Horse stride length and horse stride rate ie strides per second are two relative newcomers in the form analysis tool kit. Simon Rowlands has documented numerous times that strides per second remains fairly constant regardless of going but stride length varies according to going. If we accept that a horse’s ability to win a race rests on the equation of stride length x stride rate plus of course how long it can maintain that at or near its maximum then I am left wondering whether using stride length as a predictor of going preference might be a useful tool to assist our betting. My line of thinking here, and I admit this is early days, is that if all horses stride lengths shortens by x from good going to soft going but a horse with little exposed form runs on both these grounds and his stride shortens significantly less than the expected average despite running poorly on the soft ground (perhaps outlcassed or unfit), we could have a horse labelled as a soft ground disliker when in fact he is completely happy on it.
Let me also say up front that I have previously stated that going does not matter but when pressed on this I have expanded my opinion to state that overall when modelling it has limited benefit, probably because the market takes care of it. However that is not to say that in individual cases good bets cannot be made because of ground. I have had a few myself in the past but when modelling we are looking at overall contribution to a model and personally I have not found much value in the going.
Let us take a look at some stride averages (all horses 2017 to 2020) based on race distance and going. I have not accounted for class yet as I am simply wanting to endorse others opinion on stride length.
5f Firm 23.97
5f GF 24.73
5f Gd 24.62
5f GS 24.24
5f Sft 24.06
5f Hvy 23.08
5f St 24.29
5f St/Sl 23.98
The above pattern is replicated across all distances, the slower the ground the shorter the stride length. We can see that over 5f the drop from Gd to Sft ground represents a 2.27% drop in stride length. Now what if our horse Mudlark makes his first attempt at soft ground having run over Good ground and happens to run poorly but logs a stride length percentage change of say 1.5%. Could these horses have hidden preferences that the public is not only unaware of but also betting in the opposite direction when Mudlark next runs on soft ground.
This is an interesting area of research and your thoughts at this stage will be welcome in the comments below