A Muscle That Assists Another by Preventing Movement at Another

Question

A muscle that assists another by preventing movement at another joint is called a(n)
A) synergist.
B) fixator.
C) agonist.
D) prime mover.
E) antagonist.

Accepted Answer

A fixator muscle is one that stabilizes the origin of the prime mover muscle so that it can function more efficiently. This means that it prevents movement at a joint other than the one being acted upon by the prime mover. Thus, a fixator muscle assists another muscle by preventing unwanted movement, rather than by contributing to movement, as is the case with agonists or prime movers. Synergist muscles help prime movers, while antagonists oppose their action.