To do the exercise, lie facedown on a mat with your arms by your sides and your legs straight behind you. Next engage your glutes and lower back muscles to lift your legs off the floor while simultaneously lifting your head, chest, and both arms up off the mat toward the ceiling. Hold this position for a 3-count. Then relax as you return your legs, arms, chest, and head back to the mat. That's one rep. Continue 3-count lifts for 30 seconds.
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