Effects of high doses of magnesium in drinking water and voluntary wheel running on magnesium and calcium concentrations in rats.

The effect of high magnesium intake in addition to supplementation and voluntary wheel activity on magnesium and calcium homeostasis was investigated in rats. Thirty-six 5-week-old male Wistar rats were divided into four groups (n = 9). Groups 2 and 4 received five hundred ppm of elemental magnesium as MgCl2 provided in drinking water. After 1 week of acclimatization and 4 weeks of supplement and/or exercise, the animals were fasted and sacrificed. It appears that magnesium supplementation as well as exercise played some significant role in the homeostatic changes of magnesium and calcium. This could be of great significance in better understanding of mineral homeostasis particularly in sports medicine.