Doing ab wheel exercises is an effective way to flatten your stomach and tighten your core. Using a regular ab wheel that is just a wheel with a rod through it will limit the number of exercises you can do. I prefer to use an ab wheel that I can optionally strap my feet into. The one I like the most is the Power Wheel by LifelineUSA.
I tried to list the exercises in order of difficulty, starting from beginner and going to advanced. I put in parentheses whether the exercise requires you to hold the ab wheel with your (hands) or have it strapped to your (feet).
Since I have not seen any other products that enable you to strap your feet to an ab wheel, the feet related exercises are unique to the Power Wheel and I credit LifelineUSA and the makers for them.
Isometric Pushup (feet)
With your feet strapped to the wheel, hold a pushup position. Make sure your back and legs are straight. Focus on your form, keeping everything straight and rigid.
Roll Out (hands)
With your hands on the wheel handles, and your knees on the floor, close together, roll out with the wheel as far as you can. Ideally, you’ll want to roll all the way out so that your chest almost touches the floor and your back and legs are in a straight alignment.
Then, pull the wheel back in to the start position, with the wheel right in front of you. Never pull back in with your butt and cheat the exercise. If your knees and hips create an arrow, with the head at the hips, this arrow should never point backward, always pointing straight up in the starting position and then pointing forward when you perform the exercise.
When you roll out, try not to arch your back as you may put way too much emphasis on the back and then your core is not doing as much of the work. Round the back a little, but always keep your arms straight.
With your feet strapped to the wheel, assume a pushup position. Keeping your arms and legs straight, pull your feet towards your hands; your butt will naturally pike up.
After you have pulled in as much as you can, hold for a second, then reverse the movement, pushing your feet back out to the push up position, without bending your legs or arms.
Of all the ab wheel exercises done with the wheel attached to the feet, the pike is my favorite. Your arms are getting a workout holding you body up, your core is doing a full body crunch, and your legs might get a decent stretch to boot.
With your feet strapped to the wheel, assume a pushup position. Now, starting walking with your hands. Walk forwards, backwards, and in circles. Keep your legs straight at all times. Only your hands and the wheel are touching the ground.
This simple exercise looks deceivingly easy, but you’ll soon realize just how much it works the core and especially the side areas as you lift each hand to take a step, shifting your weight to one side.
Moving forward and backward should be plenty in the beginning. When you’re ready, start circling objects like trees or chairs or snaking your way through the house.
Hip Ups (feet)
With your feet strapped to the wheel, lay on your back with your arms straight and flat at the side.
Now, pull the wheel in towards your back while pushing your hip up. Try to keep the motion smooth and in control.
This exercise is not easy at first. It can feel a bit awkward, it just takes practice.
Alligator Walk (feet)
This is just like the walking exercise except with each step, you do a push up. Your hands are offset from each other each time and are not on lined up equally like in a regular pushup.
Depending on how well you can do pushups, you may find your arms and chest working harder than your core, but it is a good exercise nonetheless.
Extended Roll Out (feet)
With your feet strapped to the wheel, assume a pushup position. Make sure your arms are straight. Push the the wheel further out behind you while keeping your hands fixed on the ground.
Your arms should start to be extended in front of you as the rest of your body is moving behind you. Go as far as you can and pull yourself back to the starting position. Keep your legs and back straight.
Standing Roll Out (hands)
Do a roll out, with your hands, but do it from a standing position instead of having your knees on the ground. Try to keep your arms straight throughout the motion.
This is intense and should not be tried unless you feel you are fairly adept at all the other exercises, and can do regular roll outs with ease.