Though all of the home gyms in our reviews do offer some type of ab workout, the best one for abs is the Wonder Core II. This unit includes a rowing function and twisting seat that focuses the majority of the workouts on your core, giving your abs the best workout possible. It adds in some other workouts as well, so you tone down or build muscle in your shoulders, arms, back, glutes, and even your legs as you do those ab workouts for a full-body experience.