None listed
Conditions
Brief summary
In a recent survey of Dunedin and Invercargill residents, 49% had low serum Vitamin D levels. Vitamin D may be important for the growth, repair and function of skeletal muscle, yet little is known about the effects of vitamin D supplements on muscle and athletic performance. Our project is designed to determine whether rugby union players in Otago and Southland are deficient in vitamin D, and whether supplementing them with vitamin D enables them to gain more muscle mass, and become stronger and faster as they progress through their pre-season training.
Interventions
Oral Vitamin D supplementation (50,000 IU cholecalciferol) or placebo taken once a fortnight over 11-12 weeks of pre-season training for the New Zealand ITM Cup domestic rugby union competition. The duration of treatment is designed to coincide with local performance testing (done at 5 and 11 weeks in one squad, and after 6 and 12 weeks in the other squad). The supplementation is taken as a single oral tablet (Cal-D-Forte, PSM Healthcare Ltd, Auckland NZ) once a fortnight.
Sponsors
Dr Kirsty Fairbairn
Study design
Allocation
Randomised controlled trial
Intervention model
Parallel
Primary purpose
Treatment
Masking
Blinded (masking used)
Eligibility
Sex/Gender
Male
Age
18 Years to 40 Years
Healthy volunteers
Yes
Inclusion criteria
Rugby players training in the Otago and Southland ITM Cup pre-season training squads, including development players. Aged 18 years and over, and able to undergo strength and speed testing.
Exclusion criteria
Aged under 18 years of age; currently taking Vitamin D supplements; the presence of any chronic disease such as heart disease, diabetes or cancer; the presence of any conditions that affect hormone metabolism (primarily growth hormone and insulin metabolism); smokers.
Outcome results
None listed