Tremors. No, not the Kevin Bacon flick from 1990. Muscle tremors — the quivering or mini-cramps you sometimes experience in your muscles post-workout. As your body cools down, the restless feeling typically subsides. But what’s going on if the twitching doesn’t stop?
According to the National Institute of Neurological Disorders and Stroke, roughly 10 percent of the population suffers from Restless Legs Syndrome. RLS often comes with more symptoms than involuntary movement, such as throbbing, itching, and an irresistible urge to move a limb (despite the name, this urge isn’t exclusive to the legs). Also, it’s common for symptoms to worsen at night. So, if your limbs are quivering or twitching hours post-workout, the issue could potentially be RLS. If it is, a doctor will have to sort that out for you. That said, it could also be a magnesium deficiency.
“Calcium tenses muscles and magnesium helps relax muscles,” explains Denis Faye, Openfit’s Director of Nutrition Content. “Most people get enough calcium in their diets, but that’s not always the case with magnesium.”
Many things can cause magnesium depletion, including sweating (read: exercise), stress, and caffeinated or alcoholic beverages. “Some medications, such as antibiotics, diuretics, and oral contraceptives have also been found to be linked to lower blood magnesium levels,” adds Faye. “The reason to take these, of course, outweighs the negative impact, but you might want to eat more magnesium-rich foods.”
Adding leafy greens, nuts, and seeds to your shopping cart will help. More specifically, per serving, almonds, cashews, peanut butter, brown rice, salmon, chicken breast, spinach, black beans, oatmeal, bananas, and milk are high in magnesium.
There are also magnesium supplements. However, if you’re someone who already loads up on supps, Faye recommends cutting back as you attempt to figure out what’s causing your restless legs.
“People will often pull double duty with their supplements and take a multivitamin, a B-complex vitamin, and all of this other stuff,” he says. “I’d go cold turkey and remove everything. A multivitamin is a nice baseline if you’re in a calorie deficit—as many people are—then I’d suggest adding things one by one based on your individual issues. I’m also a believer that you should be getting as many nutrients as you can from food. Target your supplement use. For example, if I have inflammation, I’ll take fish oil. Or if I’m working out hard, I’ll take magnesium.”
The recommended daily dose of magnesium varies by age and gender, but ballpark numbers fall around 300-420 mg per day for men and women, respectively. That said, athletes and weightlifters that engage in vigorous exercise and sweat profusely may require more. How will you know if you go overboard with the magnesium? “By the high number of bathroom breaks,” says Faye.