Armstrong L E, Epstein Y
Human Performance Laboratory, Department of Physiology and Neurobiology, University of Connecticut, U-110, 2095 Hillside Rd, Storrs, CT, 06269-1110, USA.
Int J Sport Nutr. 1999 Mar;9(1):1-12. doi: 10.1123/ijsn.9.1.1.
Body water and electrolyte balance are essential to optimal physiological function and health. During exercise, work, or high temperatures, a significant level of dehydration can develop, and the ratio of extracellular to intracellular fluid can change, despite an ample supply of water. Physical and cognitive performance are impaired at 1-2% dehydration, and the body can collapse when water loss approaches 7%. Because fluid needs and intakes vary, formulating one general guideline for fluid replacement is difficult. Knowing the amount of water lost in sweat may enable predicting fluid needs via mathematical models for industrial, athletic, and military scenarios. Sodium imbalance might result from excessive Na+ loss or from gross overhydration. In most work or exercise lasting < 3-4 hr, the major concern is that fluid be available to prevent heat-related illnesses, which can be prevented if fluid and electrolyte losses are balanced with intake, using the recommendations presented.
身体水分和电解质平衡对于最佳生理功能和健康至关重要。在运动、工作或高温环境下，尽管有充足的水分供应，仍可能出现显著程度的脱水，细胞外液与细胞内液的比例也可能发生变化。脱水1 - 2%时，身体和认知能力会受损，当失水量接近7%时，身体可能会崩溃。由于液体需求和摄入量各不相同，制定一个通用的补液指南很困难。了解汗液中的失水量或许能够通过工业、运动和军事场景的数学模型来预测液体需求。钠失衡可能是由于钠过度流失或严重水合过度所致。在大多数持续时间小于3 - 4小时的工作或运动中，主要关注点是要有液体来预防与热相关的疾病，如果按照所提供的建议使液体和电解质损失与摄入量保持平衡，这些疾病是可以预防的。
