How to do it: Grab a dumbbell and stand tall with the weight in left hand, core engaged, shoulders back, chest proud. Contract abs and lean to the left as you slide the weight down to left knee. Use ...

This quick circuit combines classic core movements with the stability ball, targeting your upper and lower abs for a ...

Pull in your abs. And as we say ... 15-second break, we're going to move on to bird dog on the stability ball. You may have seen this one before on the floor, but a little variety.

This makes ab workouts with a medicine ball more effective at burning calories ... work the entirety of your core while helping improve stability. The move also works your upper back, shoulders ...

and 24 stability-ball climbers, although my abs are burning and I'm out of breath at the end. It's a struggle holding a plank for even one minute and my whole body is soaked in sweat and trembling ...

A rock-solid core isn’t just about abs. These five full-body workouts build strength, balance, and endurance—proving your core is in peak condition.