What does rigor mortis refer to?

Rigor mortis specifically refers to the phenomenon of muscle stiffening that occurs after death. It is a biochemical process that results from the depletion of ATP (adenosine triphosphate) in the muscle fibers, leading to the contraction of the muscles and their subsequent hardening. This stiffening generally begins within a few hours after death, usually starting in smaller muscles before affecting larger ones, and is a key indicator that can be used to determine the time of death during forensic investigations.

Understanding rigor mortis is crucial for healthcare professionals, as it highlights important physiological changes that occur after death, which can inform various aspects of care, handling of the deceased, and legal considerations. In contrast, the other options describe processes or states that do not accurately capture the meaning of rigor mortis.