Breaking a sweat might spark a surprising urge—the one to scratch your itchy skin.
Itchy skin is actually a pretty common response to exercise, says Dr. Michael J. Ryan, associate professor of exercise science at Fairmont State University.
When you get moving, your heart pumps more blood to your working muscles, like your thighs while running, or your chest while bench pressing. This fills millions of capillaries.
“As the capillaries expand, they push outward, stimulating surrounding nerve cells, which in turn sends signals back to your brain,” explains Ryan.
The result? Your brain translates these signals as an itch and you’ll find yourself with itchy skin.
The only thing you can do to lessen the itch is to maintain a workout routine. If you exercise regularly, your brain gets accustomed to the signals and starts to ignore them.
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But the longer the break you take from the gym, the more intense the itch will be when you return, says Ryan.
If your itching comes with welts, hives, or a feeling of faintness, call your doctor. This could be a more serious case called exercise-induced urticaria.