Why Michael Phelps & Other Swimmers are Covered in Those Weird Bruises

Michael Phelps won his 19th Olympic gold medal on Sunday night, when the United States soared to victory in the 4x100 relay. However, Phelps' appearance -- namely, the giant red circles all over his back and shoulder -- might have left you scratching your head. Turns out they're not as strange as they look. 

In addition to Phelps, several Team USA athletes have appeared at the Rio games sporting the somewhat unsightly spots -- all thanks to an ancient Chinese healing technique that's apparently become incredibly popular among some of the Olympians. 

As explained in a report by The New York Times, the practice is called cupping, and just as its name suggests, it involves placing circular cups on the skin and using heat (or an air pump) to create enough suction to pull the skin away from muscles below. And while the process lasts for only a few minutes, it creates enough suction to leave those deep purple bruises that look more like the results of a fist fight than an Olympic event. And yes, it's the same thing that happens when you give/receive a hickey. 

With that said, why the hell would anyone want to do that to themselves/look like that? The answer is pretty simple: the cupping technique is believed to reduce soreness and speed up the healing process of overworked muscles by causing a rush of blood to the affected -- and cupped -- area, per the report. The Times also points out, though, that there's not a lot of actual science on whether cupping truly helps to heal the muscles or if it's just some sort of placebo effect. Either way, it looks pretty damn weird. And painful.

But when medals, world records, and international sports glory are on the line, a few deep purple bruises are a small price to pay. Especially when you can cover them up with gold medals later.

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