidence that diets which are high in fat and restricted in carbohydrate enhance training.
Abstract: An important goal of the athlete's everyday diet is to provide the muscle with substrates to fuel the training programme that will achieve optimal adaptation for performance enhancements. In reviewing the scientific literature on post-exercise glycogen storage since 1991, the following guidelines for the training diet are proposed. Athletes should aim to achieve carbohydrate intakes to meet the fuel requirements of their training programme and to optimize restoration of muscle glycogen stores between workouts. General recommendations can be provided, preferably in terms of grams of carbohydrate per kilogram of the athlete's body mass, but should be fine-tuned with individual consideration of total energy needs, specific training needs and feedback from training performance. It is valuable to choose nutrient-rich carbohydrate foods and to add other foods to recovery meals and snacks to provide a good source of protein and other nutrients. These nutrients may assist in other recovery processes and, in the case of protein, may promote additional glycogen recovery when carbohydrate intake is suboptimal or when frequent snacking is not possible. When the period between exercise sessions is < 8 h, the athlete should begin carbohydrate intake as soon as practical after the first workout to maximize the effective recovery time between sessions. There may be some advantages in meeting carbohydrate intake targets as a series of snacks during the early recovery phase, but during longer recovery periods (24 h) the athlete should organize the pattern and timing of carbohydrate-rich meals and snacks according to what is practical and comfortable for their individual situation. Carbohydrate-rich foods with a moderate to high glycaemic index provide a readily available source of carbohydrate for muscle glycogen synthesis, and should be the major carbohydrate choices in recovery meals. Although there is new interest in the recovery of intramuscular triglyceride stores between training sessions, there is no evidence that diets which are high in fat and restricted in carbohydrate enhance training.
410 citations
TL;DR: To optimize the physical preparation of top-class match officials, the results of this study support the application of intensive and intermittent training sessions, which should place priority on high-intensity aerobic stimuli.
Abstract: The aim of this study was to examine the physical and perceptual-cognitive demands imposed on UEFA top-class referees and assistant referees during the final round of the Euro 2000 Championship. To investigate the physical workload, the heart rates during matches were monitored by short-range radio telemetry and translated to different workloads expressed as a percentage of maximal heart rate. For measurement of the perceptual-cognitive workload, video-recordings of games were used to obtain the average number of observable decisions taken by a referee. On average, referees and assistant referees performed the matches at 85±5% and 77±7% of their maximal heart rate, respectively. Over the 31 games, the mean number of observable decisions was 137 (range 104–162), 64% of which were based on communication with the assistant referees and/or the fourth official. To optimize the physical preparation of top-class match officials, the results of this study support the application of intensive and intermittent trai...
314 citations
TL;DR: To maintain immune function, athletes should eat a well-balanced diet sufficient to meet their energy requirements, and consuming 30–60 g carbohydrate during sustained intensive exercise attenuates rises in stress hormones such as cortisol and appears to limit the degree of exercise-induced immune depression.
Abstract: Strenuous bouts of prolonged exercise and heavy training are associated with depressed immune cell function. Furthermore, inadequate or inappropriate nutrition can compound the negative influence of heavy exertion on immunocompetence. Dietary deficiencies of protein and specific micronutrients have long been associated with immune dysfunction. An adequate intake of iron, zinc and vitamins A, E, B6 and B12 is particularly important for the maintenance of immune function, but excess intakes of some micronutrients can also impair immune function and have other adverse effects on health. Immune system depression has also been associated with an excess intake of fat. To maintain immune function, athletes should eat a well-balanced diet sufficient to meet their energy requirements. An athlete exercising in a carbohydrate-depleted state experiences larger increases in circulating stress hormones and a greater perturbation of several immune function indices. Conversely, consuming 30–60 g carbohydrate · h−1 during...
307 citations
TL;DR: There is limited evidence that dietary supplementation with antioxidants will improve human performance, and it is currently unclear whether regular vigorous exercise increases the need for dietary intake of antioxidants.
Abstract: Muscular exercise promotes the production of radicals and other reactive oxygen species in the working muscle. Growing evidence indicates that reactive oxygen species are responsible for exercise-i...
