As tight as they are bright, compression socks, sleeves, shorts, and pants promise to boost performance and recovery. But scientists aren’t entirely sure how—or if—compression gear works as advertised, questioning its usefulness in competition and recovery. We might be better off, they say, lounging around in compression than we are racing in it.
There is moderate evidence to support wearing compression gear after a long race or workout. Jessica Hill, a sports scientist at St. Mary’s University in Twickenham, England, tested the gear’s effect on recovery in two groups of marathoners. When asked to hold a squat the day after the marathon—a formidable task—those who immediately and continuously donned compression leggings post-race (removing them only to shower) reported less quadriceps soreness compared to those in the control group. Hill also reviewed 12 studies examining compression gear and recovery. The resulting data showed compression gear provided a modest reduction in soreness and muscle damage while restoring both leg strength and power, possibly by reducing inflammation. “For an athlete who needs to do lots of training programmed quite closely together that could be an advantage,” Hill says. For others, “The only benefit they’re likely to get out of it is probably reduced soreness.”
But scientists are beginning to ask if minimizing inflammation is desirable goal, particularly in the middle of training; inflammation may be what forces muscles and bodies to build back stronger. “If we are reducing the inflammatory response, are we reducing an adaptive response of the body?” asks Hill. “Nobody really knows for sure at the moment.”
Scientists also don’t know exactly how compression garments work. One idea is that a pump in the calf muscle, which shoots blood up to the heart with each contraction, is amplified by the extra squeeze of compression socks. Augmenting the calf muscle pump in this way could improve circulation, delivering more oxygen-rich blood to needy muscles, potentially boosting performance.
Yet there is little to no evidence that it does actually improve performance during a race. Juan del Coso Garrigos, an exercise physiologist at Camilo José Cela University in Madrid, studied marathon and half-Ironman participants and found no difference in finish time fatigue, muscle damage, or muscle pain, between those who raced in compression socks and those who wore regular socks.
Del Coso thinks any supposed benefits are from the placebo effect. Despite telling study participants about his results, many say they will continue to wear the gear during the race. Except for hot days, though, when the extra cover-up can contribute to overheating and dehydration, he doesn’t see any harm in doing so. If looking like an elite makes you feel like one, go for it, he says.
Hill disagrees with that advice. She can’t entirely rule out a placebo effect in her recovery study and says she wouldn’t recommend wearing compression garments if she discovered their effects were only mental. She warns, “If people are returning to training feeling mentally recovered but they’re not physiologically recovered, they’re probably putting themselves at more risk of injury.”
So save the bright and binding clothes for after your peak race. If they do improve circulation, as researchers suspect, they may help clear out metabolites—chemical products of metabolism that accumulate when working out that contribute to soreness—possibly quickening recovery. Indeed, many wearers report that compression gear reduces next day aches and pains, known as Delayed Onset Muscle Soreness (DOMS). It may be a psychological mind-trick, but if it puts a little bounce in your post-race shuffle, it might be worth it. Just don’t return to your normal training and racing routine until you feel fresh, sans socks.