Faculty of Nutrition and Food Sciences, University of Porto, Porto, Portugal.
Int J Sport Nutr Exerc Metab. 2011 Jun;21(3):214-21. doi: 10.1123/ijsnem.21.3.214.
Twelve adolescent athletes underwent, in a crossover-design study, 3 separate 90-min training sessions in the following conditions: no fluid ingestion allowed (NF), ad libitum ingestion of water (W), and ad libitum ingestion of a commercial 8% carbohydrate-electrolyte sports beverage (CSB). After each session athletes performed a set of basketball drills (2-point, 3-point, and free-throw shootout, suicide sprints, and defensive zigzags). Body weight (before and after sessions), rating of perceived exertion (RPE), urine color, and beverage acceptability were determined in each session. Athletes also completed a survey about their knowledge and behaviors regarding hydration and fluid replacement. The percentage of weight loss was significantly higher in NF (2.46% ± 0.87%) than in the other 2 conditions (W, 1.08% ± 0.67%, p = .006; CSB, 0.65% ± 0.62%, p = .001) but also higher in W than CSB (p = .012). RPE was higher in NF (16.8 ± 1.96) than in the W (14.2 ± 1.99, p = .004) and CSB (13.3 ± 2.06, p = .002) trials. Athletes' fluid intake was positively correlated with proper self-reported behaviors (r = .75, p = .005) and knowledge (r = .76, p = .004) about fluid and hydration. In conclusion, fluid restriction during exercise was associated with a greater level of dehydration and increased perceived exertion but had no impact on basketball performance compared with ad libitum drinking of water or a CSB. Athletes with more knowledge about hydration and better self-reported hydration behaviors ingested more fluids during training sessions.
在一项交叉设计研究中,12 名青少年运动员在以下三种不同条件下分别进行了 3 次 90 分钟的训练:不允许摄入液体(NF)、自由摄入水(W)和自由摄入一种商业 8%碳水化合物电解质运动饮料(CSB)。每次训练后,运动员都会进行一组篮球训练(2 分、3 分和罚球决胜、自杀冲刺和防守之字形)。在每次训练中,运动员都会测量体重(训练前后)、感知用力程度(RPE)、尿液颜色和饮料接受度。运动员还完成了一份关于他们对水合作用和液体补充的知识和行为的调查问卷。与其他两种条件(W,1.08%±0.67%,p=0.006;CSB,0.65%±0.62%,p=0.001)相比,NF 组的体重减轻百分比明显更高(2.46%±0.87%),但与 CSB 组相比,W 组的体重减轻百分比也更高(p=0.012)。与 W 组(14.2±1.99,p=0.004)和 CSB 组(13.3±2.06,p=0.002)相比,NF 组的 RPE 更高(16.8±1.96)。运动员的液体摄入量与适当的自我报告行为(r=0.75,p=0.005)和关于液体和水合作用的知识(r=0.76,p=0.004)呈正相关。总之,与自由饮水或饮用 CSB 相比,运动中限制液体摄入会导致更高程度的脱水和更高的感知用力程度,但对篮球表现没有影响。对水合作用和水合作用知识了解更多、自我报告水合作用行为更好的运动员,在训练期间会摄入更多的液体。