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David B. Pyne and Rick L. Sharp

The aquatic sports competitions held during the summer Olympic Games include diving, open-water swimming, pool swimming, synchronized swimming, and water polo. Elite-level performance in each of these sports requires rigorous training and practice to develop the appropriate physiological, biomechanical, artistic, and strategic capabilities specific to each sport. Consequently, the daily training plans of these athletes are quite varied both between and within the sports. Common to all aquatic athletes, however, is that daily training and preparation consumes several hours and involves frequent periods of high-intensity exertion. Nutritional support for this high-level training is a critical element of the preparation of these athletes to ensure the energy and nutrient demands of the training and competition are met. In this article, we introduce the fundamental physical requirements of these sports and specifically explore the energetics of human locomotion in water. Subsequent articles in this issue explore the specific nutritional requirements of each aquatic sport. We hope that such exploration will provide a foundation for future investigation of the roles of optimal nutrition in optimizing performance in the aquatic sports.

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Noam Eyal, Michael Bar-Eli, Gershon Tenenbaum and Joan S. Pie

The aim of this study was to examine whether outcome expectations can be generalized from one defined task to other tasks. A deception paradigm was employed in which outcome expectations were manipulated. High, low, or medium expectations toward performing five tasks, which gradually increased in complexity and shared a common skill, were manipulated. Ninety adult males were randomly assigned to manipulation groups. A within-subjects repeated measures ANOVA indicated that those manipulated by medium expectations showed elevated perceptions of outcome expectations. Their performance, however, was superior only in the two tasks most similar in complexity to the initial task. On the less similar tasks, the differences among the groups were insignificant. A generalization effect can therefore be demonstrated on outcome expectations and performance to a certain degree of task complexity. Implications of the superior performance of participants manipulated to produce medium outcome expectations are discussed.

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Gretchen E. Iversen

Research on the psychosocial aspects of maturational timing has not addressed the experience of the late-developing gymnast. Studies to date have used conceptual and timing frameworks incommensurate with the experience of the athlete who reaches puberty in late adolescence. The role of environmental influences, including the support group, in a gymnast’s experience of puberty is salient. In order for sports practitioners to help late maturing female gymnasts deal with their personal and physical development, a reconceptualization of the related psychosocial parameters is needed.

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Sergei V. Kolmogorov, Olga A. Rumyantseva, Brian J. Gordon and Jane M. Cappaert

The purpose of this study was to describe the hydrodynamic characteristics of the four strokes by gender and performance level. Active drag during maximal swimming was measured in each of the four swimming strokes (freestyle, butterfly, backstroke, and breaststroke) on males and females of varying ability levels using the perturbation method developed by Kolmogorov and Duplisheva (1992). Active drag (FDa), the hydrodynamic coefficient (Cx Da), and total external mechanical power output (Pto) were calculated at each swimmer's maximal swimming velocity. There were complex, nonlinear relationships between maximum swimming velocity and the three hydrodynamic indicators. The four swimming strokes were ranked in order of resistance based on the three hydrodynamic indicators. The order, from least to most resistance, was (1) freestyle, (2) backstroke, butterfly, (3) breaststroke. No statistical difference was seen between the backstroke and butterfly. Within each stroke, the most important factor for reducing active drag appeared to be individual biomechanical technique.

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Andrea J. Braakhuis, Will G. Hopkins and Timothy E. Lowe

The beneficial effects of exercise and a healthy diet are well documented in the general population but poorly understood in elite athletes. Previous research in subelite athletes suggests that regular training and an antioxidant-rich diet enhance antioxidant defenses but not performance.

Purpose:

To investigate whether habitual diet and/or exercise (training status or performance) affect antioxidant status in elite athletes.

Methods:

Antioxidant blood biomarkers were assessed before and after a 30-min ergometer time trial in 28 male and 34 female rowers. The antioxidant blood biomarkers included ascorbic acid, uric acid, total antioxidant capacity (TAC), erythrocyte- superoxide dismutase, glutathione peroxidase (GPx), and catalase. Rowers completed a 7-d food diary and an antioxidant-intake questionnaire. Effects of diet, training, and performance on resting biomarkers were assessed with Pearson correlations, and their effect on exercise-induced changes in blood biomarkers was assessed by a method of standardization.

