Maybe you've heard that stretching before a run is a big mistake. Indeed, studies show that static stretching—holding a muscle in an elongated, fixed position for 30 seconds or more—could hurt performance if done before a workout (save it for after your run). But dynamic stretching, which uses controlled leg movements to improve range of motion, loosens up muscles and increases heart rate, body temperature, and blood flow to help you run more efficiently. Dynamic stretching is most effective when it's sport-specific. This prerun routine targets the muscles used for running. Start slowly, focusing on form; as the exercises get easier, pick up speed. Use small movements for the first few reps, and increase the range of motion as you go. Written descriptions of each exercise can by clicking through to the following video.

LEG LIFTS
Swing one leg out to the side, then swing it back across your body in front of your other leg. Repeat 10 times on each side. Feel wobbly? Hold onto a steady object.

BUTT-KICKS
While standing tall, walk forward with an exaggerated backswing so that your heels come up to your glutes. When this is easy, try it while jogging. Do 10 reps on each side.

PIKE STRETCH
Get in a "pike" position (hips in the air). Put your right foot behind your left ankle. With your legs straight, press the heel of the left foot down. Release. Repeat 10 times on each side.

HACKY-SACK
Lift your left leg up, bending the knee so it points out. Try to tap the inside of your left foot with your right hand without bending forward. Repeat 10 times on each side.

TOY SOLDIER
Keeping your back and knees straight, walk forward, lifting your legs straight out in front and flexing your toes. Advance this by adding a skipping motion. Do 10 reps on each side.

WALKING LUNGES
Step forward using a long stride, keeping the front knee over or just behind your toes. Lower your body by dropping your back knee toward the ground. Maintain an upright posture and keep your abdominal muscles tight.