“At rest, we have a certain volume our lungs can use,” says Probert. “During exercise, it becomes more challenging to breathe due to the increased effort, but also the increased demands of the body, meaning it needs more oxygen. There are two ways to get more oxygen in—breathe more quickly or breathe more deeply. During exercise, you’ll see a combination, with both going up as intensity increases.
“You have an excellent lung capacity but didn’t utilize it fully at all intensities, which we see often. Your breathing was a little erratic throughout the whole test, with an inconsistent breathing frequency and depth. Your peak lung volume usage was three minutes into the test, using 4 liters per breath at 140bpm. By VO2 max, you were only moving 3.3 liters per breath and instead had compensated by breathing much more quickly.
“Breathing more consistently, with a steady increase in breathing rate, allows you to match your strides to your breathing rate and can contribute to perceived effort levels. The ‘best’ way to breathe for running is still undetermined but research suggests breathing too quickly will increase perceived effort levels—and if you feel like you’re working harder, you’re less likely to push as hard for those performance improvements.”