Results:

With the exception of GPx, there were small to moderate increases with exercise for all markers. Blood resting TAC had a small correlation with total antioxidant intake (correlation .29; 90% confidence limits, ±.27), and the exercise-induced change in TAC had a trivial to small association with dietary antioxidant intake from vitamin C (standardized effect .19; ±.22), vegetables (.20; ±.23), and vitamin A (.25; ±.27). Most other dietary intakes had trivial associations with antioxidant biomarkers. Years of training had a small inverse correlation with TAC (−.32; ±.19) and a small association with the exercise-induced change in TAC (.27; ±.24).

Conclusion:

Training status correlates more strongly with antioxidant status than diet does.

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Lee Nolan, Benjamin L. Patritti, Laura Stana and Sean M. Tweedy

The purpose of this study was to evaluate the extent to which residual shank length affects long jump performance of elite athletes with a unilateral transtibial amputation. Sixteen elite, male, long jumpers with a transtibial amputation were videoed while competing in major championships (World Championships 1998, 2002 and Paralympic Games, 2004). The approach, take-off, and landing of each athlete’s best jump was digitized to determine residual and intact shank lengths, jump distance, and horizontal and vertical velocity of center of mass at touchdown. Residual shank length ranged from 15 cm to 38 cm. There were weak, nonsignificant relationships between residual shank length and (a) distance jumped (r = 0.30), (b) horizontal velocity (r = 0.31), and vertical velocity (r = 0.05). Based on these results, residual shank length is not an important determinant of long jump performance, and it is therefore appropriate that all long jumpers with transtibial amputation compete in the same class. The relationship between residual shank length and key performance variables was stronger among athletes that jumped off their prosthetic leg (N = 5), and although this result must be interpreted cautiously, it indicates the need for further research.

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Mohamad S. Motevalli, Vincent J. Dalbo, Reza S. Attarzadeh, Amir Rashidlamir, Patrick S. Tucker and Aaron T. Scanlan

Purpose:

To evaluate anthropometric measures and serum markers of myostatin-pathway activity after different weight-reduction protocols in wrestlers.

Methods:

Subjects were randomly assigned to a gradual-weight-reduction (GWR) or rapid-weight-reduction (RWR) group. Food logs were collected for the duration of the study. Anthropometric measurements and serum samples were collected after an 8-h fast at baseline and after the weight-reduction intervention. Subjects reduced body mass by 4%. The GWR group restricted calories over 12 d, while the RWR group restricted calories over 2 d. A series of 2 × 5 repeated-measures (RM) ANOVAs was conducted to examine differences in nutrient consumption, while separate 2 × 2 RM ANOVAs were conducted to examine differences in anthropometric measures and serum markers. When applicable, Tukey post hoc comparisons were conducted. Significance for all tests was set at P < .05.

Results:

There were no between-groups differences for any anthropometric measure (P > .05). Subjects in both groups experienced a significant reduction in body mass, fat mass, lean mass, and percent body fat (P < .05). There were no between-groups differences in serum markers of myostatin-pathway activity (P > .05), but subjects in the RWR condition experienced a significant increase in serum myostatin (P < .01), a decrease in follistatin (P < .01), and an increase in myostatin-to-follistatin ratio (P < .001).

Conclusion:

Although there were no between-groups differences for any outcome variables, the serum myostatin-to-follistatin ratio was significantly increased in the RWR group, possibly signaling the early stages of skeletal-muscle catabolism.

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Burke D. Grandjean, Patricia A. Taylor and Jay Weiner

During the women’s all-around gymnastics final at the 2000 Olympics, the vault was inadvertently set 5 cm too low for a random half of the 36 gymnasts. The error was widely viewed as undermining their confidence and adversely affecting their subsequent performance. This paper examines whether the vault problem had such a carryover effect. Both pretest scores (from preliminary rounds) and posttest scores (from the final) are available on vault, bars, beam. and floor. Manipulation checks establish that the error had experimental impact on vault performance. However, from comparing means, from analysis of covariance, from multiple regression, and from statistically adjusting the official scores, it is clear that the vault error had little if any effect on later performances or on the final standings. Elite athletes in a closed-skill sport apparently learn to concentrate so well that most can recover from a mishap and refocus successfully for the next effort.