The document discusses different types of stretching for runners: active warm-up, dynamic stretching, and static stretching. An active warm-up involves light aerobic activity to increase heart rate and blood flow before stretching. Dynamic stretching incorporates controlled movements that mimic sport motions. Static stretching is stretching a muscle to the point of tension and holding for 10-30 seconds. The document recommends a 5-10 minute active warm-up, followed by dynamic stretching before running for improved performance, and static stretching after running to increase flexibility without impairing performance.