Tony Carvajal, a Certified CrossFit Trainer with RSP Nutrition , gets creative with these three core moves.
Lie flat on your back with your shoulder blades back, lower back pushed into the floor and abs tight. Make sure your legs are straight. Keep your arms extended straight overhead. Now lift your legs and arms at the same time. Keep your legs straight and lift as high as you can. Try to touch your toes with your fingers. Lower your back to the starting position. That is one repetition. Do 10 to 15 reps.
Variations: Try not touching your feet on the ground the whole time. Lift your legs and torso, and when you lower down, stop your legs at 45 degrees instead of setting them on the floor. Do 10 to 12 reps.
This is an advanced move, so make sure your core is strong enough to perform the exercise correctly.
Lie on your back with your legs straight, knees together and your arms extended past your head (similar to the starting position of the V-ups). Focus on drawing your belly button in toward your spine and pressing your lower back down into the floor. Contract your abs to lift your shoulders and arms a few inches off the floor. Keeping your knees together, lift your legs a few inches off the floor. From here, rock forward and backward without changing your body position. Try not to let your hands or feet touch the floor while rocking back and forth.
Variation: If the hollow rock becomes too difficult and your hands and feet start to collapse, try grabbing one knee with one hand. Continue holding the other arm and leg in the original position and rocking back and forth, swapping the hand and knee you're holding every interval.
This exercise also tends to be safe if you are recovering from a back injury.
Begin on all fours with your hands directly under your shoulders and your knees directly under your hips. Pull your abs into your spine. Keeping your back and pelvis still and stable, reach your right arm forward and left leg back. Don't allow the pelvis to rock side to side as you move your leg behind you. Focus on not letting the rib cage sag toward the floor. Reach through your left heel to engage the muscles in the back of the leg and your glutes. Return to the starting position, placing your hand and knee on the floor. Repeat on the other side to complete one rep. Do five to 10 reps.
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