If you want to develop exceptional mental toughness, psychologists have plenty of suggestions. Most of them sound fairly pleasant, such as identifying and nurturing your passion and specific journaling techniques. But if you ask some of the folks who actually display otherworldly levels of grit--special forces soldiers, endurance athletes, chess champions--how they developed their toughness, you'll hear something very different.

The 4-Hour Workweek author and podcaster Tim Ferriss regularly brings these sorts of extraordinary athletes and achievers on his show and asks them straight up how they developed their capacity to take a mental beating and keep on fighting. Ferriss recently rounded up their responses for a post and the first thing that jumps out at you are their answers sound nothing like the gentle recommendations of productivity gurus and therapists. Here are just a few examples:

Jocko Willink, former Navy SEAL commander

Forget touchy-feely self reflection, Willink sounds more like he's channeling Nancy Reagan circa her famous "Just Say No" campaign. Here's how Ferriss sums up his advice:

"'Being tougher' was, more than anything, a decision to be tougher. It's possible to immediately 'be tougher,' starting with your next decision. Have trouble saying 'no' to dessert? Be tougher. Make that your starting decision. Feeling winded? Take the stairs anyway. Ditto. It doesn't matter how small or big you start. If you want to be tougher, be tougher."

Caroline Paul, daredevil

Paul has been a writer and a firefighter, but what she's most famous for is illegally scaling the Golden Gate bridge without ropes. How did she conquer her fear to climb 760 feet in the air with nothing to break her fall? Oh, just hit the delete button on fear.

"I am not against fear. I think fear is definitely important. It's there to keep us safe. But I do feel like some people give it too much priority. It's one of the many things that we use to assess a situation. I am pro-bravery. That's my paradigm," she told Ferriss.

In situations like her famous climb, she says, "I look at all the emotions I'm feeling, which are anticipation, exhilaration, focus, confidence, fun, and fear. Then I take fear and say, 'Well, how much priority am I going to give this? I really want to do this.' I put it where it belongs. It's like brick laying or making a stone wall. You fit the pieces together."

Amelia Boone, World's Toughest Mudder champion

The World's Toughest Mudder is an insanely punishing 24-hour obstacle course that only the truly brave (or borderline insane) would tackle. How did Boone develop the mental strength to actually win the thing? Her answer when Ferriss asked was very succinct and not at all pleasant: "I'm not the strongest. I'm not the fastest. But I'm really good at suffering."

These are only a few of the super achievers Ferriss gets to weigh in, but while a few of the other respondents offer more nuanced or slightly less extreme tips (don't go it alone, says General Stanley McChrystal, for example), this selection is pretty representative. And if these super athletes are right, developing exceptional mental toughness isn't something that comes from thoughtful reflection, meditation, or increased kindness (lovely and useful as those things are). Sorry, it's a lot harsher and harder than that.

Who do you suspect is right about extreme mental toughness, the psychologists with their gentle suggestions or the super athletes with their brutal ones?