The D-BIICEP Study

Athletes and active individuals have been identified as an at-risk group for a low vitamin D status, specifically those residing in countries of higher latitude (such as the United Kingdom). This especially applies to those who train indoors for their sport, this is because Vitamin D is primarily produced following skin exposure to ultraviolet B (UVB) exposure. Vitamin D is essential for the maintenance of optimal bone and musculoskeletal health. It has also been suggested to play a role in the prevention of illness incidence, such as in upper respiratory tract infections (URTI). More recent research has indicated that an improved Vitamin D status may also play a role in enhancing exercise performance. Therefore, having a poor vitamin D status could negatively impact athletic training and competition. The purpose of this study is to evaluate the prevalence of vitamin D deficiency in university athletes and inactive controls in spring and autumn. During this study the subjects will be asked to visit the labs on two occasions, at the beginning of the study for baseline measurements, and again on two occasions at the end of the study. Participants will have the following outcomes assessed: Sport performance (vertical jump height, muscular strength and aerobic fitness), peripheral Quantitative Computed Tomography (pQCT) scan of the bone mineral composition of the tibia, total body composition via Dual Energy X-ray Absorptiometry (DEXA),total and hip/femoral head bone mineral density and content to assess fracture risk via DEXA. Serum 25(OH)D levels (≈15ml of whole blood will be collected for these measurements. Dietary intake using self-reported food diaries. In addition illness and injury incidence will be recorded daily throughout the study in a booklet provided to the participants.Throughout the trial, the participants will be contacted via telephone/ email on a monthly basis to discuss any issues and maintain good communication.