As fullbacks playing on the left and right wings for the San Jose Earthquakes, Shea Salinas and Nick Lima are expected not only to defend but also complement the attack. “No one works harder than us out there,” the two friends say to each other in training.

The GPS data collected from their STATSports devices objectively affirm that mantra. Lima is a little faster, but Salinas consistently covers more distance. Both log steep training loads.

That drive has carried over into everyday life this month. Lima and Salinas have joined front office employees in a step-tracking charitable contest. Organized by Earthquakes partner Avaya the competition aims to raise money for Doctors Without Borders.

With two days remaining in the monthlong competition, Salinas has taken 345,024 steps compared to Lima’s 314,680, a lead of more than 30,000 over his teammate. Then again, Salinas, who is 32, has three clear advantages over Lima, 23. Salinas has two young children (ages four and two) to chase and one home to remodel, which means tiling floors and all sorts of cleaning.

“You get a lot more steps on those days,” Salinas said. “I rarely get to sit down and take a nap. Not rarely. I never get to sit down and take a nap. So my watch is always counting, unlike Nick’s. Nick’s probably gets a little bit of rest in the afternoon.”

As if this point needed any emphasis, his son’s voice could be heard in the background of a phone call. Salinas reported that he was in the backyard, waving a flag around at his son’s request.

Both track their daily steps via Apple Watches and have synced their STATSports data as well. The two are among the few Earthquakes players to wear the trackers in games. Lima pays special attention to the number of sprints he makes in a game and the duration of those sprints, as well as top speed and total mileage. Salinas said he’ll run as many as 12,500 meters (7.8 miles) in a match.

“If I’m under 11,000 meters in a game, I know that, man, I probably wasn’t working as hard as I could have and wasn’t making as many runs as I could have,” Salinas said. “Sometimes, games dictate how much you run, but I like to be around that 11,000-meter mark every game.”

Salinas grew up running cross country and said he always wore a watch to keep track of his times, only back then it was a simple Timex rather than the Apple Watch and its FDA-grade heart monitor. He is cognizant of his age in this young man’s sport and has made additional lifting a priority—so much so that he said that his GPS has down his speed increase over the past few years.

“My body definitely takes a little bit longer to recover from a game than it used to,” Salinas said. “It takes me a little bit longer to warm up for a practice than it used to. But I’m just thankful that, once I do get warm and once I am recovered, I feel like I can still hang, if not beat, a lot of the young guys.”

Lima, on the other hand, is just starting his career. He was a nominee for both MLS Defender of the Year and Rookie of the Year in 2017. Back in January 2018, he received a call-up to the U.S. national team for a friendly, although he did not play in the match. He called the GPS data “very telling” from a macro level, allowing him to monitor his workload and react accordingly.

The two also compare their match data so that they have an objective measure of their exertion on either flank of the pitch.

“We always make it a thing for myself and him to be the hardest workers,” Lima said. “We’re always trying to push each other to do that. There’s definitely good that comes from it in the game in having the data to see after and know if our motivation toward each other is working.”

The steps competition has inspired some friendly banter as the two compare their steps and ultimately, they hope, some help for good causes. Not only are they raising money for Doctors Without Borders, but Salinas also wants the publicity to resonate with the members of Get Earthquakes Fit, a club program to encourage children to eat healthy, stay active, and do well in school.

“It just blows my mind how much little kids sit in front of screens these days,” Salinas said. “Part of my hope by doing this, some teenagers and some kids see that these guys move a lot more than even I do.”