This new study (2019) looks into whether chronic IMT improves hypoxic endurance exercise performance.
Endurance exercise performance
The study, in the International Journal of Sports Physiology and Performance, is using a cycling time trial to measure endurance exercise performance. Endurance exercise is typically performed at submaximal intensity. The purpose of this is to estimate VO2max, or ‘aerobic fitness’. The measurement VO2max is the maximum amount of oxygen a person will consume during intense exercise. In fact, cycling time trials offer the ideal exercise to increase both heart rate and breathing. Similarly, so do running and swimming.
What is IMT?
IMT is a form of resistance training for the breathing muscles. The term IMT stands for inspiratory muscle training. The inspiratory muscles, the breathing muscles, are the ones that draw air into the lungs. The main inspiratory muscle is the diaphragm. Like any other group of muscles, the inspiratory muscles benefit from training too. Inspiratory muscle training, such as with POWERbreathe, provides the stimulus for that training. Following IMT, the breathing muscles adapt and become stronger after only a few weeks. This results in exercise feeling easier and an improvement therefore in performance.
Although breathing comes naturally, some of the time it can feel like an effort. This may be due to the demand endurance exercise places on breathing. It may be due to a respiratory issue. Either way, it’s not uncommon for the respiratory muscles to fatigue, just like any other muscle.
If the respiratory muscles are weak from disease or exercise is overloading them, breathing demand will not be met. As a result, breathing will start to feel shallow and rapid. Sustaining this type of breathing is impossible. Furthermore, the more rapid the breathing, the more oxygen they require and the more carbon dioxide they produce. Consequently, oxygen is re-directed from the skeletal muscles, such as arms or legs, to the breathing muscles, where it is most needed. This results in fatigue of the skeletal muscles.
Inspiratory muscle training helps the body meet the needs of both the respiratory muscles and the skeletal muscles by improving their strength and stamina. The way IMT achieves this is by providing a resistance to breathe in against. POWERbreathe IMT is just like a ‘dumbbell for your diaphragm’.
Data from this recent study suggest that,
“performing 6 weeks of inspiratory muscle training may benefit hypoxic endurance exercise performance lasting 30-40 minutes.”