Advent of Alpha Day 12: Event Physics

For the next few days we’re going to get into the weeds of a sport I love, and have loved for a long time. If you’re not into horse racing, you might want to walk past, but I suspect there are parallels in other sports. In today’s article I’ll actually discuss such an example.

What is happening when a horse runs around Cheltenham?

I honestly think people abstract it all far too much. They look at the form, they look at how the horse has run on particular ground, or after X days away from course in the past if they can, and then try and translate it to today’s event and figure out whether it is well suited or not.

If I were to ask 99% of the people who bet on horses what they think about a runner at Cheltenham based on the Irish form, I’m not going to get the answer I’d give, which broadly is this:

The hill to the finish at Cheltenham is a rise of just under 12m in the last 440 yards, with Naas and Leopardstown around a 6m climb. Galway is 6.5m, but that’s after another 7m climb back to the dip 2 fences out.

If I see two horses having down comparable distances at these courses, I’m thinking in terms of the relative difference in the amount of kinetic energy needed to lift 550-600kg of horse plus jockey over that last half mile to quarter mile.

I think, based on all the people I’ve spoken to about racing over many years, I’m weird for thinking about the sport in terms of SI units of energy.

This is physics. Energy transfer. Resistance to that transfer in terms of not just total elevation, but elevation over distance, and after a couple of miles of exertion at a certain pace.

The going stick helps improve some of the thinking, but to be honest, not enough.

But I’m already probably thinking about this a bit harder than most.

And I suspect that there are other opportunities here to think about sport as not just a physical contest, but as a physics problem.

The parallel I promised was in relation to football. I had a lovely chat with a Director of Data over coffee in an impressive Premier League facility once where we discussed players as being like batteries with recovery rates: some players could take quite short periods to recover to the point of being able to sprint half the field, while others needed 3-4x the “break”. We presumed this should be observable in detailed tracking data. If so, the physics of the players fitness and ability to transfer energy - and recover energy - was quantifiably measurable. If we assumed the slower players were not just being lazy, we could start to make assessments about matchups and even find transfer targets.

I think this is not a novel thought in football any more. I think using physics to understand an event is a little novel in almost every other sport though, and I’ve never heard another bettor talk about it.

So please, talk to me more about this.