Int J Sport Nutr Exerc Metab. 2015 Dec 16. Epub ahead of print
Wentz LM1, Liu PY, Ilich JZ, Haymes EM.
Department of Nutrition Science, East Carolina University, Greenville, NC.
High rates of vitamin D deficiency have been reported in athletes. The purpose of this study was to evaluate the associations between vitamin D and bone health, and parathyroid hormone (PTH) concentrations in female runners who trained at 30.4° degrees north.
Serum 25-hydroxyvitamin D (25(OH)D), PTH, body composition, and bone mineral density (BMD) were measured in 59 female runners, aged 18-40 years. Stress fracture history, training duration and frequency were evaluated by questionnaire. As per National Endocrine Society cut-offs, serum vitamin D ranges were: 25(OH)D < 50 nmol/L for deficient; 50-75 nmol/L for insufficient; and ≥ 75 nmol/L for sufficient status.
Mean serum 25(OH)D concentrations were 122.6±63.9 nmol/L, with 18.6% of subjects in the deficient (5.1%) or insufficient (13.5%) range. No significant differences were observed between sufficient and deficient/insufficient subjects for BMD, PTH, history of stress fractures, or demographic data.
The majority of distance runners maintained sufficient vitamin D status, suggesting that training outdoors in latitude where vitamin D synthesis occurs year-round reduces the risk for vitamin D deficiency. Data do not support the indiscriminate supplementation of outdoor athletes in southern latitudes without prior screening.
Outdoor activities prescribed by 20 French doctors to treat diseases associated with low vitamin D – Nov 2015
Elite outdoor athletes had 52 ng of vitamin D – March 2013
Overview Sports and vitamin D has the following summary
Athletes are helped by vitamin D by:
- Faster reaction time
- Far fewer colds/flus 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.
- Reduced muscle fatigue with 10,000 IU vitamin D daily
- Muscle strength improved when vitamin D added: 3 Meta-analysis
- Sports and Vitamin D category