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1.
Abstract

Ten moderately well-conditioned male students at the University of Toledo ran on a treadmill, fully attired in football equipment, with an environmental temperature of 90 F and relative humidity of 70%. Each subject was partially acclimatized and then exposed to the experimental conditions on five consecutive days (balanced Latin square). Four 1-liter water replacement schedules (designed to test specific hypotheses), and a control of no water, served as five levels of the independent variable. Data were collected on rectal temperature, heart rate, pulse pressure, specific gravity changes for whole blood and for plasma, and sweat loss. Results showed that water ingestion early during the work session combated the effects of heat stress better than late administration; however, this advantage was reduced toward the end of the work session. The results were mixed concerning the relative merits of ingesting the water in one or two administrations.  相似文献   

2.
ABSTRACT

The purpose of this study was to expand our previously published sweat normative data/analysis (n = 506) to establish sport-specific normative data for whole-body sweating rate (WBSR), sweat [Na+], and rate of sweat Na+ loss (RSSL). Data from 1303 athletes were compiled from observational testing (2000–2017) using a standardized absorbent sweat patch technique to determine local sweat [Na+] and normalized to whole-body sweat [Na+]. WBSR was determined from change in exercise body mass, corrected for food/fluid intake and urine/stool loss. RSSL was the product of sweat [Na+] and WBSR. There were significant differences between sports for WBSR, with highest losses in American football (1.51 ± 0.70 L/h), then endurance (1.28 ± 0.57 L/h), followed by basketball (0.95 ± 0.42 L/h), soccer (0.94 ± 0.38 L/h) and baseball (0.83 ± 0.34 L/h). For RSSL, American football (55.9 ± 36.8 mmol/h) and endurance (51.7 ± 27.8 mmol/h) were greater than soccer (34.6 ± 19.2 mmol/h), basketball (34.5 ± 21.2 mmol/h), and baseball (27.2 ± 14.7 mmol/h). After ANCOVA, significant between-sport differences in adjusted means for WBSR and RSSL remained. In summary, due to the significant sport-specific variation in WBSR and RSSL, American football and endurance have the greatest need for deliberate hydration strategies.

Abbreviations: WBSR: whole body sweating rate; SR: sweating rate; Na+: sodium; RSSL: rate of sweat sodium loss  相似文献   

3.
Abstract

The effects of breathing 100% oxygen on resting, exercise, and recovery oxygen consumptions, pulmonary ventilation volumes, and heart rates were observed on six highly conditioned male athletes. The subjects rode a bicycle ergometer at a heavy work load for five minutes, breathing either normal air or medical oxygen. Ventilation volumes were determined by the open-circuit Douglas bag method, measuring inspired and expired volumes. Gas samples were analyzed for nitrogen and oxygen concentrations on Van Slyke and Beckman gas analyzers, and heart rates were recorded via a telemetry-electrocardiograph system. The results indicated a substantial increase in resting oxygen consumption, a decrease in resting ventilation volume, a marked decline in exercise and recovery ventilation volumes, and an insignificant lowering of the energy cost of exercise during the oxygen experiments. No appreciable differences were noted in heart rates between the oxygen and air experiments.  相似文献   

4.
Abstract

This study investigated the effects of oral taurine supplementation on cycling time to exhaustion at a fixed-intensity and thermoregulation in the heat. In a double-blind, randomised crossover design, 11 healthy males participated in a time to exhaustion test in the heat (35°C, 40% RH), cycling at the power output associated with ventilatory threshold, 2?h after ingesting: Taurine (50?mg?kg?1) or placebo (3?mg?kg?1?maltodextrin). Core and mean skin temperature, mean sweat rate, heart rate, rating of perceived exertion (RPE), thermal comfort and thermal sensation were measured during exercise and blood lactate concentration (B[La]) was measured after exercise. Taurine supplementation increased time to exhaustion by 10% (25.16 min vs. 22.43 min, p?=?0.040), end sweat rate by 12.7% (687?nL?min?1 vs. 600?nL?min?1, p?=?0.034) and decreased B[La] by 16.5% (5.75?mmol?L?1 vs. 6.85?mmol?L?1, p?=?0.033). Core temperature was lower in the final 10% of the time to exhaustion (38.5°C vs. 38.1°C, p?=?0.049). Taurine supplementation increased time to exhaustion and local sweating, while decreasing RPE and core temperature in the later stages of exercise, as well as reducing post-exercise B[La]. This study provides the evidence of taurine's role in thermoregulatory processes. These findings have implications for the short-term preparation strategies of individuals exercising in the heat. Based on these findings, a single dose of taurine 2?h prior to training or competition would provide an ergogenic and thermoregulatory effect.  相似文献   

