Why you should make your executives sweat

July 11, 2012, 2:43 PM UTC

FORTUNE — At a Wharton leadership conference last month, Deloitte’s managing principal of talent development, Bill Pelster, was showing off his company’s new leadership school in Westlake, Texas, called Deloitte University. A key piece of real estate on the $300 million facility, he said, is DU’s 12,000 square-foot fitness room, called “DFit” for short.

DFit is not just an amenity. It plays a key role in Deloitte’s training programs, Pelster says. Some of the university’s programs for top executives require participants to wake up at 6:00 in the morning and hit the gym before starting the leadership training part of the itinerary. “The intent is to get them into a good sweat,” Pelster says, and also expose them to techniques for working out when they travel. At first, the leaders might complain about the early wake-up call, but most of them say, in their feedback after the program, that the fitness portion should definitely stay.

So people enjoy hitting up the elliptical before working their grey matter, but does exercise actually make people better leaders? There’s evidence that it does.

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It’s an extreme example, but General David Petraeus (who currently heads the CIA) reportedly said that physical fitness was the most important trait for good leadership, according to author and entrepreneur Charles Garcia’s Leadership Lessons of the White House Fellows. Granted, Petraeus, who was then the commanding general of the Multi-National Force in Iraq, led his troops through a 75-minute daily regimen of push-ups, pull-ups, and wind sprints designed to push the group beyond the point of exhaustion. Most of us could not keep up with that routine.

But you don’t have to train under Petraeus to benefit from his strategy, which is to cultivate teamwork and toughness by putting people through a rough situation together. Leaders tend to emerge from such situations. It’s something that admissions committees have known for a long time — if you want to be a Rhode’s Scholar, for example, athletic experience is a mark in your favor. Having played sports is a good indicator that an applicant has enough energy and discipline to hack it

That’s because exercise that pushes a person’s limits has the added benefit of showing their true colors. Anyone can seem collected in an air-conditioned office, but who still behaves like a team player when they’re sweaty and hopped up on lactic acid? Those people might also have some of the skills to haul everyone through the next corporate crisis with some class.

But most of us don’t have the time or brute strength to go through a basic training routine every morning. Even so, the simple act of scheduling regular workouts can help develop good leadership traits. According to the Mayo Clinic, 30 minutes of exercise a day for three days a week will release chemicals in the body and brain to help boost the immune system and stave off some effects of depression, certainly a drain on a person’s ability to think clearly and work well. There’s also a growing body of research that exercise can actually help generate new brain cells, improving memory, and perhaps delaying the effects of diseases such as Alzheimer’s.

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“Being in professional services, we work incredible hours,” says Pelster. “We also tend to travel a lot. The individuals who can do that and still exercise, they can handle the pressure of this life for the long-term.”

Software company SAS modeled its leadership course after the Human Performance Institute’s “Corporate Athlete” training program. SAS’ course is called “Leadership and Energy for Performance,” or LE4P. It’s a 90-day intensive training on how to manage energy to lead effectively. At first, the program was only open to top SAS executives. Now it’s trickling down the organization; about 50 SAS employees have completed it so far and many of LE4P graduates have become somewhat evangelical about the experience.

They seem super energized, and fitness plays a big part in that, says Chris Tunstall, part of the talent management and leadership development team at SAS. “The days that they work out, they’re much more productive, they’re much more focused.” Another benefit is, “they come out of their comfort zone, [then] they can take that mental toughness and put that in a business situation,” Tunstall claims.

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It makes sense. To harness the motivation to buckle down and sweat, you’ve got to think long-term. You’ve got to shed the security of your corporate casual gear, don your less-flattering workout clothes, and prepare to be out of breath for a while. The only way to do it is to know that it will pay off later in the day with more energy post workout, and also long-term, with physical attributes like, say, some good-looking muscle tone.

As we all know, it’s rough out there in the business world. The more we can do to survive a good ass-kicking, the better.