Under water for minutes, without equipment – just with your own oxygen in your lungs. Apnea divers provide top mental performance for this. Our author learned from one of the best how amateurs can do it too.
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Under water for minutes, without equipment – just with your own oxygen in your lungs. Apnea divers provide top mental performance for this. Our author learned from one of the best how amateurs can do it too.
source site