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Study proves it: Vitamin D improves performance

December 7, 2018

When it comes to increasing physical performance with micronutrients, very few athletes think of vitamin D. Thanks to a recent study, however, the sun vitamin is shining in a new light. While it was previously associated with strong bones, it has now almost earned the title "fitness supplement".

In a recently published study, A. Marawan et al. from Virginia Commonwealth University (VCU) investigated the relationship between vitamin D levels and cardiorespiratory fitness (CRF) in adults. The term cardiorespiratory describes the ability of the heart and lungs to supply the muscles with oxygen during exercise. In this context, the term aerobic endurance is often used. It is determined by measuring the maximal oxygen consumption (VO₂ max) during training. Higher cardiorespiratory fitness not only ensures better athletic performance, but also protects against chronic diseases.

Vitamin D and cardiorespiratory fitness

The research was based on data from the American Nation Health and Nutrition Survey. They analysed 1,995 adults aged 20-49 years. The US researchers compared the maximum oxygen consumption VO₂max (as an indicator of CRF) with the vitamin D levels in the blood.

The result:

People with high vitamin D levels had a significantly higher CRF than participants with low levels. Even when so-called confounding factors such as weight, age, gender, high blood pressure and smoking were included in the analysis, a clear correlation between vitamin D levels and cardiorespiratory fitness was evident. Furthermore, it was shown that every 10 nmol/l increase in blood vitamin D levels led to a 0.78 ml/kg/min increase in VO₂ max. This means that there is a so-called dose-response relationship and that every increase in vitamin D is associated with an increase in performance.

The researchers now want to conduct clinical studies to find out exactly how vitamin D supplementation affects physical performance and what amounts are optimal.

Conclusion:

Dr Amr Marawan, head of the study, summarises the results: "Our study shows that a higher vitamin D level is associated with better performance. We also know from previous research that vitamin D has positive effects on the heart and bones. Make sure your vitamin D level is normal to high."

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Why supplementing with vitamin D makes sense

Vitamin D is often referred to as the super vitamin. And rightly so, because we need the sun vitamin for healthy bones, muscles and a strong immune system. Vitamin D is also said to protect against diseases such as cancer, diabetes, high blood pressure, dementia and depression. However, studies by the Robert Koch Institute show that the majority of Germans are not optimally supplied with vitamin D.

With sufficient sunlight, the body can produce vitamin D itself. However, in the dark season (October - March), this is no longer intense enough and supplementation is recommended. With increasing age, the skin's synthesis capacity decreases significantly. People aged 65 and over should therefore take supplements all year round.

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