Sit upright in a shoulder press machine, squeeze your shoulder blades together and place your heels on the ground directly underneath your knees.
2. Keep your head, shoulders and butt in contact with the back pad at all times.
3. Grab the hammer grip handles, flex your abdominal muscles and extend your arms overhead by pushing through your palms.
4. Once your arms are fully extended, pause for a moment and slowly return to the starting position.