There are muscles that support your breathing. Just like any other muscle in your body, the best way to make them stronger and more efficient is to strength train them. Imagine a person who trains or exercises with weights, machines or exercise bands. When a person is training, he or she must “work” against something, a resistance.
In this case, lifting and lowering the weight. The weight creates a workload – resistance – for the muscles to work against and overcome. The more the person repeats the pattern of the exercise, the stronger his or her muscles become. As it becomes easier to do the exercise the person can increase the threshold to help make the muscles stronger.
That is threshold resistance, a proven method of training used only by PowerLung. When you breathe in and out through PowerLung, you are working against a threshold of resistance that is the same for every breath. You are not breathing through a restricted orifice where the load can be reduced just by changing the way you breathe.