When performed consistently, running is an effective way to boost your metabolism and give your lungs and heart a workout. Running is not without its drawbacks, however, as it can put a lot of pressure on your legs and feet. If you are overweight, have weak knees or wear shoes that don't fit your feet properly, running can cause damage to your knees, producing symptoms of bruising and swelling. Some diseases, such as arthritis, can also cause similar symptoms. If you experience bruising and swelling in your knees consistently after running, consult a doctor.
Bruising and swelling in your knees are indicative of trauma. Bruises are the result of blood vessels breaking and leaking blood into the tissue underneath your skin. The swelling can be the result of further trauma to the tissue, inflammation, or the pooling of blood. In severe cases, your knees may be stiff, and your range of motion may be limited. In most cases, you knees will be painful. If not, the swelling and bruising may be due to an underlying medical disorder.
A variety of underlying problems can lead to bruised and swollen knees after running. If you are wearing shoes that don't fit you properly, you may be adjusting your gait, which then puts strain on the bones, tendons or ligaments of the knee. Running on hard or uneven surfaces can lead to bruised and swollen knees, particularly if you are overweight or haven't exercised in a long time. A structural problem with your knees can lead to bruising and swelling due to pressure being put on the tissue and blood vessels. In some cases, an underlying medical disorder, such as arthritis, can be the cause.
Bruising and swelling in your knees should be treated with rest, ice, compression and elevation -- the RICE protocol. Apply ice to your knees every hour for 20 minutes at a time for up to four hours after running. Wrap the ice pack in a towel to avoid damaging your skin. Elevate your knees above your heart to help keep blood and other fluids from pooling and causing more swelling. Wrap your knees with a bandage to help with swelling and speed the healing process. Rest your knees as much as possible to allow them to heal more quickly and effectively.
If you are overweight or haven't exercised in over a year, try running on a softer surface, such as a rubber track, to ease the stress on your knees. Exercise for a shorter amount of time at less intensity until you have built up more endurance. Alternatively, use equipment that offers support to your knees, such as an elliptical machine, or perform other activities, such as cycling or swimming, that don't put as much pressure on your legs and knees. Once you have lost some weight and are more used to exercise, you can return to running. Consult a qualified professional regarding properly fitting shoes. Flat feet are a common issue, which usually requires shoes with arch supports. If taking preventative steps doesn't fix your symptoms, consult a doctor to rule out an underlying structural problem or medical disorder.