At first blush, this seems like a problem…

Dear Lucy: I have recently taken up running again after some time off and am again wondering about a problem that I’ve had for years. I run maybe three miles at a comfortable pace on a treadmill about three or four times a week. After a run, my face turns bright red for an hour or so. I’m not particularly red when I’m running, only when I stop. Someone told me that I’m a “red sweater.” Should I be concerned that this indicates a physiological problem? —Rosy Runner

Dear Rosy: Lucy applauds your commitment to good health and exercise! For an answer to your question, she turned to MIT Medical dermatologist Allison Larson, who hastened to calm your fears. “Turning red after (or during) exercise is normal and common,” Larson assures Lucy. 

Sweating is one way the body cools itself, Larson continues. “Another way is by dilating—or expanding—the small blood vessels of the skin.” On the face, she explains, these blood vessels are very close to the surface, and when they are dilated, the face appears red. How flushed one appears after exercise is highly individual, however. “These blood vessels tend to be more obvious in light-skinned people,” Larson says, “and some people’s blood vessels dilate more easily and stay dilated for a longer time.”

Lucy hopes this explanation has put your fears to rest. She encourages you to continue working up a sweat—and a blush—and to wear that post-run red face as a badge of honor. —Lucy

Back to Ask Lucy Information contained in Ask Lucy is intended solely for general educational purposes and is not intended as professional medical advice related to individual situations. Always obtain the advice of a qualified healthcare professional if you need medical diagnosis, advice, or treatment. Never disregard medical advice you have received, nor delay getting such advice, because of something you read in this column.