Using an ab roller is not necessarily better than doing crunches. Ab Roller is complimentary to doing ab crunch exercises, so it’s best to combine them for a complete ab workout.
Whereas crunches work the middle and upper abs without much load or resistance, using an ab roller works the entire ab muscle group – upper, middle and lower abs while adding the additional weight of your body for more “load” and resistance through the move.
For best ab workout results, use crunches at the beginning of your workout to warm – up and focus on rep volume. Finish with lower reps on the ab roller focusing on proper form. Mix your workout up even more with dozens of ab and core workout moves with an advanced ab roller with multi-directional technology like ABLE by Fitness hardware.