School of Science and Technology, Nottingham Trent University, Nottinghamshire, UK.
J Athl Train. 2012 Jan-Feb;47(1):61-6. doi: 10.4085/1062-6050-47.1.61.
Many active people finish exercise hypohydrated, so effective rehydration after exercise is an important consideration.
To determine the effects of a rehydration solution containing whey protein isolate on fluid balance after exercise-induced dehydration.
Randomized controlled clinical trial.
University research laboratory.
Twelve healthy men (age = 21 ± 1 years, height = 1.82 ± 0.08 m, mass = 82.71 ± 10.31 kg) participated.
INTERVENTION(S): Participants reduced body mass by 1.86% ± 0.07% after intermittent exercise in the heat and rehydrated with a volume of drink in liters equivalent to 1.5 times their body mass loss in kilograms of a solution of either 65 g/L carbohydrate (trial C) or 50 g/L carbohydrate and 15 g/L whey protein isolate (trial CPl. Solutions were matched for energy density and electrolyte content. Urine samples were collected before and after exercise and for 4 hours after rehydration.
MAIN OUTCOME MEASURE(S): We measured urine volume, drink retention, net fluid balance, urine osmolality, and subjective responses. Drink retention was calculated as the difference between the volume of drink ingested and urine produced. Net fluid balance was calculated from fluid gained through drink ingestion and fluid lost through sweat and urine production.
Total cumulative urine output after rehydration was not different between trial C (1173 ± 481 mL) and trial CP (1180 ± 330 mL) (F(1) = 0.002, P = .96), and drink retention during the study also was not different between trial C (50% ± 18%) and trial CP (49% ± 13%) (t(11) = -0.159, P =.88). At the end of the study, net fluid balance was negative compared with baseline for trial C (-432 ± 436 mL) (t(11) = 3.433, P = .03) and trial CP (-432 ± 302 mL) (t(11) = 4.958, P = .003).
When matched for energy density and electrolyte content, a solution of carbohydrate and whey protein isolate neither increased nor decreased rehydration compared with a solution of carbohydrate.
许多活跃的人在运动后会出现脱水，因此有效的运动后补水是一个重要的考虑因素。
确定含有乳清蛋白分离物的补液对运动诱导脱水后液体平衡的影响。
随机对照临床试验。
大学研究实验室。
12 名健康男性（年龄=21±1 岁，身高=1.82±0.08 m，体重=82.71±10.31 kg）参与了研究。
参与者在热环境中进行间歇性运动，体重减轻 1.86%±0.07%，然后通过摄入相当于其体重损失 1.5 倍的液体量来补充水分，其中试验 C 组摄入的是 65 g/L 碳水化合物的溶液，试验 CP 组摄入的是 50 g/L 碳水化合物和 15 g/L 乳清蛋白分离物的溶液。两种溶液的能量密度和电解质含量相匹配。在运动前后和补液后 4 小时收集尿液样本。
我们测量了尿液量、饮料保留量、净液体平衡、尿液渗透压和主观反应。饮料保留量是通过摄入的饮料量与产生的尿液量之间的差异来计算的。净液体平衡是通过摄入的饮料和通过汗液和尿液产生的液体损失来计算的。
补液后总的累积尿液排出量在试验 C（1173±481 mL）和试验 CP（1180±330 mL）之间没有差异（F(1)=0.002，P=.96），并且在研究过程中饮料保留量在试验 C（50%±18%）和试验 CP（49%±13%）之间也没有差异（t(11)=-0.159，P=.88）。在研究结束时，与基线相比，试验 C（-432±436 mL）（t(11)=3.433，P=.03）和试验 CP（-432±302 mL）（t(11)=4.958，P=.003）的净液体平衡为负值。
当能量密度和电解质含量相匹配时，含有碳水化合物和乳清蛋白分离物的溶液与含有碳水化合物的溶液相比，既不会增加也不会减少补液。
