The impact of physical exercise on calcium balance in healthy subjects during prolonged hypokinesia

Abstract Objective To determine whether during hypokinesia (diminished movement) periodic physical exercise affects calcium (Ca2+ ) balance and Ca2+ loss. Methods Studies were conducted on 30 physically healthy male volunteers during the preexperimental period of 30 days and the experimental period of 364 days. They were equally divided into three groups: active control subjects (ACS), hypokinetic subjects (HKS), and periodic training subjects (PTS). The ACS group ran an average distance of 9.3 ± 1.2 km/d; the HKS group walked an average distance of 1.3 ± 0.2 km/d; and PTS group walked and ran average distances of 1.3 ± 0.2 km/d and 9.2 ± 1.2 km/d for 5 and 2 days per week, respectively. Results Serum Ca2+ level, fecal and urine Ca2+ loss, and Ca2+ imbalance increased ( P < 0.05) in the PTS and HKS groups compared with their preexperimental levels and the values in their respective ACS group. The serum Ca2+ concentration, urine and fecal Ca2+ loss, and Ca2+ imbalance increased more ( P < 0.05) in the PTS group than in the HKS group. Conclusion During hypokinesia, Ca2+ imbalance is more evident with than without physical exercise and Ca2+ loss is exacerbated more with higher than lower Ca2+ imbalance.