There are a number of culprits, right here. First up: Whenever you train, your coronary heart pumps extra blood to your exhausting working muscular tissues. This momentum then causes your capillaries to expand, and as they achieve this, they stimulate the encompassing nerve cells in your physique—and your mind interprets that sign as an itch. “It is a extra doubtless state of affairs for the physique versus the face,” says board-certified dermatologist Deanne Mraz Robinson, M.D., FAAD, co-founder of Modern Dermatology and assistant medical professor of dermatology at Yale New Haven Hospital, (since your bigger muscle teams are powering the toughest, and thus require extra blood move), “However the identical science applies.”
Or, when you’re vulnerable to flushing while working out, itch can definitely observe. “Train results in dilation of your blood vessels to reinforce circulation to your pores and skin and muscular tissues,” says board-certified dermatologist Joshua Zeichner, M.D. That is typically a great factor—in spite of everything, it’s elevated circulation that delivers vitamins to the cells and lends the beloved “post-workout glow.” However for some folks (particularly these with honest to medium pores and skin tones, delicate pores and skin, or situations like rosacea), it might result in irritation, which can lead to flushing, bumps, and, sure, itching.
In some instances, that prickly sensation may signify a sort of warmth rash, known as miliaria rubra. “It is a situation the place there are blockages throughout the sweat glands, resulting in tiny, purple bumps and a prickly or itchy feeling,” says Zeichner. “This develops when sweat is trapped within the glands due to points like non-breathable, moist exercise clothes sticking to the pores and skin.” It’s additionally rather more frequent in scorching, humid climate—say, when you’re jogging exterior noon within the throes of summer season.
And, lastly, folks can simply react to their very own sweat. Whereas sweat can effectively clear pores, some people could also be hypersensitive to its contents. “Moisture, warmth, and sweat can all trigger irritation of the pores and skin,” says Mraz Robinson. Easy as that.