For antagonistic muscle groups to move a limb, flexor contraction occurs coincident with
A) contraction of the extensor.
B) relaxation of the extensor.
C) no changes in the extensor.
D) contraction of the tendon.

Question

Quizplus · Accepted Answer

To move a limb, the flexor and extensor muscles work in opposing pairs. When the flexor contracts, the extensor must relax to allow movement. Therefore, flexor contraction occurs coincident with relaxation of the extensor.

For Antagonistic Muscle Groups to Move a Limb, Flexor Contraction