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.
To put it in perspective for a friend, see how high you can count during that time. Believe it or not, there actually have been people who have held their breath for even longer than 11 minutes, though. The Guinness Book of World Records has a special category for holding your breath underwater. Unlike the freedivers who practice static apnea, the Guinness guidelines allow contestants to breathe pure oxygen for up to 30 minutes prior to their attempt.