What is rigor mortis?

Rigor mortis refers specifically to the stiffening of the muscles that occurs after death. This physiological process begins several hours post-mortem and is a result of chemical changes in the muscles when the body stops producing energy. The muscles initially relax, and then they become stiff due to the accumulation of lactic acid and other biochemical substances as the cells use up their oxygen and energy stores. This condition is a significant factor in forensic science, as examining the onset and duration of rigor mortis can help investigators estimate the time of death, which is crucial for criminal investigations. Understanding rigor mortis aids in determining the circumstances surrounding a death and advancing the overall investigation process.