Tissue trauma, local bruising, different parts of the body, different range of bruising fading time also varies. Generally, bruises in smaller areas with better blood flow can fade in a week or so, such as bruises on the head and face, but bruises in larger areas on the limbs and trunk can take about two weeks to fade. The bruise is caused by subcutaneous bleeding, the action of external force makes the subcutaneous capillaries rupture and bleed, the bruise exists under the skin, and a bruise is seen on the unbroken skin. If there is no skin breakage at the time of injury, local cold compresses can be applied to reduce bleeding, swelling and pain by local capillary constriction. 24 hours after the injury, hot compresses can be applied to improve local blood circulation, which is conducive to the absorption of the bruise and exudate at the injury site and accelerate the fading of the bruise.