Team USA swimmers and gymnasts are particularly keen on the healing trend -- known as cupping -- including Olympic megastar Michael Phelps, who looks to almost be collecting more circles on his shoulders and back than he has won in gold medals!
How the procedure works is by lighting a small fire within round glass cups. When the flame goes out, the cups are applied to sore parts of the body. The drop in temperature causes a suction effect that pulls at the skin and promotes blood flow -- leaving the round splotches, which can last a few days.
And let's not forget, that as with just about any alternative health trend, Gwyneth Paltrow has not only done it, but did so before it even became a thing. Case in point? The Oscar winner was seen with the spots at the NYC premiere of Anchorman -- in 2004.