291 citations
TL;DR: Skinfolds and urinary ketones may be the best biomarkers of fat stores and carbohydrate deficiency, respectively, and research is needed to identify and validate these and other markers.
Abstract: Many athletes, especially female athletes and participants in endurance and aesthetic sports and sports with weight classes, are chronically energy deficient. This energy deficiency impairs performance, growth and health. Reproductive disorders in female athletes are caused by low energy availability (defined as dietary energy intake minus exercise energy expenditure), perhaps specifically by low carbohydrate availability, and not by the stress of exercise. These reproductive disorders can be prevented or reversed by dietary supplementation in compensation for exercise energy expenditure without any moderation of the exercise regimen. Energy balance is not the objective of athletic training. To maximize performance, athletes strive to achieve an optimum sport-specific body size, body composition and mix of energy stores. To pursue these objectives, athletes need to manage fat, protein and carbohydrate balances separately, but it is impractical for athletes to monitor these balances directly, and appetite ...
285 citations
TL;DR: Campaigns should focus more on influencing proximal variables, such as social norms, to bring about long-term behaviour change, and Evaluation designs that measure the full range of variables are preferred to an over-concentration on behaviour alone.
Abstract: Mass media campaigns are conducted to influence community norms around health behaviours, including physical activity Campaigns can reach large populations at relatively low cost, to influence awareness, knowledge and beliefs through to intention and behaviour change We reviewed 15 campaigns with an explicit focus on physical activity, and explored impacts upon a range of proximal and distal variables Campaigns achieved high recall, with a median of 70% of the target group aware of the campaign Increases in knowledge or attitudes to physical activity were found among half the campaigns that reported this measure Few campaigns reported other proximal variables, such as saliency, beliefs, self-efficacy or behavioural intention Increases in physical activity were reported among motivated sub-groups of volunteers, but few campaigns reported population increases in activity Campaigns increase awareness of the issue of physical activity but may not have a population-level effect on behaviour Campaigns should focus more on influencing proximal variables, such as social norms, to bring about long-term behaviour change This should be seen as part of a broader strategy, including policy and environmental change Evaluation designs that measure the full range of variables are preferred to an over-concentration on behaviour alone
TL;DR: There is limited evidence for harmful effects of a high protein intake and there is a metabolic rationale for the efficacy of an increase in protein, if muscle hypertrophy is the goal, a higher protein intake within the context of an athlete's overall dietary requirements may be beneficial.
Abstract: The main determinants of an athlete's protein needs are their training regime and habitual nutrient intake. Most athletes ingest sufficient protein in their habitual diet. Additional protein will c...
TL;DR: It is suggested that as the intensity, duration and load of rugby league training sessions and matches is increased, the incidence of injury is also increased.
Abstract: The aim of this study was to examine the influence of perceived intensity, duration and load of matches and training on the incidence of injury in rugby league players. The incidence of injury was ...
TL;DR: This article used repeated-measures mixed modeling to analyse 676 official race times of 26 US and 25 Australian Olympic swimmers in the 12-month period leading up to the 2000 Olympic Games.
Abstract: Estimates of progression and variability of athletic performance in competitions are useful for researchers and practitioners interested in factors that affect performance. We used repeated-measures mixed modelling to analyse 676 official race times of 26 US and 25 Australian Olympic swimmers in the 12-month period leading up to the 2000 Olympic Games. Progression was expressed as percent changes in mean performance; variability was expressed as the coefficient of variation in performance of an individual swimmer between races. Within competitions, both nations showed similar improvements in mean time from heats through finals (overall 1.2%; 95% confidence limits 1.1 to 1.3%). Mean competition time also improved over 12 months by a similar amount in both nations (0.9%; 95% confidence limits 0.6 to 1.2%). The US swimmers showed a greater improvement between the finals (a difference of 0.5%; 95% confidence limits −0.2 to 1.1%), which paralleled changes in the medal haul of the two nations. The coefficient o...
TL;DR: Age discriminated between the two groups, indicating that the elite youth players were younger than the sub-elite players, and more attention has to be paid to tactical qualities, motivation and specific technical skills.
