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Robert J. Gregor and Marilyn Pink

As part of an ongoing project to evaluate elite track and field throwers in the United States, the javelin competition was filmed during the 1983 Pepsi Invitational Track Meet. A high-speed video camera (Spin Physics SP2000) was positioned orthogonal to the javelin runway to record the release of all throws. During this competition, Tom Petranoff’s world record (99.72 m) was filmed at 200 fields per second. Subsequent frame-by-frame digitization yielded results consistent with reports in the literature. Release velocity was 32.3 m/s and represents one of the highest values ever reported. Angle of release was .57r, javelin attitude at release was .64r» and angle of attack was .07r. While optimum values for these release parameters, in light of published results, remain open to discussion, the results presented here represent unique information on a world record performance and can serve as a basis of comparison for future performances.

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Matt Brearley, Ian Norton, David Kingsbury and Simon Maas

Introduction:

Anecdotal reports suggest that elite road motorcyclists suffer from high core body temperatures and physiological and perceptual strain when competing in hot conditions.

Methods:

Four male non-heat-acclimatized elite motorcyclists (3 Superbike, 1 Supersport) had their gastrointestinal temperature, heart rate, and respiratory rate measured and recorded throughout practice, qualifying, and race sessions of an Australian Superbike and Supersport Championship round contested in tropical conditions. Physiological strain was calculated during the sessions, and fluid-balance measures were taken during practice and qualifying. Rider thermal sensation was assessed immediately postsession.

Results:

Mean ambient temperature and relative humidity were 29.5–30.2°C and 64.5–68.7%, respectively, across the sessions. Gastrointestinal temperature rose from 37.6°C to 37.7°C presession at a median rate of 0.035°C, 0.037°C ,and 0.067°C/min during practice, qualifying, and race sessions to reach medians of 38.9°C, 38.8°C, and 39.1°C postsession, respectively. The peak postsession gastrointestinal temperature was 39.8°C. Median heart rates were ~164, 160, and 177 beats/min during the respective practice, qualifying, and race sessions, contributing to median physiological strain of 5.5, 5.6, and 6.2 across the sessions. Sweat rates were 1.01 and 0.90 L/h during practice and qualifying sessions, while rider thermal sensation was very hot after each session.

Conclusions:

This investigation confirms that elite road motorcyclists endure moderate to high physiological strain during practice, qualifying, and race sessions, exhibiting more-rapid rates of body-heat storage, higher core body temperatures, and higher physiological and perceptual strain than their stock-car-racing counterparts when competing in tropical conditions.

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John Kenny, SarahJane Cullen and Giles D. Warrington

Purpose:

“Ice-mile” swimming presents significant physiological challenges and potential safety issues, but few data are available. This study examined deep body temperature (BT), respiratory rate (RR), and swim performance in 2 swimmers completing an ice-mile swim of 1 mile (1600 m) in water less than 5°C.

Methods:

Two male cold-water-habituated swimmers completed a 1-mile lake swim in 3.9°C water. For comparative purposes, they completed an indoor 1-mile swim in 28.1°C water. The Equivital physiological monitoring system was used to record BT and RR before, during, and after each swim. Total time to complete the swims and 400-m splits were recorded.

Results:

One swimmer became hypothermic after 27 min while swimming, reaching BT of 33.7°C at swim’s end. On exiting the water the swimmers experienced large BT after-drops of –3.6°C and –2.4°C, reaching low points of 33.2°C and 31.3°C 38 and 23 min postswim, respectively. Respiratory rate and swim pace decreased over the course of the ice-mile swim for both swimmers. Swim pace for 1 swimmer declined sharply in the final 400-m lap of the ice mile when he was hypothermic. Both swimmers remained hypothermic 60 min postswim (34.2°C and 33.4°C).

Conclusion:

Ice-mile swimmers may become hypothermic while swimming, and the postswim BT after drop may expose them to dangerous levels of hypothermia. Pace and RR should be monitored as proxies for a swimmer’s physiological state. Postswim recovery should also be monitored for hypothermia for at least 1 h.

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Pedro Figueiredo, Renata Willig, Francisco Alves, João Paulo Vilas-Boas and Ricardo J. Fernandes

Purpose:

To examine the effect of swimming speed (v) on the biomechanical and physiological responses of a trained front-crawl swimmer with a unilateral arm amputation.

Methods:

A 13-y-old girl with a unilateral arm amputation (level of the elbow) was tested for stroke length (SL, horizontal displacement cover with each stroke cycle), stroke frequency (SF, inverse of the time to complete each stroke cycle), adapted index of coordination (IdCadapt, lag time between propulsive phases), intracycle velocity variation (IVV, coefficient of variation of the instantaneous velocity–time data), active drag (D, hydrodynamic resistance), and energy cost (C, ratio of metabolic power to speed) during trials of increasing v.

Results:

Swimmer data showed a positive relationship between v and SF (R 2 = 1, P < .001), IVV (R 2 = .98, P = .002), D (R 2 = .98, P < .001), and C (R 2 = .95, P = .001) and a negative relationship with the SL (R 2 = .99, P = .001). No relation was found between v and IdCadapt (R 2 = .35, P = .22). A quadratic regression best fitted the relationship between v and general kinematical parameters (SL and SF); a cubic relationship fit the IVV best. The relationship between v and D was best expressed by a power regression, and the linear regression fit the C and IdCadapt best.

