The Skeletal Muscle System. Skeletal muscles are the muscles found in your legs and arms and throughout the body. The skeletal system is different from the smooth muscle system in organs like your liver and the cardiac muscle in your heart because the skeletal muscles contract voluntarily.he skeletal system is different from the smooth muscle system in organs like your liver and the cardiac muscle in your heart because the skeletal muscles contract voluntarily.
With the benefit of breathing pure oxygen first, the current Guinness World Record for holding your breath underwater is held by Ricardo Bahia of Brazil at a whopping 20 minutes 21 seconds! Most people in good health can hold their breath for approximately two minutes.
The deeper a marine mammal has to dive for food, the longer it is going to need to be able to hold its breath to be successful. Humans who have trained can hold their breath underwater for around 20 minutes, but the average person can only hold his or her breath for 1 minute.