Abstract: To determine the relationship between multidimensional performance characteristics and level of performance in talented youth field hockey players, elite youth players (n = 38, mean age 13.2 years, s = 1.26) were compared with sub-elite youth players (n = 88, mean age 14.2 years, s = 1.26) on anthropometric, physiological, technical, tactical and psychological characteristics. Multivariate analyses with performance level and gender as factors, and age as the covariate, showed that the elite youth players scored better than the sub-elite youth players on technical (dribble performance in a peak and repeated shuttle run), tactical (general tactics; tactics for possession and non-possession of the ball) and psychological variables (motivation) (P < 0.05). The most discriminating variables were tactics for possession of the ball, motivation and performance in a slalom dribble. Age discriminated between the two groups, indicating that the elite youth players were younger than the sub-elite players. In the guidance of young talented players to the top as well as in the detection of talented players, more attention has to be paid to tactical qualities, motivation and specific technical skills.
TL;DR: Although an increase in plasma insulin following carbohydrate ingestion in the hour before exercise inhibits lipolysis and liver glucose output, and can lead to transient hypoglycaemia during subsequent exercise in susceptible individuals, there is no convincing evidence that this is always associated with impaired exercise performance.
Abstract: A key goal of pre-exercise nutritional strategies is to maximize carbohydrate stores, thereby minimizing the ergolytic effects of carbohydrate depletion. Increased dietary carbohydrate intake in the days before competition increases muscle glycogen levels and enhances exercise performance in endurance events lasting 90 min or more. Ingestion of carbohydrate 3-4 h before exercise increases liver and muscle glycogen and enhances subsequent endurance exercise performance. The effects of carbohydrate ingestion on blood glucose and free fatty acid concentrations and carbohydrate oxidation during exercise persist for at least 6 h. Although an increase in plasma insulin following carbohydrate ingestion in the hour before exercise inhibits lipolysis and liver glucose output, and can lead to transient hypoglycaemia during subsequent exercise in susceptible individuals, there is no convincing evidence that this is always associated with impaired exercise performance. However, individual experience should inform individual practice. Interventions to increase fat availability before exercise have been shown to reduce carbohydrate utilization during exercise, but do not appear to have ergogenic benefits.
TL;DR: Post-exercise restoration of fluid balance after sweat-induced dehydration avoids the detrimental effects of a body water deficit on physiological function and subsequent exercise performance.
Abstract: For a person undertaking regular exercise, any fluid deficit that is incurred during one exercise session can potentially compromise the next exercise session if adequate fluid replacement does not occur. Fluid replacement after exercise can, therefore, frequently be thought of as hydration before the next exercise bout. The importance of ensuring euhydration before exercise and the potential benefits of temporary hyperhydration with sodium salts or glycerol solutions are also important issues. Post-exercise restoration of fluid balance after sweat-induced dehydration avoids the detrimental effects of a body water deficit on physiological function and subsequent exercise performance. For effective restoration of fluid balance, the consumption of a volume of fluid in excess of the sweat loss and replacement of electrolyte, particularly sodium, losses are essential. Intravenous fluid replacement after exercise has been investigated to a lesser extent and its role for fluid replacement in the dehydrated but otherwise well athlete remains equivocal.
TL;DR: Exposure to hypoxia appears to have some positive transfer effects on subsequent training in normoxia during and after HiLo, thereby increasing the potential to improve some neuromuscular and cardiovascular determinants of endurance performance.
Abstract: The benefits of living and training at altitude (HiHi) for an improved altitude performance of athletes are clear, but controlled studies for an improved sea-level performance are controversial. The reasons for not having a positive effect of HiHi include: (1) the acclimatization effect may have been insufficient for elite athletes to stimulate an increase in red cell mass/haemoglobin mass because of too low an altitude (<2000-2200 m) and/or too short an altitude training period (<3-4 weeks); (2) the training effect at altitude may have been compromised due to insufficient training stimuli for enhancing the function of the neuromuscular and cardiovascular systems; and (3) enhanced stress with possible overtraining symptoms and an increased frequency of infections. Moreover, the effects of hypoxia in the brain may influence both training intensity and physiological responses during training at altitude. Thus, interrupting hypoxic exposure by training in normoxia may be a key factor in avoiding or minimizin...
