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CHAPTER 32
THE SUN—
Vitamin D and Athletic Performance
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Does spending more time in the sun improve athletic performance?
The ancient Greeks believed athletes should be well bathed by the sun, and their elite athletes trained at the beach and in the nude. The latter might be difficult in today’s world, but if your vitamin D levels are too low, the sun can definitely improve your training and racing performance; and in a healthy way. Research indicates that normal vitamin D levels are associated with peak athletic performance. However, a surprising number of athletes have low levels of vitamin D, often because they prevent normal vitamin D production by using sunscreen, avoiding midday sun exposure, and overdressing.
It’s important to balance minimizing overexposure to the sun (avoiding sunburn) with obtaining enough sun exposure to allow for sufficient vitamin D production. Normalizing vitamin D levels can improve muscle function, prevent bone problems, help with recovery from training and competition, reduce unexplained muscle pains, and prevent many health problems including many forms of cancer. Normal vitamin D levels may also prevent getting sunburned during long training and racing.
While vitamin D is called a “vitamin,” it’s really a unique steroid hormone that helps control inflammation and immunity, while improving brain and hormone function, regulating calcium absorption and utilization, and promoting the work of several thousand genes.
Balance minimizing overexposure to the sun (avoiding sunburn) with obtaining enough sun exposure to allow for sufficient vitamin D production.
For decades, I found low vitamin D levels in athletes I treated. I would then recommend they spend more time in the sun. While this advice resulted in my receiving some nasty letters from dermatologists, current research has shown that the vitamin D-deficit problem is real. A study published in the International Journal of Sports revealed that a group of French cyclists, each training sixteen hours a week outdoors, had below-normal levels of vitamin D. Two other current studies measuring large numbers of people in southern Florida and southern Arizona showed significantly high numbers of people were also far below normal levels of vitamin D, despite living in sunny environments.
The key factors associated with an athlete not getting sufficient vitamin D include:
- Using sunscreen that blocks the vitamin D-producing ultraviolet B (UVB) waves of the sun.
- Wearing protective clothing, especially materials that block UVB waves.
- Training early and later in the day, when vitamin D-producing sun exposure is significantly reduced.
- Darker skin. Even many light-skinned athletes have accumulated enough sun to darken their skin to the point where it reduces their ability to obtain vitamin D from sun exposure. As a result, they need to be in the sun longer to obtain the same amount of D.
- Proper fat metabolism is necessary for vitamin D production, and those with too high and too low body fat may be unable to release stored vitamin D, which is especially important in winter and early spring when sun exposure produces much less vitamin D.
- Athletes living at more extreme latitudes, such as northern Europe and Canada, and southern Australia and South America, have significantly less sun exposure throughout the year.
