Luke Carlson wants to see his clients fail.

That is, he wants to see their muscles fail while working out.

The 36-year-old founded Discover Strength, a local fitness boutique, 10 years ago on the belief that people should work out less, but better, and he says pushing muscles to “momentary muscle failure” is the most efficient way to do that.

In an era saturated with niche fitness studios that draw cultlike followings through flashy branding and a plethora of promises, Discover Strength has increased its market share by focusing on customized strength training that relies on slow, steady exercises and leave clients shaking after each 30-minute sessions.

Tucked away on the ground floor of the Canadian Pacific Plaza building in Minneapolis, the company’s downtown facility epitomizes its no-gimmick philosophy. Its emphasis on efficiency appeals to busy downtown workers who want maximum results in the minimum amount of time. The trainers, working one-on-one or with a group of up to three clients, always wear ties and wingtipped shoes, and have earned degrees in exercise science.

These characteristics, along with Carlson’s insatiable appetite for exercise research that he applies to the workout regimen, is what the company’s believers say sets them apart.

Kristin Rowell, an attorney who works in downtown Minneapolis, first came to Discover Strength in 2007 when she realized she no longer had the time she needed to work out.

“I have exercised pretty much all of my life, but, frankly, it became too much time once I started practicing law,” said the 39-year-old lawyer. “I was looking for something that would take less time.”

When her friend told her about a gym where one can get a full-body workout in half an hour, she didn’t believe it.

“Then I had my first workout and I was challenged in a way that I was never able to challenge myself in the gym. I was pushing myself to levels that I never knew I could do, but he assured me it was all safe,” Rowell said.

That’s key.

There’s always a personal trainer there giving clients commands — don’t lock your knees, slow down, hold it right there, keep breathing.

Translation: no cheating.

Rowell has been going to Discover Strength ever since and has referred more than 120 people who became clients.

Carlson started the company at the beginning of the specialized, studio-fitness boom. Discover Strength, which has three Twin Cities locations with plans to add seven more over the next four years, has seen plenty of new boutique entrants vie for its customers.

In 2015, 42 percent of gym members in the U.S. belonged to a studio — or single-discipline — fitness center, according to a report by the International Health, Racquet & Sportsclub Association. The number of facilities offering small-group personal training, like Discover Strength, increased 24 percent from 2013 to 2015, while offerings for über trendy workouts, like barre classes, increased 141 percent in the same two years.

And yet the company has managed to see consistent revenue growth, 30 percent this year over last.

Its success, Carlson said, is in part due to a commitment to being the best at just one thing rather than chasing the latest fitness fad.

“We haven’t let ourselves be confused,” he said. “We want to be the Victoria’s Secret of fitness. We don’t want to be a department store.”

While Carlson has traveled the world to give speeches and to preach his fitness gospel, there is disagreement among researchers on the effectiveness of pushing muscles to the point of fatigue. Many agree though that if done sparingly and properly, it can be safe and effective.

That is why Discover Strength is by appointment-only and won’t let clients come without a 48-hour break between sessions.

That’s good because it’s not cheap. Each coaching session costs $55.

“We train a lot of lawyers and executives. They are our bread-and-butter clients,” Carlson said.

But they also have kids and retirees who use Discover Strength’s services.

“Our market share has only grown over the last 10 years,” Carlson said. “Research always shows that personal training produces the best results. We don’t even work out alone without one of the other trainers coaching us so that we can get the most out of our workouts, too.”

On the days when clients aren’t maxing out in a Discover Strength gym, they can safely do cardio training, such as running, walking or cycling, Carlson said.

Carlson is a marathoner and so is Rowell. In fact, she just completed her 20th and fastest marathon yet this year, clocking in at an impressive 3 hours and 19 minutes.

“I fully believe that’s because of Discover Strength,” Rowell said. “I’m totally an evangelist for the gym.”