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Eric Small, Oded Bar-Or, Edgar Van Mil and Saroj Saigal

This study compared the anaerobic performance and the muscle strength between extremely low birthweight (> 1,000 g = ELBW) 11- to 17-year-old adolescents and normal birthweight (< 2,500 g = NEW) controls. Seventeen ELBW (9 females and 8 males) and 17 NEW (9 females and 8 males) subjects took part. ELBW had lower anaerobic performance, as manifested in mean (p = .03) and peak (p < .001) mechanical power per kg body mass (Wingate Anaerobic Test). In absolute units mean power and peak power tended (p = .06 and .08, respectively) to be lower in the ELBW group, but there were no inter-group differences in the isokinetic strength of knee extensors or flexors (Kin Com dynamometer). ANOVA revealed no interaction between the effects of low birthweight and gender. We propose that dynamic, but not static, muscle performance in ELBW is still somewhat inferior in adolescence. This may reflect deficient neuromuscular control.

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David W. Hill, Robert P. Steward Jr. and Cindy J. Lane

The purpose of this study was to evaluate use of the critical power concept with swimmers ages 8 to 18 years. Critical velocity (CV) and anaerobic swimming capacity (ASC) were determined from the results of three short time trials (n = 86) or competition swims (n = 60). Data fit the critical power model well, as evidenced by high R2 and low SEE of CV and ASC estimates. CV was correlated with velocity in an endurance swim (r ≥ 0.86) and ASC was correlated with peak lactate (r ≥ 0.69). Thus, even in very young swimmers, CV and ASC provide mode-specific indices of endurance and anaerobic capacity, respectively.

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David Criswell, Scott Powers, John Lawler, John Tew, Stephen Dodd, Yryik Iryiboz, Richard Tulley and Keith Wheeler

This study compared the efficacy of a 7% glucose polymer beverage containing electrolytes (GP) versus a nonnutrient, nonelectrolyte placebo (P) in maintaining blood homeostasis during recovery from football and determined whether consumption of the GP beverage improved anaerobic performance immediately after football competition when compared with the placebo. Forty-four high school football players participated in a 50-play scrimmage designed to simulate game conditions. At each of six periods before and during the scrimmage, players consumed 170 ml of the GP or P beverage. Eight maximal-effort 40-yd sprints (40-sec rest intervals) were performed before and after the scrimmage to assess the decrement in anaerobic performance from the scrimmage. Venous blood samples were drawn before and after the scrimmage and analyzed. The pre- to postscrimmage differences in mean and peak sprint velocities did not differ between treatments, nor did body weight and plasma. In contrast, the percent decrease in plasma volume was significantly greater in the P group. Postscrimmage increases in glucose and insulin were greater in the GP group. These data suggest that CHO-electrolyte drinks do not prevent a decline in anaerobic performance when compared to water, but a CMO-electrolyte drink is more effective in maintaining PV than water during recovery from anaerobic exercise.

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Richard B. Kreider, Dawn Hill, Greg Horton, Michael Downes, Sarah Smith and Beth Anders

The purpose of this study was to determine the effects of carbohydrate supplementation during intense training on dietary patterns, psychological status, and markers of anaerobic and aerobic performance. Seven members of the U.S. National Field Hockey Team were matched to 7 team counterparts (N = 14). One group was blindly administered a carbohydrate drink containing 1 g·kg−1 of carbohydrate four times daily, while the remaining group blindly ingested a flavored placebo during 7 days of intense training. Subjects underwent pre- and posttraining aerobic and anaerobic assessments, recorded daily diet intake, and were administered the Profile of Mood States (POMS) psychological inventory prior to and following each practice. Results revealed that the carbohydrate-supplemented group had a greater (p < .05) total energy intake, carbohydrate intake, and change (pre vs. post) in time to maximal exhaustion following training while reporting less postpractice psychological fatigue. However, no significant differences were observed in remaining psychological, physiological, or performance-related variables.

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James A. Padfield, Patricia A. Eisenman, Maurie J. Luetkemeier and Sally S. Fitt

A physiological profile of 40 early adolescent female dancers was completed to investigate the characteristics of dancers this age and the possible physical fitness benefits of high levels of dance training. Of those physical fitness variables studied, the only significant difference between performing (high level) and recreational (low level) dancers was the degree of hip flexibility (p<.01). Both groups exhibited lean body density (combined mean of 1.069 g ml−1) as well as moderate aerobic (combined mean of 45.8 ml kg−1 min−1) and anaerobic power (combined mean of 6.5 Watt kg−1). These data suggest that early adolescent dance training encourages a certain level of physical fitness, but higher levels or duration of dance training do not result in or demand exceptional aerobic or anaerobic power.

