Begin by positioning a pair of dumbbells a shoulder height with your elbows pointed directly forwards. Brace your core and keep your chest up. Bend first at the knees then at the hips, driving the hips back and down, inhaling as you do so. Lower with control until your thighs are parallel to the floor or deeper depending on your range, making sure your knees are pointing in the same direction as your feet and that your lower back doesn't collapse. Reverse the movement by extending at the knees and driving the hips forward. As you come back up to the standing simultaneously drive both dumbbells up overhead by fully extending your arms. Exhale as you do so. Repeat.