Stand tall with your back to an aerobic step or plate, gripping a dumbbell in your right hand. Maintain a tight core and flat back as you carefully place your right foot on top of the aerobic step or plate behind you. Ensure the distance between yourself and the aerobic step is not too great. Lean your torso forward, keeping a neutral spine and holding the dumbbell firmly directly in front of you. Bend the front knee as you drop the back knee, driving your hips back and down. Inhale as you do so. Ensure the front knee does not go over the toes and that the whole of the front foot remains in contact with the floor. Allow your thigh to come to parallel with the floor. Pause, then slowly return to the start position by extending the knee, but be sure not to lock it out at the top. Perform all the required reps on one leg before changing to the other, moving the dumbbell to the other hand as you do so.