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This exercise is best done when standing. Hold the barbell or dumbbells with a palm-forward grip, slightly wider than your shoulders. Hold the weight in front of your head, just above shoulder level. You can do this exercise while seated, although the seated version does not exercise your core as much. If you've had lower back trouble, stick to the seated version. Sit on a press bench with vertical support for your back. Keep your back straight and your feet firmly planted on the ground. Shoulder presses build muscle most efficiently as a high-weight, low-repetition activity. Begin with 2-4 sets of 4-8 reps each.

Summary:
Enter the starting position. Lift heavy.