Background/Aims: Zinc is involved in numerous metabolic roles, including energy metabolism, immunity and antioxidative effects. Zinc losses during exercise, in particular through sweat, are well documented. However, conflicting results have been reported for changes in circulating and tissue zinc concentrations following exercise. The present review aims to quantify the acute effects of aerobic exercise on markers of zinc status in humans.
Methods: We conducted a systematic review of peer-reviewed papers published up to December 2014 to identify studies that investigated the acute effects of exercise on indices of zinc status. Meta-analyses were conducted to determine changes in serum zinc concentration following exercise.
Results: Forty-five studies were included in the systematic review. Sufficient data were available from 34 studies (46 comparisons) to quantify the change in serum zinc following exercise. Serum zinc concentration was significantly higher immediately following exercise (0.45 ± 0.12 μmol/L, P<0.001; mean ± SE). Secondary analyses showed greater increase in serum zinc for untrained individuals (0.65 ± 0.19 μmol/L, P=0.001) and exercise sessions that involved running (0.71 ± 0.26 μmol/L, P=0.006) or maximal intensity (0.77 ± 0.20 μmol/L, P<0.001). During exercise recovery, serum zinc concentration was lower than pre-exercise values (-1.31 ± 0.22 μmol/L, P<0.001).
Conclusions: This meta-analysis indicated significant changes in serum zinc concentration following aerobic exercise, suggesting acute perturbations in zinc homeostasis. Further research is required to ascertain the long-term effects of exercise on zinc metabolism and potential consequences for dietary zinc requirement for physically active populations.
Funding Source: N/A