5.
Abstract

This study examined the relationship between intensity of training and changes in hydration status, core temperature, sweat rate and composition and fluid balance in professional football players training in the heat. Thirteen professional football players completed three training sessions; “higher-intensity” (140 min; HI140), “lower-intensity” (120 min; LI120) and “game-simulation” (100 min; GS100). Movement demands were measured by Global Positioning System, sweat rate and concentration were determined from dermal patches and body mass change. Despite similar environmental conditions (26.9 ± 0.1°C and 65.0 ± 7.0% relative humidity [Rh]), higher relative speeds (m · min?1) and increased perceptions of effort and thermal strain were observed in HI140 and GS100 compared with LI120 (P < 0.05). Significantly (P < 0.05) greater sweat rate (L · h?1) and electrolyte losses (g) were observed in HI140 and GS100 compared with LI120. Rate of rise in core temperature was correlated with mean speed (r = 0.85), session rating of perceived exertion (sRPE) (r = 0.61), loss of potassium (K+) (r = 0.51) sweat rate (r = 0.49), and total sweat loss (r = 0.53), with mean speed the strongest predictor. Sodium (Na+) (r = 0.39) and K+ (r = 0.50) losses were associated with total distance covered. In hot conditions, individualised rehydration practices should be adopted following football training to account for differences in sweat rate and electrolyte losses in response to intensity and overall activity within a session.  相似文献   

6.
AbstThis study examined the relationship between intensity of training and changes in hydration status, core temperature, sweat rate and composition and fluid balance in professional football players training in the heat. Thirteen professional football players completed three training sessions; "higher-intensity" (140 min; HI140), "lower-intensity" (120 min; LI120) and "game-simulation" (100 min; GS100). Movement demands were measured by Global Positioning System, sweat rate and concentration were determined from dermal patches and body mass change. Despite similar environmental conditions (26.9 ± 0.1 °C and 65.0 ± 7.0% relative humidity [Rh]), higher relative speeds (m · min(-1)) and increased perceptions of effort and thermal strain were observed in HI140 and GS100 compared with LI120 (P < 0.05). Significantly (P < 0.05) greater sweat rate (L · h(-1)) and electrolyte losses (g) were observed in HI140 and GS100 compared with LI120. Rate of rise in core temperature was correlated with mean speed (r = 0.85), session rating of perceived exertion (sRPE) (r = 0.61), loss of potassium (K+) (r = 0.51) sweat rate (r = 0.49), and total sweat loss (r = 0.53), with mean speed the strongest predictor. Sodium (Na+) (r = 0.39) and K+ (r = 0.50) losses were associated with total distance covered. In hot conditions, individualised rehydration practices should be adopted following football training to account for differences in sweat rate and electrolyte losses in response to intensity and overall activity within a session.  相似文献   

7.
Abstract

Pre-cooling studies report positive physiological and performance benefits in laboratory conditions, although research studies have not investigated these reported benefits in ecologically valid team-sport training and competition settings. Accordingly, this study investigated the effect of field-based pre-cooling strategies for professional football players during training and competition in the heat. Ten professional football players from an Australian A-League club performed two training sessions and competitive matches in hot ambient conditions (29±3oC, 78±8% relative humidity) with or without pre-cooling. The pre-cooling intervention involved 20-min of an ice-vest, cold towels and 350 mL ice-slushie drink. Training sessions (n=9) were randomised, and consisted of 2 x 10-min interval training, followed by 6 x 3-min of 5v5 small sided games. Competitions (n=7) involved official A-League matches during the 2009–10 season. Player movement characteristics, core temperature (gastrointestinal), skin temperature, nude mass, heart rate, capillary blood (glucose, K+, Na+, haematocrit), perceptual exertion and thermal stress measures were recorded. No significant differences (P>0.05) were present between conditions for any measure of physical performance, although moderate-large effects for a greater total and relative distance covered during training were present (d > 0.8). While mean skin temperature was reduced following cooling, core temperature was only lower until following the warm-up in training and was even less evident during matches (P>0.05; d < 0.6). However, a smaller change in mass (sweat loss) and reduced perceptual exertion and thermal stress were evident during training following cooling (d > 0.9), although again, to a much lesser extent in matches (d = 0.6). In conclusion, equivocal findings were present for the effects of pre-cooling for professional football players during competitive training and matches in the heat. However, performance and thermoregulatory response trends showed similarities to previous laboratory evidence. The field-based nature of the current study may highlight that the transfer of lab findings to field settings is difficult or the strength of the intervention is diminished by the settings.  相似文献   

8.
9.
Abstract

The purpose of this study was to determine how weight training affected the physical fitness of football, basketball, and track and field squads when it was used as a supplement to normal training during different halves of the season. In each sport the athletes were divided into two matched groups: one did weight training during the first half of the season only, and the other group during the second half only. In general, the resulting statistics show that weight training adds significantly to the physical fitness produced by normal training.  相似文献   

10.
ABSTRACT

There is a strong relationship between low physical activity level and cardiovascular diseases (CVD). The popularity of football may be used to promote physical activity and previous evidence has shown it is effective to decrease the risk of CVD. However, the energy expenditure (EE) of recreational football is not well known but it is crucial to develop preventive health programmes.

