There are many different was or techniques to overcome dark thoughts when running a race, a long or a fast run. I speek mostly from my own perspective and what helps me.
Most important is to mentally prepare yourself for the race. You'll find more on the topic in the previous episode of The Happy Runner. If you are well prepared, chances are that you may not drift away into the dark.
At the end of this episode I also give my thoughts, why we get dark thoughts during races.
If you want to get more tips or you need a training plan for yourself you'll find all of it and more at the Run and Smile webapge