Baty Jacob J, Hwang Hyonson, Ding Zhenping, Bernard Jeffrey R, Wang Bei, Kwon Bongan, Ivy John L
Exercise Physiology and Metabolism Laboratory, Department of Kinesiology and Health Education, University of Texas, Austin, Texas 78712, USA.
J Strength Cond Res. 2007 May;21(2):321-9. doi: 10.1519/R-21706.1.
The purpose of this study was to determine whether resistance exercise performance and postexercise muscle damage were altered when consuming a carbohydrate and protein beverage (CHO-PRO; 6.2% and 1.5% concentrations). Thirty-four male subjects (age: 21.5 +/- 1.7 years; height: 177.3 +/- 1.1 cm; weight: 77.2 +/- 2.2 kg) completed 3 sets of 8 repetitions at their 8 repetition maximum to volitional fatigue. The exercise order consisted of the high pull, leg curl, standing overhead press, leg extension, lat pull-down, leg press, and bench press. In a double-blind, posttest-only control group design, subjects consumed 355 ml of either CHO-PRO or placebo (electrolyte and artificial sweetener beverage) 30 minutes prior to exercise, 177 ml immediately prior to exercise, 177 ml halfway through the exercise bout, and 355 ml immediately following the exercise bout. There were no significant differences between groups relative to exercise performance. Cortisol was significantly elevated in the placebo group compared to the CHO-PRO group at 24 hours postexercise. Insulin was significantly elevated immediately pre-exercise, after the fourth lift, immediately postexercise, 1 hour, and 6 hours postexercise in CHO-PRO compared to the placebo group. Myoglobin levels in the placebo group approached significance halfway through the exercise bout and at 1 hour postexercise (p = 0.06 and 0.07, respectively) and were significantly elevated at 6 hours postexercise compared to the CHO-PRO group. Creatine kinase levels were significantly elevated in the placebo group at 24 hours postexercise compared to the CHO-PRO group. The CHO-PRO supplement did not improve performance during a resistance exercise bout, but appeared to reduce muscle damage, as evidenced by the responses of both myoglobin and creatine kinase. These results suggest the use of a CHO-PRO supplement during resistance training to reduce muscle damage and soreness.
本研究的目的是确定饮用碳水化合物和蛋白质饮料（CHO-PRO；浓度分别为6.2%和1.5%）时，抗阻运动表现和运动后肌肉损伤是否会发生改变。34名男性受试者（年龄：21.5±1.7岁；身高：177.3±1.1厘米；体重：77.2±2.2千克）以8次重复最大值完成3组每组8次重复的训练，直至自愿疲劳。运动顺序包括高翻、腿弯举、站姿推举、腿伸展、下拉、腿推举和卧推。在双盲、仅后测的对照组设计中，受试者在运动前30分钟饮用355毫升CHO-PRO或安慰剂（电解质和人工甜味剂饮料），运动前即刻饮用177毫升，运动过程中半程饮用177毫升，运动后即刻饮用355毫升。两组在运动表现方面无显著差异。与CHO-PRO组相比，安慰剂组在运动后24小时时皮质醇显著升高。与安慰剂组相比，CHO-PRO组在运动前即刻、第四次举重后、运动后即刻、运动后1小时和6小时时胰岛素显著升高。安慰剂组的肌红蛋白水平在运动过程中半程和运动后1小时接近显著水平（分别为p=0.06和0.07），与CHO-PRO组相比，在运动后6小时显著升高。与CHO-PRO组相比，安慰剂组在运动后24小时时肌酸激酶水平显著升高。CHO-PRO补充剂在抗阻运动期间并未改善运动表现，但似乎减少了肌肉损伤，肌红蛋白和肌酸激酶的反应证明了这一点。这些结果表明，在抗阻训练期间使用CHO-PRO补充剂可减少肌肉损伤和酸痛。
