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Exercise that makes you sweat can lead to muscle cramps, especially if you’re working out in hot weather. And drinking plain water can make things worse. In fact, plain water increases the odds of cramps developing during or after the activity, because the water dilutes the electrolytes in your body instead of replacing them.
That’s what researchers at Australia’s Edith Cowan University found in a study of 10 men who went for hot-weather runs lasting 40–60 minutes. The lesson: electrolyte depletion is a bigger problem than dehydration.
The solution: Add electrolytes, including sodium, magnesium, and potassium, to your water when you’re doing physical activity that makes you sweat. And drink that mineral-spiked water after the workout as well.