Muscle potassium and potassium losses during hypokinesia in healthy subjects

Hypokinesia (HK) induces electrolyte losses in electrolyte-deficient tissue, yet the mechanisms of electrolyte losses in electrolyte-deficient tissue remain unknown. Mechanisms of electrolyte deposition could be involved. To determine the effect of prolonged HK on potassium (K+) deposition were measured muscle K+ content and K+ losses. Studies were conducted on 20 physically healthy male volunteers during 30 days pre-experimental period and 364 days experimental period. Subjects were equally divided into two groups: control subjects (CS) and experimental subjects (ES). The CS group was run average distances of 9.8±1.7 km day(-1) and the ES group was walked average distances of 2.7±0.6 km day(-1). Muscle K+ content decreased (p<0.05) and plasma K+ concentration, and K+ losses in urine and feces increased (p<0.05) in the ES group compared to their pre-experimental level and the values in their respective CS group. Muscle K+ content, plasma K+ level, and urine and fecal K+ losses did not show any changes in the CS group compared to their pre-experimental values. The conclusion was that K+ losses in K+-deficient muscle of healthy subjects could have been attributable to the less efficient K+ deposition inherently to prolonged HK.