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There’s a lot to love about working out. Whether you’re in it for the physical benefits or to maintain your sanity, there’s a lot to be gained from getting your sweat on. But one common side effect that isn’t so great? Muscle cramps.
It’s a tale as old as time: There you are, drop-setting at the end of a grueling lifting sesh, just hitting the halfway mark on a lengthy run, or maybe even sprinting it out during a pickup soccer game when boom — a cramp strikes. You may be figuring that you just didn’t hydrate enough, and you’re onto something. The catch-22 that most athletes are familiar with is the fact that chugging too much water (or any other beverage) just before a workout or midactivity can make matters worse.
A recent study found that even if you show up prepared and drink enough as you work out, plain water might not be the key to killing cramps. Instead, electrolytes, which include minerals like sodium, potassium, magnesium and chloride, might be the heroes of the game — literally.
The small study, published in the Journal of the International Society of Sports Nutrition, found that people who drank water boosted with electrolytes fared better than those who sipped on plain ol’ water when it came to cramps during and after exercise. The study built on previous evidence that a lack of electrolytes, not just inadequate hydration, contributes to the risk of cramping up.
To test the methods against each other, researchers had 10 men run on a downhill treadmill in a 95-degree room for 40 to 60 minutes until they lost 1.5 to 2 percent of their bodyweight in sweat. The runners either drank plain spring water or a rehydration drink with electrolytes, and researchers used electrical stimulation on the runners’ calves to induce cramps. The idea is that the less stimulation it took to cause cramping, the more prone the person was to getting a cramp at some point sans electrical stimulation.
“We found that the electrical frequency required to induce cramps increased when people drank the electrolyte water but decreased when they consumed plain water,” said Kazunori Nosaka, Ph.D., professor at Edith Cowan University in Australia and lead author of the study, in a release. “This indicates that muscles become more prone to cramps by drinking plain water but more immune to muscle cramps by drinking the electrolyte water.”
The fact that electrolytes are beneficial to athletic performance is nothing new — there’s a reason the term “sports drink” is pretty much synonymous with “any beverage with added electrolytes” — but one potential take-away from the small-scale study is that drinking plain water actually made athletes more prone to cramps. It may be worth having electrolyte tablets or a basic hydration drink on hand, just to be safe. In any case, electrolytes will definitely help you rehydrate.
“Electrolytes are vital to good health — they help the body absorb water more effectively than plain water and replace essential minerals lost through sweat or illness,” Nosaka said. “People should consider drinking oral rehydration fluids instead of plain water during moderate to intense exercise, when it’s very hot, or when you are sick from diarrhea or vomiting.”
While this study was small and only included male participants, it’s safe to say that drinking something with electrolytes certainly won’t hurt your workout. And it just might save you some grief by keeping cramps at bay.
When choosing a sports drink, though, keep in mind that many can be laden with sugar that won’t be necessary for a typical hourlong gym workout. If you’re running an ultramarathon, that’s another story, but for an average day, stick to something with electrolytes that doesn’t have tons of added sugar and the extra calories that come with it.