Document Type


Date of Degree Completion

Spring 2017

Degree Name

Master of Science (MS)



Committee Chair

Kelly Pritchett

Second Committee Member

Robert Pritchett

Third Committee Member

Elizabeth Broad


Recent studies suggest that a substantial proportion of elite athletes with SCI (spinal cord injury) have insufficient 25(OH)D status which may be associated with decreased muscle strength. This study: 1) examined the effects of a 16-week sliding scale Vitamin D supplementation protocol on 25(OH)D concentration and 2) determined whether subsequent 25(OH)D status impacts muscle performance in elite athletes with SCI. Thirty-four members of the US Olympic Committee Paralympic program, and the Canadian Wheelchair Sports Association from outdoor sports participated. Serum 25(OH)D concentrations, lifestyle and dietary factors were assessed during the Winter and Spring. Participants were assigned a 16-week sliding scale vitamin D3 (cholecalciferol) (KleanAthlete Brand) supplementation protocol based on initial 25(OH)D levels. Participants with deficient 25(OH)D (<50 nmol/L) status received 50,000 IU/wk. for 8 wks., and participants with insufficient status (50-75 nmol/L) received 35,000 IU/week for 4 weeks followed by a maintenance dosage of 15,000 IU/wk. Participants with sufficient status (>75nmol/L) received the maintenance dosage of 15,000 IU/wk. 25 (OH)D concentrations increased significantly after supplementation (p <.001; 66.3 + 24.3 nmol/L; 111.3 + 30.8 nmol/L) for Winter and Spring, respectively. 26% of athletes had sufficient 25(OH)D concentrations prior to supplementation, and 91% had sufficient concentrations post supplementation. 62% of participants improved handgrip strength post supplementation. No change in 20-meter wheelchair sprint performance time was observed. The 16-week sliding scale supplementation protocol used in the current study is effective for achieving sufficient vitamin D concentrations during the winter months in elite athletes with SCI.


Thank you. This would not have been possible with out the love and support from my teachers, family and friends.