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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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Gary J. Slater, Anthony J. Rice, David Jenkins, Jason Gulbin and Allan G. Hahn

To strengthen the depth of lightweight rowing talent, we sought to identify experienced heavyweight rowers who possessed physique traits that predisposed them to excellence as a lightweight. Identified athletes (n = 3) were monitored over 16 wk. Variables measured included performance, anthropometric indices, and selected biochemical and metabolic parameters. All athletes decreased their body mass (range 2.0 to 8.0 kg), with muscle mass accounting for a large proportion of this (31.7 to 84.6%). Two athletes were able to maintain their performance despite reductions in body mass. However, performance was compromised for the athlete who experienced the greatest weight loss. In summary, smaller heavyweight rowers can successfully make the transition into the lightweight category, being nationally competitive in their first season as a lightweight.

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Andrew Renfree, Graham J. Mytton, Sabrina Skorski and Alan St Clair Gibson

Purpose:

To identify tactical factors associated with progression from preliminary rounds in middle-distance running events at an international championship.

Methods:

Results from the 2012 Olympic Games were used to access final and intermediate positions, finishing times, and season-best (SB) times for competitors in men’s and women’s 800-m and 1500-m events (fifteen 800-m races and ten 1500-m races). Finishing times were calculated as %SB, and Pearson product–moment correlations were used to assess relationships between intermediate and finishing positions. Probability (P) of qualification to the next round was calculated for athletes in each available intermediate position.

Results:

There were no significant differences in finishing times relative to SB between qualifiers and nonqualifiers. In the 800-m, correlation coefficients between intermediate and final positions were r = .61 and r = .84 at 400 m and 600 m, respectively, whereas in the 1500-m, correlations were r = .35, r = .43, r = .55, and r = .71 at 400 m, 800 m, 1000 m, and 1200 m, respectively. In both events, probability of qualification decreased with position at all intermediate distances. At all points, those already in qualifying positions were more likely to qualify for the next round.

Conclusions:

The data demonstrate that tactical positioning at intermediate points in qualifying rounds of middle-distance races is a strong determinant of qualification. In 800-m races it is important to be in a qualifying position by 400 m. In the 1500-m event, although more changes in position are apparent, position at intermediate distances is still strongly related to successful qualification.

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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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Jamie Stanley, Shaun D’Auria and Martin Buchheit

The authors examined whether changes in heart-rate (HR) variability (HRV) could consistently track adaptation to training and race performance during a 32-wk competitive season. An elite male long-course triathlete recorded resting HR (RHR) each morning, and vagal-related indices of HRV (natural logarithm of the square root of mean squared differences of successive R−R intervals [ln rMSSD] and the ratio of ln rMSSD to R−R interval length [ln rMSSD:RR]) were assessed. Daily training load was quantified using a power meter and wrist-top GPS device. Trends in HRV indices and training load were examined by calculating standardized differences (ES). The following trends in week-to-week changes were consistently observed: (1) When the triathlete was coping with a training block, RHR decreased (ES −0.38 [90% confidence limits −0.05;−0.72]) and ln rMSSD increased (+0.36 [0.71;0.00]). (2) When the triathlete was not coping, RHR increased (+0.65 [1.29;0.00]) and ln rMSSD decreased (−0.60 [0.00;−1.20]). (3) Optimal competition performance was associated with moderate decreases in ln rMSSD (−0.86 [−0.76;−0.95]) and ln rMSSD:RR (−0.90 [−0.60;−1.20]) in the week before competition. (4) Suboptimal competition performance was associated with small decreases in ln rMSSD (−0.25 [−0.76;−0.95]) and trivial changes in ln rMSSD:RR (−0.04 [0.50;−0.57]) in the week before competition. To conclude, in this triathlete, a decrease in RHR concurrent with increased ln rMSSD compared with the previous week consistently appears indicative of positive training adaptation during a training block. A simultaneous reduction in ln rMSSD and ln rMSSD:RR during the final week preceding competition appears consistently indicative of optimal performance.

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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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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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Jessie M. Wall, Janelle L. Kwee, Marvin J. McDonald and Richard A. Bradshaw

This study was the first to explore the treatment effects of observed and experiential integration (OEI) therapy for the salient psychological barriers to performance experienced by athletes. The hermeneutic single case efficacy design was used to explore the relationship between OEI therapy and athlete psychological functioning. The participant was a student-athlete who met the criteria for the performance dysfunction (multilevel classification system of Sport psychology) category, which indicates that subclinical issues were present. After five phases of data collection, a rich case record was compiled and referenced to develop skeptic and affirmative briefs and corresponding rebuttals by two research teams of three experts (OEI clinician, non-OEI clinician, and sport expert). Three independent judges adjudicated the cases and unanimously concluded that the client changed considerably to substantially and that OEI, the therapeutic relationship, and client expectancy were active variables in the change process.

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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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Charles A. Maher

This article reflects a response to the case of a freshman student-athlete lacrosse player who was in the process of transitioning into a Division I environment. Within the context of the case response, guidelines were provided for assessment of the student-athlete at four separate, yet interrelated levels of psychological development. These levels were: as a person; as a student-athlete who exists in a high-risk environment; as a teammate; and as a performer in the sport of lacrosse. Relatedly, it was suggested how the strengths and needs of this individual could be assessed and how resulting needs assessment information could be used in the design of an individual plan for the student-athlete. As such, it was suggested that the individual plan would most likely center on helping the individual to become increasingly aware of herself as a person and performer, to offer guidance in adhering to her physical rehabilitation, and to develop a routine for her daily preparation and for monitoring her practice and game performances. The case response concludes with a description of a framework for determining the student-athlete’s readiness for engaging in the plan and its activities.