Can Altitude Masks Really Replicate Altitude Training?

Wouldn’t it be great to get the benefits of living and training at altitude without having to uproot your entire life?

One way to do that is with an altitude tent, which uses compressed nitrogen gas to thin the oxygen in the air to replicate high-altitude living in a tent-like shroud around your bed.

Aside from the obvious drawbacks of a claustrophobia-inducing plastic canopy, altitude tents are also extremely costly—upwards of $10,000 for some models.

So, unless you’re a pro runner with a big contract from a shoe company, tents are out of the question too.

Damn.

But recently, companies marketing “altitude masks” for very reasonable costs have made claims that these relatively simple masks can provide the same benefits of training at altitude.

These masks don’t actually generate lower oxygen concentrations in the air that you inhale, like an altitude tent; they use mechanical valves to generate resistance to inhalation instead.

Can this respiratory muscle training produce the same benefits of living or working out at altitude?

Today we are going to find out. By looking at the research on these altitude training masks to replicate high elevation, we will see if it is really worth purchasing one of these if you have a upcoming race at altitude (or just want an edge) or if you are better off just putting the extra time and money into something else to help your training.

Altitude Masks DO NOT Work

There’s been a flurry of scientific studies looking into the potential benefits of altitude masks.

But wait:

There are a few drawbacks to all of this research.

The quality of the studies varies considerably, and some studies are authored by people with vested interests in the results (like owners of a company that makes an altitude mask!).

So we have to be a little more critical when reviewing the science.

A 2002 study by researchers at Texas Tech University investigated the effects of “respiratory resistance training” (the mechanic behind altitude masks) in seven collegiate distance runners.

The athletes undertook a slew of performance tests before and after a four-week respiratory muscle training program to identify whether the program had any effect on their fitness.

After the four weeks, the runners showed marked gains in direct tests of their respiratory muscle strength and endurance—basically, how “hard” they could breathe—but showed no change in their maximum oxygen consumption during exercise (as measured by VO2 max) or in their performance over a run to fatigue at 85% of VO2 max pace.

One drawback of this first study is its lack of a control group.

A better-designed study would have another group of subjects which did not undergo respiratory muscle training to serve as a comparison.

Fortunately, a study with just this design was carried out by D.W. Morgan and coworkers at Arizona State University.

In their study, nine moderately-trained cyclists were divided into two groups, one which underwent a three-week respiratory muscle training program, and a control group which continued their regular training.

As with the first study, the cyclists had their breathing muscle strength and endurance measured before and after the training, as well as their VO2 max and their performance over a cycling ride to fatigue.

And again, the results were the same: the respiratory muscle training significantly improved performance on breathing-related tests like maximum ventilatory power, but led to no improvement compared to the control group in the cyclists’ VO2 max or their performance in the endurance ride.

Several other studies, many of them well-designed, have also found no significant benefit to respiratory muscle training.

Or DO Altitude Masks Work?

In contrast, many studies have found beneficial effects of respiratory muscle training.

One example is a 2004 study by researchers at the University of Arizona which also looked at cyclists, parsing 20 trained subjects into a respiratory muscle resistance training group, a “sham” group, which did simulate breath training against no resistance, and a true control group which did no breath training.

This study did find an increase in VO2 max in the experimental group compared to both the sham and controls.

A number of other studies have supported respiratory muscle training in rowing, swimming, cycling, and intermittent shuttle-run tests.

Research can be biased

Resolving the controversy is problematic because there are many different studies with vastly different protocols:

Some studies use respiratory training for three weeks; others, 15 weeks.

As you can imagine, this has a huge impact on results!

It gets worse:

The studies involve evaluations of wide range of sports.

The shuttle run is not the same as competitive rowing or swimming or long-distance cycling!

Also:

The participants of the studies were at various experience levels. The participants which ranges from totally sedentary to NCAA Division I distance runners.

Given all this, it’s no surprise that the results vary so much.

Any conclusive studies?

Some researchers have attempted to pool the results from several studies to discern whether any net benefit can be detected

One such “meta-analysis study” published in 2012 concluded that there appear to be some benefits to respiratory resistance training, but these are more strongly exhibited in unfit subjects, and less so in trained athletes.

This effect is fairly common—when you’re an out-of-shape couch potato, pretty much any kind of training will get you in better shape. In contrast, a high-level athlete requires a very sport-specific stimulus to elicit further improvement.

There is also evidence that the scientific literature on respiratory muscle training is skewed by an effect called publication bias, where studies with a negative result (i.e. no benefit to respiratory muscle training) are not published.

This is either because scientific journals deem them not noteworthy enough or because the authors themselves decided not to publish.

This could artificially inflate the apparent usefulness of respiratory resistance training, as measured by review article and meta-analyses.

Does Breathing Harder Help You Run Faster?

One common misunderstanding about the studies on altitude masks is the potential benefit of improving the “strength” of your breathing.

Sadly, improving your respitory muscles (how hard you can breathe) will not lead to an increase in performance.

This seems backwards, since we certainly breath hard when running fast.

However, in running, the main problem isn’t usually getting air into your lungs anyways—it’s getting oxygen from the air into your blood, and then putting that oxygen towards a useful purpose in your leg muscles

Improving your lung strength and being able to exhale and inhale more forcefully will not help with this.

Are altitude masks worth it?

At this point, there isn’t enough evidence to support using an altitude mask or other breathing muscle training device as part of your training regimen.

The wide range of study quality and design are just too shaky to put faith in.

Given that there are so many better things to spend time and money on to improve your performance, like lighter shoes, interval workouts, a strength training routine, or better nutrition.

Getting an altitude mask is not a worthwhile investment unless better research comes out supporting its use in well-trained distance runners.

What will help you though when it comes to breathing, is listening to this podcast interview with Patrick McKeown on how to get the same benefits as altitude running by changing the way you breathe!