4. Overhead Dumbbell Press
The problem: Arching your back excessively, flaring your elbows, tilting your forearms inward, poor shoulder mobility.
How to fix it: Leaning backward is your body’s way of pulling your chest muscles in on the pressing action and compensating for a lack of shoulder mobility. Keep the focus on your shoulders by trying to stay bolt upright as you press.
Just as important, people often incorrectly perform the move with their palms forward and elbows flared out to the sides, as if holding a barbell. That position increases the strain on your shoulders, and thus your risk of injury. A much safer, more effective variation is to start with your elbows tucked and palms facing each other, pressing the weights directly above your shoulders.
Which brings us to another important point: If, when pressing the weights above your shoulders, you’re unable to bring your biceps beside your ears without arching your back or craning your neck, you shouldn’t perform the move at all. At least, not until you develop the shoulder mobility required to do it properly.