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James N. Roemmich and John P. Frappier

This study compared successful (n=19) and less successful (n=19) varsity wrestlers matched for age, weight, height, and wrestling experience on physiological variables important for wrestling success using field tests available to a high school wrestling coach. Significant (P<0.05) differences in favor of the successful wrestlers were found for mean left and right grip strength, flexibility of the low back and hamstrings, completed sit-ups, pull-ups, and push-ups. Successful wrestlers also covered a greater distance during a 12min run test and had significantly greater relative anaerobic power (Margaria step test). The groups did not differ significantly in the sum-of-six skinfolds. In conclusion, successful wrestlers had significantly more muscular strength, muscular endurance, flexibility of the low back and hamstrings, aerobic fitness, and relative anaerobic power than less successful wrestlers. It is suggested less successful wrestlers engage in regular training sessions that include stretching, cardiovascular, and strength/power components.

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Dominic Micklewright, Murray Griffin, Valerie Gladwell and Ralph Beneke

A within subjects experimental design (N = 16) was used where participants performed a 30-s Wingate anaerobic cycling test (WAnT) after 30-min rest and after 30-min back massage. Mood State was measured before and after each intervention and after the WAnTs. No significant change in mood was detected following rest or massage. However, WAnT performance was better following massage compared to rest. Mood disturbance increased following the WAnT in both the rest and massage conditions. The results suggest that preperformance massage had no effect on mood state yet seemed to facilitate enhanced WAnT performance. The relationship between massage and anaerobic performance remains unclear, however is almost certainly mediated by preperformance psychological factors other than mood state.

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Martin Buchheit, Roberto Solano and Grégoire Paul Millet

The aim of the present investigation was to compare the accuracy of the heart-rate (HR) deflection point (HRDP) and the second HR variability threshold (HRVTh2) to predict anaerobic threshold in boys. HRDP was determined from slope trends of successive linear regressions. HRVTh2 was determined from the high frequency’s peak and power-density trends. The second ventilatory threshold (VTh2) corresponding to the first decrease in PETCO2, with an increase in VE/VCO2, was used as the reference measure of AnT. Results show that VO2 and HR were similar at HRDP, HRVTh2, and VTh2. HRVTh2 and HRDP were highly correlated. It appears that HRVTh2 is a good alternative to HRDP for assessing anaerobic threshold. HRVTh2 and HRDP might rely on similar mechanisms.

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Jelle de Jong, Linda van der Meijden, Simone Hamby, Samantha Suckow, Christopher Dodge, Jos J. de Koning and Carl Foster

Purpose:

To reach top performance in cycling, optimizing distribution of energy resources is crucial. The purpose of this study was to investigate power output during 250-m, 500-m, and 1000-m cycling time trials and the characteristics of the adopted pacing strategy.

Methods:

Nine trained cyclists completed an incremental test and 3 time trials that they were instructed to finish as quickly as possible. Preceding the trials, peak power during short sprints (PPsprint) and gross efficiency (GE) were measured. During the trials, power output and oxygen consumption were measured to calculate the contribution of the aerobic and anaerobic energy sources. After the trial GE was measured again.

Results:

Peak power during all trials (PPTT) was lower than PPsprint. In the 250-m trial the PPTT was higher in the 1000-m trial (P = .008). The subjects performed a significantly longer time at high intensity in the 250-m than in the 1000-m (P = .029). GE declined significantly during all trials (P < .01). Total anaerobically attributable work was less in the 250-m than in the 500-m (P = .015) and 1000-m (P < .01) trials.

Conclusion:

The overall pacing pattern in the 250-m trial appears to follow an all-out strategy, although peak power is still lower than the potential maximal power output. This suggests that a true all-out pattern of power output may not be used in fixed-distance events. The 500-m and 1000-m had a more conservative pacing pattern and anaerobic power output reached a constant magnitude.

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Craig A. Horswill

Amateur wrestlers practice weight loss for ergogenic reasons. The effects of rapid weight loss on aerobic performance are adverse and profound, but the effects on anaerobic performance are equivocal Anaerobic performance—strength and power—may be the most relevant type of performance to the wrestler. Maintenance of or even small decrements in anaerobic performance may translate into improvements in performance relative to the weight class, the factor by which wrestlers are matched for competition. During the recovery period between the official weigh-in and competition, wrestlers achieve at least partial nutritional recovery, which appears to benefit performance. Successive bouts of (a) weight loss to make weight and (b) recovery for performance lead to weight cycling. There is speculation that weight cycling may contribute to chronic glycogen depletion, reductions in fat-free weight, a decrease in resting metabolic rate, and an increase in body fat. The latter two would augment the difficulty of losing weight for subsequent weigh-ins. Most research indicates that the suppressed resting metabolic rate with weight loss in wrestlers appears to be transient, but subsequent research is needed for confirmation.