The challenge in sport freediving is that humans can destroy their own limits. By breathing in black and can hold back into deeper water and away. Wueng experiences when under the sea is quiet, without the good will the freediving. Concentrate for divers who can dive deeper than 100 meters, has petitioned chotra heart will just 20 times per minute. From the usual 60 times per minute. However, sports, freediving is considered a dangerous sport.