Most of the power for pushing an object overhead comes from the legs. To transmit leg strength through the trunk and arms to the object being pushed, set the hips and tighten the abdominal muscles. Hands should be placed shoulder width apart with the upper arms aligned with the trunk. Squat slightly, then forcefully straighten the legs in a coordinated effort with the action of the arms (Figure C-13).
Figure C-13. Lifting overhead