Marathon runners are long-distance runners (marathons are races that are 26.2 miles long). Studies have shown that the muscles of marathon runners contain an abundance of slow-twitch muscle cells. Which of the following statements about these fibers is true?

Question

Quizplus · Accepted Answer

Slow-twitch fibers are also known as Type I fibers and are mainly used for endurance activities such as long-distance running. They contain a high number of mitochondria, which are responsible for producing ATP aerobically through oxidative phosphorylation. This allows them to sustain activity for long periods without tiring quickly.

Marathon Runners Are Long-Distance Runners (Marathons Are Races That Are