Resistance training to boost vitamin D?

Vitamin D has many significant physiological functions in the body, most notably in boosting calcium and strengthening bone metabolism. We retain vitamin D by soaking up the sun, or through many of the foods that we eat, including fish oils, egg yolks, cheese, milk and yoghurt. While these may seem straightforward and accessible ways of absorbing vitamin D, many people are still vitamin D deficient, which can lead to significant health problems.

Vitamin D deficiency can cause the muscles to weaken and consequently increase the risk of recurrent falls and fractures, particularly in the elderly. Along with ensuring that we spend time outside in the sunshine, and consume plenty of vitamin D-rich foods, a new study has found that increasing the amount of resistance exercise we do can also increase the number of vitamin D receptors in our muscles, hence improving vitamin D metabolism.

Vitamin D supplementation has previously been associated with increasing the number of vitamin D receptors in the body, hence improving muscle mass and function in people with vitamin D deficiency. Rather than focusing on supplementation, this new research has sought to demonstrate that regular bouts of resistance exercise, rather than aerobic exercise, can increase the intramuscular expression of vitamin D receptors.

Explaining the importance of this finding, Doctor Satoshi Fujita, from Ritsumeikan University in Japan, said it proves an effective way to improve vitamin D metabolism without supplementation. Fujita also noted that the mechanisms of exercise-induced increased vitamin D receptors might be different to the ones induced by vitamin supplements.

Source: Experimental Physiology