No single exercise hits your rectus abdominus (visible abs) better than the standing ab wheel roll-out. If I had to choose one ab exercise to train my abs for the rest of my life, this would be it… hands down.
I’ve tried pretty much every ab exercise and NOTHING offers more value-for-time when training to directly strengthen your abs. Make sure you master the kneeling ab wheel roll-out and the band-assisted or ramp ab wheel roll-out first. This exercise is advanced and if you can master the it then your abs are STRONG.