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Since the COVID-19 pandemic started, seeing others in masks has become commonplace. But have you seen a runner sporting a mask that makes them look a little bit like Darth Vader?
These face coverings, often called altitude or elevation masks, are training tools that claim to come with some benefits, like improving lung capacity and oxygen efficiency by restricting your airflow as you run. But do they really work?
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We talked to two experts to learn more about the method behind the masks: Shawn Arent, Ph.D., C.S.C.S., director of the Kinesiology and Applied Physiology graduate programs at Rutgers University and Director of the Rutgers Center for Health & Human Performance, and John Porcari, Ph.D., professor in the Department of Exercise and Sport Science at the University of Wisconsin-La Crosse and Program Director of the Clinical Exercise Physiology graduate program.
Do training masks simulate training at elevation?
While these devices are often called high altitude or high elevation training masks, those names are a bit of a misnomer.
“Training masks do not simulate elevation or altitude training,” says Arent.
When you go from sea level to elevation (or New York City to Boulder, CO, for example), there’s less atmospheric pressure—which causes the total content of oxygen, carbon dioxide, and nitrogen in the air to drop—and less partial pressure of oxygen, explains Porcari.
Training in those conditions—training at altitude—causes increased production of a hormone called erythropoietin (or EPO), which triggers your body to produce more red blood cells and form new blood vessels. That means your body can deliver more oxygen to your muscles, which means you can run faster and more efficiently, especially when you return to sea level.
Training masks, which typically feature one to three valves or vents, merely affect how hard it is for you to breathe—they do not affect the mix of gases in the air that you’re breathing, says Arent.
“Imagine you’re breathing through a vacuum hose, then a garden hose, then a straw, and then a cocktail straw. It’s going to get harder to breathe,” says Porcari. That’s essentially what a training mask does: reduce the amount of airflow into the lungs. So, unfortunately, you’re not going to get the same benefits that you would from training at elevation.
So, why would you ese one of these?
That’s not to say a training mask doesn’t have any benefits. Restricting the amount of air you breathe is called inspiratory muscle training; it’s often used by people with asthma, bronchitis, or emphysema. But it could benefit runners as well. “You’re basically increasing the strength of your respiratory muscles, which could mean you’re bringing more air into your lungs,” explains Porcari. “Then, you’ve potentially got more oxygen that can get into your bloodstream.” The more oxygen you can get to your muscles, the easier exercise will feel.
Porcari—in conjunction with the American Council of Exercise—tested the effect of training while wearing the Elevation Training Mask 2.0. He found that those who wore a mask showed a 15-percent increase in ventilatory threshold (a.k.a. the point at which your breathing starts to increase) and respiratory compensation threshold (a.k.a. the point at which lactate accumulates at faster rates than the body can remove it—or the highest sustainable level of exercise intensity).
Those things could have a bigger influence on performance. Let’s say a runner can run eight miles per hour before they hit their respiratory compensation threshold; if they can improve that threshold by 15 percent, they’ll be able to run 9.2 miles per hour—that’s a huge difference. But more research has to be done to replicate Porcari’s findings.
From an anecdotal standpoint, training masks might help you breathe better on the run, says Arent. “People I know who’ve used these devices have said it makes them breathe less with their chest and more with their diaphragm, which would be a good thing,” he says. If you’re breathing with your chest, you’re only using a small portion of your lungs, which forces you to take more breaths to get enough oxygen; when you breathe deeper into your diaphragm, you can take fewer breaths while getting more oxygen into the deeper parts of your lungs. It’s more efficient, and it will help control your heart rate—which puts less stress on your body so you can run faster and longer without fatigue.
Should you buy a high altitude mask?
It’s not necessary. “There’s not a huge upside to wearing a training mask, especially if you’re fairly highly trained,” says Arent. Despite the ventilatory and respiratory compensation threshold benefits, you likely won’t see massive performance changes. And, for most people, the pulmonary system is rarely the limiting factor in endurance exercise, Arent adds—it’s more likely to be your musculoskeletal or cardiovascular system.
Of course, using a training mask will elevate the relative intensity of a workout because it will make breathing more difficult, says Arent. “There are times in training when suffering isn’t such a bad thing,” he says. “It’s a non-optimal condition that forces adaptation.”
But it’s not an everyday training device; rather, it’s something you might want to incorporate every once in a while if you’re looking for an added challenge, says Arent.
If you're intrigued, there’s no real harm in trying one (so long as you don’t have any pre-existing conditions and you get approval from your doctor or health professional) except of course, the price tag: They retail between around $20 and $100.
To test it, “you may want to start wearing it on shorter runs, then add it into longer runs and go from there,” says Porcari. “You should build up to higher intensities.”
Just don’t expect it to be a magic bullet. A good interval or tempo workout can be just as challenging as an easy run with a mask on—and potentially more beneficial.
Training Masks
TRAININGMASK Training Mask 3.0
The latest iteration of the OG training mask lets you easily adjust the air flow via a dial on the single vent.
Friorange Friorange Sport Workout Training Mask
For those on a budget, this altitude training mask will work in a pinch.
The ergonomic, slip-resistant design makes this mask a comfortable fit on even the longest runs.
FDBRO FDBRO Workout Mask
This choice is comfortable and skin-tight, promising no looseness or extra noise.
