It's good that you mentioned that. There is a theory in regards to programing your body with good signs. Here is one simple method, it is call anchoring:

When ever you feel at your best choose a physical manerism to repeat every time. For example, when ever you feel great, grab your wrist as if you were turning a bracelet. Do this enough times ( or any other manerism that works for you ) until it almost becomes natural, except that, even over time it will become an unconsious physical manerism, it is indeed a manerism that you very consously created, and can use for when you are down. What happens is that your body will get the signal of when you are at your best and, well, it will influence you in a positive way... Just food for thought guys. I've used it and it helps, not 100% but it does.

gab