Photo courtesy of: Trae Patton/NBC

Photo courtesy of: Trae Patton/NBC

In the years after he retired from professional football, quarterback Scott Mitchell saw the number on his scale rise about 10 pounds per year. His blood pressure numbers rose along with his weight, as did his triglycerides and the number of times he would stop breathing during the night due to his obstructive sleep apnea.

When Mitchell, who is 6-foot-6, passed the 300-pound mark, he essentially threw up his hands, hitting a point of acceptance with the way his body was: “It was a real emotional barrier for me,” he said. Noting that both of his parents and several other relatives were obese, he thought, “I’m just going to be a fat guy.”

Then one day last year, he tripped upon an online ad for auditions for NBC’s “The Biggest Loser,” a reality show featuring contestants who sequester themselves at a ranch where they work out with trainers, learn about nutrition and compete to lose the most weight.

The show’s new season was to focus on former athletes; Mitchell quickly filled out the online application. But while heading to the audition site in his home state of Utah, he was overcome with concerns about ridicule and ended up turning back without even going inside. About three weeks later, though, a casting director who saw his online application called him, and Mitchell agreed to go on the show.

On the first day of shooting in June, he weighed 366 pounds.

Six months earlier, on Jan. 4, 2014, Mitchell suffered the death of his 76-year-old dad, Bill, who long had dealt with obesity, diabetes and hypertension.

“I watched him die a horrific death over the past six years,” Mitchell said.

Mitchell thought about his future. “That’s literally what’s going to happen to me if I don’t do something about it,” he thought.

It was those concerns that persuaded him to shove aside any fear of embarrassment of being weighed and exercising on national TV in front of an audience of millions.

The show, which was taped from June to October and aired from September to the live finale on Jan. 29, “changed the course of my life,” Mitchell said. “It saved my life.”

His struggles with weight stretched back to his playing days. After each season ended, he’d eat whatever he wanted and gain about 20 pounds during the off-season. Then, he’d work out really hard to prepare for the next season, aware that if he went over his assigned weight at Thursday morning weigh-ins, he would get fined on a per pound, per day basis.

That kept him in shape through 12 seasons in the NFL, playing for the Miami Dolphins, Detroit Lions, Cincinnati Bengals and Baltimore Ravens.

Photo courtesy of: Trae Patton/NBC

Photo courtesy of: Trae Patton/NBC

After the father of five retired in 2001, he kept active for a while playing basketball with friends, but over time he stopped making exercise a priority and assumed a sedentary lifestyle.

He developed obstructive sleep apnea: He would stop breathing an average of 92 times an hour. His triglycerides were the highest ever on “The Biggest Loser,” he was told; he was pre-diabetic and had high blood pressure.

“Here I’m this world-class athlete,” Mitchell said. “To be told you’re one of the most unhealthy contestants we’ve ever had was a real blow to me.”

Over the 15 weeks he spent on the show, however, his blood pressure normalized as he changed his diet to nutritious foods in healthy portions and exercised daily.

How quickly his blood pressure normalized surprised even him. “It was really remarkable,” he said. (He was never on medication for high blood pressure.)

Though Mitchell did not win “The Biggest Loser,” he dropped a total of 120 pounds, going home at 246 pounds and meeting the Body Mass Index goal that had been set for him.

Photo courtesy of: Vivian Zink/NBC

Photo courtesy of: Vivian Zink/NBC

His endurance changed so greatly that he went from barely getting out of a chair without breathing hard to recently running more than seven miles home from an auto shop.

He now views weight maintenance as a lifelong commitment and something he must manage on a daily basis.

“My health is as good as it’s ever been in my life,” said Mitchell, now 47.

Pointing to the obesity, hypertension and diabetes that run through his family,

Mitchell said he wants to show his children it doesn’t have to be that way.

“I wanted to change the course of my posterity,” he said.

With that in mind, Mitchell said he returned from “The Biggest Loser” and started practicing what he learned at the ranch: preparing healthy meals that taste good, for the whole family.