The Most Common Sports Injury? : Specialist Says Skin Bears the Brunt of Punishment

Broken bones and strained muscles may worry athletes but the more common sports injuries are skin problems such as “black heel,” “bikini bottom,” “jogger’s nipples” and “runner’s rump,” a physician reports.

Dr. Rodney S. W. Basler, an assistant professor at the University of Nebraska Medical Center and a specialist in sports medicine, said the skin “bears the brunt of the punishment” from vigorous exercise and can develop injuries in unexpected ways.

“The percentage of people in fitness conditioning or good athletic programs who develop some types of skin problems is quite large,” Basler said in an interview at the recent American Academy of Dermatology meeting.

Most of the skin injuries will go away when the exercise is halted, and few pose a continuing problem, Basler said. But the injuries can cause irritation, pain and cosmetic concern.

Joggers and marathoners, whose skin must endure hours of punishment, are heir to a number of dermatological problems ranging from black heel to runner’s rump.

Black heel develops when constant flexing of the foot causes two layers of the skin, the dermis and the epidermis, to rub against each other in a shearing force, Basler said. This breaks small blood vessels and causes blood to pool between the skin layers, usually at the heel. The result is blackened skin.

He said black heel will correct itself when the activity stops, but many patients seek treatment because they worry about cancer.

“Runner’s rump” is a discoloration at the base of the spine, where the buttocks come together. The doctor said it is a pigmentation change caused by the friction of the buttocks rubbing against each other. The only concern, Basler said, is cosmetic.

“Jogger’s nipples” is a more painful problem, usually experienced by men; usually runners who wear shirts that are rough. The friction of the cloth actually rubs the nipples raw. Few women experience the problem because they wear soft bras, he said.

“At the end of a marathon, you’ll see lots of men with blood stains on their shirt front because the nipples have been rubbed raw and are actually bleeding,” Basler said. “It’s surprising how big a problem this can be. It actually stops some people from running.”

Prevention is simple: wear a soft cotton undershirt, or cover the nipples with petroleum jelly or paper medical tape. Or run bare-chested.

Pool chemicals can cause swimmers to develop a variety of skin problems. Basler said many pools use bromide instead of chlorine to control bacteria in the water. This can lead to a form of acne called “bikini bottom,” an ailment usually consisting of acne-like pimples and nodules, most often on the backside.

“It looks very much like classic acne,” Basler said, “except it’s usually under the swimsuit.”

Treatment and prevention are both achieved by “not sitting around in wet swimsuits,” he said.

Basler said some patients who swim often also visit him because of light-colored hair that suddenly turns green. The color change is a result of copper in the pool water that “gives a real distinctive greenish tint to the hair,” he said. The treatment is to bleach the hair with peroxide.

All athletes who spend hours exercising in sweaty sneakers can develop what Basler calls “toxic sock syndrome.” The ailment is characterized by a strong foot odor and is caused by a bacterium related to acne that grows in the soft tissue of the feet. Left alone, it can cause pits to develop in the skin, he said.

Treatment is with over-the-counter acne medication containing benzoyl peroxide, and prevention is by using more absorbent socks and a foot powder.