Self Talk your way to results
Im going to level with you. The secret is no secret. If you think positivley about winning the lotto for 365 days straight I can almost gaurantee you will not win. However, if you think you can run that marathon or finish that rep or eat a correct meal well your brain can make that a reality.
Research abounds indicating that positive self talk increases ones ability to exercise and this can be carried over into any life situation. People love routine and people also love self depricating. Many people fall into a patter of actually talking themselves down and this gets sandwiched into the subconsious. With postive self talk such as "I can do this" or "one more" or "your the best" or any other postive phrase you can push yourself to the next level. Try it some time. The trick is really just to break the cycel of all the times you have beaten yourself down and you don't even realize that it has become part of your person.
I won't bore you with all the research, you can google that on your own. What I will tell you is that I use this myself daily. Whether in the gym or pounding the pavement I am usually telling myself something along the lines of "do it" or "whatever it takes" or "one more". This works to push out one more rep or 100 yards or even to control mood or diet.
Give it a shot and get back to me here letting me know how it worked for you.