Costill D L, Cote R, Fink W J
Am J Clin Nutr. 1982 Aug;36(2):266-75. doi: 10.1093/ajcn/36.2.266.
Eight men were studied during two 4-day exercise-dietary regimens, once under a control diet (80 mEq K+/day) and again with a diet low in K+ (25 mEq/day). Muscle K+ increased 5 to 6% as a result of the two exercise-dietary regimens, while no change was observed for muscle Na+ or Mg++. Plasma volume increased throughout the 4 days of each exercise-diet sequence, with the low K+ regimen resulting in the largest plasma volume gain (+15%) and a marked reduction in urinary K+ excretion. Despite the losses of K+ in sweat and the low K+ intake, there was a relatively small decrease in total body K+ content (less than 2% of body content). Based on these measurements of extracellular (plasma) and tissue (muscle) water and electrolytes, we have concluded that in combination with 4 days of heavy exercise and sweating, a low K+ diet will not significantly diminish the total body K+ content.
八名男性在两种为期4天的运动-饮食方案下接受了研究，一次是在对照饮食（80 mEq K⁺/天）下，另一次是在低钾饮食（25 mEq/天）下。两种运动-饮食方案使肌肉钾含量增加了5%至6%，而肌肉钠或镁含量未观察到变化。在每个运动-饮食阶段的4天中，血浆容量均增加，低钾方案导致血浆容量增加最多（+15%），尿钾排泄显著减少。尽管汗液中流失了钾且钾摄入量低，但全身钾含量相对仅略有下降（不到身体含量的2%）。基于这些细胞外（血浆）和组织（肌肉）水及电解质的测量结果，我们得出结论，结合4天的剧烈运动和出汗，低钾饮食不会显著降低全身钾含量。