TL;DR: It is suggested that high-intensity cycling performance can be increased following moderate caffeine ingestion and that this improvement may be related to a reduction in RPE and an elevation in blood lactate concentration.
Abstract: The aim of this study was to determine the effects of caffeine ingestion on a 'preloaded' protocol that involved cycling for 2 min at a constant rate of 100% maximal power output immediately followed by a 1-min 'all-out' effort. Eleven male cyclists completed a ramp test to measure maximal power output. On two other occasions, the participants ingested caffeine (5 mg. kg(-1)) or placebo in a randomized, double-blind procedure. All tests were conducted on the participants' own bicycles using a Kingcycle test rig. Ratings of perceived exertion (RPE; 6-20 Borg scale) were lower in the caffeine trial by approximately 1 RPE point at 30, 60 and 120 s during the constant rate phase of the preloaded test (P <0.05). The mean power output during the all-out effort was increased following caffeine ingestion compared with placebo (794+/-164 vs 750+/-163 W; P=0.05). Blood lactate concentration 4, 5 and 6 min after exercise was also significantly higher by approximately 1 mmol. l(-1) in the caffeine trial (P <0.05). These results suggest that high-intensity cycling performance can be increased following moderate caffeine ingestion and that this improvement may be related to a reduction in RPE and an elevation in blood lactate concentration.
TL;DR: It is recommended that fewer swim events be used in the process of selecting young water-polo players, and that greater emphasis should be placed on evaluation of game intelligence.
Abstract: The processes of talent detection and early development are critical in any sport programme However, not much is known about the appropriate strategies to be implemented during these processes, and little scientific inquiry has been conducted in this area The aim of this study was to identify variables of swimming, ball handling and physical ability, as well as game intelligence, which could assist in the selection process of young water-polo players Twenty-four players aged 14-15 years underwent a battery of tests three times during a 2-year period, before selection to the junior national team The tests included: freestyle swim for 50, 100, 200 and 400 m, 100-m breast-stroke, 100-m 'butterfly' (with breast-stroke leg motion), 50-m dribbling, throwing at the goal, throw for distance in the water, vertical 'jump' from the water, and evaluation of game intelligence by two coaches A comparison of those players eventually selected to the team and those not selected demonstrated that, 2 years before selection, selected players were already superior on most of the swim tasks (with the exception of breast-stroke and 50-m freestyle), as well as dribbling and game intelligence This superiority was maintained throughout the 2 years Two-way tabulation revealed that, based on baseline scores, the prediction for 67% of the players was in agreement with the final selection to the junior national team We recommend that fewer swim events be used in the process of selecting young water-polo players, and that greater emphasis should be placed on evaluation of game intelligence
TL;DR: It is suggested that, in terms of saliva secretion, sIgA and alpha-amylase responses, a 3 h rest is enough to recover from previous strenuous exercise.
Abstract: The purpose of this study was to establish the effect of exercise at different times of day on saliva flow rate, immunoglobulin A (sIgA) concentration and secretion rate, and alpha-amylase activity, and to establish how these parameters change following a second exercise bout performed on the same day. In a counterbalanced design, eight male volunteers participated in three experimental trials separated by at least 4 days. On the trial with afternoon exercise only, the participants cycled for 2 h at 60% VO2max starting at 14:00 h. On the other two trials, participants performed either two bouts of exercise at 60% VO2max for 2 h (the first started at 09:00 h and the second started at 14:00 h) or a separate resting trial. Unstimulated saliva samples were obtained 10 min before exercise, after 58 - 60 min and during the last 2 min of exercise, and at 1 h and 2 h after exercise. Venous blood samples were taken 5 min before exercise and immediately after exercise for both bouts. Participants remained fasted between 23:00 h on the day before the trials and 18:00 h on the day of the trial. Circadian variations were found in sIgA concentration, which decreased with time from its highest value in the early morning to its lowest value in the evening, and salivary alpha-amylase secretion rate, which increased from its lowest value in the morning to its highest value in the late afternoon. Cycling at 60% VO2max for 2 h significantly decreased saliva flow rate, increased sIgA concentration and alpha-amylase activity, but did not influence sIgA secretion rate. Performing prolonged cycling at different times of day did not differentially affect the salivary and plasma hormonal responses in the short term. Performance of a second prolonged exercise bout elicited a greater plasma stress hormone response but did not appear to compromise oral immunity acutely. These findings also suggest that, in terms of saliva secretion, sIgA and alpha-amylase responses, a 3 h rest is enough to recover from previous strenuous exercise. During such exercise, sympathetic stimulation appears to be strong enough to inhibit saliva flow rate; however, it appears that it does not increase sIgA output via transcytosis.
