Kelly Donahue '12

Correlation of Vitamin D Status with Performance in Female Cross Country Runners - a Follow-up Study

Vitamin D deficiency is more common among athletes than previously recognized, especially during winter months, and in geriatric subjects vitamin D deficiency is correlated with a decrease in muscle strength.

Purpose: to determine if two weeks of vitamin D supplementation of 2000 IU/day in mid-January restores serum vitamin D levels in female cross country athletes to optimal levels [> 75nmol/L] and whether the increase in vitamin D affects aerobic and anaerobic performance.

Methods: IRB approval and informed consent were obtained. Eighteen women were randomly assigned to vitamin D (treatment, 2000 IU) or thiamin (control) for fifteen days; eleven participants completed the study. Blood collections and anaerobic and aerobic tests were conducted before and after 15 days of supplementation. ELISA kit (ALPCO) was used to measure vitaminD3 25(OH) levels. Participants completed a 3k time trail indoors to assess aerobic performance and a 20 meter sprint and an anaerobic treadmill test to assess anaerobic performance.

Results: data were analyzed by repeated measures of analysis of variance. Vitamin D levels between the groups were not statistically different. No significant differences were obtained for any of the performance measures (sprint test, anaerobic treadmill test, and 3k time trial) between the treatment and control groups.

Conclusion: our previous vitamin D study with the team influenced participants because ~47% were taking vitamin D supplements prior to this study. Consequently, the initial vitamin D levels were higher during January than previously observed (total mean 85.8 ± 49.4 nmol/L). Participants on average started and finished this study with optimal serum levels; vitamin D supplementation under these conditions did not have any measureable effects on performance.

To view Poster, click on link below:
Correlation of Vitamin D Status with Performance in Female Cross Country Runners - a Follow-up Study

Research Advisors: Amy Olson, PhD, RDN, LD and Manuel Campos, PhD, Biology