As millions of fans around the world tune in to watch the Olympic Games, many have noticed a strange, recurring sight—dark red circular marks on the bodies of athletes. Whether it’s on their shoulders, backs, or even legs, these peculiar circles have sparked curiosity and left many wondering: what are they, and why do so many top athletes have them?

This phenomenon was particularly noticeable during the 2024 Paris Games, where more than 6,800 athletes from 205 countries competed. For many spectators, these marks were a familiar sight, especially those who remembered the 2016 Rio Olympics. Swimmer Michael Phelps didn’t just capture attention for his record-breaking gold medals, but also for the prominent red circles covering his back and shoulders.

So, what’s the deal with these mysterious marks?

The answer lies in an ancient recovery technique that’s recently found popularity among elite athletes: cupping therapy. These marks aren’t bruises or injuries—they’re the result of this time-honored practice, which has been around for over 2,000 years, originating from traditional Chinese medicine.

What Is Cupping Therapy?

Cupping therapy involves placing special cups on the skin, where a suction effect is created either by heat or air. The suction pulls the skin upward, which increases blood flow to the affected areas. This process often leaves behind the distinctive red or purple marks, which can last for several days.

But don’t be alarmed—these marks are not painful, and many athletes claim the therapy helps with muscle recovery, reduces pain, and even relieves inflammation. For athletes putting their bodies through the extreme physical demands of Olympic-level training and competition, any edge they can get for recovery is invaluable.

While the science behind how exactly cupping works isn’t fully understood, its growing popularity among athletes speaks for itself. Top competitors, from swimmers and gymnasts to NBA players, swear by the benefits of cupping. They say it helps them recover faster after grueling training sessions and intense competitions, allowing them to get back to peak performance more quickly.