Swimmer Michael Phelps is making news. And the headlines aren't just about his gold medal performance Sunday night in the 400-meter freestyle relay at the Rio Olympics.
He's also being talked about for the perfectly circular eggplant-colored bruises on his upper back and shoulders.
Phelps isn't the only Olympian sporting the discolorations - the U.S. men's gymnastics team, including gymnast Alex Naddour, also appeared to have been crop circled.
"It looks like we get attacked by octopuses," said three-time U.S. Olympian Dana Vollmer, fresh off a bronze medal in the 100 butterfly.
Naturally, it prompted a social media frenzy with photos and speculation - just what do our athletes do in their spare time?
I knew right away what the unusual pattern meant - they'd been cupped.
What is cupping?
Cupping is an ancient Chinese method that involves suctioning skin and tissue up into what is usually a glass cup that slightly resembles a light bulb. There are two methods to do this. One involves putting heat into the cup, such as a burning cotton ball soaked in alcohol, removing it, then quickly pressing the cup onto the skin. In the other method, the cup is placed on the body and the air is sucked out with a pump.
This process is said to move the qi (often spelled as chi and known as prana in yoga), also known as the life force, through the energetic channels of the body. The Chinese believe a pain that is pinpointed is a result of blood stagnation and poor circulation. Cupping helps move that blood stagnation and promote a healthy flow of qi.
Shelly Greene is a local acupuncturist who is certified in Oriental Medicine by the National Commission for the Certification of Acupuncturists. She owns Peaceful Points, where she uses cupping therapy in addition to acupuncture. She mostly uses cupping for back pain in adults, and usually in conjunction with an acupuncture treatment. She mostly places the cups on a patient's back where it's "nice and meaty," she said. Occasionally she'll do it on arms and legs, but never directly on bones or arteries. Digestive issues can also be treated with cups on the belly.
Greene also treats children, mostly for breathing and congestion problems. Parents often ask her to write notes for the kids' schools due to the one, not-insignificant side effect of cupping - the giant bruise. It could lead to the impression the kids are being beaten at home, she said.
Does it work?
Experts are divided on the matter. But U.S. swimmers seem to be sold, at least.
Phelps talked about his use of the therapy during a March appearance at the Under Armour headquarters in Baltimore. He said he and his training partners like to compete over who has the worst cupping bruises.
Western doctors and researchers tend to be skeptical about the benefits of the treatment.
"Reports of successful treatment with cupping are mainly anecdotal rather than from research studies," according to the American Cancer Society as excerpted on WebMD.
But Phelps and his longtime conditioning coach, Keenan Robinson, and other Olympians are believers.
"So if you get hit really hard and you bruise, it's not that kind of bruise," Cody Miller, bronze medalist in the 100-meter backstroke, said. "Your muscle tissue isn't torn up in there. It's just pulling blood into a specific area, and then it just kind of sits there as that tension builds and then you release that tension.
I got cupped. Greene gave me a tiny taste of the therapy, having me lie face down on her massage table. You'll remain clothed, though depending on where the cups are being placed, you might need to bare your back. She placed two cups on the middle of my back, one at a time, sucking the air out with a pump. My skin and the underlying tissue filled up the glass dome which I was only able to see because she kindly took a photo with her cell phone. It's slightly disconcerting to see. I didn't realize my skin could contort like that. It was pain-free and felt a little like I was getting plunged with a toilet plunger. In a much more pleasant way. Others have described it as being hugged, or attacked, by a giant octopus.
Sometimes oil is rubbed into the area and the cups are then moved up and down the long muscles in the back. Greene demonstrated on me and it felt like a nice, strong massage.
Cups are generally left on around 10 minutes or so, depending on the patient. Mine were only left on for a minute or two and didn't leave any telltale marks when I checked in the mirror an hour later.
The treatment is usually described as deeply relaxing and enjoyable, with no adverse effects. However, Greene said, it's not recommended for those with open lesions or bleeding disorders.
The Washington Post and Tribune News Services contributed to this story.