Strict mortality or rigor mortis is stiffening the body after death.
After death, the body begins to get cold and from about two to six hours after death, the muscles begin to stiffen, probably because the actin and myosin filaments of the muscle slide together. The rigor mortis begins at the eyelids, jaw and neck and extends beyond all body parts within six hours. Contrary to what some people think, rigor mortis will occur faster at high ambient temperatures than in case of cold. This is because the underlying chemical reaction occurs at higher temperatures faster. Depending on the ambient temperature, the rigor mortis lasts one to three and a half days. When taking or 'taking care', the body of the deceased is sometimes massaged. This reduces stiffness.
Virtually immediately after death, the body changes color. Because the heart does not pump blood around, the blood drains away from the skin. This makes the skin pale and bleak. Also, the blood drops to the lowest part of the body, in the back of the buttocks and the back. In the places where the blood collects, purple veins (livor mortis) develop. Medications can accelerate discoloration.
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