At lunchtime George puts on her run kit and heads-out for yet another run: 30+km days are hard to sustain without some significant hacks.

A popular view is that George's genetics are key to her performance. Our view is that it is not genetics, but belief in the importance of genetics, that causes others to be slow.

Here Dad and George discuss the importance of utility theory and economic modelling to enable training. If you believe you can't be fast and that monotonous training doesn't work then why do it? Of course, running slow - a lot - makes no sense. "I am not talented, I'll never be fast". It's a self-fulfilling prophecy that needs to be tackled whenever it is expressed.