Athletics is my favourite sport both for watching and for betting profits. Looking back over the last 38 years my best results have been in sprint events where my lifetime profit on stakes on major championships is over 100%.

In the 1960s the 100-yard sprint was only hand-timed to a tenth of a second, whereas today even the 10,000m events are electronically timed and the results declared to a 100th of a second – a degree of accuracy some 1,000 times greater.

This can lead to an obsession with times and in the men’s 100m most people just look at these to assess the athlete’s chances, but here is the way that I approach this event.