Vitamin D Status and Bone Mineral Density in Female Collegiate Dancers and Cheerleaders: 2670 Board #193 June 3, 9: 30 AM - 11: 00 AM.

Bone mineral density reflects an athlete’s cumulative history of energy availability, physical activity, and menstrual status, as well as nutritional and environmental factors. Although sports with high-impact loading are associated with higher bone mineral density than low-impact or non-impact sports, confounding variables are differences in the athletes’ body size and sport-specific training. The purpose of this study was to determine if bone mineral density (BMD) and vitamin D status are different between two groups of female collegiate athletes who have comparable body size/weight requirements, but who engage in qualitatively different training regimens. Full body, spine and dual femur BMD was assessed by dual energy X-ray absorptiometry (DXA) in members of a university pep-dance team (n = 10) or cheer team (n = 9), ages 18-22. Plasma vitamin D status was assessed by ELIZA. There was no significant difference between the groups for total body BMD (1.23 g/cm dance vs 1.22 g/cm cheer, P = 0.70), spine BMD (1.39 g/cm dance vs 1.36 g/cm cheer, P = 0.72) or dual femur BMD (1.20 g/cm dance vs 1.11 g/cm, P = 0.23). Insufficient serum vitamin D status (20-32 ng/mL) was found in 74% of the athletes (27 ± 4 ng/mL, dance and 25 ± 8 ng/mL, cheer). In addition, estimated daily vitamin D and calcium intakes were less than the RDA for both dancers and cheerleaders. Despite nutritional insufficiencies, BMD was not significantly different between the low-impact activity pep dance team and high-impact activity cheer team, suggesting that the type of physical activity was not as important for BMD in these athletes as participating in 20+ hours a week of physical activity, which could have counteracted the negative effects of the nutrient insufficiencies on their bone health.