If you spend any amount of time on the internet, you’ve probably been a little enchanted by the bulky, full-leg compression devices like the Hyperice Normatec 3 that you’ve seen on your favorite fitness influencer or pro athlete. Are they really a magical recovery tool that will let you relax blissfully while priming your muscles for your next workout? Compression devices (in this case, intermittent pneumatic compression using air) have been tapped in medical settings for decades but are gaining more traction in the athletic world.

These devices slide on to encapsulate your entire leg—or hips or shoulders or full body if that’s your vibe—and cyclically deliver pulses of air to squeeze and knead your muscles with customizable levels of pressure, basically mimicking massage. “The main goal of any compression device is just to drive out swelling and start to un-gunk the hoses,” says Paul Longworth, athletic trainer and recovery specialist at PR Health. When we work out, we produce a lot of waste and byproducts, like lactate, that stick in the system and can contribute to skeletal muscle fatigue. It’s the lymphatic system’s job to pump all of that out. Compression takes our body’s natural response and speeds it up, helping “to force all of that out of the system,” says Longworth. In theory, this should help athletes get back out on the court or track faster with less pain and more mobility.

Many studies found benefits for cardiovascular recovery, heart rate variability, perceptual muscle soreness, swelling, and range of motion. One 2014 study evaluated the pain-to-pressure threshold (basically, how tender the muscles feel) in Olympic athletes and concluded that these devices are promising at accelerating and enhancing recovery following a rigorous training program. However, other studies suspect that these devices might be playing to the placebo. For example, a 2022 literature review found that compression had little effect on delayed-onset muscle soreness (DOMS) and a 2021 study found that they may provide short-term relief for DOMS but not continued relief from muscle damage.

Overall, it seems the research is promising enough for serious athletes to integrate it into their recovery regimen. Longworth uses these devices with his athletes, from MMA fighters to CrossFitters, after long training sessions when the athlete has to go into another training session or directly after a competition to assist recovery. However, where he sees the most promise is with endurance athletes, “who are building up a lot of swelling and metabolites over other athletes,” he explains.

If you are in the market for a pair of compression boots, there are a few considerations: First, you want to make sure that they’re sequential, “meaning they start squeezing from the distal end up to the proximal end,” says Longworth. “So if we’re talking about the legs, it squeezes at the foot or calf first and then slowly goes up the quad.” Basically, you don’t want one that has pressure all over the place at the same time because that won’t assist with lymphatic drainage. For example, the Normatec 3 uses overlapping zones that work up the leg to “replicate the natural muscle pumps and one-way valves of the legs,” according to the brand.

Another feature that some products incorporate is cold water for a cooling effect, but Longworth recommends steering clear of these devices. “If the goal is to move fluids through the system and we’re adding cold to that, that actually makes the liquids more viscous, and it closes off all of our capillaries,” he says. “Everything just tightens up, and it’s actually working against itself.”

One of the most profound benefits is that they’re easy to use—and hard to use incorrectly—making them a safe tool that is hard to overuse. The only time you should pause usage is after an injury, like a sprain, when you haven’t yet ruled out a fracture. “If you have a fracture and you add compression to that, you can actually cause more internal damage,” says Longworth.

At the end of the day, if you have expendable income and want a passive recovery tool that you can wear while you wind down in the evening, compression boots do offer a lot of benefits. While they come with a hefty price tag, they’re a hell of a lot cheaper than paying for a sports massage after every training session. But there are also much cheaper ways to drive out swelling, like active recovery. “You know what also drives out swelling?” Longworth says, “Muscles contracting. Movement.” A 2020 study found that while the Normatec is way more effective than passive recovery at clearing out blood lactate, it is not as effective as active recovery after 10 minutes of use. Longworth prefers movement for recovery over anything else: “If you just got on a spin bike and pedaled slowly for 20 minutes, you’re probably going to do yourself way more good than compression boots.”

Hannah Singleton is a freelance journalist who writes about fitness, health, wellness, and the environment. Her work has been featured in publications such as the New York Times, Wall Street Journal, GQ, Vox, Wired, National Geographic, Forbes, and Fast Company. She earned a master's degree in environmental studies from Prescott... Read more