Fifteen sedentary middle-aged male participants were involved (mean ± SDs; age 43.9 ± 3.1 years, weight 83.0 ± 13.6 kg, height 174.9 ± 6.8 cm). EE was estimated from the heart rate (HR)-VO2 relation during 1-h 5-a-side matches (futsal). Participants covered 3412 ± 381 m in 52 ± 2 min, at an average HR of 85 ± 2% of maximum HR. Estimated EE during a recreational futsal match was 634 ± 92 kcal. One futsal recreational match corresponds to about 50% of American College of Sport Medicine recommended physical activity quantity per week. Based on this estimation: once, twice and 3 sessions per week are equivalent to 50% (634 kcal), 100% (1268 kcal) and 150% (1902 kcal), respectively, of EE suggested in international guidelines. This EE estimation may have important implications for designing recreational football training protocols in health programmes and dose response studies.  相似文献   

11.
Abstract

The relationship between organ weight and swimming capacity was determined in 42 male albino rats. Upon completion of a 4-week training program, the animals were forced to swim to exhaustion with 2 percent of the body weight attached. They were sacrificed and specific gravity and organ weights determined. The results warrant the following conclusions: A significant (p < .05) but low correlation exists between the relative weight of the spleen and lungs with swimming performance. The correlation of relative heart weight and swimming performance approached statistical significance (p < .06). Attaching a weight proportional to the body weight to increase the energy cost of swimming penalizes the heavier animals. Correcting for the inverse relationship between body weight and swim time does not alter appreciably the relationships between organ weights and swim time.  相似文献   

12.
Roy Hay 《国际体育史杂志》2018,35(2-3):196-215
Abstract

Two family stories shed some light on changes in the character and causes of corruption in football in the twentieth and twenty-first centuries. My grandfather was a central figure in an alleged match-fixing episode in Association football in Scotland in the third decade of the twentieth century, while I was a peripheral figure in one in Australia in the last. I came across another one while researching the story of the Croatian soccer clubs in Victoria in the post-Second World War years. I also observed very closely an attempt to fix a series of matches by introducing a number of players into a team on behalf of overseas betting interests in the twenty-first century. Reflecting on these cases is a way of trying to understand how the forms and the drivers of match-fixing have changed in the twenty-first century. The three earlier episodes seem very old fashioned in the context of globalization, the commodification of sport, international gambling syndicates, and systematic corruption at the heart of the world game.  相似文献   

13.
Abstract

Forty-four subjects were given an all-out run test on a motor driven treadmill. The times for attaining heart rates of 150, 160, 170, 180 beats per minute were recorded along with measurements of ventilation, oxygen uptake and carbon dioxide production. The correlations between heart rate times and the all-out run times increased with the heart rate, a correlation of .85 calculated at the rate of 180 beats per minute. Using criteria established by Balke, it was demonstrated that the 180 heart rate serves as a valid cut-off point in measuring circulorespiratory capacity under variable exercise stress conditions.  相似文献   

14.
Abstract

To determine the energy cost of low impact aerobic dance while varying arm movement height and the use of hand weights, 10 adults volunteered to participate in four choreographed trials. All trials consisted of identical leg movements. Arm movements, however, were performed above shoulder level both with and without 0.9-kg hand weights and below shoulder level both with and without 0.9-kg hand weights. Open circuit spirometry was employed throughout the 10-min videotape guided trials, and heart rate was measured by telemetry. Neither the use of hand weights nor the change in arm position height significantly altered the energy cost of low impact aerobic dance. However, heart rate responses were significantly different. Caution should be observed by aerobics instructors and participants as to the use of heart rate as an indicator of intensity for low impact aerobic dance.  相似文献   

15.
Abstract

So far, academic contributions have widely framed football in Africa as a means for migration from a western point of view. At a time, they presented particular and one-dimensional understandings of transnational links in the realm of football migration between Africa and Europe. Macro-level perspectives which mostly focus on African exploitation and dependency and more recently those that take the players’ agency into account reproduce a Eurocentric view of the phenomenon, while disregarding its local perceptions in African settings. Thus, despite the recent shift from a macro- to a micro-level perspective there is still an analytical gap between the ambitions and experiences of migrating players and economic power relations at play on the one hand and the socio-cultural embedding of the transnational connections in football migration on the other. In order to understand why and how football mobilities are indeed linked to ‘the transnational’ in migration there is a need to localize the phenomenon and investigate how local understandings of migration and mobility are lived and expressed in a transnational sport like football. By taking data from fieldwork among West African football migrants, the paper thus shows the local embedding of transnational football migration practices in the West African context.  相似文献   

