Running USA has also found that 52 percent of runners today track themselves with some sort of GPS-enabled device, like a smartphone, a fitness tracker, or a specially designed running watch. This statistic has likely played a role in running’s growing appeal—the influx of easily available tracking information has lured people to the sport, and kept them going, by making it possible for anyone to see in real time how it’s affecting their bodies. These apps and gadgets allow people of all skill levels to run more strategically—and to stay motivated, which is very likely the biggest hurdle to becoming an after-work endurance athlete.

It’s a change that’s happened fairly quickly. The first GPS-enabled watch aimed at runners is just over a decade old; it was introduced in 2003 by Garmin, a GPS-technology company that initially developed products for the military. In 2006, Nike launched the Nike+iPod Sports Kit, which tracked runners’ distance and pace through a sensor inside a Nike shoe, connected to a receiver plugged into an iPod. It was a hit, but was quickly eclipsed by the iPhone: When the App Store launched in 2008, with MapMyRun as one of its first apps, just about anyone had access to the type of data previously only available to elite athletes.

“Run-tracking technology has traveled light-years in the past 25 years,” says Bryan Boyle, the gear editor at Runner’s World magazine. “Back then, to track distance, we either used the track or a pre-determined route using the car’s odometer. Maybe we used a Swatch to measure time.” Today, free smartphone apps give runners information on pace, distance, and elevation. If they upgrade to a top-tier watch, they can find out things like the number and length of their steps, their heart rate, even the estimated volume of oxygen they consume per minute and their vertical oscillation (the amount they bounce up and down on each stride).

All this information can act as a reward and a motivator for the runner. “It’s one thing to hear encouragement from a coach,” Boyle explains. “It’s quite another, however, to digest and appreciate—at a glance—progress made during weeks and months of running. Miles logged piling up. Pace per mile improving.”

In some cases, these reminders can make the difference between new runners pushing forward through an exhausting marathon-training program and simply giving up. “It has a self-reinforcing function,” says the sports psychologist and Temple University professor Michael Sachs. “You have charts and graphs to show your progress. When you’re meeting your metrics, it builds self-esteem, making you feel more competent and motivated to keep running.” Knowing that I’ll be able to see evidence of my improving distance and pace—and that other people will be able to see those numbers, too—has often been the thing that pushes me out the door. I doubt I’m the only one who’ll dash up and down the same block a few extra times to record exactly five miles rather than calling it in at 4.6.