Vitamin D has been in the news a lot over the last year. Once thought to simply aid in calcium absorption, recent research has shown the sunshine vitamin does far more for our health than we once thought. A new research review published in the journal Physical Activity and Nutrition found that among other benefits, having healthy vitamin D levels was positively correlated with endurance performance.
The benefits of vitamin D
The researchers performed a systematic review on studies about vitamin D in athletes that assessed serum vitamin D levels, vitamin D and physical performance, vitamin D and musculoskeletal injuries and practical guidelines for supplementation of vitamin D. Several of the studies determined that a high proportion of athletes were deficient in the vitamin, and that low levels had negative effects on muscle strength, power and endurance. Athletes with low levels of vitamin D also appear to be at a greater risk for stress fractures and other musculoskeletal injuries and experience higher rates of inflammation after high-intensity exercise.
On the other hand, studies show that healthy levels of vitamin D are positively correlated with endurance performance and muscle strength. Several of the reviewed studies also associated increased levels of vitamin D with a lower rate of injuries and an overall improved performance in sports. All of this data caused the authors of the review to conclude:
“Vitamin D deficiency must be treated by correcting the lifestyle to restore normal blood vitamin D levels, which is fundamental in maintaining or restoring the physical performance and musculoskeletal health of athletes.”
Recommendations to runners
According to the researchers, athletes should have serum levels of vitamin D of at least 32 ng/mL, but 40 ng/ml would be preferable. They recommend all athletes have their vitamin D levels tested because the effort required to restore vitamin D levels to normal may vary depending on your current status. “Generally, regular and safe exposure to sunlight and/or foods and supplements rich in vitamin D are
recommended,” they said.
How to get more vitamin D
Vitamin D is synthesized in the skin and produced in the body following 15-20 minutes of direct exposure to the sun. You can also absorb it through protein-rich foods, like egg yolk, fish and dairy products. Getting enough vitamin D can be difficult in Canada due to our short summers and long winters, so many dietitians and doctors recommend both athletes and non-athletes take a supplement to support their needs. If you’re concerned about your vitamin D status, talk to your doctor about getting it tested, so they can provide safe recommendations for supplementation.