What is cupping and why do Michael Phelps and other Olympians have round blotches on their skin? For those unfamiliar with it, cupping has been around for centuries, and has been used to relieve muscular soreness and improve mobility. In Europe, cupping had been used and some people had sets of these cups that were applied to the skin to create negative pressure and offer pain relief. In Asia, fire cupping therapy was used that did something similar and today, cups that have an ability to suction using a device that attaches to the top of the cup is used. The third method, suction cups is what athletes like Phelps are using to get the effect of pain relief and improved mobility. According to CNN "The therapy consists of having round glass suction cups that are warmed, then placed on sore parts of the body. The placement of the glass cup creates a partial vacuum, which is believed to stimulate muscles and blood flow, while relieving pain." Four years ago, everyone had proprioceptive tape, which helped many athletes compete and avoid injury, while others just used it because it was popular and freely available. Apparently, cupping is this years flavor du jour for Olympic athletes. How effective is it? That depends on whom you are talking with, however, part of the success athletes have is a mental game, and if they feel a method gives them an athletic edge and they feel confident by using it, they are likely to perform better. Athletes can be superstitious, so anything that gives them a physical edge in competition is something they will use to help them perform their best. Read more about this interesting therapy Olympics in bright red spots: What is cupping? By Madison Park, CNN Tue August 9, 2016 Those dark red spots dotting Olympians' shoulders and backs are not cigar burns. They're not perfectly circular hickeys either. Viewers watching the Olympics this weekend may have spotted the pepperoni-like bruises on athletes and wondered: What is that? Olympians at Rio have taken to cupping -- an ancient therapy that have mostly been used in Middle Eastern and Asian countries, especially China. The therapy consists of having round glass suction cups that are warmed, then placed on sore parts of the body. The placement of the glass cup creates a partial vacuum, which is believed to stimulate muscles and blood flow, while relieving pain. Michael Phelps, US gymnast Alex Naddour and Belarus swimmer Pavel Sankovich have all posted pictures of their polka dotted limbs and backs. Sankovich wrote earlier this summer on his Instagram account: "Cupping is a great recovery tool," with a photo of his thighs covered in suction cups. Former Olympic swimmer Natalie Coughlin has also previously posted pictures of herself going through a cupping therapy. Phelps showed snippets of his cupping therapy on his Instagram as well as his Under Armour commercial. Read more