Ab wheel rollouts are one of the toughest ab exercises. They require stable shoulders and core strength, but also build strength and mobility if you can successfully do them.
However, the wheel can feel daunting for many people who don't feel stable or secure while rolling in and out, so I have another option for you: the Pilates ab rollout. You can use a reformer bed, which offers a much wider surface area, or you could position your knees on a towel or sliders instead.
