You are a physical education teacher at a middle school that

You are a physical education teacher at a middle school that feeds into district high school. Coaches at the HS have asked all physical educators to try and identify students who demonstrate potential athletic ability. Students\' bodies can change dramatically from middle to high school. But one thing is constant--percentage of fast and slow muscle tissue. How important is the predominance of fast or slow twitch for high school athletics? Is that something that you might use? If so, how?

Solution

The maximum contraction achieved by the muscles indicates muscular strength. The ability of the muscles to contract against resistance is known as “muscular endurance.” Endurance training does not increase the fiber length. But it increases the number of myoglobins in muscle fibers and improve the ability to obtain ATP from oxidative phosphorylation.

Endurance training decreases the number of fast glycolytic muscles (type IIX) fibers and increases the number of fast oxidative (or type IIA) fibers.

Resistant training i.e. high intensity exercises in frequent periods results in increased muscle fiber length (hypertrophy). The fast oxidative muscles or the type-II muscle fibers become thicker.