The theory behind cupping is that it moves or stimulates your body's natural energy — also called qi. Cupping is said to increase blood supply to a specific area, and athletes use it in recovery to help heal sore, tired muscles.
"There is no evidence pro-con that shows cupping works or does not work. This is true for a lot of mainstream ideas about warm-up and recovery. It is also true for a lot of outside-the-box ideas. There can be placebo effects for these sorts of things, and what I tell athletes is that if they think it helps and there are no downsides, then, if it feels good, do it. The key is to not try anything brand new the day of competition."
Cupping therapy involves heating the air inside a glass cup, which removes some of the air from the cup. The cup is then quickly placed on the skin, and the resulting vacuum pulls the skin partially into the cup, causing a bruise. Some people say they do experience a release in muscle tension afterwards, but there's not much research to prove one way or the other.