The average bruise lasts 10 to 14 days, reports KidsHealth.org, a division of the Nemours Foundation. If you've ever bumped your shin on a table or taken a hard hit when playing a sport, then you've likely seen the mark on your leg slowly turn from bright red to black-and-blue over the course of a few hours. The bruise is likely also tender to the touch. You can heal bruising quickly by applying a simple formula to bring down the swelling and soothe the pain.
Evaluate the bruise immediately after it happens, recommends the Mayo Clinic. Check for signs of broken skin around the bruise, which would require sterilization and immediate bandaging. If it is a true contusion and you can only see redness on the skin, proceed to treat it as a bruise.
Stop doing whatever you were doing when you received the blow. If you were playing a sport, it's best for the healing process if you stop and rest. Continuing to play can make the bruise look worse and might even cause further injury. Avoid overworking the muscles in the injured area.
Apply a cold compress of ice to the bruise as soon as possible, suggests the U.S. National Library of Medicine. Wrap a few ice cubes in a washcloth and apply it to the skin for 15 minutes out of every hour. Never apply ice directly to the skin. Evaluate the bruise each time you remove the ice to see if the swelling is going down.
Bandage the bruise to give it the benefit of compression. Use a lightly tied cloth bandage, recommends the American Academy of Orthopedic Surgeons. This can help relieve some of the swelling and pain related to the bruise and allow it to heal faster. You can also use the bandage to hold the cold compress in place for a longer period of time. Just be sure to wrap it lightly enough that you don't feel pain or loss of circulation.
Elevate the bruised body part to a position above your head. You may need to recline or arrange pillows so you can be comfortable, but it will help to reduce the swelling for faster healing. When the bruise is below the heart, blood can pool in the bruise, causing it to look even worse.