16.
Abstract

Today, science has become indispensable in professional (association) football. As applying science in football promises a greater sporting success, football training is based on scientific knowledge. Hence, the use of science in football is taken for granted and seems to be commonplace. However, scientific knowledge was hardly employed in football until the early 1950s. In fact, its use needed legitimacy. By taking the German Democratic Republic (GDR) as an example, this study traces the legitimization of science in football in the 1950s and 1960s. The results suggest that the future promise of science as well as the Soviet Union and Soviet football played a substantial role in the scientification of GDR football.  相似文献   

17.
Chengwei Yang 《国际体育史杂志》2017,34(17-18):1933-1949
Abstract

As China has issued a range of policies to elevate football development to a national strategy, school football has been gaining the attention of the public and scholars. This study reviews the implementation of school football policies for the purpose of facilitating development of school football. By combining methodologies such as a literature review, interview survey, and questionnaires with theories of public policy implementation, an analysis framework was set up under which deviations from the school football policies during the implementation process were analyzed comprehensively. It was found that symbolic, selective, and additional implementation and collusions are common when the policies are implemented. Action is needed to strengthen policy promotion and precisely define the goals. Improved mechanisms are needed to manage the policy implementers, differentiating functions of school football. More resources are needed to facilitate policy implementation, which should be allocated in a reasonable manner. Enhanced supervision and appraisal of school football policies is needed, and accountability for their implementation must be clarified.  相似文献   

18.
The health benefits of playing football and the importance of exercise and social contact for healthy ageing are well established, but few older adults in the UK take enough exercise. Football is popular, flexible in format and draws players into engrossing, effortful and social exercise, but the physical demands of play at full speed may make it unsustainable for some older adults. Restricted to walking pace, will play still be engaging? Will health benefits be retained? Will physical demands remain manageable? This pilot study aims to investigate: (1) the experience of older adults playing walking football every week, is it sustainable and rewarding, (2) the intensity and locomotor pattern of walking football, (3) the scale and nature of walking football health benefits and (4) possible cognitive benefits of playing walking football through measures of processing speed, selective and divided attention and updating and inhibition components of executive function. ‘Walking football’ and ‘waiting list’ groups were compared before and after 12 weeks of one-hour per week football. Walking football was found to be engaging, sustainable for older adults and moderately intensive; however, selective health and cognitive benefits were not found from this brief intervention.

Highlights

  • Walking football is a lower impact but authentic form of football that enables older players to extend their active participation.

  • Walking football is enjoyable and moderately demanding and may be a sustainable form of exercise for older adults.

  • Health and cognitive benefits to playing walking football were not found.

  相似文献   

19.
Yiyong Liang 《国际体育史杂志》2017,34(17-18):1835-1853
Abstract

This article examines the concept of corporate governance, in particular the stakeholder context to analysis the relationship between football clubs in China and their local supporter groups for the purpose of gaining insight of its transitional football industry. This mainly qualitative interview-based study focuses upon the process of football marketization in China, with particular emphasis upon the research question: How has marketization impacted the relationship between supporters and football clubs? Along with an examination of the country’s wider social background, cultural influences to illustrate the impact of football marketization on the development pattern of the Chinese game and the specific characteristics of China’s fan culture under its so called socialist market economy.  相似文献   

20.
Abstract

This paper explores multiple and complex relationships between football (soccer), politics, and the economy in postcolonial Zambia. Based on archival and oral sources collected in Zambia, the paper argues that President Frederick Chiluba’s government failed to support football development when it came into power in 1991 because it was elected on a platform of liberalizing the collapsing national economy. Chiluba privatized state-owned companies that were sponsoring the game resulting in the plummeting of the local standards and migration of talented footballers abroad in search of better livelihoods. Furthermore, the paper argues that while the exodus of talented footballers led to the deterioration of the standards of the local league, their transnational experience boosted the performance of the Zambia national football team. This led to the emergence of one of the best national teams the country has ever had. Unfortunately, this particular team perished in the Gabon air disaster in 1993 following the government’s disinvestment in the game. However, a few months after the disaster, the country managed to rebuild a national football team, which emerged as runners up to Nigeria in the 1994 African Cup of Nations final as a result of a large pool of local and foreign-based football players.  相似文献   

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