Before a recent practice, Minnesota United midfielder Johan Venegas adjusted a piece of clothing over his shirt that looked like a sports bra.

Below the base of his neck, a device about the size of a computer mouse nestled inside the tight black fabric. Forward Christian Ramirez calls the device, which every United player wears during practices, "a little hunchback."

They are actually GPS monitors. They track the total distance players run, some of whom log at least 10,000 meters — more than six miles, often with high-speeds stops and starts — in a game. They also show the amount of distance covered at high-speed running (five meters per second) and sprinting (seven meters per second).

The data helps the United coaching staff prepare an adequate workload for the Loons. That's been especially important of late. United, which typically plays one game per week, finishes a three-game, eight-day stretch with a match Thursday against New York City FC at Yankee Stadium.

Players see the data, too. After each game, three bar graphs hang in the United locker room. One tells each player the total distance he ran in a game. Another shows the distance covered by high-speed running. A third breaks down high-speed running by half. Only goalkeepers and a few players who find them too uncomfortable don't wear them in games.

When United coach Adrian Heath asks Jarryd Phillips, the team's head of fitness and sports science, how hard players worked, Phillips can provide a detailed answer from the GPS monitors.

"What does hard work actually mean?" Phillips asked.

Phillips said the data provide greater context to what Heath sees from watching his players. Knowing whether a player is working hard isn't difficult. Knowing how much ground a player covers in a sport that requires immense amounts of running, and how that is affecting a player, necessitates GPS technology.

"If you know a group of players well like I know this group, I don't need the GPS to tell who's worked hard and who hasn't," Heath said. "It's called sweat. It's called perspiration."

The GPS, tailored for sports, can tell coaches just how much the slog of a season wears on each player. Heath said if a pattern develops of a player running less in successive games, perhaps that player is more tired than he says or is injured.

Eight other MLS teams use the same technology, and most have players wear the devices during games, according to a spokesman for Catapult, which makes the monitors. Other teams, according to Phillips, track player movement with cameras placed throughout stadiums.

For younger players who have grown up with the technology, "It's like putting on their soccer jersey," Phillips said.

By making players wear the devices in games, United can consider the data under the changing dynamics of a season, such as injuries, a dense portion of a schedule and the type of playing surface.

After United played two games in a four-day span — on June 21 and last Saturday — Phillips said players' running output remained mostly unchanged, which meant they adequately trained and rested.

The GPS data has also given United coaches a greater understanding of why some young players have struggled this season. Phillips said there have been instances this season when some players made little impact in a game. These players posted some of the highest running totals, but their inexperience prevented them from playing smart.

"We can be a team that has the best stats running around, but if we don't have the ball and we're just running around defending it, what does that say about us?" defender Kevin Venegas said. "There's two sides of soccer. There's the physicality part, and there's the tactics and the beauty of the game."

Statistics on running around remain important to the Loons but also can be a reason to poke fun at teammates. Midfielder Miguel Ibarra likes to ask how 33-year-old Ibson runs more than the 26-year-old Ramirez. And Ibarra, 27, brags that no one runs more than him, unless they cook their numbers.

"If somebody beats me," Ibarra said, "someone must have done something."