Compression clothing is one of the latest trends to hit the sports and fitness scene. Compression clothes hug the body tightly—the theory is that they assist with blood flow by squeezing the muscles almost as a massage would. It’s thought that this reduces fatigue and soreness after exercise. Other claims surrounding the utility of compression clothes include that they increase the ability to sense how one’s body is positioned in space (known as proprioception), and that they help with oxygen delivery for enhanced sports performance.

Unfortunately, as cool as this all sounds, and despite the fact that some enthusiasts swear by these clothes, the science is mixed when it comes to backing up the hype. A new study published this month found that compression clothes did not increase maximal oxygen uptake or beneficially alter running mechanics in 16 trained, distance runners. Another study from 2013 measured whether compression clothes increased blood flow to leg muscles post-exercise—and found that they did not. At the same time, however, a review of more than 30 studies did find small or moderately beneficial effects from compression clothing on a number of fitness metrics, including extending time to exhaustion, time-trial performance, and a reduction in muscle swelling and perceived muscle pain during recovery. One problem with doing research on compression clothing is that the study participants cannot be blinded—that is, they know whether they are wearing the clothing, which may contribute to increased performance in the form of a placebo-effect. Partly for this reason, it could be a while until science can finally unravel whether the claimed benefits are real. In the meantime, since there don’t appear to be serious side effects from wearing compression clothes, people can experiment with them without too much concern.

Source: New York Times