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As if it were made for weightlifters, vitamin D promotes testosterone, type-2 muscle fiber development, and bone density.
Plus, it’s that time of year when we find ourselves echoing that fateful warning forever crystallized by Game of Thrones: Winter is coming.
For most of us, winter comes with less sun exposure, which causes dips in vitamin D levels – often into the deficiency category.
Lifters are especially vulnerable to vitamin D deficiencies because of this micronutrient’s importance in both bone and muscle repair and synthesis.
Here’s why every weightlifter – and as it turns out, older folks as well – needs to pay extra attention to their vitamin D levels.
When a strength athlete’s muscles are performing under a workload, be it steady or intermittent, the tendon that joins each involved muscle to the bone it moves has to pull really hard and really frequently on the bony attachment sites.
Additionally, athletes of all kinds send shockwaves through their skeletal framework with every step, jump, punch, and so forth.
Both of these stressors demand a high bone density if injury is to be prevented.
Supplementing high doses of vitamin D when you’re not deficient isn’t likely to boost bone density very much. Also, vitamin D is rendered much less effective without calcium.
Vitamin D does in fact support bone density, but there are a couple of very important caveats to consider here.
First, supplementing high doses of vitamin D when you’re not deficient to begin with isn’t likely to boost bone density very much (effect is more significant when transitioning from deficient to healthy intake).
Also, vitamin D is rendered much less effective without calcium.
This study by North Hospital Group in Amiens, France clearly illuminates these conditions by including calcium intake and pre-trial levels of bone density as indicators of vitamin D deficiency.
In the randomized clinical trial, participants were administered 500mg of calcium and 800IU of vitamin D a day for 12 months, after which they demonstrated clinically significant increases in bone density at the “lumbar spine, femur, trochanter, and whole body.”
When all the boxes are checked, vitamin D is integral to bone density.
Research has correlated certain levels of vitamin D supplementation with increased levels of free testosterone in men.
Since this hormone is key to maintaining and increasing muscle mass (and even better, it helps on the bone density front as well), this relationship bodes well for weightlifters and the general public.
This study from the Medical University of Graz in Austria observed “a significant increase in total testosterone levels … bioactive testosterone … and free testosterone levels” in participants who were given vitamin D for a year.
The lesser known ability of vitamin D to directly support muscle health is starting to gain more attention, as in this Clinical Science of London study that took muscle biopsies of ageing participants given a “vitamin D analogue” over the course of 3-6 months.
The findings revealed two highly important trends.
First, enzymes directly correlated with oxidative capacity (succinate dehydrogenase and total phosphorylase) increased with vitamin D supplementation.
Oxidative capacity is the ability of muscle tissue to efficiently take in and make use of oxygen; the higher the capacity, the more a muscle can perform with the same supply of oxygen coming in.
Vitamin D also increased fast-twitch muscle fiber (type II A), which is helpful for elderly people with osteoporosis in preventing a fall as well as athletic performance in younger people.
According to the Food and Nutrition Board (FNB) of the National Academies of Sciences, the RDA for vitamin D varies between 10-20 micrograms depending on age and gender.
In your own research, you may also see the “IU” unit being thrown around, which stands for international unit.
One microgram equals fifteen IU, so the aforementioned RDA range in IU is 150-300.
To provide a bit of scale, there are approximately 3 micrograms/45 IU of vitamin D in an egg yolk.
Other foods containing vitamin D include:
While a base level of sun exposure can be healthy for more than just vitamin D synthesis, prolonged exposure is emphatically urged against by the majority of healthcare experts.
For example, Yale Medicine dermatologist David J. Leffell stated “As a doctor who treats patients who have melanomas, I want the general public to be advised that under no circumstances can use of a tanning bed or tanning in general be justified on the basis of vitamin D. Take a supplement instead.”
Whether it’s wintertime or not, if you’re concerned about your vitamin D intake, the next best place to look after dietary changes is supplementation.
For a super simple, effective, and affordable way to reach your vitamin D RDA consistently, we recommend Vitamin D3 liquid softgels from Healthy Origins.
Each serving of these highly absorbable, gluten-free and preservative-free softgels provides a whopping 5,000 IU, which meets the RDA several times over.
Healthy Origins softgels are made with a form of vitamin D3 called cholecalciferol, and the only other ingredients include cold-pressed olive oil, gelatin, glycerin, and water.
Even after you’ve racked those dumbbells for the last time—if the day ever comes—getting in the habit of vitamin D supplementation will benefit you just as much, if not more, down the road.
The studies above and many contemporary findings agree that vitamin D is a vital micronutrient for lifters and the elderly alike, since maintaining bone density and strong muscles is important for fall/injury prevention and functional independence.
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