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5 Ways That Vitamin D Makes You a Better Athlete

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Vitamin D provides a number of benefits relating to health and well-being. It decreases the risk of cardiovascular disease, diabetes, stroke and multiple sclerosis. It also supports strong bones and teeth too.

But not only does this wonder vitamin help to keep you healthy, there’s evidence that it can also help with athletic performance as well.

In this article we’ll give you the top 5 reasons why vitamin D will make you a better athlete. If you take your fitness seriously or you’re a competitive athlete you’ll definitely want to give this one a read.

What is Vitamin D?

There are two types of vitamin D – D2 (ergocalciferol) and D3 (cholecalciferol). D3 is more biologically active and potent of the two.

Although classed as a vitamin, D3 is also referred to as the sixth steroid hormone due to its role in supporting hormones such as testosterone. It is a fat soluble hormone, often called the ‘sunshine vitamin’ as it is produced in the body when sunlight comes into contact with the skin.

D3 is essential for regulating calcium in skeletal tissues which helps to maintain healthy bones and teeth, and has been linked to a protective effect against cardiovascular disease, diabetes and some forms of cancer too.

We now know that this important nutrient can support athletes too. But it is clear that not all athletes are getting enough to maximize performance. 

Whilst you get this nutrient from exposure to the sun, you also get a limited amount from some foods such as oily fish and dairy products. But as more and more research is made available though it is clear that this is not enough.

In a systematic review of over 2,300 athletes in 2015, as many as 56% of them had insufficient levels of the nutrient [1].

It is therefore increasingly important that not only those that want to decrease long-term risk of illness, but athletes too focus on how this nutrient might improve their performance.

Here are the top 5 reasons why vitamin D needs to be optimized in competitive athletes or anyone else that takes their fitness seriously… 

#1. Reduces Muscle Soreness

One of the big limiting factors in the ability to train regularly and intensely is the soreness you get in the days following exercise sessions. Delayed onset of muscle soreness – simply referred to as DOMS – is a metabolic side effect of microscopic muscle damage and inflammation.

You’ve probably had the feeling already – you wake up the morning following a big session and you feel tight and sore. As the day progresses it gets worse. If you had a particularly big session you’ll feel even the day after – typically, DOMS lasts around 24-72 hours after exercise, until the damage has been restored.

Of course, whilst it’s not suggested you miss exercise because of soreness, in reality you’ll just not train as hard which means less productive sessions. Being fit, well and free of soreness allows you train maximally and force the body to adapt ready for competition.

Studies show that vitamin D3 can speed up micro-trauma recovery. In one study from Nutrition & Metabolism [2], a group of athletes were given 4000IU of D3 per day, and after 28 days were given an exercise program to induce DOMS.

The results found that in those taking the supplement, recovery accelerated by nearly 50% – a huge amount.

#2. Better Cognition

Successful athletes don’t only have excellent motor skills and physical athleticism, they also have outstanding cognitive ability too [3].

Memory, focus, attention and problem solving are all important aspects of total fitness – particularly in competitive sport where the athlete has to better their opponent with cognitive reasoning, just as much as with physical capabilities.

It has long been thought that due to vitamin D receptors being present in the brain, deficiencies can impair its ability to process incoming information needed for peak performance [4].

One cross-section study found that low levels of the sunshine vitamin were correlated with impairment of two out of four cognitive tests [5].

Another study found that when older subjects were split into groups of insufficient and optimal D3 levels, those with low amounts had poorer performance across a range of mental tasks and tests [6].

#3. Increased Testosterone

Testosterone is an important hormone for any athlete as it promotes strength, muscle growth and optimal body composition.

Vitamin D has long been thought to augment testosterone production, but research has previously been limited to those with metabolic illnesses. But there is now an ever-emerging bank of research studies to show that it can also boost athleticism as well.

Low T levels are a sign of excess training load or overtraining. As a precursor to testosterone production, D3 improves the binding efficiency of male hormone which in turn reduces the chances of burn out or fatigue [7].

Testosterone is a key marker of masculinity and athleticism and needs to be optimized for success. Low levels means less power, strength and overall fitness.

