The Russian twist is a great exercise to really work your obliques, or side abs. To do this exercise start seated with your back raised off of the ground and feet in the air about 90 degrees (you'll look like a V.) Rotate your arms side to side, touching the ground each time. For more resistance you can hold a milk jug or anything lying around the house for some added weight.
Unlike a regular crunch, the reverse crunch works your lower abs. Start off lying on the ground with your feet on the ground and knees bent. Curl your knees towards your face bringing your butt and head off the ground, but shoulders planted firmly. Bring your legs back to start and repeat!
While this exercise doesn't seem quite as obvious as a sit-up, it does work your abs (and legs too!) Your core is critical when it comes to stabilization and that's exactly what it is doing here. Start with your feet hip width apart and hands above your head. Then squat down keeping your hands above your head.
Bicycle crunches are an all-around great ab exercise because they work your entire core. Start by lying on the ground with your feet out in front of you and hands behind your head. As you crunch up one leg, bring the right elbow to the left knee. Alternate legs and arms with each rep.
V-sits are also great for stabilization. Start lying down and then raise your feet, back and head off of the ground, keeping your hands at your side. Crunch up, bending your knees so you form a V and slowly lower back down.
This exercise is a little more advanced because it uses your upper body and abs. First start out in a push up position. Go down for a push up, come up and rotate to one side, keeping one foot stacked on the other and raise your hand in the air. Roll back to plank, do a push up and switch to the other side.
For a simpler version get in plank position with your elbows on the ground. Roll to one side, again stacking your feet, but keeping your hand at your side. Roll back to plank and then to the other side. You'll feel your entire core start to burn!
This exercise is killer for those lower abs! Lie flat on the ground with your feet raised out in front of you about an inch and your hands behind your head. Cross one leg over the other then uncross. Repeat, alternating legs each time.
This exercise can be done from the floor or for a greater range of motion, you can lie on a bench with your legs hanging off. Lie flat on the ground, bring your legs up and bring back down. If you are on a bench, try to make them touch the floor each time.
Hello obliques! They'll love you for this move! Get in a side plank position on your elbow and bring the top leg and elbow towards one another creating a crunch motion. Do a few on each side.
Talk about core stabilization! Get in a plank position on your elbows, raise up onto your hands and extend the right arm and left leg outwards. Bring them back to center and then extend the left arm and right leg out.
Try doing this for the full length of three commercials, your abs will be burning! Lie on your back, feet flat and knees bent. Crunch upwards so your head and shoulders are off the ground. Lean side to side touching your feet on that side each time.
In order to have a strong core, you need a strong lower back too! Supermans are great for your back. Lie flat on your stomach with your hands out in front of you. Raise your arms and legs up and you can either hold it for a few seconds or drop down and go right back up.