TL;DR: The results showed that moderate-intensity exercise improves cognitive performance and that low- intensity exercise enables participants to compensate the negative dual-task effect.
Abstract: The aim of this study was to examine the facilitating effects of moderate physical exercise on the reaction process to gain a better understanding of the interaction between physiological and cogni...
TL;DR: By adjusting the control and order parameters within the context of a specific race distance, both coach and swimmer will be able to detect the best adapted pattern for a given race pace and follow how arm coordination changes over the course of training.
Abstract: We examined the preferred mode of arm coordination in 14 elite male front-crawl swimmers. Each swimmer performed eight successive swim trials in which target velocity increased from the swimmer's u...
TL;DR: The instructional set of the Vividness of Movement Imagery Questionnaire was changed to make the participant the ‘agent’ of the external visual perspective images rather than somebody else, indicating a significant correlation between external visual imagery and kinaesthetic imagery.
Abstract: In two studies, we examined the strength of relationship between internal and external visual imagery with kinaesthetic imagery. In Study 1, 56 participants completed the Vividness of Movement Imagery Questionnaire and the Movement Imagery Questionnaire. Pearson's product–moment correlations failed to reveal a significant correlation between external visual imagery and kinaesthetic imagery. However, the correlation between internal visual imagery and kinaesthetic imagery approached significance. In Study 2, the instructional set of the Vividness of Movement Imagery Questionnaire was changed to make the participant the ‘agent’ of the external visual perspective images rather than somebody else. Sixty-four participants completed the two questionnaires. The results indicated a significant correlation between external visual imagery and kinaesthetic imagery (r = 0.60, P 0.01). The result...
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TL;DR: Sleep loss and its effects are important components of jet lag, and attempts to promote sleep by the use of melatonin and other hypnotics are also relevant.
Abstract: International travel is an essential part of the life of elite athletes, both for competition and training. It is also becoming increasingly common among recreational sportspersons. Long-distance travel is associated with a group of transient negative effects, collectively referred to as 'travel fatigue', which result from anxiety about the journey, the change to an individual's daily routine, and dehydration due to time spent in the dry air of the aircraft cabin. Travel fatigue lasts for only a day or so, but for those who fly across several time zones, there are also the longer-lasting difficulties associated with 'jet lag'. The problems of jet lag can last for over a week if the flight crosses 10 time zones or more, and they can reduce performance and the motivation to train effectively. Knowledge of the properties of the body clock enables the cause of the difficulties to be understood (an unadjusted body clock), and forms the basis of using light in the new time zone to promote adjustment of the body clock. Sleep loss and its effects are important components of jet lag, and attempts to promote sleep by the use of melatonin and other hypnotics are also relevant. Sleep loss is also found in those who undertake challenges that involve long periods where the normal consolidated sleep of 8 h length is not possible. Advice on sleep regimens in such circumstances is given.
TL;DR: The skilled Soccer and hockey players were quicker than the skilled volleyball players at recognizing structured soccer and hockey action sequences and the skilled field hockey and soccer players were able to transfer perceptual information or strategies between their respective sports.
Abstract: The ability to recognize patterns of play is fundamental to performance in team sports. While typically assumed to be domain-specific, pattern recognition skills may transfer from one sport to another if similarities exist in the perceptual features and their relations and/or the strategies used to encode and retrieve relevant information. A transfer paradigm was employed to compare skilled and less skilled soccer, field hockey and volleyball players' pattern recognition skills. Participants viewed structured and unstructured action sequences from each sport, half of which were randomly represented with clips not previously seen. The task was to identify previously viewed action sequences quickly and accurately. Transfer of pattern recognition skill was dependent on the participant's skill, sport practised, nature of the task and degree of structure. The skilled soccer and hockey players were quicker than the skilled volleyball players at recognizing structured soccer and hockey action sequences. Performance differences were not observed on the structured volleyball trials between the skilled soccer, field hockey and volleyball players. The skilled field hockey and soccer players were able to transfer perceptual information or strategies between their respective sports. The less skilled participants' results were less clear. Implications for domain-specific expertise, transfer and diversity across domains are discussed.
