While the plank is an excellent core exercise, several other options can strengthen your core. You can do these bodyweight ...

Looking for an exercise that targets your core, hips and back muscles? You should do the bird dog exercise, which is great for improving balance, strengthening your core and promoting proper posture.

all you need is a yardstick or you can even use a broom handle just take the broom end off so coming down to the floor um you can prepare yourself if your knees don't like hard surfaces by all means ...