Purpose : The purpose of this study was to compare the effect of single administration of a about 100kcal carbohydrate-protein complex (CHO-PRO) supplement versus that of protein (PRO) supplement which included little carbohydrate on recovery after training.
Methods: Seven male subjects participated in this study. They cycled to deplete their muscle glycogen stores.Immediately after training, they received a CHO-PRO or a PRO supplement.
Results : Fatigue visual analogue scale (VAS) scores and Urinary 3-Methylhistidine/Creatinine (3-MH/Cr) excretion of the CHO-PRO treatment were significantly lower than that of the PRO treatment. Although no significant differences were observed between treatments, performance time of the CHO-PRO treatment was long in six of seven subjects.
Conclusions : The results suggested that a low calorie CHO-PRO supplement is more effective for recovery after training than that of PRO supplement.

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The purpose of this study was to investigate the straight sprint and counter-movement jump related to running with changes of direction using correlational analysis and multiple regression analysis. One hundred and seventy-five male collegiate soccer players, who belonged to the team between the seasons in 2005 to 2010, participated in this study. Different changes of direction tests were conducted every two years. Sprint test and counter-movement jump test were conducted throughout all seasons. Each running with changes of direction was statistically correlated with all sprint times and counter-movement jump. Through multi-regression analysis, however, each running with changes of direction was significantly correlated with different sprint time or counter-movement jump each other. Therefore, it was considered that straight sprint and counter-movement jump related to running with changes of direction, while individual physical factors determining to different running with changes of direction performance would be exist.

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This study aimed to describe hip muscle strength and cross-sectional area in male and female junior sprinters. A total of 45 high-school sprinters (SP) of both genders participated in the study. Distance runners (DR, n=11) and untrained subjects (CON, n=18) at similar ages also participated as reference groups. Hip strength was measured at 3.14 and 5.23 rad/s by an isokinetic dynamometer. Muscle cross-sectional area of psoas major (PM) and gluteus maximus (GM) were determined by magnetic resonance imaging. Hip extension strength was more developed in SP compared with DR or CON. PM and GM cross-sectional area corrected by fat-free mass were not different between SP and DR for the female but were significantly larger in SP than DR for the male. No relation was found between either side of hip strength and sprint-performance level. However, higher performance female SP showed significantly larger PM while higher performance male SP showed larger GM. These results indicate that sprinters even at junior ages are noted for having greater hip strength in extension side regardless of gender; however gender-related differences in hip muscularity may exist in junior sprinters.

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The purpose of this study was to clarify the differences of physiological responses induced by exercise in hypoxia, normoxia, and hyperoxia. Eight sprint kayak paddlers performed incremental tests in hypoxia (16.4 %), normoxia (20.9 %), and hyperoxia (30.0 %) on separated days. As a result, power output (6 %, P < 0.05) , oxygen uptake (5 %, P < 0.05) and oxygen saturation were significantly lower at maximal intensity in and hypoxia compared with normoxia. Ventilation volume and blood lactate were significantly higher at some submaximal stages in hypoxia compared with normoxia. In contrast, power output (8 %, P < 0.05) and oxygen uptake (9 %, P < 0.05) were significantly higher at maximal intensity in and blood lactate was significantly lower in hyperoxia compared with normoxia. These results indicate that paddling in hypoxia or hyperoxia may increase physical and physiological load compared to normoxia. It could be said that more various training loads can be imposed by adding training in hypoxia and hyperoxia.

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The present study investigates the relationship of the performance to the pacing strategy, the gear ratio and the pedaling rate, and makes some suggestions for coaching and training track cyclists in the 200m flying time trial (FTT), 250m, 500m,1km and 4km time trial (TT). During the period of Challenge the Olympics in 2010, the races of 117 cyclists were recorded, and pacing strategies, gear ratios and pedaling rates were calculated. The performance during the 200mFTT, 250m, 500m and 1km TT were considerably influenced by the maximal and starting velocity during the races, but not by decreasing velocity. We also found negative relationships between the gear ratio and the performance in the 200m, 500m and 1km TT, and between the decreasing velocity and the performance in the 4km TT. These results suggested that the cyclists should improve their starting and top speed in the 200m, 250m, 500m and 1km TT, whereas they should also improve their ability to maintain high speed in the 4km TT.

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