Runners decked out in compression gear may seem intimidating when they speed by you in the park, but their attire may be more for show than performance.
At the annual American College of Sports Medicine conference in Denver, Colorado, on June 1, researchers from Ohio State University presented results from a study that showed compression tights don’t reduce fatigue at all. Although the work hasn’t been published yet in a peer-reviewed journal, the abstracts were approved by conference organizers ahead of time. Their work was funded by Nike.
Athletic gear companies have promoted the benefits of such ultra-tight clothing for years, saying that they “deliver increased power and stamina” or ”focus your muscles’ energy to generate maximum explosive power, acceleration and long-term endurance,” as Deadspin reports. And consumers have flocked to them: sales of compression and other form-shaping gear are expected to reach $5.6 billion by 2022.
For the study, the researchers had 20 experienced male runners run on a treadmill for 30 minutes at 80% of their maximum effort (each runner estimated this speed for himself). Each runner did this on three separate days, once with just shorts, once with light compression pants, and once with slightly tighter compression pants. Before and after each run, runners were asked to complete a series of jumping and weightlifting tests to assess their overall fatigue. The results? “We didn’t see any associated difference in how tired they were,” says Ajit Chaudhari, a biomechanical engineer at Ohio State University and lead author of the paper.
The research was trying to assess the validity of the claim that muscle vibrations—the jiggling that occurs when a runner’s foot hits the ground—may eventually (paywall) lead to weakness over time. By using high-speed cameras to observe the runners’ legs as they struck the ground, the researchers did find compression gear reduces muscle jiggling, but less vibration had no improvement on fatigue.
Other studies have debunked the supposed performance benefits of compression tights, but they still may have some effect on recovery. Even here, though, the research is extremely limited and recorded improvement small. In a 2012 randomized trial (paywall) from researchers in New Zealand, 14 cyclists biked 40 km (25 miles) one day and were given either spandex or compression tights to wear the next day. Bikers didn’t know which fabric they were given. The following day, they biked another 40 km. The next week, bikers did the same test, but were given the opposite material during their recovery period. The authors reported a slight increase in performance; bikers who had recovered in compression gear were on average 1.2% faster. Notably, the cyclists were wearing compression gear after they finished their workout, not during.
That said, there could be a benefit to less jiggling while running. “When you get to somebody who has a little bit of heavier build, the vibration may make them actually uncomfortable,” Chaudhari says. “For that person, the compression seems like a good idea.”