Tip The Strength Vitamin Search Skip to content Menu Menu follow us Store Articles Community Loyal-T Club Loyal-T Points Rewards Subscribe to Save Search Search The World s Trusted Source & Community for Elite Fitness EatingSupplements Tip The Strength Vitamin Most athletes have low levels of this vitamin And only one type of it will keep your strength gains coming Here' s the science by Shawn Wayland December 23, 2017August 30, 2022 Tags Building Muscle, Nutrition & Supplements, Tips, Vitamin D Short winter days could affect you more than you think. The lack of sunlight on your skin in the cold months can leave you with low levels of vitamin D, which may be limiting your strength gains in the gym. In a systematic review by Chiang et. al, six studies involving athletic subjects between the ages of 18 and 45 were analyzed. The studies used varying doses of D2 and D3 (both precursors to active vitamin D in the body) and tested strength using various methods. Two of the studies supplemented with D2, which showed no significant differences in strength between the control and experimental group. In the four studies examining D3 supplementation, two of them showed significant increases in strength, and two showed no difference in strength. However, the two D3 studies that showed no statistically significant differences between the control and experimental group did still increase strength. With the study noting that up to 80% of athletes could be deficient in vitamin D, supplementing – especially during the winter when sunlight exposure is low – is crucial. The two types of vitamin D are not treated equally by the body. D2 won't increase levels of 25(OH)D – vitamin D in the body – while D3 will. The researchers recommend 2,000 IU of D3 daily for 8-12 weeks to increase levels. The optimal levels of vitamin D in the body are disputed by researchers and the Institute of Medicine and the Endocrine Society. It seems levels close to 50 ng/ml of 25(OH)D are best for the athletic population and strength display, and the average subject values pooled from all the studies in the review had a value of 23.59 ng/ml. With the high prevalence of suboptimal vitamin D levels, supplementation is most likely beneficial, if not necessary, in most of the population, both athletic and non-athletic. If you want to be certain, a simple blood test will allow you to see your serum levels and let you monitor it throughout the year. Chiang CM et al. Effects of vitamin D supplementation on muscle strength in athletes: A systematic review. J Strength Cond Res. 2017 Feb;31(2):566-574. PubMed. Get The T Nation Newsletters Don' t Miss Out Expert Insights To Get Stronger, Gain Muscle Faster, And Take Your Lifting To The Next Level related posts Supplements Curcumin Makes Fat Cells Kill Themselves New research shows that curcumin prevents baby fat cells from becoming adults while also causing adult fat cells to commit suicide. Losing Fat, Nutrition & Supplements TC Luoma February 28 Eating Tip Use This Simple Trick to Cook Eggs An easy way to keep a great protein source handy. Check out this kitchen hack. Feeding the Ideal Body, Nutrition & Supplements, Tips Chris Shugart February 28 Supplements The Happy Powder Low energy? No motivation? Lack of focus? Feeling mentally or physically run down? There's a supplement for that. Nutrition & Supplements, Workout Nutrition Christian Thibaudeau December 27 Diet & Fat Loss December Diet Strategies Thanksgiving was a fatty, sugary good time. I've never been one to do the old "modified recipe" thing when it comes to traditional holidays. Mashed potatoes and gravy, eggnog, pumpkin pie – it's all good to me. Feeding the Ideal Body, Nutrition & Supplements Lonnie Lowery, PhD December 19