'Very little evidence to support it': Why some scientists give cupping a poor score

Some scientific judges are giving poor scoresfor the efficacy ofcupping, a pain-relief therapy that's beendrawingattention at the Olympicsbecause of its use byathletes, including American gold medal swimmer Michael Phelps.

"Cupping is one of those things where there's very little good scientific evidence, very little good research done on it," said Timothy Caulfield, Canada Research Chair in health law and policy at the University of Alberta. "There's very little evidence to support it."

"For mepersonally I'm very veryskepticalaboutthe science of cupping," said Caulfield, author ofIs Gwyneth Paltrow Wrong About Everything?: When Celebrity Culture and Science Clash.

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Yet athletes like Phelps and U.S. gymnast AlexNaddourseem to swear by the centuries-old traditional Chinese medicinepractice, and have the purplish circle spots on their body caused bythe technique to prove it.

"I wouldn't say he was on it right away," Keenan Robinson, Phelps's longtime strength-and-conditioning coach, told Time."When he realized it would take five minutes and that this could get him from Tuesday to Thursday [workouts] and from Thursday to Saturday [workouts], he was on board."

The methoduses actual cups, glass or plastic, that are placed on the area of the bodyexperiencing pain. The glass cup can be heated while the plastic cup is attached to a pump both creating a suctionforce that draws skin up into the cup.

It's about a five- to 10-minute process that, according to cupping advocates, activates aperson's Qi, or whattraditionalChinese medicine practitioners describe as an individual'slife force.

The technique stimulates blood flow, drawingtoxins and old stagnant blood from deep within the body to the surface below the skin layers, according to the website of Dr. Mee Lain Ling, a Richmond B.C.-based practitioner of TCM.(There's also wet cupping, which includes using a needle to makeshallow pinpricks into the skin.)

Those circular welts covering the bodies of athletes who use this method are a result of the temporary bruisingcreatedby thesuction breaking the blood vessels under the skin.

'It's a supernatural idea'

"This idea we have this life force energyrunningthrough our bodies and we can use various techniques to balance or adjust or heal that lifeforceenergy it's asupernaturalidea,not onethathasanyscientificfoundation," Caulfieldsaid.

Applyingsuction to key parts of the body torestore the balance or flow of the blood andother fluids is a theory from centuries before scientistsunderstood how blood flows or how diseases are caused, saidRachel Vreeman, director of research at the Indiana University Center for Global Health.

"There is no strong scientific evidence that cupping provides pain relief,"saidVreeman, who has co-authored a number of books debunking health myths.

"Cupping basically causes a hickey, and it will go away."

Some studies seem to have shown that cupping does provide some painrelief. But Vreeman said a 2012 review of 135 studies from 1992 to 2010found they were not welldesigned and more rigorous research would be needed to recommend cupping for any of the problems they evaluate.

Trial results of 'very poor quality'

Edzard Ernst, professor of complementary medicine at the University of Exeter's Peninsula School of Medicine, said some of the most recent trials from China showing positive results are of "very poor quality,"not "worth the paper they are printed on" and are likely due to the placebo effect.

And athletes, who are totally concentrated on their body, are ideal placebo responders, he said.

"I think this is the effect they benefit from when they use cupping. I understand why athletes use it. They are not allowed to go anywhere near drugs during the Olympic Games."

But these Olympicathletes, whooccupy a big stage, may alsobelegitimizingcupping for the rest of the population, Caulfield said.

"You have these athletes that are putting everything on the line andthey're turningto thisand that's sortof a powerful endorsement, which Ithink is unfortunate."

'Important to keep an open mind'

But Ling said her clients,who includeformer professional athletes, body builders and just average people,have experienced great success with cupping

"It's really important to keep an open mind about the differentmodalitiesthathave been in use, not just for centuries, but millennia, in other cultures around the world."

"If peopleremainclosed before they know anything about it and they're notwilling to do the researchor not willing to participate in what has already been done, or toexplore it for themselves personally thenthat immediatelyshuts the door."