Most runners and other athletes have a love/hate relationship with their knees. They have a deep sense of appreciation for the mechanical wonder that is a knee joint, with its ability to propel a body forward with balance, speed, and power. Yet they despair over the joint's fragility and its ability to interfere with even the simplest forward motion when it is sore or injured. The good news is that a casual runner does not need access to a professional athlete's medical staff for knee pain treatments. The better news is that a few regular stretching and strengthening exercises can prevent knee pain and injuries and speed the recovery when runner's knee injuries do happen.