Question

5. A person participates in a daily stretching program of the hamstring muscles and, over time, increases the permanent flexibility and length of the hamstrings. Which of the following areas on the Stress-Strain curve represents this new condition of the hamstring muscles?

A. Elastic region
B. Toe region
C. Plastic region
D. Mechanical failure

Answer 1

The permanent increase in hamstring muscle flexibility and length due to a stretching program is represented by the plastic region on the Stress-Strain curve.

Step-by-step explanation:

When a person participates in a daily stretching program and increases the permanent flexibility and length of hamstring muscles, they are affecting the plastic region of the Stress-Strain curve. The plastic region represents the range in which permanent deformation occurs. In this case, the tissue adapts to the stress over time, leading to an increased length and flexibility of the hamstring muscles. This alteration does not revert to the original state once the stretching force is removed, indicating that the change is not merely elastic but plastic in nature.