Planks, bicycle crunches, and leg raises on the “captain’s chair” are all great ways of working your core (and then some). But, to continue to see progress — and prevent boredom — you want to keep your muscles guessing, which means you need to constantly mix up your routine.
One amazing (and often neglected) way of training your core is to challenge your balance. The American Council on Exercise (ACE) recommends single-leg exercises; they require you to stabilize throughout your ankles, knees, and hips (so you don't topple over) and also strengthen your glutes while helping to ward off knee pain.
Ready to take the balance challenge? Here are four moves from ACE to get you started.