Take a moment and pay attention to how you are sitting. If you are like me you are probably bent in a bit of an arch from the waist to your head and have your shoulders rounded forward.
Take a moment and feel the center of your torso, around the navel. There are a lot of powerful muscles in that area that are probably slack. If you tighten slightly, your back will straighten out and you will feel taller. Your shoulders might fall back on their own when you straighten your back, but if they have not, gently move them backwards. Now use the muscles in the back of your neck to hold your head up and make your neck strong.
Now take a moment and examine how you feel once you are sitting up straight. It never fails to make me feel more powerful and as if I can conquer the task in front of me. A lot of people tell you to stand up straight to look better, and they are right, when you hold yourself up you look more powerful. I think it is more important to remember that something as simple as taking a few minutes to make your back straighter can make you feel more powerful.
Next time you are feeling anxious and not quite up to the task at hand take a moment and stand up tall and strong. Sometimes just taking a moment to make the body feel stronger can do wonders for the mind.