They've been hard to miss at this year's Olympic Games: Strips of brightly colored tape adorning the arms, legs, and torsos of many top athletes. But more than just fashion is driving this trend.
The tape is called Kinesio tape. Many athletes believe it has medical benefits.
The tape was invented by Japanese chiropractor Kenzo Kase in the 1970s. The U.K. web site for Kinesio tape claims it can alleviate pain, reduce inflammation, relax muscles, enhance performance, and help with rehabilitation as well as supporting muscles during a sporting event.
There has not been conclusive scientific or medical evidence to confirm the effectiveness of the tape. A review of evidence from 10 research papers for Kinesio tape to treat and prevent sports injuries was published in the journal Sports Medicine in February.
- No clinically important results were found to support the tape's use for pain relief.
- There were inconsistent range-of-motion results.
- Seven outcomes relating to strength were beneficial.
- The tape had some substantial effects on muscle activity, but it was not clear whether these changes were beneficial or harmful.
The study concluded there was little quality evidence to support the use of Kinesio tape over other types of elastic taping to manage or prevent sports injuries.
Some experts have suggested there may be a placebo effect in using the tape, with athletes believing it will be helpful.
"The jury is still out on the hard and fast science of it," says John Brewer, head of sport and exercise sciences and director of sport at the University of Bedfordshire in the U.K.
He finds it difficult to understand how the tape can help: "When we exercise, it is muscles that are deep down in the body that are as much part of the energy-generating process as muscles near the skin.
"I'm still struggling to come to terms with how tape that is placed on skin can have any real, major effect on performance, other than potentially, a psychological effect."
He says the tape may help as part of an athlete's personal habits in preparation for an event: "The actual putting on of the tape sometimes is almost part of that ritual. It's almost part of their uniform for the sport that they're doing, part of their kit. It makes them feel ready for action."
Brewer says if athletes think the tape will help support their muscles, then that can boost their confidence. "I think if you can get somebody in the right frame of mind, then that can make a big difference on what they do.
"But for me, there isn't any firm evidence yet to suggest the tape really does work, other than the anecdotal evidence from some athletes who say: 'Yes, it works for us.'"
Philip Newton, physiotherapist and director of Lilleshall Sports Injury Rehab, agrees the benefits may be in the mind: "My view is that Kinesio tape probably has a significant placebo effect," he says in an email. "The placebo effect is not fully understood but it is generally accepted that any treatment/intervention will elicit a placebo response, which has complex cultural and contextual elements."
He says the design helps, too: "I believe that part of the genius behind the phenomenal commercial success of Kinesio taping was the idea to manufacture it in highly visible colors. This is in contrast to the traditional colors used for traditional types of tape/bandage.
"Many sports performers have historically chosen to hide any strapped areas of their bodies so as not to advertise any areas of potential physical weakness. In stark contrast, many contemporary sports people do exactly the opposite with Kinesio tape. It seems that for many it is a badge of honor.
"Maybe some wear it as a means of explaining away any possible future failures or defeats? Or maybe they want to demonstrate that they have the grit and determination to push through the adversity of injury."
Kinesio Taping by Physiotherapists
Gavin Daglish is a physiotherapist at Mike Varney Physiotherapy in Harlow, Essex, U.K. How effective does he find Kinesio tape? "Really, really effective," he says. "I've found it to give, not instant, but over the next 24-48 hours, to give fairly good pain relief."
It's not just athletes he's used the tape on: "I've used it on a 45-year-old builder who's got lower back pain. It's actually quite effective with it.
"I've also found it effective on a 16-year-old with anterior knee pain because he does a lot of sport. That's been really effective."
How does he think it works? "It was designed to run with the contours of the skin," Gavin says. "It allows free movement of lymphatic fluid. It reduces friction between the tissues in the skin.
Can people put it on themselves? "Generally you need someone qualified," he says, but a physiotherapist can teach athletes how to tape themselves.
Jeremy Parker is a physiotherapist at Six Physio in Central London. "I get great results with it," he says.
He admits the way the tape works hasn't been fully shown by research, however: "The elasticity of it lifts the skin very slightly to allow a little bit better circulation through."
He's used it to tone muscles down, to take some of the tension out of the muscle, as well as in ways designed to stimulate affected areas.
Do athletes feel the tape is there? "It's a very subtle thing," Parker says. "Because the tape is so elastic, it moves with you." The feeling is different to traditional taping, he says: "The athlete can move naturally without this constant feeling that something's pulling them in a certain way."