Which of the following correctly characterises a "fast-oxidative " type of skeletal muscle fibre?

Options

A. Few mitochondria and high glycogen content
B. Low myosin AT Pase rate and few surrounding capillaries
C. Low glycolytic enzyme activity and intermediate contraction velocity
D. High myoglobin content and intermediate glycolytic enzyme activity

Answer

D

Explanation

Fast-oxidative-glycolytic fibres are an intermediate type that are designed to contract rapidly but to resist fatigue. They utilise both aerobic and anaerobic energy systems, thus, they are red fibres with high myoglobin (which faciliates production of ATP by oxidative phosphorylation), but they also have a moderate ability to generate ATP through glycolytic pathways.