Which stretching procedure follows an initial passive stretch and involves a short-duration isometric contraction of the stretched muscle, then a contraction of the antagonist to move to a new barrier, followed by a hold?

• A. Post Isometric Relaxation (PIR)
• B. Contract Relax Antagonist Contract (CRAC)
• C. Active Isolated Stretching
• D. Muscle Energy Technique (MET)

Answer: (B)

This sequence uses two neuromuscular mechanisms to gain more range: autogenic inhibition from the isometric hold of the stretched muscle, followed by reciprocal inhibition from contracting the antagonist to move past the initial barrier.

First, you place the muscle in a passive stretch to its end position. Then you hold and perform a short-duration isometric contraction of the stretched muscle. This brief contraction triggers autogenic inhibition via the Golgi tendon organ, which reduces the muscle’s resistance and allows it to relax more after the contraction. Next, the antagonist muscle contracts, which produces reciprocal inhibition of the stretched muscle and lets the joint move further into a new barrier. After reaching that new range, a hold helps stabilize the increased length.

This exact sequence—passive stretch, short isometric contraction of the stretched muscle, antagonist contraction to reach a new barrier, then hold—is characteristic of the contract-relax antagonist-contract approach.