Not for their muscles, but maybe for their minds.

If you've been watching the Olympics (or a bunch of other sports), you've probably seen some athletes wearing tape on various parts of their bodies. I first noticed some of the Chinese divers with tape on their lower backs. Other athletes have it on their shoulders or legs. What is this stuff? And how does it work? Actually, let's step back: Does it work?

It's called kinesio (or just 'k') tape. Athletes use the tape as a kind of elastic brace that they say helps relieve pain. The tape and technique were developed by Kenso Kase thirty years ago in Japan. Since then, many companies have developed similar adhesive tapes and they are in something of a marketing war.

Unfortunately, the evidence that k tape does much of anything is scant. One positive and relatively sophisticated trial found some shoulder pain relief in using the tape. But that study had some serious methodological problems. A metareview published earlier this year of all the available studies on the use of the tape was less positive. It looked at 97 papers on k-tape focusing on 10 studies that actually had control groups. Here's what they found:

In conclusion, there was little quality evidence to support the use of KT over other types of elastic taping in the management or prevention of sports injuries.

The tape, they continued, "may have a small beneficial role" for some injured people in certain situations, but "further studies are needed to confirm these findings."