What are the differences in these types of stretching and which is appropriate to do before and after a run? And, what muscle groups are the most important for runners to target when stretching? 

Running is a repetitive, high-impact movement. Stretching before a run helps warm up muscles, increases range of motion and can be beneficial in helping to prevent injury. But what type of stretching is recommended?

Static stretching is holding a stretch for a period of time. Because you are holding the stretch and trying to push the muscle to its maximum length, muscle fiber its stretched to its limit. It makes sense that you should use static stretching after a run when your muscles are already warm. 

Dynamic stretching is moving through a stretch – adding movement to a stretch, but not holding it for a period of time. Dynamic stretches are recommended before you run. Watch my video on dynamic stretching. I’m providing a few ideas to help you get warmed up before your run. Don’t forget to incorporate some static stretching after you run. 

Important muscles to warm up before you run: calf muscles, hips, quadriceps, hamstrings, iliotibial bands, piriformis, psoas, gluteal muscle, groin, spine stretches, and lower back. Happy stretching and enjoy your run!