To boil it down – the race plan has two points:

1. Physiological – The best example of this is really creating a plan where in the first 1/3 of the race you don’t ‘shoot yourself in the foot.’ What does this mean? If you want to run a half marathon at 4:00/km then set a speed limit of 4:05-4:00 for the first 5km. For the most part, if you go out too fast, you will not run to your peak performance.
2. Psychological – When you have a plan in place, you can ‘focus on the process.’ So if 1/2 marathon plan is 4:05/km for the first 5km. 5-15km settle into a good rhythm, focus on mechanics and keep an eye on pace with a speed limit if 3:55/km. Last 6km ‘put the watch away’ and race, race, race! You can see here that the race in broken down into more digestible bites. So when you are 3km in and you think ‘shit, I have 18km to go’ you can change that to ‘okay, focus for two more kms and make sure to not break my speed limit.’