Are you guilty of hunching your shoulders forward or hiking them up to your ears when you get anxious?

You're not only likely to feel tight and achy through the shoulders, but you are shortening and squeezing your intercostal muscles, making it more difficult to breathe fully. This has the flow-on effect of making you feel anxious and easily fatigued.

I know what most of you are thinking: My InterWHAT?

Intercostal muscles are the muscles between your ribs. They allow for the ribcage to expand and contract. You can stretch them out and really nail perfect posture by doing this:

Roll your shoulders back and slide your shoulderblades towards the spine. Not so that you're stiff as a board, but your chest should feel wider and more open
Lengthen through the neck and be conscious of keeping your chin parallel to the ground so that you're not dropping the chin
Regularly stretch the arms overhead and if you're sitting a lot, get up every half hour and move - even if it's just to the printer!

Try this stretch - you don't have to fully connect the palms, even reaching behind your back is a great chest opening stretch.