Can I practice suppression of breathing in adulthood?

In childhood, kids often compete with each other to see who can hold their breath the longest. Adults believe that this kind of nonsense or useless experimenting can only harm us. Therefore, they stop doing it. What a mistake! Isn't it now obvious that holding your breath is a strengthening exercise, when we see sports people doing it before difficult muscle training?

(This part is very important: not during but before!)

When you inhale you accept the energy from a negative state, with exhaling you pass it on to your body. When you suppress your breathing, you fix yourself in the centre, embrace the two energies and you are in a state of total balance. The suppressed air clears all the alveoli of the lungs and makes them work.

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