If you took a tumble during a run, you probably know the cause of those swollen knees or ankles — you probably strained or sprained the muscle. However, sometimes the cause of the swelling can be a bit more mysterious.
In most cases, swelling knees and ankles in runners are caused by fluid that collects in the cells around the joints or by repeated microtrauma to the joints. If it's painful or interferes with your workouts, head over to a sports medicine physician to get it checked out. If it's just unsightly and uncomfortable, try a few at-home treatments to get the swelling down and keep it from returning.
Start with Ice
Depending upon your experience of pain, you may not need to head straight to the doctor for a swollen knee or ankle after running. Start by icing the ankle or knee for 20 minutes at a time; this should reduce both the pain and inflammation associated with the swollen joint. After each icing, apply heat to the injured area for 20 minutes, as this increases circulation and the rate of healing. Additionally, if you are experiencing pain continually, you can take over-the-counter pain or anti-inflammatory medications.
Take a Break
Even if you're not feeling pain, regular swelling indicates that you need to take it easy for a bit. Swollen joints mean that some sort of inflammation is occurring, and your body needs recovery time. Take a week off, and then hit the trail to see if the swelling occurs. If your body seems to be OK, then gradually increase your mileage once again.
Preventing a Reoccurrence
Preventing swollen knees and ankles due to running starts with a 5- to 10-minute warm up before you begin running. Stretch the hamstrings, quads, calves and ankles to increase blood flow to the muscles and ligaments and decrease injury including swelling. Additionally, when you finish your run, end by stretching again to increase the range of motion of your knees and ankles and reduce the risk of injury.
A Word of Caution
If pain and swelling in the knees and ankles after running does not go away with at-home icing, heat packs and rest after three days, consult with your doctor. In the event that a ligament tear or other severe injury is to blame, you may need more intense medical treatment. If you feel significant pain or find that it is impossible to bear weight on the injured leg, see your doctor immediately.