Vitamin D and Athletic Performance

For thousands of years, elite athletes have turned to the sun’s energy to optimize performance and physical fitness. The sun triggers the production of many hormones and peptides in the human body, including vitamin D. Despite being called a vitamin, vitamin D actually acts as a hormone. Vitamin D has widespread health implications and impacts many different systems of the body that affect sports performance.  

Athletes across the world are severely lacking in sunlight and vitamin D. In fact, nearly 80% of professional and collegiate athletes have inadequate vitamin D levels. Research demonstrates this leads to increased injuries, slower recovery, and reduced performance.[2] 

Can vitamin D reduce injury? 

It is well established that vitamin D plays an important role in bone health and fracture prevention, due to its role in moderating calcium uptake. Genes that are affected by vitamin D are involved in bone health, muscle strength and size, balance and coordination, inflammation and more.[3] 

Athletes with low vitamin D levels are at higher risk of missing practices and games due to stress fractures, muscle injuries, upper respiratory tract infections and delayed muscle recovery. Athletes in a state of deficiency experience muscle fiber atrophy, slow peak muscle contraction, prolonged time to muscle relaxation, and an increased risk of chronic musculoskeletal pain. Increased levels of vitamin D have been shown to lead to decreased muscle protein degeneration.[4,5] Maintaining adequate vitamin D levels is a critical component to preventing and recovering from injury.

Can vitamin D speed athletic recovery? 

Lower vitamin D levels have been found to be associated with increased muscle weakness for up to 72 hours after intense exercise.[6] The light spectrum that produces vitamin D triggers mechanisms that speed recovery time by improving muscle healing between workouts or following injury, which has a huge impact on the lifespan of an athlete’s career. 

In a randomized, double-blind, placebo-controlled study that compared a non-supplement group and supplement group given 4000 IU of vitamin D per day, peak power output after intense exercise decreased 26% more without supplementation.[7] Another study that investigated vitamin D level and skeletal muscle repair found that increasing vitamin D level from 40 to 75 nmol/L resulted in improved recovery from weight-bearing exercise at 48 hours and 7 days after exercise compared to a placebo control group.[8]

Does vitamin D improve athletic performance? 

Vitamin D is associated with increased muscle protein synthesis, testosterone levels, ATP concentration, and inflammatory modulation, which improves muscle strength, jump height, velocity, power, balance, exercise capacity, and overall physical performance.[4] Studies show that vitamin D activates the expression of genes that influence growth of Type II fast-twitch muscle fibers.[9] These types of muscles control the powerful, quick movements that are required in many sports. One study of 1,377 subjects found that those with the highest vitamin D levels showed an up to 25% higher exercise capacity compared to those with the lowest vitamin D levels.[10] 

While the impact of vitamin D on physical fitness is an emerging and exciting field of study, ancient Romans documented improved performance with midday sunlight. In the 1950’s German and Russian Olympic teams used full spectrum lights (with high skin cancer risk).[9] With advancements in scientific diagnostics, we now understand why these methods were so effective and how to harness the benefits of these types of treatment while making them safer. 

Increasing vitamin D for sports performance

Unfortunately, current solutions for increasing vitamin D levels are not working. Oral vitamin D supplements are not effective for a surprisingly large number of people. Millions of people have a fat malabsorption condition (cystic fibrosis, Crohn’s disease, celiac, liver disease, etc.) that prevents them from absorbing fat-soluble vitamin D supplements. Additionally, oral intake of vitamin D bypasses the body’s natural regulatory processes, leading to potential harm and lacking in efficacy. It is critical to avoid excessive doses of oral vitamin D. If vitamin D intake is too high, it can cause vitamin D toxicity, also known as hypervitaminosis D. 

You cannot overdose on vitamin D that is stimulated by light and produced in your skin. If you have enough vitamin D, your body will simply produce less. Using light to make vitamin D allows your body to self-regulate production and make as much as it needs to stay healthy, without any risk of overdose or toxicity.