Which property describes the extent of deformation of tissue under loading?

The correct answer is strain, which specifically refers to the measure of deformation that occurs in a material when it is subjected to stress. In the context of tissues in athletic training, strain quantifies how much a tissue stretches or compresses in response to an applied force relative to its original length.

Strain is often expressed as a ratio or percentage, which provides insight into how much a material can change shape under various loading conditions. This aspect is crucial for understanding how different tissues in the body respond to physical activity, injury, or rehabilitation processes.

Other terms, such as stress, load, and yield point, play different roles in the mechanics of tissue response. Stress relates to the internal resistance of the tissue to deformation when a load is applied, while load is the external force causing the deformation. The yield point signifies the moment at which a material begins to deform plastically, meaning it won't return to its original shape. Understanding strain helps in assessing the functionality and limitations of tissues during athletic activities.