Assessment of vitamin D concentration in non-supplemented professional athletes and healthy adults during the winter months in the UK: implications for skeletal muscle function.
J Sports Sci. 2012 Oct 22.
Close GL, Russell J, Cobley JN, Owens DJ, Wilson G, Gregson W, Fraser WD, Morton JP.
a Muscle Metabolism and Physiology Research group, Research Institute for Sport and Exercise Sciences , Liverpool John Moores University , Liverpool , UK.
Abstract The current study implemented a two-part design to (1) assess the vitamin D concentration of a large cohort of non-vitamin D supplemented UK-based athletes and 30 age-matched healthy non-athletes and (2) to examine the effects of 5000 IU · day(-1) vitamin D(3) supplementation for 8-weeks on musculoskeletal performance in a placebo controlled trial. Vitamin D concentration was determined as severely deficient if serum 25(OH)D < 12.5 nmol · l(-1), deficient 12.5-30 nmol · l(-1) and inadequate 30-50 nmol · l(-1).
We demonstrate that 62% of the athletes (38/61) and 73% of the controls (22/30) exhibited serum total 25(OH)D < 50 nmol · l(-1).
Additionally, vitamin D supplementation increased serum total 25(OH)D from baseline (mean ± SD = 29 ± 25 to 103 ± 25 nmol · l(-1), P = 0.0028), whereas the placebo showed no significant change (53 ± 29 to 74 ± 24 nmol · l(-1), P = 0.12).
There was a significant increase in
- 10 m sprint times (P = 0.008) and
- (vertical-jump (P = 0.008)
in the vitamin D group whereas the placebo showed no change (P = 0.587 and P = 0.204 respectively).
The current data supports previous findings that athletes living at Northerly latitudes (UK = 53° N) exhibit inadequate vitamin D concentrations (<50 nmol · l(-1)).
Additionally the data suggests that inadequate vitamin D concentration is detrimental to musculoskeletal performance in athletes.
Future studies using larger athletic groups are now warranted.
See also VitaminDWiki
Professional sports team takes 5000 IU vitamin D and wins championship Hockey
5,000 IU daily was just enough vitamin D for Irish athletes in the winter – March 2013
Overview Sports and vitamin D which has the following summary Oct 2012
- Athletes are helped by vitamin D by:
- Faster reaction time
- Far fewer colds/flues during the winter
- Less sore/tired after a workout
- Fewer micro-cracks and broken bones
- Bones which do break heal much more quickly
- Increased VO2 and exercise endurance Feb 2011
- Indoor athletes especially need vitamin D
- Professional indoor athletes are starting to supplement with vitamin D or use vitamin D beds
- Olympic athletes have used UV/vitamin D since the 1930's
- The biggest gain from the use of vitamin D is by those who exercise less than 2 hours per day.