If you work in an office most of the day, your body is probably very familiar with the action it takes to hover over a keyboard or notebook. This rounded, shoulders-forward pose might allow you to get closer to your work, but it's imperative to take a break every now and then and stretch your chest so that your work slump doesn't become an all-the-time slump.
Try this simple chest opener:
From a standing position, roll your shoulders back. Clasp your elbows with your hands behind your back. If you have more flexibility, you may join your palms behind your back, with the fingers pointing upward. On the exhalation, roll the upper arms back toward the wall, opening the chest between the sternum and shoulder. As you open, keep the ribs relaxed; make sure they don't jut forward. Remember to stay grounded in your feet and center the movement below the navel. Relax the eyes, jaw, and tongue. Release on the exhalation. Change the arm on top, if you are clasping your elbows, and repeat.
Do this once every hour, and before you know it you'll stand up straighter and feel more balanced.