If you've been watching the Olympics lately and wondering what those purple spots were on Michael Phelps' back and shoulders, you’re not alone.
It's actually the result of a not-so-new therapy called cupping, a Chinese alternative medicine that has been around for thousands of years.
"I think he's doing it more for sports and the muscles and the strain and the stress on the joints and the muscles to help improve for the next swim," longtime cupping client Tom Sroczynski said.
Now that people have seen Phelps sporting these marks, they are becoming more interested in the art.
"We got a lot of phone calls right now. They ask about this ... recently," cupping therapist Dr. Rui Wang said.
Cupping uses suction to pull blood to a specific region to stimulate healing. Cupping helps the tissue develop new blood flow and reduce inflammation.
"I look at it more for inflammation, circulation, colds, or people with arthritis and other ailments would use the cupping," Sroczynski said.
It is partially used as therapy and partially as a diagnostic tool. The varying degrees of darkness in the circles guide diagnosis, because it shows where there is more inflammation.
"Normally, it's always in the back and the shoulder area, and she does them on the meridian points," Sroczynski said.
In Chinese medicine, a meridian is known as an "energy highway" in the human body. So those areas are targeted in an attempt to open those channels.
The sensation of cupping can be compared to sticking your hand to the end of a vacuum hose, so don't let the dark marks fool you.