J Orthop Sports Phys Ther. 1989;10(11):451-5. doi: 10.2519/jospt.1989.10.11.451.
This study investigated the effect of dehydration on measurements of body composition by hydrostatic weighing (HW) and bioelectric impedance analysis (BIA). Ten endurance-trained male athletes between the ages of 18 and 42 years performed an endurance training session consisting of running until body weight was reduced by approximately 3%. Body composition was determined prior to exercise and immediately after exercise by HW and BIA techniques. A high correlation existed between pre- and postdehydration for both HW and BIA. Validity coefficients between HW and BIA were moderate (predehydration 0.85 and postdehydration 0.82). In addition, BIA percent fat was 3.5% higher than HW percent fat. The BIA revealed a mean loss of 2.1% fat BIA and only 0.9% fat HW after approximately 45 minutes of exercise. BIA also showed an increase in percent body water (mean = 2.6%) in all 10 subjects after dehydration. There are indications that BIA, with its present equational configuration, is measuring something other than lean body weight. J Orthop Sports Phys Ther 1989;10(11):451-455.
本研究旨在探讨在运用静水称重法（HW）和生物电阻抗分析法（BIA）测量身体成分时，脱水对其产生的影响。10 名年龄在 18 至 42 岁之间的耐力型男运动员进行了一次耐力训练，直到他们的体重减轻了大约 3%。在运动前和运动后，运动员分别采用 HW 和 BIA 技术来测定身体成分。HW 和 BIA 在脱水前后均具有高度相关性。HW 和 BIA 的有效性系数适中（脱水前为 0.85，脱水后为 0.82）。此外，BIA 测定的体脂百分比比 HW 高 3.5%。在大约 45 分钟的运动后，BIA 显示出平均 2.1%的体脂 BIA 损失，而 HW 仅损失了 0.9%的体脂。BIA 还显示出所有 10 名受试者的身体水分百分比增加（平均为 2.6%）。有迹象表明，BIA 目前的方程配置所测量的内容并非瘦体重。《矫形与运动物理治疗杂志》1989 年 10 月；10（11）：451-455。
