Long-Arm Weighted Crunch
This abs exercise targets your upper abs. Lie on your back with your knees bent and your feet flat on the floor. Hold a light dumbbell in each hand and extend your arms straight back beyond your head. Now crunch your rib cage toward your pelvis, keeping your shoulders still and your arms straight. Don't generate momentum with your arms. Perform 12 to 15 repetitions.

Seated Ab Crunch
Sit on the edge of a bench. Grip the edge of the pad and lean back slightly, extending your legs down and away and keeping your heels 4 to 6 inches off the floor. Bend your knees and slowly raise your legs toward your chest. At the same time, lean forward with your upper body, allowing your chest to approach your thighs. Return to the starting position. Perform three sets of 12 repetitions.

Corkscrew
This abs exercise targets both the lower abs and the obliques. Lie on your back, with your legs raised directly over your hips. Your knees should be slightly bent. Place your hands at your sides with the palms down. Use your lower abs to raise your hips off the floor and toward your rib cage, elevating your feet straight up. Simultaneously twist your hips to the right. Hold, then return to the starting position. Repeat, twisting to the left. Do 10 repetitions to each side.

Weighted One-Sided Crunch
This abs exercise targets both the upper abs and the obliques. Lie with your knees bent and your feet flat on the floor, and hold a dumbbell with both hands by your right shoulder. Curl your torso up and rotate to the left. Lower yourself, finish the set on that side, then switch directions and repeat, holding the dumbbell next to your left shoulder. Perform three sets of eight repetitions to each side.

Kneeling Cable Crunch
Kneel facing the pulley and hold the ends of a rope attached to the high cable along the sides of your face. Bend forward, aiming your chest at your pelvis. Return to the starting position, then repeat the movement, this time aiming your chest toward your left knee. Return, then repeat to your right. That's one repetition. Perform three sets of eight repetitions.

Crunch/Side-Bend Combo
This exercise targets both the upper abs and the obliques. Lie on your back with your knees bent, feet on the floor, and hands behind your ears. Curl up so your shoulder blades are off the floor. Bend at the waist to your left, aiming your left armpit toward your left hip. Straighten, then bend to your right. Lower yourself to the starting position and repeat. Perform three sets of eight repetitions to each side. ABS6