Is breathing through your nose the secret to reaching peak fitness?
By Sarah Berry
World No.1 women’s tennis player Iga Swiatek was as confused as the rest of us about why she was practising with tape covering her mouth last week.
During a press conference, after photographs of her training in Montreal were published around the world, the 22-year-old from Poland said: “I don’t get it either... but, it’s harder to breathe when you’re only breathing with your nose, and it’s easier for my heart rate to go up, you know? And I think it has something to do with endurance.”
Iga Swiatek trains wearing tape over her mouth.Credit: Zuma Press
There are several possible reasons for using mouth tape, says Chris Abbiss, a professor of exercise physiology at Edith Cowan University.
Swiatek’s coaches may have been attempting to induce hypoxia, he says, by depriving oxygen supply during training to improve “oxygen debt”, which is the capacity to exercise anaerobically (at high intensity without oxygen) and even lung volume.
According to the Australian Institute of Sport, hypoxic training is used to improve performance in sport disciplines requiring high levels of aerobic endurance.
It’s an approach athletes have been using for decades, says Tony Blazevich, a professor of biomechanics at Edith Cowan University.
“The idea of training in hypoxia is that they tax their aerobic system without having the muscles work too hard,” says Blazevich.
“Many athletes use their muscles a lot and need to let them recover, so they might try this training to continue the aerobic adaptations whilst minimising stress on muscles.”
How effective mouth taping is at inducing hypoxia, however is unclear.
“I am not aware of any published research on this in exercise,” says Abbiss.
He suspects Swiatek’s tape was less likely an attempt to induce hypoxia and instead perhaps a technique aimed at improving respiratory muscle strength.
Improving the function of the respiratory muscles through specific exercises can make breathing more efficient and alter our perception of effort and exertion. Still, any technique an athlete uses for hypoxia or respiratory muscle strength should be done under close supervision.
“It could be very problematic in the event of a cardiovascular or other similar episode,” Abbiss says. “This is not something I would suggest amateur athletes conduct.”
Rory WarnockCredit: Instagram
Alternatively, the purpose of the mouth taping exercise may simply be psychological. “It’s a ‘different’ and interesting way to ask an athlete to practice whilst under duress,” says Blazevich. “This doesn’t only help them to do physical work whilst under stress, without truly placing them under stress (we can open our mouths or breathe properly whenever we want), but to practice making correct sporting decisions under duress.”
For ultramarathon runner and breath work coach Rory Warnock the point of mouth tape is to force yourself to breathe through the nose, which he believes has improved his own athletic performance and endurance.
For the past three years, the Bondi resident has taped his mouth during runs to prove this point. “You can adapt, and you become efficient and effective at breathing through the nose,” he says.
The intention of breathing through his nose (and occasionally taping his mouth) is to increase oxygen delivery.
“Nasal breathing will help slow the rhythm down,” he says, adding that by doing this people can increase the oxygen that makes its way into working tissue. “It’s about slowing the breath down to increase the oxygen into the tissues.”
Warnock also points to a study, which suggested people are up to 42 per cent more hydrated when they breathe through their nose, as they lose less water when exhaling.
When he started nasal breathing while running, he felt as though he might suffocate.
“It felt hard at first, but over time, the body adapts to that stress,” he says, noting that his pace eventually improved from five minutes and 30 seconds a kilometre to about four minutes and 30 seconds a kilometre, and a heart rate of 156 beats per minute in the last half-marathon he ran with mouth tape on.
Abbiss says that various studies have compared mouth and nasal breathing but exclusively restricting to one (or the other) is unlikely to benefit athletic performance.
“Some studies have shown little direct influence while others have shown negative effects of restricting to nasal breathing,” he says pointing out that the improvements are likely to come when doing lower-intensity exercise, not when we are pushing as hard as we can.
Warnock, who works with athletes including the Sydney Swans, says that since training this way he has had personal bests in everything from a five-kilometre run to a 250-kilometre ultra. He acknowledges that while sprinting, he switches to mouth breathing, but credits nasal breathing for the improvements across the board.
“When you train in that way, in that environment, it helps you build that aerobic base, and the better you can build the aerobic base, the better your anaerobic will be as well,” he says. “I put so much of competing in these races down to the way that I breathe.”
While Warnock encourages everyone to practise nasal breathing – saying the nose is designed to breathe and smell, while mouths are for eating and speaking – it doesn’t mean we should go all Swiatek about it.
Abbiss, meanwhile, is clear that he would not recommend anyone tape our mouths during their next exercise session. “In fact, this similar outcome could be achieved without taping and instead encouraging nose breathing.”
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