Jan. 14, 2013 at 10:34 AM ET
Nathan Montgomery's stay on "The Biggest Loser" wasn't a long one. Just two weeks after arriving on the ranch, the 25-year-old said "so long" to his teammates and his tough-as-nails trainer, Jillian Michaels.
It wasn't how Nate imagined his reality-TV weight loss journey would go.
"I really wanted to be there for the long haul," he admitted during a Monday morning visit to TODAY. "I think I just had a big turnaround mentally, working with Jillian, so I was really excited to be there a long time instead of leaving so early."
But as it turned out, he didn't need to be there for the long haul to make big changes. He started the show weighing in at 359 pounds and left it 25 pounds lighter. Since then, he's shed another 50.
That's a remarkable result for someone who fell off the treadmill -- more than once -- on his first day in the gym and then received some tough love from Jillian, who kicked him out of the gym for the rest of that day. But that take-no-nonsense approach is exactly what inspired him to keep going.
"Jillian is such an inspiring person," Nate said. "She really teaches you a lot about yourself, and how you push past mental barriers. I learned a lot from her that I'll carry on for the rest of my life."
And it's a life he now plans to share with his girlfriend-turned-fiancée.
"One of the reasons for me being on the show was that I wanted to feel like the man that she deserved," he said.
As "Biggest Loser" viewers saw in Nate's where-are-they-now segment last week, he met that goal and popped the question in front the cameras.
See how Nate's former fellow competitors continue to fare when "The Biggest Loser" airs Monday at 8 p.m. on NBC.
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