The University of Memphis, Cardiorespiratory/Metabolic Laboratory, Department of Health and Sport Sciences, 106 Roane Fieldhouse, Memphis, TN 38152.
J Int Soc Sports Nutr. 2012 Jan 18;9(1):1. doi: 10.1186/1550-2783-9-1.
Sport drinks are ubiquitous within the recreational and competitive fitness and sporting world. Most are manufactured and artificially flavored carbohydrate-electrolyte beverages. Recently, attention has been given to coconut water, a natural alternative to manufactured sport drinks, with initial evidence indicating efficacy with regard to maintaining hydration. We compared coconut water and a carbohydrate-electrolyte sport drink on measures of hydration and physical performance in exercise-trained men.
Following a 60-minute bout of dehydrating treadmill exercise, 12 exercise-trained men (26.6 ± 5.7 yrs) received bottled water (BW), pure coconut water (VitaCoco®: CW), coconut water from concentrate (CWC), or a carbohydrate-electrolyte sport drink (SD) [a fluid amount based on body mass loss during the dehydrating exercise] on four occasions (separated by at least 5 days) in a random order, single blind (subject and not investigators), cross-over design. Hydration status (body mass, fluid retention, plasma osmolality, urine specific gravity) and performance (treadmill time to exhaustion; assessed after rehydration) were determined during the recovery period. Subjective measures of thirst, bloatedness, refreshed, stomach upset, and tiredness were also determined using a 5-point visual analog scale.
Subjects lost approximately 1.7 kg (~2% of body mass) during the dehydrating exercise and regained this amount in a relatively similar manner following consumption of all conditions. No differences were noted between coconut water (CW or CWC) and SD for any measures of fluid retention (p > 0.05). Regarding exercise performance, no significant difference (p > 0.05) was noted between BW (11.9 ± 5.9 min), CW (12.3 ± 5.8 min), CWC (11.9 ± 6.0 min), and SD (12.8 ± 4.9 min). In general, subjects reported feeling more bloated and experienced greater stomach upset with the CW and CWC conditions.
All tested beverages are capable of promoting rehydration and supporting subsequent exercise. Little difference is noted between the four tested conditions with regard to markers of hydration or exercise performance in a sample of young, healthy men. Additional study inclusive of a more demanding dehydration protocol, as well as a time trial test as the measure of exercise performance, may more specifically determine the efficacy of these beverages on enhancing hydration and performance following dehydrating exercise.
运动饮料在娱乐和竞技健身及运动领域无处不在。大多数是人工制造和调味的碳水化合物电解质饮料。最近，人们对椰子水产生了兴趣，椰子水是一种替代人工制造运动饮料的天然选择，初步证据表明其在保持水分方面具有功效。我们比较了椰子水和碳水化合物电解质运动饮料在运动训练男性的水分保持和身体表现方面的效果。
在进行 60 分钟的脱水跑步机运动后，12 名运动训练男性（26.6±5.7 岁）在四种情况下（至少相隔 5 天）以随机、单盲（受试者和研究人员）、交叉设计的方式分别接受瓶装水（BW）、纯椰子水（VitaCoco®：CW）、浓缩椰子水（CWC）或碳水化合物电解质运动饮料（SD）[根据脱水运动期间的体重损失量确定的液体量]。在恢复期间确定了水合状态（体重、液体保留、血浆渗透压、尿比重）和表现（跑步机疲劳时间；在重新水合后评估）。还使用 5 点视觉模拟量表来确定口渴、腹胀、清爽、胃部不适和疲劳等主观感觉。
受试者在脱水运动中损失了约 1.7 公斤（约 2%的体重），在摄入所有条件后以相对相似的方式恢复了这一体重。在液体保留的任何测量指标上，椰子水（CW 或 CWC）和 SD 之间均无差异（p>0.05）。关于运动表现，BW（11.9±5.9 分钟）、CW（12.3±5.8 分钟）、CWC（11.9±6.0 分钟）和 SD（12.8±4.9 分钟）之间没有显著差异（p>0.05）。一般来说，与 CW 和 CWC 条件相比，受试者报告感觉更腹胀，胃部不适更大。
所有测试的饮料都能够促进水合作用并支持随后的运动。在年轻健康男性的样本中，四种测试条件在水合作用和运动表现的标志物方面几乎没有差异。包括更严格的脱水方案以及作为运动表现测量的计时赛测试的进一步研究，可能会更具体地确定这些饮料在脱水运动后增强水合作用和表现的功效。
