Jeff is holding his arm out to support a heavy book. After a while of maintaining the contraction, he is no longer able to exert any muscle force. This is a result of which phenomenon?
A) glycogenolysis
B) muscle fatigue
C) summation
D) aerobic respiration

Question

Quizplus · Accepted Answer

Muscle fatigue is the point at which the muscle can no longer generate any force. This happens when the muscle fibers are exhausted and unable to maintain the contraction any longer. Glycogenolysis is the breakdown of glycogen into glucose, which is used for energy during muscle contraction. Summation is the increasing tension produced by a muscle fiber when a second stimulus is applied before the muscle fiber has relaxed from the previous stimulus. Aerobic respiration is a process by which the body produces energy through the consumption of oxygen.

Jeff Is Holding His Arm Out to Support a Heavy