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. It could even lead to a knee bruise after running.
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 typically indicate inflammation in your knees. Less commonly, an underlying medical condition is to blame.
Knee Bruise After Running
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.
The location of your swelling or bruising can help determine the structures that are potentially damaged. For example, bruising on the back of the knee after running could indicate damage to a hamstring tendon.
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.
Consider the Causes
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 of unexplained bruising on your knee cap. In more serious cases, seemingly random bruising can be a sign of a blood-clotting disorder or blood disease, according to Mayo Clinic.
Treat Knee Pain at Home
Bruising and swelling in your knees should be treated with rest, ice, compression and elevation — the RICE protocol, as explained by Mayo Clinic.
Apply ice to your knees every 15 to 20 minutes, four to eight times per day, for the first 48 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.
Prevent Further Issues
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.
If you're running on uneven ground, consider walking down hills to decrease overall strain on your knee joints, as suggested by the U.S. National Library of Medicine.
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. There are many important factors to consider, such as width, insole and arch support, according to the American Academy of Orthopaedic Surgeons.
If taking preventative steps doesn't fix your symptoms, consult a doctor to rule out an underlying structural problem or medical disorder.