Conclusions:

The subject’s adaptation to increased v was different from able-bodied swimmers, mainly on interarm coordination, maintaining the lag time between propulsive phases, which influence the magnitude of the other parameters. These results might be useful to develop specific training and enhance swimming performance in swimmers with amputations.

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Chad S.G. Witcher, Nicholas L. Holt, John C. Spence and Sandra O’Brien Cousins

The purpose of this study was to assess rural older adults’ perceptions of leisure-time physical activity and examine these perceptions from a historical perspective. Semistructured interviews were conducted with 10 inhabitants (mean age 82 years) of Fogo Island, Newfoundland and Labrador, Canada. Interviews were transcribed verbatim and subjected to inductive analysis. Member-checking interviews were conducted with 5 participants. Findings indicated that beginning in childhood, participants were socialized into a subculture of work activity. As a result of these historical and social forces, leisure-time physical activity did not form part of the participants’ lives after retirement. Strategies for successful aging involved keeping busy, but this “busyness” did not include leisure-time physical activity. Results demonstrated the importance of developing a broader understanding of how past and present-day contexts can influence participation in leisure-time physical activity.

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Mike Sleap, Barbara Elliott, Martha Paisi and Helen Reed

Background:

There are concerns about the future health of young people due to inactive lifestyles. However, evidence about their physical activity levels is not extensive, especially with regard to affluent young people. This study aimed to investigate whether young people from affluent backgrounds met public health recommendations for physical activity.

Methods:

Diary accounts of lifestyle activity were collected from 219 students ages 9 to 15 y attending a fee-paying school in England.

Results:

Pupils spent an average of 121 min per day participating in physical activities of at least moderate intensity, considerably more than public health recommendations of 60 min per day. However, almost a quarter of these young people engaged in less than 60 min of physical activity per day of at least moderate intensity.

Conclusions:

The picture to emerge was one of a balance between sedentary pursuits like television and homework and physical activities such as sport and active play.

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Virginie de Bressy de Guast, Jim Golby, Anna Van Wersch and Fabienne d’Arripe-Longueville

This study presents a complete psychological skills training (PST) program with a wheelchair athlete and examines the program effectiveness using a mixed-method approach. After initial testing, the athlete followed a two-month program of self-confidence building, motivational, visualization/relaxation, and injury management techniques. Quantitative and qualitative methods were used to examine the impacts on performance and psychological abilities. The triangulated results suggest that the PST program was perceived as effective by the athlete in terms of his sporting performances and mental skills. The characteristics and implications of a PST program with this wheelchair athlete are discussed, as well as the study limitations and the perspectives for future research.

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Motohide Miyahara and Alena Wafer

The teaching process and outcome in a skill theme program and a movement concepts program were described and analyzed in seven children with developmental coordination disorder. It was hypothesized that the skill theme program would improve targeted skills and perceived physical competence, whereas the movement concepts program would improve self-esteem and creativity. The seven children were taught individually by the same student teachers twice a week for a period of five weeks in one of the teaching methods. After a vacation, the teachers changed their teaching strategies and taught the same children using the alternative method. Although the hypothesis was generally supported, the children’s response to and progress in the programs varied. Possible factors influencing the variation were discussed.

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Aditi Mankad, Sandy Gordon and Karen Wallman

The present study features a psycholinguistic analysis, using Pennebaker’s (1989) emotional disclosure paradigm, of an athlete’s experience in recovering from injury. “GL,” a male athlete rehabilitating from anterior cruciate ligament reconstruction, participated in a 9-week testing protocol. A 3-day intervention was used, consisting of three 20-minute writing sessions, which promoted disclosure of negative emotions associated with injury and rehabilitation. In addition, measures of stress, mood disturbance, and self-esteem were administered from pre- to postintervention and at follow-up. Results revealed decreases in stress and mood disturbance, as well as an increase in self-esteem. Analysis of writing samples revealed increased use of linguistic markers indicating affective awareness. Findings also highlighted the importance of emotional disclosure and cognitive integration in reducing stress and enhancing understanding of injury.

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Gabriel Brizuela Costa, Miguel Polo Rubio, Salvador Llana Belloch and Pedro Pérez Soriano

This study, with a top T-52 class athlete, determines the relationship between stroke frequency (SF) and push time (PT) and wheelchair velocity (Wv) using different handrim diameters (HD) and the effect of different HDs on the athlete’s heart rate (HR) and blood lactate (LACT) at competition speeds. Wv shows a linear-direct relationship with SF but a linear-inverse relationship with PT (p < .001 in both cases). Using bigger handrims (0.37 m instead of 0.36 m), SF increases 6%, while PT decreases 27% (at 24 Km·h–1). HR (p < .0001) increases with Wv and is also affected by HD with differences between the 0.34 m—0.36 m handrim group (lower values) and the 0.37 m handrim (higher values). Significant interaction (p < .0001) is identified between HD and Wv. LACT results seem to follow the same direction as HR. This methodology helped the athlete to choose the optimum HD, and his achievements (some world records) indicate that HD optimization could be highly profitable in sport terms.