TL;DR: Optimum fluid replacement strategies will depend on the exercise task, the environmental conditions and the individual physiological characteristics of the athlete, and may be a strategy that can be used by athletes competing in stressful environments.
Abstract: Exercise in the heat poses a formidable challenge to the body's ability to control its internal environment due to the high rates of metabolic heat production and heat gain by physical transfer from the environment. In an attempt to restrict the rise in core temperature, an increased rate of sweat secretion onto the skin is invoked. This may limit the rise in core temperature, and can prolong the time before a limiting temperature is attained, but it does so at the cost of a loss of body water and electrolytes. The effects of the diminished blood volume are offset to some extent by cardiovascular adaptations, including an increased heart rate and an increased peripheral resistance, but these are insufficient to maintain functional capacity when blood volume is reduced. Prior dehydration will impair performance in both prolonged exercise and short-term high-intensity exercise. Athletes living and training in the heat may experience chronic hypohydration due to inadequate replacement of fluid losses. The negative consequences of exercise in the heat are attenuated to some extent by a period of adaptation, and by the ingestion of water or other appropriate fluids. Optimum fluid replacement strategies will depend on the exercise task, the environmental conditions and the individual physiological characteristics of the athlete. Manipulation of pre-exercise body temperature can also influence exercise performance and may be a strategy that can be used by athletes competing in stressful environments.
TL;DR: Six barrier dimensions emerged from the interview data: negative perceptions of psychology, lack of sport psychology knowledge, integrating with players and coaching staff, role and service clarity, practical constraints, and perceived value of sport Psychology.
Abstract: The aim of the present study was to examine knowledge and perceptions of applied sport psychology within English soccer. National coaches (n = 8), youth academy directors (n = 21) and academy coaches (n = 27) were surveyed using questionnaire and interview methods. Questionnaire results revealed a lack of knowledge of sport psychology that appeared to underpin some of the most significant barriers to entry for sport psychologists. These included lack of clarity concerning the services of a sport psychologist, problems fitting in and players' negative perceptions of sport psychology. Overall, however, lack of finance was the highest rated barrier. Six barrier dimensions emerged from the interview data: negative perceptions of psychology, lack of sport psychology knowledge, integrating with players and coaching staff, role and service clarity, practical constraints, and perceived value of sport psychology. These findings were broadly compatible with the survey data, with finance emerging as a major barrier and misconceptions of sport psychology being common. Our conclusions are discussed in relation to the practical implications of the study for both applied research and the provision of sport psychology services within English soccer.
TL;DR: It is concluded that the performance of elite female wheelchair basketball players is dependent on functional ability, and high point players to perform better compared with low point players for the majority of variables determining the quality of game performance.
Abstract: The functional classification system for wheelchair basketball is based on an analysis of the players' functional resources through field-testing and game observation. Under this system, players are assigned a score of 1 to 4.5. The aim of this study was to determine if the wheelchair basketball player classification system reflects the existing differences in performance of elite female players. During the World Championship for Wheelchair Basketball in Sydney 1998, eight teams were videotaped for three 40-min games for a total of 120 min per team. Fifty-nine female players (Class I [1 and 1.5 points] n = 12; Class II [2 and 2.5 points] n = 20; Class III [3 and 3.5 points] n = 13; Class IV [4 and 4.5 points] n = 14) were retained for a detailed performance analysis by means of the Comprehensive Basketball Grading System (CBGS). Two-way analysis of variance showed high point players to perform better compared with low point players for the majority of variables determining the quality of game performance....
TL;DR: The results suggest that the specific status of the participants with respect to training, resistance or endurance is important for the magnitude of the neuromuscular, physiological and performance differences observed between weightlifters and road cyclists.
Abstract: Maximal strength, power, muscle cross-sectional area, maximal and submaximal cycling endurance characteristics and serum hormone concentrations of testosterone, free testosterone and cortisol were ...