Why We’re Running Slower Than Ever Before

Surprisingly, mid-race selfies aren’t (entirely) to blame.

We may be obsessed with tracking our pace and comparing PBs, but a massive new study from the US says American runners are, on average, slower than they were 20 years ago. Researchers at RunRepeat.com analysed the results from 28,732 different races between 1996 to 2016 and found, compared to two decades ago, the average finishing time in America has dropped 39 minutes in marathons, 30 minutes in halfs, 18 minutes in 10Ks, and 8 minutes in 5Ks.

“Race finishers are significantly slower than they were last year, last decade, and also two decades ago,” confirms study co-author, RunRepeat site owner, and statistician Jens Jakob Andersen.

So what’s with The Great Slow Down?

Well, considering the number of people crossing the finish line has skyrocketed from five million in 1990 to over 17 million in 2015, according to Running USA, the most logical assumption is that we have more recreational runners signing up, dragging down the fast times of the serious and competitive.

And in fact, Andersen’s team looked specifically at the finish times of the 100th, 1000th, and 10,000th slowest men and women every year and found that tortoises have been slowing down at a faster rate over time than hares. “But to our surprise, the 100th fastest finishers are also slowing down,” Andersen added. “With more participants, one would expect more fast runners as well, which hasn’t been the case.”

Next best guess: the averages are brought down by more biologically-slower females or walkers. But the analysis shows men specifically are running slower than ever before too, and that the finish time of walkers has actually held steady over time.

So what’s the deal? The study was just a statistical analysis, so Andersen can’t say why for sure. But he does point to a correlation between rising obesity rates in the US and the slowing times. His team doesn’t have data on the health of all race participants specifically, but in general, “the heavier one is, the slower one is,” he said.

This could explain the lag in average pace, but doesn’t account for the slowing of the Speedy Gonzaleses.

One theory that might: perhaps people are less focused on hitting their PB and more on the experience of running itself these days. With the rise in general race participation, the advent of fun runs, and the cultural trend toward mindfulness and “running is my therapy”, it would make sense that there are more people getting into the sport purely for the enjoyment of pounding the pavement – at any pace.

“It would be interesting to see data on ‘why do you run’ over time and correlate it with finish times. 100 years ago, I doubt many people ran for fun, whereas today it’s more the case,” Andersen said. “On the other hand… with all [tracking] tools available, we compare ourselves a lot to others.”

If slow and steady is your jam, run at whatever pace makes you happy. But if you’re determined to land on the podium, it may be easier now than ever before.


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