This move targets your triceps and works the abdominal wall to give you both flat abs and toned arms.
How to do it: Grab a pair of dumbbells and lie faceup on the floor with your arms straight above you, palms facing in. Bend your hips and knees 90 degrees. Keep your elbows pointed forward and about shoulder-width apart as you lower the dumbbells just outside your ears. Brace your abs in tight and lower your legs slightly towards the floor (maintaining the 90-degree bend in your knees). Slowly extend your arms straight up over your shoulders, as you lift your head and shoulders off the floor and bring your knees in closer to your chest.
Form tip: Be sure to keep your lower back pressed into the floor as you lower your legs in preparation for the crunch. If it's too tough to crunch up during the extension, do the move with your head and shoulders resting on the ground.
60-second cardio burst: Repeat your favorite cardio burst (jacks, running, or jumping rope) for 1 minute before repeating the entire circuit again.