Effects of Vitamin D Supplementation on Strength, Bone Density, and Injury Risk in Collegiate Athletes

Vitamin D is a hormone that is important for bone and muscle health. As such, not having
enough vitamin D in your body is associated with increased risk of injury and reduced health
and athletic performance. It is often recommended that individuals who have low levels of
vitamin D take vitamin D supplements. However, the effects of vitamin D supplementation on
health and strength gains in collegiate athletes are not known. The goal of this study is to
determine whether vitamin D supplementation increases strength and bone density, while
reducing the risk of injury in collegiate athletes. Fasting vitamin D concentrations will be
measured and athletes will be supplemented daily with Vitamin D for 8-12 weeks. The amount of
supplementation will depend on whether the athlete is categorized as sufficient (>30ng/ml),
insufficient (20-35ng/ml), or deficient (<20ng/ml). Vitamin D concentrations, strength, bone
density, and injury risk will be assessed before and after the intervention period.

Inclusion Criteria:

- athlete for a sanctioned Virginia Tech sport

Exclusion Criteria:

- pregnant or trying to become pregnant, currently taking vitamin D (>600IU/day),
calcium (>1000mg/dl), taking any performance enhancing supplements (example,
creatine), or any other medication or nutritional supplements that might influence the
study variables, cardiac or thyroid problems, have diabetes, or epilepsy