The surprising effects of mask wearing on fitness
You might think that there are some hidden physical benefits to exercising in a mask.
Anything that uncomfortable must be good for you right!?
We’ve all experienced the anxiety-inducing claustrophobia that comes from not quite being able to fill your lungs with the oxygen you need. Surely smothering your mouth and nose with a constricting piece of material has to give us some sort of training benefit?
You’d think so wouldn’t you?
And before we started researching this article, we did too.
We expected to find that wearing a mask would increase energy expenditure, improve recovery times, train breathing thresholds, improve long term power outputs, increase the release of growth hormone, strengthen respiratory muscles, lower resting respiratory rate, lower heart rate, and a whole bunch of other stuff that would make mask wearing a training advantage.
So, initially, we set out to write this article to encourage people to keep exercising, even when wearing a mask. We wanted people to find the positive in a negative situation and turn this oppressive inconvenience to their advantage. We wanted to inspire people with the secret physical benefits of training in a mask.
But then we started looking… and physical benefits aren’t what we found.
Sure, there is a performance benefit to wearing a mask during exercise, but it probably isn’t what you think.
If you exercise in a mask, you will improve your fitness (VO2 max and power output). But you won’t improve it by more than if you were exercising without a mask. There seems to be no real added physical benefit to wearing a mask. Wearing a mask doesn’t make a difference to training benefit – negative or positive.
In their 2020 paper, “Return to training in the COVID-19 era: The physiological effects of face masks during exercise”, Epstein et. al. found that “…in healthy subjects, short-term moderate-strenuous aerobic physical activity with a mask is feasible, safe, and associated with only minor changes in physiological parameters…”
Training in a mask however, did delay the return of oxygen saturation to normal levels, according to research from Zoll et. al. in 2006. This creates a hypoxic environment which could create a long term improvement in your ability to resist fatigue, as well as an increased efficiency in your body’s ability to use oxygen and fuel. But nothing is free, and the hypoxic benefits may be cancelled out by this delayed return to normal oxygen saturation between training sessions.
So what can we take from this?
At least some of the difficulty people experience from exercising in a mask is in our heads. Sure, at very high intensities, it can be hard to suck air in, but maybe the physical difficulties are less physical and more mental.
Shaw et. al. in 2020 found that “Wearing a face mask during vigorous exercise had no discernible detrimental effect on… exercise performance in young, healthy participants.”
So if there’s no detrimental effect on exercise performance, why have so many of us experienced increased difficulty exercising with a mask?
The reason was summarised well in the 2020 study “Face Masks and the Cardiorespiratory Response to Physical Activity in Health and Disease”. “There might be a perceived greater effort with activity, but the effects of wearing a mask on the work of breathing, on gases like oxygen and CO2 in blood or other physiological parameters are small, often too small to be detected…”
One of the authors of the study went on to say:
“Wearing a face mask can be uncomfortable. There can be tiny increases in breathing resistance. You may re-inhale warmer, slightly enriched CO2 air. And if you’re exercising, the mask can cause your face to become hot and sweaty. But these are sensory perceptions. They do not impact cardiopulmonary function in healthy people. So while (shortness of breath) might be increased with a mask, you have to weigh that against the reduced risk of contracting COVID-19, knowing that the physiology is essentially unchanged.”
Another 2020 paper agrees. In the paper “Effects of wearing a cloth face mask on performance, physiological and perceptual responses during a graded treadmill running exercise test”, the authors commented that reduced levels of performance when wearing a mask were “…attributed to perceived discomfort associated with mask-wearing” rather than actual physical changes.
This opinion was echoed by the author of another 2020 study. “The more noticeable impact is the psychology of trying to exercise while wearing a mask. If you feel uncomfortable in a mask, you may reflexively contract your muscles, changing the way your body reacts to exercise.”
In short we perceive the exercise to be harder in a mask… but it may be more in our heads than our bodies.
So what’s the benefit of exercising in a mask?
It’s not physical, but psychological.
In most parts of our life, we do everything we can to make things easy. We have a team of labour saving devices and machines designed to make our life as passive as possible.
But exercise is an exception. Exercise is one of the few parts of our life that we intentionally want to make more difficult. By choosing to apply this positive stress to our body, our body adapts and improves.
If we lift heavy things, we’re limited by our strength, and as a result, our strength improves. If we do exercise that causes us to breath hard, we’re limited by our heart and lungs, and as a result, our cardiorespiratory endurance improves.
But this phenomenon doesn’t end with the physical elements of exercise.
If we challenge ourselves psychologically with uncomfortable situations, we’re limited by our mental game, and as a result, our mental toughness improves.
Training in a mask should be seen as an opportunity to challenge the mind – something we spend so much of the rest of our lives trying to avoid. Far from moving away from hardship, we should move towards it.
We should view masks as an opportunity. An opportunity to become tougher, grittier and more resilient.
So while the benefit of mask training may be more psychological than physical, if our mental game is stronger, our physical game will be stronger too. The toughness and resilience we’ll build will serve us well in training, and in life.
If you’re someone who exercises less because of the need to wear a mask, just remember that exercise is one of the most powerful things you can do for your long term health. Using a mask as an excuse to break your exercise habit could have dire long-term consequences.
If you feel the need to reduce your exercise intensity when wearing a mask, that’s absolutely fine. You could even consider increasing the length of your exercise session to counteract the reduced intensity. And if you’re doing interval training, increase the length of your recovery periods to allow levels of oxygen saturation to return to normal levels.
There are loads of benefits of lower intensity exercise, but possibly the most important benefit is the long-term maintenance of your exercise habit.
Of course, the research in this area is coming fast, so stay up to date with the latest information as new knowledge emerges.
- Driver S, Reynolds M, Brown K, et al. Effects of wearing a cloth face mask on performance, physiological and perceptual responses during a graded treadmill running exercise testBritish Journal of Sports Medicine Published Online First: 13 April 2021. doi: 10.1136/bjsports-2020-103758
- Hopkins, S., Dominelli, P., Davis, C., Guenette, J., Luks, A., & Molgat-Seon, Y. et al. (2021). Face Masks and the Cardiorespiratory Response to Physical Activity in Health and Disease. Annals Of The American Thoracic Society, 18(3), 399-407. doi: 10.1513/annalsats.202008-990cme
- H. Inness MW, Billaut F, Walker EJ, Petersen AC, Sweeting AJ, Aughey RJ. Heavy resistance training in hypoxia enhances 1RM squat performance. Frontiers in Physiology. 2016; 7.
- Puype J, Van Proeyen K, Raymackers J, Deldicque L & Hespel P. Sprint Interval Training in Hypoxia Stimulates Glycolytic Enzyme Activity. Medicine & Science in Sports & Exercise. 2013; 45: 2166- 2174.
- Shaw K, Butcher S, Ko J, Zello GA, Chilibeck PD. Wearing of Cloth or Disposable Surgical Face Masks has no Effect on Vigorous Exercise Performance in Healthy Individuals. International Journal of Environmental Research and Public Health. 2020; 17(21):8110. https://doi.org/10.3390/ijerph17218110
- Zoll J, Ponsot E, Dufour S, et al. Exercise training in normobaric hypoxia in endurance runners. III. Muscular adjustments of selected gene transcripts. Journal of Applied Physiology. 2006;2005;100:1258-1266.
Dan Williams is the Director of Range of Motion and leads a team of Exercise Physiologists, Sports Scientists, Physiotherapists and Coaches. He has a Bachelor of Science (Exercise and Health Science) and a Postgraduate Bachelor of Exercise Rehabilitation Science from The University of Western Australia, with minors in Biomechanics and Sport Psychology.