Magnesium supplements' effect on magnesium balance in athletes during prolonged restriction of muscular activity

Electrolyte supplements may be used to prevent negative electrolyte balance during hypokinesia (HK) (decreased number of kilometres per day). The aim of this study was to evaluate the effect of daily intakes of magnesium (Mg) supplements on Mg balance during prolonged HK. Studies were done during a 30-day period of pre-HK and during a 364-day period of HK. Forty male athletes aged 22-26 years were chosen as subjects. They were equally divided into four groups: unsupplemented ambulatory control (UACS), unsupplemented hypokinetic subjects (UHKS), supplemented hypokinetic subjects (SHKS) and supplemented ambulatory control subjects (SACS). The SHKS and UHKS groups were maintained under an average running distance of 1.7 km/day, while the SACS and UACS groups experienced no changes in their professional training and routine daily activities. The SHKS and SACS groups took daily 23 mg Mg as Mg lactate per kilogram body weight. Mg balance, urinary and faecal Mg excretion and serum Mg concentration, anthropometric characteristics and peak oxygen uptake were measured. Negative Mg balance, faecal and urinary Mg excretion and serum Mg concentration increased significantly (p