#4. Boost Immune System

Vitamin D plays a clear role in immune system health as its receptors are expressed on white blood cells [8]. It basically triggers the cells whose job it is to fight incoming viruses and bacteria.

One thing to bear in mind of course is that seasonal illnesses are always highest in the winter – the season where sunlight is at its lowest. The link between the two is quite clear.

One particularly large study measured vitamin D levels in almost 19,000 people over a 6 year period [9]. Those with lower levels were more likely to report problems with common colds and upper respiratory tract infections – a common type of illness in athletes. This was even after age, body mass and race had been accounted for.

In another interesting study, 800 Finnish military recruits were observed over a 6-month period [10]. Those with higher levels of the nutrient had significantly fewer days of absence than those with low levels of the sunshine hormone. They were also able to exercise more frequently too, presumably leading to better fitness levels.

#5. Improves Endurance

Another key indicator of successful sports performance is that of endurance – a tired athlete can’t perform optimally, so any improvement in fitness gives you a clear advantage as a competitor.

Endurance is often measured in athletes using VO2max – a test that measures the maximum volume of oxygen that an athlete can use at any one time. It is a gold-standard test with high VO2max results correlating well with success in endurance based sports.

A study published in 2014 used elite rowers and gave them a high dose of vitamin D to measure its effects on fitness [11]. After the study, the athletes who’d used the supplement significantly improved their VO2max.

Likewise, a study reported reduced inflammation and benefits to power output in a group of healthy adults after 35 days of supplementation [12].


Vitamin D is well known for its ability to improve cardiovascular and metabolic health as well as providing a neuroprotective effect.

It is also an essential vitamin that can boost athletic performance by improving anabolic hormone levels, reduce the occurrence of illness during phases of intense training and improve endurance.

As an athlete you’ll want to optimize levels of vitamin D by ensuring regular exposure to sunlight, eating a diet rich in oily fish and considering a high-quality supplement that provides a high dose of this wonder nutrient.


  1. Farrokhyer, F et al. Prevalence of Vitamin D Inadequacy in Athletes: A Systematic Review and Meta-Analysis. Sports Med. 2015; 45(3): 365-78
  2. Barker, T et al. Supplemental vitamin D enhances the recovery in peak isometric force shortly after intense exercise. Nutr Metab (Lond) 2013; 10: 69
  3. Ruiz, N et al. Teaching Athletes Cognitive Skills: Detecting Cognitive Load in Speech Input. BCS ’10 Proceedings of the 24th BCS Interaction Specialist Group Conference’. 484-488
  4. Kenny, AM et al. Effects of vitamin D supplementation on strength, physical function, and health perception in older, community-dwelling men. J Am Geriatr Soc. 2003; 51(12): 1762-7
  5. Wilkins, CH et al. Vitamin D Deficiency Is Associated With Low Mood and Worse Cognitive Performance in Older Adults. Am J Geriatr Psych. 2006; 14(12): 1032-1040
  6. Dickens, AP et al. Vitamin D, cognitive dysfunction and dementia in older adults. CNS Drugs. 2011; 25(8): 629–639
  7. Halson, SL et al. Does overtraining exist? An analysis of overreaching and overtraining research. Sports Med. 2004; 34(14): 967-81
  8. Aranow, C. Vitamin D and the immune system. J Investig Med. 2011; 59(6): 881-886
  9. Ginde, AA et al. Association between serum 25-hydroxyvitamin D level and upper respiratory tract infection in the Third National Health and Nutrition Examination Survey. Arch Intern Med. 2009; 169(4): 384-90
  10. Laaksi I. An association of serum vitamin D concentrations < 40 nmol/L with acute respiratory tract infection in young Finnish men. Am J Clin Nutr. 2007; 86(3): 714-7
  11. Jastrzebski, Z. Effect of vitamin D supplementation on the level of physical fitness and blood parameters of rowers during the 8-week high intensity training. Facicula Educ Fiz si Sport. 2014; 2:57-67
  12. Barker, T et al. Supplemental vitamin D enhances the recovery in peak isometric force shortly after intense exercise. Nutr Metab. 2013; 10:69