When you’re training for a marathon, you can strain a muscle almost anywhere. Most strains are in the hamstrings or calves, and happen when a muscle stretches really far or very quickly. There are a variety of ways this can happen, such as sprinting during a workout or landing funny on your foot when you run.

Typically, mild or moderate strains will heal in a few weeks with rest and icing for 15 minutes a few times a day. If swelling and pain continues, see your physician.