Mountain Trail Runner
When it comes to the athletic benefits of compression, perception may well be reality. (Photo: GibsonPictures/Getty)
Sweat Science

The Latest Science on Compression Gear

Over the past decade, research into compression sportswear has exploded. Here’s what the results reveal.

Mountain Trail Runner
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We’ve all got our biases, and mine is that I find compression garments uncomfortable. I don’t know why, but that’s just the way it is. Keep that in mind as you read what follows—because when it comes to the athletic benefits of compression, perception may well be reality.

Compression garments—initially long socks, but these days also half-tights, full leggings, arm sleeves, shirts, and even full-body suits—have been around for decades. The first sports-related study in this area, on lactate clearance while running or biking in medical-grade compression socks, was published back in 1987. And there’s been plenty of research since then: a comprehensive new review published in Sports Medicine by an Australian team led by Jonathon Weakley of Australian Catholic University synthesizes the results of 183 studies, most of them published in the last decade. But nailing down exactly what, if anything, these garments actually do remains surprisingly elusive.

There’s no shortage of theories. They might make you jump higher or run more efficiently. They might accelerate recovery, or reduce muscle damage and soreness. They might improve your balance and body awareness. They might make you feel good. And they might accomplish these things by reducing muscle vibration, enhancing blood circulation, or stimulating proprioceptive sensors.

So what does the evidence show? Summing up 183 studies isn’t easy, especially when the goals and methodologies are so inconsistent. Did the subjects wear compression during exercise, for an hour after exercise, or for the entire day? How tight was the compression at different places on the body? What was the garment made of? What did the subjects expect that it would do? That said, I’ll take a crack at summarizing the data: overall, the studies show that compression does very little, or perhaps nothing, but almost certainly doesn’t hurt you.

Here’s what that looks like in practice. There were 49 studies that measured lactate levels with and without compression; 40 of them found no effect. Another 39 looked at creatine kinase, a blood marker of muscle damage; 27 of them found no effect. For heart rate, 53 of 68 studies found no effect. In all these cases, the other studies found generally small positive effects. The picture is roughly the same for performance measures like jump height or time trial, and for measures of inflammation and swelling.

Things get a little more interesting when you look at subjective measures. For perceived muscle soreness in the days following a hard workout, 29 of 50 studies reported positive effects. For perceived muscle pain, six of nine studies were positive. That’s still not a fantastic batting average, but you start to see why these products are still on the market. Lots of people do like how they feel. (If you want to dig into the details of all the outcomes, the entire review is free to read.)

Of course, there are some important caveats. Compression is one of those things that’s very hard to blind. Many of the studies do try, for example by comparing compression tights to an ordinary pair of non-squeezing tights. But people aren’t stupid: they can tell when their legs are being squeezed and when they aren’t. So if they expect the tights to help them feel better, then it’s not surprising if they do.

Along those lines, the review notes a 2018 study in which volunteers ran two 5K time trials with an hour of rest in between. When the volunteers wore compression socks during the first 5K, they seemed to recover better and run the second 5K marginally faster than when they didn’t wear the socks at all. Interestingly, when these results were first presented at a conference back in 2015, they broke down the results based on which subjects thought the socks would help them. The believers actually ran their second 5K 3.6 seconds faster than their first one, while the skeptics got 17.9 seconds slower.

That’s not even the strangest result. In a 2015 study, researchers at Indiana University found that compression socks didn’t improve running economy (a measure of how efficiently you run). But compression believers did seem to have a more positive response than skeptics. That’s surprising because running economy, for the most part, isn’t under your conscious control: you can’t “try harder” to run more efficiently. One possibility is that some of the runners had prior experience with compression garments and had developed an intuitive feel for whether or not they benefited, but that seems like a stretch.

The upshot is that, among those 183 studies, you can find ample evidence for whatever position you want to defend about compression—that they’re a miracle, a scam, or somewhere in between. The authors of the review take a middle position. They’re clear that the majority of studies suggest no acute performance benefits, and not much support for reduced muscle damage and inflammation. But on the plus side, they conclude, there’s the improved perception of soreness—and “the research to date does not suggest that compression garments have a negative effect on performance.”

In other words, the glass is half full. Compression isn’t bad for you, so carry on if you like it. At this point, I can’t help checking the conflicts of interest: none are reported, and they say that “at no point was funding received by any of the authors for the writing of this manuscript.” I’m sure that’s true, but they’re interpreting that question very narrowly. It doesn’t take much digging to find this 2021 study, funded by the compression gear company 2XU, that features three of the authors from the review, or these two studies from 2020 that feature two of them, once again with a research grant from 2XU and direct support to one of the authors.

There’s nothing nefarious here: this is how the sausage gets made. But it would be naïve to think that financial influence doesn’t color your perceptions of ambiguous research—in the same way that my dislike of tight-fitting clothes makes me view the same findings skeptically. The overall body of research leaves open the possibility that compression does something useful, and it’s entirely to the credit of companies like 2XU that they’re funding high-quality research to find out what that might be.

As for practical takeaways, here’s where I end up. It’s clear that compression has physiological effects on the body: it’s not just a sugar pill or a PowerBalance bracelet. It’s not clear whether those effects have any practical utility. Lots of athletes, from casual to very elite, swear by their compression gear, and that’s not something to be dismissed. But I’d suggest being honest with yourself about your rationale: if you’re addicted to the squeeze, it’s because athletes you admire do it and/or you like the way it makes you feel, not because it’s backed by science.


For more Sweat Science, join me onTwitter andFacebook, sign up for the email newsletter, and check out my book Endure: Mind, Body, and the Curiously Elastic Limits of Human Performance.

Lead Photo: GibsonPictures/Getty

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