Why do it? In addition to strengthening and stretching hamstrings and quadriceps, Butt kicks are considered midfoot strike drills. Doing these a few times per week can reduce injury while running by improving your running form.
Step 1: Set up your proper stance: Keep your knees close together and your torso upright. Do not lean forward.
Step 2: Quickly shift your weight to your right foot, bend your left knee and touch your left heel to your glutes, or as close as you can get. Lower your leg back down.
Step 3: Shift your weight to your left foot, bend your right knee and touch your right heel to your glutes, or as close as you can get. Lower your leg back down.
Step 4: Repeat this movement quickly, either moving forward slowly or standing still. Move your arms back and forth as with normal running. Focus on landing on your midfoot instead of your heal.
Image from fitday.com
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