Costill D L, Coté R, Fink W J, Van Handel P
Int J Sports Med. 1981 Aug;2(3):130-4. doi: 10.1055/s-2008-1034598.
In an effort to describe the changes in water and electrolyte contents of active and inactive muscles during prolonged effort, seven healthy men were studied during 120 min of cycling. Needle biopsy samples were taken from the deltoid (inactive) and vastus lateralis (active) muscles before, at 10 and 120 min of exercise, and 30 min after exercise. Water and electrolyte contents of blood and active muscle tissue showed a significant change with the onset of exercise, while the inactive muscle was unaffected. As a consequence of the exercise, the subjects lost an average of 2.40 liters of body water, 93 mEq Na+, 22 mEq K+, 95 mEq Cl-, and 5 mEq Mg++. These water and electrolyte losses were not detectable in the muscle tissue sampled at the end of exercise or after 30 min recovery. Based on the loss of Cl-, body weight and plasma volume, extracellular, intracellular, and total body water volumes were calculated to decrease approximately 9%, 3% and 7.5%, respectively, at the end of the exercise. These observations confirm earlier findings that exercise and electrolyte losses in sweat and urine do not alter the calculated membrane potential of active and inactive muscle.
为了描述长时间运动过程中活跃肌肉和不活跃肌肉的水和电解质含量变化，对7名健康男性进行了120分钟的自行车运动研究。在运动前、运动10分钟和120分钟时以及运动后30分钟，从三角肌（不活跃）和股外侧肌（活跃）采集针吸活检样本。血液和活跃肌肉组织的水和电解质含量在运动开始时出现显著变化，而不活跃肌肉未受影响。运动后，受试者平均流失2.40升身体水分、93毫当量钠、22毫当量钾、95毫当量氯和5毫当量镁离子。在运动结束时或恢复30分钟后采集的肌肉组织中未检测到这些水和电解质的流失。根据氯的流失、体重和血浆量计算，运动结束时细胞外液、细胞内液和总体液量分别减少约9%、3%和7.5%。这些观察结果证实了早期的发现，即运动以及汗液和尿液中的电解质流失不会改变活跃肌肉和不活跃肌肉的计算膜电位。
