READ MORE:* Michael Phelps' purple spots are caused by cupping* Michael Phelps and me: The secrets of cupping* Sonny Bill Williams undergoes hijama cupping therapyCupping - where glass cups are either pumped with air or heated inside by a flame and then applied to the skin to improve blood flow, promoting healing and muscle recovery - is proving particularly popular with the US team (the bruises were clear on gymnast Alex Naddour and swimmer Natalie Coughlin), but the technique has been used by Chinese Olympians for years. If people are considering cupping therapy, they should seek medical advice first." For the Olympians, of course, even if cupping does work purely by placebo, that mental boost could be enough to give them the crucial "marginal gain" against their opponents. "You'll probably get more people believing in cupping now because Michael Phelps has been using it - despite the lack of evidence in athletic populations." The bruises were left by cupping, a traditional Chinese acupuncture technique that has taken this summer's Olympics by storm.

Source: Stuff August 10, 2016 22:01 UTC