Purple circles on Michael Phelps' shoulder are a sign of cupping therapy. https://t.co/ZmABa3lyV6 pic.twitter.com/7uMytNlfen — Good Morning America (@GMA) August 8, 2016

RALEIGH, N.C. (WTVD) -- Cupping, which causes those red circular spots on Olympic athletes, is becoming a household word thanks to the Summer Games in Rio.But it's old news to NC State athletes, who have been using cupping for two years during competitions and at this year's Olympics qualifiers.Olympic athletes from all over the world, including the most-decorated, Michael Phelps, have been spotted with red circular impressions on their skin during the Games -- a result of cupping, a therapeutic treatment that uses suction to massage tissue.The Wolfpack swimming and diving team has a licensed, nationally certified massage therapist that uses the cupping technique and travels with the team during ACC and NCAA championships - and now most recently, to the Olympic qualifier in Omaha, Neb.Christina Longobardi-Paradiso is that massage therapist, and she's been with the Wolfpack team for five years, and using the cupping technique for the past two.(Longobardi-Paradiso with Team USA gold medalist and NC State junior, Ryan Held, at the 2016 Olympic qualifier.)While the benefits of cupping therapy have been, Longobardi-Paradiso said the technique helps athletes with muscle relief in between races during competition."If you think about it, when you're doing a race like a freestyle or a fly and you're using your shoulders, in particular we see that a lot on the shoulders and back, the fact that it's so tight ... it's like the muscle is Saran wrapped," Longobardi-Paradiso said."In between meets or in between an event, which might only be like a two-hour or a six-hour break between an event, or maybe even a twenty-minute break if they have to do one event and then another -- the suction is a really, really easy way to pull up that inflammation and all that tightness that's in the tissue and the muscle," she added.In addition to cupping, Longobardi-Paradiso said she also uses techniques such as Thai yoga massage, where she uses the weight of her body for deep tissue massage, as well as other techniques to figure out what's best for each athlete.Rising sophomore Justin Ress is on the team and swims freestyle, backstroke and 90M. He's used cupping therapy with the team and said he feels it made a difference in recovering from muscle pain."It's basically an intense, really concentrated massage on one area where the cup is," Ress said. "While it's going on it feels really weird, and it looks really weird, but after it feels like lactic acid has literally been lifted from the muscle; pretty cool."It definitely does make your legs, or whatever area's targeted, it makes them feel better and more loose and ready to do intense physical exercise, so I think it definitely helps," he added.