If you work at a desk and your neck or upper back starts aching, you may have been given one of the most common posture cues in the world: “Pull your shoulders back.” It sounds sensible. But if your monitor is too low, your keyboard is too far away, or your chair height forces your elbows outward, pulling the shoulders back can actually make the posture feel more strained rather than more comfortable. The problem is that the shoulders are only one part of the picture. If your