It depends on the Ab workouts themselves, technique used and any supplemental exercises that affect areas like the Illiacus, Psoas, Quadratus Lumborum, Lower Erector Spinae area, and the hip cuff muscles, (for want of a better term), the Piriformis, Obturator Internus, Superior and Inferior Gamellus, also including connective tissues as well.
Resting it may make it go away, with maybe some Icing in there, but if it's a technique issue, then resting it won't solve your problem, if you restart the offending exercise(s) and reignite the pain sensation(s) again.
