Children's Exercise and Nutrition Centre, McMaster University, Hamilton, ON L8N 3Z5, Canada.
Appl Physiol Nutr Metab. 2010 Dec;35(6):834-41. doi: 10.1139/H10-084.
We determined whether beverage flavoring and composition would stimulate voluntary drink intake, prevent dehydration, and maintain exercise performance in heat-acclimated adolescent males running in the heat. Eight adolescent (age, 13.7 ± 1.1 years) runners (peak oxygen uptake, 59.5 ± 4.0 mL·kg-1·min-1) underwent at least four 80-min exercise heat-acclimation sessions before completing 3 experimental sessions. All sessions were performed at 30 °C and 60%-65% relative humidity. Each experimental session consisted of five 15-min treadmill runs at a speed eliciting 65% peak oxygen uptake, with a 5 min rest prior to each run. Ten minutes after the final run, a time to exhaustion test was performed at a speed eliciting 90% peak oxygen uptake. Counterbalanced experimental sessions were identical, except for fluid intake, which consisted of tap water (W), flavored water (FW), and FW with 6% carbohydrate and 18 mmol·L-1 NaCl (CNa) consumed ad libitum. Fluid intake and body weight were monitored to calculate dehydration. Voluntary fluid intake was similar to fluid losses in W (1032 ± 130 vs. 1340 ± 246 g), FW (1086 ± 86 vs. 1451 ± 253 g), and CNa (1259 ± 119 vs. 1358 ± 234 g). As a result, significant dehydration was avoided in all trials (-0.45% ± 0.68% body weight in W, -0.66% ± 0.50% body weight in FW, and -0.13% ± 0.71% body weight in CNa). Core temperature increased by ~1 °C during exercise, but was not different between trials. Time to exhaustion was not different between trials and averaged 8.8 ± 1.7 min. Under exercise conditions more closely reflecting real-life situations, heat-acclimatized adolescent male runners can appropriately gauge fluid intake regardless of the type of beverage made available, resulting in consistency in exercise performance.
我们旨在探究饮料的口味和成分是否能刺激自愿性液体摄入，预防脱水，并维持热适应青少年男性在热环境中的运动表现。8 名青少年（年龄，13.7±1.1 岁）跑步者（峰值摄氧量，59.5±4.0mL·kg-1·min-1）在完成 3 次实验前，至少进行了 4 次 80 分钟的运动热适应训练。所有的实验都在 30°C 和 60%-65%的相对湿度下进行。每个实验都由 5 个 15 分钟的跑步机跑步组成，速度达到 65%的峰值摄氧量，每个跑步前休息 5 分钟。最后一次跑步后 10 分钟，进行 90%峰值摄氧量的力竭测试。平衡的实验内容除了液体摄入外，其余都相同，液体摄入分别为自来水（W）、调味水（FW）和含 6%碳水化合物和 18mmol·L-1 NaCl（CNa）的 FW 随意摄入。监测液体摄入和体重以计算脱水情况。W（1032±130 克比 1340±246 克）、FW（1086±86 克比 1451±253 克）和 CNa（1259±119 克比 1358±234 克）中，W、FW 和 CNa 的液体摄入与液体损失相似。因此，在所有试验中都避免了显著的脱水（W 中脱水-0.45%±0.68%体重，FW 中脱水-0.66%±0.50%体重，CNa 中脱水-0.13%±0.71%体重）。运动过程中核心体温升高约 1°C，但各试验之间没有差异。力竭时间在各试验中没有差异，平均为 8.8±1.7 分钟。在更接近现实生活情况的运动条件下，热适应的青少年男性跑步者可以根据提供的饮料类型适当评估液体摄入，从而保持运动表现的一致性。
