Exercise: A Possibly Effective Way to Improve Vitamin D Nutritional Status

Vitamin D deficiency has become a widespread public health problem owing to its potential adverse health effects. Generally, the nutritional status of vitamin D depends on sunlight exposure and dietary or supplementary intake. However, recent studies have found that exercise can influence circulating 25(OH)D levels; although, the results have been inconclusive. In this review, we focused on the effect of exercise on circulating vitamin D metabolites and their possible mechanisms. We found that endurance exercise can significantly increase serum 25(OH)D levels in vitamin D-deficient people but has no significant effect on vitamin D-sufficient people. This benefit has not been observed with resistance training. Only chronic endurance exercise training can significantly increase serum 1,25(OH)(2)D, and the effect may be sex-dependent. Exercise may influence 25(OH)D levels in the circulation by regulating either the vitamin D metabolites stored in tissues or the utilization by target tissues. The effects of exercise on 25(OH)D levels in the circulation may be dependent on many factors, such as the vitamin D nutritional status, exercise type and intensity, and sex. Therefore, further research on the effects and mechanisms of exercise on vitamin D metabolites is required.

Automated summary

Exercise can affect the levels of vitamin D metabolites in circulation. Endurance exercise can increase serum 25(OH)D levels, but has limited effect on serum 1,25(OH)(2)D levels. Exercise may influence 25(OH)D levels in the circulation by regulating the storage of vitamin D metabolites in tissues or their utilization by target tissues. The effects of exercise on 25(OH)D levels may be dependent on factors such as vitamin D nutritional status, exercise type and intensity, and sex. Further research is needed to investigate the effects and mechanisms of exercise on vitamin D metabolites.