Acne Not Triggered by Exercise: Study

Exercise and sweating do not increase acne, contrary to popular myth, according to Stanford University School of Medicine researchers.

Their single-blinded study found that changes in acne did not correlate with the days exercised, time spent exercising, time sweating during exercise, or the time between exercise and showering, the researchers reported.

"It's okay for people with acne to go ahead and exercise and take a shower within the hour," said Dr. Alexa Kimball, MD, PhD, director of clinical trials at Massachusetts General Hospital in Boston.

The study dispels a long-held myth among patients and some physicians that strenuous exercise producing sweat can actually worsen acne.
In an earlier study of football players, researchers coined the phrase "acne mechanica" after discovering a variant of acne vulgaris that occurred in the areas where the helmet or uniform padding rubbed the body.

That study left many patients and physicians with the perception that exercise producing sweat could worsen acne, said Dr. Kimball.

"Looking at football, the sport did worsen acne, but mainly from a frictional component from mechanical forces on the skin," she said.

"There were concerns that the athletes' acne would worsen when they were sweating and dirty."

During the study, there were no statistically significant changes in acne among the three groups of men. Changes in acne did not correlate to the number of days exercised, time spent exercising, time of sweating during exercise, nor the time interval between exercising and taking a shower. Stress levels were similar among the three groups of men.

Dr. Kimball said that while the men who showered within an hour of exercising had many more lesions than men who delayed showering "this was not statistically significant."

Guy Webster, MD, moderator of the acne poster discussion session and vice chairman of dermatology at Jefferson Medical College in Philadelphia, Pennsylvania, said the study did not address acne mechanica, which can seriously disrupt the skin with athletic equipment. But he agreed with Dr. Kimball's premise about misinformation and acne.

"There are a zillion different misconceptions about acne," he said.

Two of those misconceptions are that both diet and dirt have something to do with acne outbreaks, Dr. Webster said.

"This study shows that the dirt you generate yourself — the dirt and grease on the skin — doesn't have much to do with acne."