Sit-ups Lie on your back. Bend your knees and place your feet flat on the floor or mat. Position your heels about 1 to 1 1/2 feet in front of your tail-bone. Place your fingertips behind your head or cross your arms on your chest. Squeeze your shoulder blades together. Exhale then tighten your abs and curl up toward your bent knees. Do not pull on your neck. Keep your head in line with your spine, tilting your chin forward slightly as you come up. Keep the bottom of your feet, your lower back and your tail-bone flat against the floor throughout the exercise. Curl toward your thighs until you are in a seated position.
Mountain Climbers Assume a push-up position with your arms straight and your body in a straight line from your head to your ankles. Without changing the posture of your lower back (it should be arched), raise your right knee toward your chest. Pause, return to the starting position and repeat with your left leg. That’s one rep. Alternate until you’ve completed all your reps.
Modified V-Ups Lie face up on the floor with your legs and arms straight. Hold your arms straight above the top of your head. In one movement, simultaneously lift your torso and legs as if you’re trying to touch your knees. Lower your body back to the starting position.
Flutter Kicks Lie on your back with your legs together and extended out straight. You can place your arms out to the sides of your body with your palms down. Contract your abs and keep them tight throughout the exercise. Lift your legs off the ground about 6 inches. Lift your head and shoulders slightly off the ground. Raise on leg up a few inches and bring it back to the starting position. While it is on its way down raise the other leg up.
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