A Prospective Trial on the Effects of Vitamin D Supplementation on 25(OH)D, Body Composition and Injury in Collegiate Swimmers and Divers
Trial Snapshot
- Phase
- Phase 3
- Status
- Completed
- Sponsor
- University of Kentucky
- Enrollment
- 45
- Locations
- 1
- Primary Endpoint
- 25(OH)D)
Study Overview
Brief Summary
Objective 1: Determine if Vitamin D supplementation can improve body composition, reduce injuries and illnesses, and improve performance in collegiate swimmers and divers.
Objective 2: Examine how baseline Vitamin D levels predict outcome variables over the course of the intervention period.
Detailed Description
The investigators plan to recruit from approximately 45 male and female University of Kentucky Swimmers and Divers, at least 18 years of age in August 2011. Approximately equal numbers of men and women will be recruited. The entire athletic team(s) will be recruited. With a conservative dropout rate of 30%, the investigators final sample size should be approximately 22 participants (per group).Following baseline measures, participants will be randomized to one of two groups (Vitamin D 4000 IU or Placebo control) and monitored over the course of their athletic season. Measurements will be repeated at Midpoint (3 months) and Endpoint (6 months).
Participants will have no recent history of Vitamin D supplementation beyond what is normally found in a multivitamin (400 IUs).
Following the informed consent process a medical history and Vitamin D questionnaire (screenings), and urine pregnancy test (for female athletes) will be administered prior to more invasive baseline testing procedures (blood draw and DXA). A blood draw will then be conducted at baseline, midpoint and endpoint. Collected blood for the purposes of this study will assess Vitamin D status (25(OH)D), parathyroid hormone, ionized calcium, bone turnover markers, and inflammatory cytokines. A Vitamin D lifestyle questionnaire will be administered at all 3 time points and incidence of illness and injury will be documented over 6 months following randomization. DXA measures will only occur at Baseline and Endpoint.
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Parallel
- Masking
- Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Eligibility Criteria
- Ages
- 18 Years to — (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- Yes
Inclusion Criteria
- •University of Kentucky Swimmers and Divers, at least 18 years old.
- •No recent history of Vitamin D supplementation beyond 400IU
Exclusion Criteria
- •hormone replacement therapy,
- •high dose Vitamin D supplementation,
- •history of renal disease or kidney stones,
- •organ transplantation,
- •sarcoidosis,
- •parathyroid disease,
- •history of high blood calcium levels.
Arms & Interventions
Oil pill
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Intervention: Placebo (Dietary Supplement)
Vitamin D
Vitamin D
Intervention: Vitamin D (Dietary Supplement)
Outcomes
Primary Outcomes
25(OH)D)
Time Frame: 3 measurement periods over 6 months
Baseline, Midpoint, and Endpoint measures include a blood draw for 25(OH)D status.
Secondary Outcomes
- Inflammatory Cytokines(Baseline and Enpoint)
- Bone Turnover Markers(Baseline, Midpoint, Endpoint)
- DXA Body Composition(Baseline and Endpoint)
- Vitamin D Lifestyle Survey(Baseline, Midpoint, Endpoint)
- injury and illness incidence(6 months)