Lie facedown on the floor with your legs straight and your arms next to your sides, palms down. Contract your glutes and the muscles of your lower back, and raise your head, chest, arms, and legs off the floor. Simultaneously rotate your arms so that your thumbs point toward the ceiling. At this time, your hips should be the only parts of your body touching the floor. Hold this position for 60 seconds, then rest one minute. Repeat three times.
Source: Men's Health