Have you heard the one about the bariatric surgeon, the devout Mormon and the triathlete who walked into a mixed martial arts fight?

They’re the same guy, and if you didn’t see that coming, allow Dr. Steve Bang of Auburn to change your perception of an increasingly popular but still widely misunderstood sport.

“At some level, it’s something that I’ve always done,” Bang, 46, attempted to explain after his first-round technical knockout of Matthew Hanning on Saturday night at Androscoggin Bank Colisee. “I love competition. That’s the biggest thing that drives me, at all levels in all different sports.”

Yeah, but Doc.

We all understand Bang’s proclivity for running the Boston Marathon and attempting to qualify for the Ironman Triathlon world championships because it seems so … healthy. And nobody bats an eyelash when the 40-something coworker with the 20-something physique mounts up for his twice-weekly hockey or softball game.

Why, then, do we struggle to understand why Bang is compelled to risk a brain that invested 8, 10, 12 years in medical school, or bent to gamble with hands so committed to giving others a new lease on life?

Ninety years after George Mallory’s alleged “because it’s there” dismissal of those who questioned his sanity for wanting to scale Mount Everest, we still discriminate against the toughest and most talented among us whose passions we do not understand.

We’re quick to decry certain behaviors as dangerous. Stock car racing. Skiing or snowboarding. Boxing or MMA. But life is dangerous, y’all. Loving unconditionally is dangerous. Eating, drinking and being merry are dangerous. Getting in your car and driving to work every day is the most statistically frightful activity in all of society. It’s a choice we all make and a decided risk we all overlook.

And perhaps no speed bumps in our lives are more hazardous to our health than midlife regrets, or preoccupations with what might have been. Bang was a high school wrestler of some renown before joining the team at Brigham Young University in Provo, Utah, as a walk-on.

“That first year I broke my ankle,” Bang said. “Then I served a two-year mission for my church after that, so I never got back to it.”

We interrupt these dreams to bring you a blessed life, a growing career, and an expansive, All-American family.

The Good Doctor and his brood moved to Maine six years ago and were astounded to learn that the local high school, Edward Little, didn’t have a varsity wrestling team. Bang’s four oldest boys — Steven, Sheldon and Skyler Bang and adopted son Conner Murphy — made the 45-mile round trip to and from Oxford Hills every winter afternoon to fill the void.

Upon achieving adulthood, each made the transition to the amateur MMA cage, sanctioned by New England Fights. Predictably, the dormant competitive flicker in Dr. Bang’s mind grew to an inferno.

“I would come and watch them, and that would just get my blood going,” Bang said. “They gave me the impetus. I don’t think I ever would have took it upon myself to go out and explore the MMA side of it. I credit my oldest son, Steven, for that. The rest of his brothers and myself, we just kind of followed after it.”

Steven thought his own foray into the NEF hexagon would be a one-shot deal. Saturday’s unanimous decision loss to Jason LaChance was his sixth fight.

“We’ve always been wrestlers in our background, and it’s just another way to do that,” the eldest son said. “He’s seen us fighting. He’s one of those guys just like us who wants to go out and try a lot of things. I think he got amped up when he saw us.”

Ah, yes, try a lot of things. Let’s take inventory.

Bang completed the 2014 Boston Marathon in just under 3 hours, 9 minutes. That qualified him for a return engagement. Also in 2015, he will represent the United States in his age group at the Olympic-distance world triathlon championship in Chicago. And there is an annual race in Lake Placid, N.Y., at which Bang hopes to clear the elusive qualifying threshold and earn a spot in the Ironman Triathlon Worlds in Hawaii.

You might also know Bang as a co-conspirator with fellow surgeon and neighbor Jamie Loggins in what is arguably the region’s elite Christmas light display each year on Vista Drive.

All these Renaissance man qualities, however, are a far cry from getting your arms and legs bent at angles the Good Lord never intended, or swinging at an opponent’s temples with gloves not much thicker than the ones you use while shoveling the driveway.

“I’ve never seen him throw a strike before in his life,” Sheldon Bang said of his father. “It’s always been wrestling. He had zero knowledge before this, and he wins with a TKO.”

Every doctor knows the importance of continuing education, and Bang is no different.

In addition to training with instructors Travis Wells and Jesse Erickson at Central Maine Brazilian Jiu-Jitsu, Bang attended a striking seminar taught by Bangor sensei Chris Young.

“The first time I hit anybody was two months ago. That has been a challenge for us. It’s been a lot of fun learning that,” Bang said. “I studied anything I could just to figure out how to do it.”

How long before discretion outweighs the power of the dream?

Ah, there we go again, making presumptions. Let’s not forget that boxing’s current heavyweight champion, Wladimir Klitschko, is 13 months shy of 40 and holds a PhD in sports science. Our predeterminations about who should and shouldn’t be doing this stuff are badly dated and misguided.

“I would absolutely love to do this again,” Bang said. “The biggest challenge is just going to be time. With everything else that’s going on this year, trying to fit it in.”

For men at the crossroads of life, there are far worse compulsions than the need for an adrenaline rush or a religious approach to health and fitness.

Have you heard the one about the physician who’s undefeated as an ultimate fighter?

Whether you’re a middle-aged sportswriter on your own educational and fitness journey, or an impressionable teenager watching from the bleachers, he’s a hero. No debate or second-guessing necessary.

Kalle Oakes is a staff writer. His email is koakes@sunjournal.com. Follow him on Twitter @Oaksie72.