Ab rollouts work the entire spectrum of ab muscles, ranging from the top all the way down to the lower abs. When your arms are fully extended on the ab rollout it will also work your lat muscles which are on your back, right under your arm pits.
When you first start off doing this exercise, you might want to try the ab wheel. It’s a plastic wheel with two handles on either side. You probably know what I’m talking about. They weight just about nothing, so it makes it easier to do the exercise. Also, if you’re a beginner, it’s probably a good idea to go in a smaller range of motion.
When you want to make the exercise more difficult you can grab the bar that I am using in this video. It’s smaller than a olympic sized bar so it weighs less. Gradually add weight and increase your range of motion until you can roll all the way out with your hands directly over your head.
Keep progressing so that eventually you will be able to do this exercise on the olympic sized bar. The more weight you have makes it harder by using momentum to work against you.
In the video I also forgot to mention…..It’s probably a good idea to have something soft under your knees. After a few sets of these, your knees will be rubbed raw. Believe me, I’ve had first hand experience. A yoga mat or something similar will work just fine.