Scuba diving places heavy demands on the human body. Divers must constantly overcome water resistance while carrying breathing equipment and other gear, and their underwater time is ultimately limited by both physical endurance and the amount of breathing gas they can carry.Scuba diving places heavy demands on the human body. Divers must constantly overcome water resistance while carrying breathing equipment and other gear, and their underwater time is ultimately limited by both physical endurance and the amount of breathing gas they can carry.[#item_full_content]