Why Are Michael Phelps And Other Olympians Cupping?

This is why Michael Phelps has strange purple circles all over his body.

Last night, during 19-time gold medalist Michael Phelps’ 2016 Olympic debut, he removed his jacket, revealing a series of purple circles all over his body. Immediately, the Internet rushed to WebMD to see if America’s greatest Olympian had the Zika virus or a received a rash of hickeys after a round of pre-Olympic canoodling.

If you were one of the concerned, have no fear, our hero along with fellow swimmer Natalie Coughlin and gymnast Alex Naaour have actually been undergoing an ancient Chinese treatment known as cupping. During the therapy, small circular cups placed against the skin are pressurized using heat or an air pump which pulls on the skin. The pressure ruptures capillaries in the skin which causes bruising. The procedure is said to increase blood flow to muscles to hasten their recovery time.

Although the results look a little odd, according to Phelps’ trainer, there’s no need to be alarmed. “Because this particular recovery modality shows blemishes on his skin, he walks around and looks like a Dalmation or a really bad tattoo sleeve,” Keenan Robinson told The New York Times. “It’s just another recovery modality. There’s nothing really particularly special about it.”

Here’s a Phelps undergoing the procedure about a year ago:

via Instagram