Place your knees on the ground and your palms on top of a physioball. Slowly fall forward from your knees, rolling the ball forward with your palms, wrists and forearms. Keep your abs engaged and your torso straight as you move. When you've moved as far forward as you can go, tighten your core even more to roll the ball backward and return to the kneeling position. That's one rep. Move slowly and deliberately throughout.
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