Strava, which fills an office in downtown San Francisco, is chock full of athletes making a product for other athletes. Many employees started as Strava users. Strava lets you record runs and rides from a GPS device or phone app, then upload them to track, analyze and share. It also has a leaderboard so you can compare your time to others'. Jordan Kobert holds a video conference in the office. The company allows flexible scheduling so workers can accommodate training. "The best meetings I have are ones where we take a walk," said co-founder and CEO Michael Horvath. "Movement in general is a theme here." You'll find cycling memorabilia, magazines and gear everywhere at Strava. Strava's online forum teems with praise for the product and support staff, shown here fielding questions from customers. Lunchtime runs and rides are common at Strava, where many employees are training for the Giants Marathon in September. Caitlin Looney, who does marketing for Strava, suits up for a group run. Employees say training together is a bonding experience that leads to greater teamwork and bonding in the office Strava is heavily staffed with cyclists, a fact obvious from the sculptures, toys and other items liberally sprinkled throughout the place. Michael Horvath (center) founded Strava in 2009 with college crew teammate Mark Gainey because the they wanted to create "a virtual locker room." Here, Horvath jokes with designer Kyle Yugawa (right) and engineer Ben De Jesus about a cycling video they're watching. Strava employees roll in after a pre-work ride. Despite its workout-friendly atmosphere, Strava employees can't bring their bikes into the office. The building owner doesn't allow it. They're locked in a storage room out back.

At Strava, the idea that “there’s always time for a run or a ride” is more than a motivational motto. It’s a core principle. The San Francisco startup is packed with Type A endurance athletes, people who run five or six miles at lunch and think riding 100 miles is a great way to spend a Saturday.

The 40 or so people shoehorned into a downtown San Francisco office have turned their passion into a business building a social network and performance-tracking tool for cyclists and runners. They work in an office packed with bike gear, and the meeting room is lined with dozens of bib numbers from races employees have competed in. It’s high-energy and hyper-competitive in a friendly way, just like the app.

“Through the sports we do there’s a whole lot of bonding outside of work,” Alex Mather, Strava’s UX lead, said. “It makes the arguments and discussions here a lot easier when you’ve ridden six hours with someone and gone through the crankiness of a long ride. We’re all very Type A, which leads to great discussions because everyone has opinions. We couldn’t survive if we weren’t Type A.”

Strava is more than surviving. It has received $16.1 million in funding and grown from six people to about 40 since its founding two years ago. It has added around 10 people in the past few months. Strava wouldn’t release specific data, but co-founder and CEO Michael Horvath said it is supporting “a few thousand” active users per employee. One day he hopes to hit 100,000 to 200,000.

It’s an ambitious goal, but fitness tracking gadgets and apps are hot right now. The industry is expected to ship 90 million “wearable” fitness trackers like the Nike FuelBand or FitBit by 2017, according to ABI Research. Forrester Research says wearables are the “next wave of consumer technology product innovation,” so it’s no surprise a company like Strava stepped into the market.

“The more people who own smartphones, and the more sensitive those devices become, the more data we have about our bodies and our environments,” Forrester analyst Sarah Rotman Epps said. “Fitness [tracking] is a natural starting point.”

The company’s growth has not been without challenges. Strava was sued last month by the family of 41-year-old William “Kim” Flint, who died while using Strava to track his speed down a fast descent in Berkeley, California. Strava also has been cited in the death of Sutchi Hui, a pedestrian hit and killed in San Francisco by a cyclist accused of speeding and tracking his time for Strava. Horvath had no comment on the lawsuit, and the company has kept mum about the cases.

Strava, like social Garmin Connect, Nike+ and others, lets you record workouts from a GPS device or phone app, then upload it to track, analyze and share. It shows, among other things, where you ran or rode, how long and how fast. You can compare your results over time and rank yourself against others via an online leaderboard. Those posting the fastest times on a particular road or trail win the title King of the Mountain, or KOM.

Strava was born out of a desire by Horvath and co-founder Mark Gainey to create a “virtual locker room.” The two men had rowed together on the Harvard crew team. After graduating and leaving the physical locker room behind, they decided in 2009 to create a site for avid endurance athletes. Strava is currently available as a free web and mobile app, with an option to upgrade to paid premium service. Upgrades are the primary way they’re monetizing Strava.

It’s common to hear people at tech startups say they’re building a product they love and use, but it’s especially true at Strava. If they didn’t work for Strava, they’d be using it. In what may be the best testament to how passionate Strava users are about the product, Horvath said many employees were Strava users before they came to the company.

“Our user base is a great place for finding people,” Horvath said. “If they’re using Strava, then they already know why we’re different. The key is not to say how fast are you, but how passionate are you? How much do you love what you do professionally and how much do you love cycling and running? Most of our staff is passionate about both.”

Strava’s user base is equally passionate. The company’s online forum teems with praise for the product and the support staff, along with suggestions for improvement – like, say, clearing leaderboards of impossible aberrations like someone running a 2:13 mile. Chris Holmes, a product development manager for Electra Bicycle Co., says Strava provides “a reason to push a little harder to go a little bit faster.”

“I've always been a numbers geek,” he said. “Strava takes it a step further, with the social aspect allowing me to see where I stand against other users who ride the same routes, along with how and where my friends are riding.”

Beyond the data, Strava’s vibrant social network is a major draw for users like Chris Phipps, who said more than 60 percent of the “200 or so” cyclists he knows in the San Francisco Bay Area use it.

“It's really easy for us to compare rides and see how much my friends are training,” he said.

Not everyone is convinced Strava is all that. Critics have even created terms like “stravasshole” to describe runners or riders who place their quest to be King of the Mountain above common courtesy. But the Strava team isn’t letting criticism slow it down. Everyone remains pumped and productive.

“It’s kind of that pinch-yourself job, where you say, ‘Wait – I get to ride for two hours, talk about bikes, come into work, and spend the next 8 to 9 hours talking about bikes?’” Mather said. “I just hope and pray that this lasts as long as it can.”

Photos: Ariel Zambelich/Wired