grabbed fans’ attention at his fifth
by earning his 19th gold medal – but he also caught their attention for the strange purple bruises on his body.
The round bruises are the end product of a healing technique called cupping, and Phelps isn’t the only athlete trying it. American gymnast
recently posted an Instagram picture of himself with a cupping mark clearly in view, and former Olympic swimmer
has sported the purple dots on her body.
“That’s been the secret that I have had through this year that keeps me healthy,” Naddour told
about the therapy. “It’s been better than any money I’ve spent on anything else.”
Cupping involves heating small glass cups, then placing them on the skin and pulling them from the body to loosen and relax muscles. The resulting bruises last about two weeks.
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AP Photo / Lee Jin-man
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Does Michael Phelps Already Have a Future Olympic Swimmer on His Hands?!
The alternative medical treatment may be all the rage in Rio, but it’s hardly the first time the practice has made headlines.
at a movie premiere in 2013.
have also tried the ancient technique.
Although modern science has not been able to confirm the benefits beyond a placebo effect, according to
Business Insider‘s Rebecca Harrington
, athletes swear by it.
“Our bodies are going to hurt after doing this for so long,” Naddour said. “It’s the best thing that I’ve ever had. It has saved me from a lot of pain.”
And given that Phelps took home his 23rd Olympic medal last night, it’s tough to argue.
To learn more about all Olympic hopefuls, visit teamusa.org. The Rio Olympics begin Friday on NBC.