ALL IN YOUR MIND:

A review of more than 30 studies of the effects of compression clothing in sports performance and recovery, for instance, determined that "compression clothing may assist athletic performance and recovery in given situations." Those situations involve sports such as basketball or track and field that require explosive sprinting and leaping, although athletes in other sports, including weight training, have reported feeling less sore if they wear compression clothes than if they don't, the review found.

How the clothes work, though, remains mostly baffling -- and may owe something to input from the mind. "We can't blind people" in exercise studies about whether they are wearing compression garments or not, said Billy Sperlich, a professor of exercise science at the University of Würzburg in Germany, who led the study of blood flow and also was a co-author of the recent review.

So people's expectations of what the clothes will accomplish may color their results.

Which does not mean that any resulting benefits are not real, Dr. Sperlich said. "Since beliefs are strong performance enhancers, I would recommend compression clothing to persons who believe in the performance-enhancing effect," he said.

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