Does oral creatine supplementation enhance exercise performance of female Judo athletes?

本研究的主要目的是阐明口服肌酸补充剂对间歇最大运动和等速大腿力量以及女性柔道运动员表现的影响。此外，我们还研究了运动对身体成分和能量代谢的影响。在这里，我们描述了间歇性最大运动时的表现，等速大腿力量，以及限制空间的身体成分。方法：以6名女柔道运动员为研究对象。年龄为19.67±0.82（±SD）岁。补充摄入方法及测量周期：第一次测量后，受试者连续6天服用安慰剂（6 g葡萄糖，每天4次），第二天进行第二次测量。随后，受试者连续6天摄入肌酸（5 g一水肌酸+ 1 g葡萄糖，每天4次），第二天进行第三次测量。更多：受试者重复五组（每组20秒）10秒的极限骑行。等速大腿力量：我们测量了在0（等速）、60、180、300度/秒的角速度下的膝关节伸展和屈曲扭矩。身体成分：我们用水密度测定法测量身体成分。采用氧再呼吸法测定肺残气量。结果和讨论先前的研究报道，补充肌酸可以增强间歇性高强度运动的表现。然而，在本研究中，在1次试验中，所有的峰值功率、平均功率和功，它们的下降率（从第1次试验到第5次试验）和总功在补充肌酸后没有改善。在180度/秒和300度/秒时，第三次测量的膝关节延伸扭矩高于第一次和第二次测量（P < 0.05）。体重和体脂率从第一次测量到第三次测量均有所增加（P < 0.05），但无脂重没有变化。我们得出结论，口服肌酸补充剂可以提高中高角速度下的膝关节伸展强度，但对女性柔道运动员间歇性极限运动和无脂体重的表现没有影响。少

IntroductionThe main purpose of this study is to clarify the effects of oral creatine supplementation on performance during intermittent maximal exercise and isokinetic thigh strength and of female judo athletes. In addition, we examined the effects on body composition and energy metabolism during exercise. Here, we described the performance during intermittent maximal exercise, the isokinetic thigh strength, and the body composition for the restriction of space.MethodsSubjects : Six female Judo athletes participated in this study. Their ages were 19.67 ± 0.82 (±SD) years.Supplement intake method and measurement period : After first measurements, the subjects ingested placebo (6 g glucose, 4 times per a day) for six days, and received second measurements in the next day. Afterwards, the subjects ingested the creatine (5 g creatine monohydrate + 1 g glucose, 4 times per a day) for six days, and received third measurements in the next day.Performance during intermittent maximal exercise … More : The subjects repeated five bouts (20-s intervals) of 10-s maximal cycling.Isokinetic thigh strength : We measured knee extension and flexion torque at each angle velocity of 0 (isometric), 60, 180, 300 degree/s.Body composition : We used hydrodensitometry to measure the body composition. Oxygen rebreathing method was used to measure lung residual volume.Results and discussionPrevious studies reported that the creatine supplementation strengthened the performance during intermittent intense exercise. However, in this study, all of peak power, average power, and work during 1 trial, their decreasing rate (from 1st to 5th trial), and total work did not improved after creatine supplementation. The knee e extension torque at the 180 and 300 degree/s were higher (P < 0.05) in the third measurements compared with the first measurements and the second measurements. Body weight and percent body fat increased (P < 0.05) from the first measurements to the third measurements, but fat free weight unchanged.We conclude that oral creatine supplementation improves knee extension strength at middle and high angle velocities though it doesn't influence performance during intermittent maximal exercise and fat free weight in female Judo athletes. Less