Scientists may have settled a long-standing debate in horse racing: Are thoroughbreds still getting faster, or have they reached their maximum speed?
Past studies examining this question concluded that racehorses have hit their biological speed limit, but researchers from Exeter University in the United Kingdom say those findings were based on data that didn’t tell the entire story. And although American Pharaoh wouldn’t stand a chance racing against 1973’s Triple Crown winner Secretariat, a new analysis of race times from 1850 to 2012 shows that racehorses, on average, are getting faster every year.
Getting the Whole Picture
In the latest analysis, scientists wanted to fill gaps they believe past studies failed to address. For one, the studies only analyzed winning times of a relatively small number of elite middle- and long-distance races. Other studies also didn’t factor in outside environmental variations, such as ground softness.
So researchers started by building a mathematical model to account for a variety of factors, including distance, number of runners, age, course and so on. Then, they compiled a massive data set of 616,084 race times ran by 70,388 horses between 1850 and 2012 in the U.K. Unlike prior studies, they didn’t limit their study to elite races, and their data set included short sprint races, as well as middle- and long-distance races. Scientists also accounted for number of runners, timing method, age and sex of the winner.
Going for Speed
After sending their collection of race times through the mathematical model, researchers found that horses were indeed getting faster, but speed increases were most significant in short races and tapered as the distance got longer. In other words, horses are becoming faster sprinters, but may have reached their max speeds in distance races. Here’s a look at how race times have improved over the years:
|Race Length||% Increase from 1850 to 2012||Average Annual % Increase||Average Annual % Increase from 1997 to 2012|
However, speeds didn’t increase consistently over time. Rather researchers found that speed improvements came in rapid bursts, rather than steadily year over year. For instance, times improved quickly from the late 1800s to 1910s, then remained steady until the 1970s. This finding could be explained by improved riding styles or other outside factors. Researchers published their findings Tuesday in the journal Biology Letters.
Scientists can’t say with certainty why horses appear to be getting better at sprinting but not at longer distances. Racehorse performance over long distances could be reaching an evolutionary limit. Or, researchers posit, breeders could be more focused on producing sprint horses. Changing jockey tactics over time could also affect race times, such as a new jockey posture pionerred by Lester Piggott three decades ago.
But if humans are getting bigger, faster and stronger every year, why not horses?