You may have a sharp pain between the shoulder blades or a chronic feeling of tightness in your upper back. Poor posture, endless hours in front of a computer, and a lot of lounging on a sofa which is too soft, all contribute to these aches and pains, as does a condition known as kyphosis, characterised by a rounded upper back and shoulders. Too much overhead work at the gym, such as lat pull-downs, can lead to this as well. Here's how to counteract with yoga.