Utah MMA fighter Josh Tyler took on TV’s “Ultimate Ninja Challenge” — and it’s not what you might think. It definitely does not involve any teenagers, any mutants or any turtles.

“Our modern-day culture has painted ninjitsu as in this weird light of turtles and pizza — kind of this really hokey silliness, right?” Tyler said. “And the reality is it was a very serious occupation. These guys were very much like our modern-day special forces.”

The “Ultimate Ninja Challenge,” which premieres Sunday night on Discovery, is also very different from the similarly titled “American Ninja Warrior,” which features competitors attempting to complete a series of increasingly difficult obstacle courses. This is sort of like “Survivor,” only nobody gets voted off and the challenges are amped up beyond belief. The nine contestants are dropped in the wilderness of British Columbia for 24 days, where they have to survive ridiculously harsh conditions with no food, no water and minimal equipment.

“It was incredibly physical, being out and surviving for that length of time,” Tyler said. “It absolutely took a toll on the body — being cold, wet, exhausted for that duration. But then it also becomes very taxing on the mind. You start to doubt yourself and second-guess yourself.”

The eight episodes each feature a challenge based on a ninja principle. In the premiere, it isn’t easy for the contestants — divided into three teams of three — just to survive. Calling it grueling would be an understatement.

Tyler said his toughest challenge came in a later episode.

“Picture British Columbia in October,” he said. “It’s raining. It’s cold. It’s right on the verge of snowing. You’re soaked to the bone. You’re freezing. You’re exhausted. You’re starving.”

He had to chop a “massive log” with an ax “that may as well have been a sledgehammer. It was the dullest ax that they could’ve have come up.” Tyler swung the ax more than 2,000 times “and still didn’t make it through the log.”

Then he had to build a shelter, start a fire and stay awake through the night — because if he fell asleep, he'd get booted from the show.

“That was absolutely the hardest part of the whole thing,” Tyler said. “I really had to dig deep and push through.”

And yet he says some of his friends mocked him for signing on to the series.

“There were kind of snickers when I talked about it. A few people even made some jokes,” he said. “But I think when the show comes out, I hope that they'll look at the ninja in a little more serious and somber tone.”

It’s hard to believe anyone would snicker at Josh Tyler. When you talk to him, sure, he sounds like a great guy — friendly, personable and funny. But when you see the ripped MMA fighter in the cage, he’s sort of scary.

The Virginia native grew up a wrestler, competing in high school and college; he’s been competing as an MMA fighter for the past decade. He moved to Utah seven years ago to train at the Elite Performance gym in Sandy and spends as much time as possible in the wilderness. Which came in handy on “Ultimate Ninja Challenge.”

“It’s kind of the same thing as fight skills. If you don’t use it, you lose it,” he said.

He said he took on the “Ultimate Ninja Challenge” as a way to figure out his future.

“I’ve had success as a fighter” — he’s 16-5 — “but eventually we all come to a point where we can no longer continue to fight. It’s not a long-term occupation,” said Tyler, the married father of two. Should he continue to fight or devote himself full-time to his business interests, including Savage Gentlemen, which is based on the belief that there are two sides to men, and which sells a variety of products online?

“I like to think of myself as pretty mild-tempered, but there is a savage side to my gentleman,” he said. “It takes a lot to rile me up and get me going, but once that happens, I can flip the switch and be as savage as necessary.”

He can't give away much about how the filming went back in October, but Tyler did say, “The self-discovery that took place there — I just don't know that I would've been able to get that anyplace else.”

“Ultimate Ninja Challenge” premieres Sunday on Discovery — 8 p.m. on DirecTV and Dish; 11 p.m. on Comcast.