People who are overweight seem to sweat more than svelte athletes — but that's not entirely because of body fat. A new study explains why losing weight might not affect your sweat rate the way you'd think.
Photo by Kullez.
The amount you sweat depends on how much heat your body generates, because the purpose of sweat is to cool you down. Body size is a big part of that, since the bigger you are, the more work you do and thus the more heat you generate. Until recently, there was a hypothesis that body fat insulates you, keeping your body warm. But according to a study published in the Journal of Applied Physiology, fat only accounts for 1.3 per cent of the variation in people's sweat rates.
That means that if you lose fat but gain muscle, staying roughly the same size, that won't change your sweat rate very much. If you do lose a lot of fat without replacing it, you'll end up sweating less — because you're a smaller person, and have less weight to haul around.
What Determines How Much You Sweat? [Runner's World]