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OTRC: Jillian Michaels and Bob Harper talk 'Biggest Loser,' tackling childhood obesity (Video)

Jilllian Michaels and Bob Harper talk about the 14th season of 'The Biggest Loser,' tackling the issue of childhood obesity. (NBC)

Jillian Michaels and Bob Harper of "The Biggest Loser" are back, and this time, they're tackling the tough issue of childhood obesity.

Michaels, 38, and Harper, 47, gushed about the new season of the hit fitness series, which debuted on January 6, and the sensitive issue that they're set to tackle.

"This season on 'The Biggest Loser,' not only do we have Jillian Michaels back - which we are extremely excited about - we are tackling childhood obesity," Harper told OTRC.com at the NBC press tour on January 6. "What better show than 'The Biggest Loser' - we have transformed so many adult lives, we are just trying to make a difference when it comes to working with children."

The show, which is now in season 14, features overweight teenagers rather than adults. Michaels, who left the show in 2010 for what would be a 2-year absence, explained that the youth participation and format change were what contributed to her decision to come back.

"They bring innocence - they're a breath of fresh air," Michaels explained.

"Their eagerness to learn really came out in all their behaviors," Harper continued. "That was really refreshing. On our show, with the kids, we're never going to have them compete, they're not going to get weighed in, it'll be nothing like we are with the adults. I mean, it's about uplifting our children, it's about getting them to be more active, have more fun, those really hard conversations are for the parents ... it all starts from home, we really do believe that."

Michaels had announced her departure from the show in December 2010, saying she wanted to take a year off to bring home a child and focus on her charity work. In May, Michaels brought home a 2-year-old girl from Haiti and her girlfriend, Heidi Rhoades, gave birth to a baby boy.

Throughout her time on the show, the trainer has been known for her tough attitude towards the contestants as she helped them shed the pounds and get into shape. When asked if becoming a new mom has softened her demeanor, the trainer had a pretty definite answer.

"No," Michaels said. "I am exhausted - it's just - the sleep deprivation has made me like ... my fuse is like, this big."

"This woman came in after being away for 2 seasons - she is sweet, loving, and sensitive with her kids, and then she leaves her kids in the dressing room with her friends and then just goes to work in that gym and terrorizes those poor people," Harper continued. "She lets out all of her frustration."

Michaels worked as a fitness trainer on "The Biggest Loser" on and off since its 2004 debut. Ratings had started to decline in early 2010, although the previous 13th season, which ended in May and featured trainers Harper and Dolvett Quince, saw a small boost.

Michaels first left the series in 2006, then rejoined in the following year. She launched a short-lived spin-off show, "Losing It With Jillian," in 2010. After her second departure in 2011, she joined the talk show "The Doctors" for a short stint.

In July, reports said Michaels had asked to return to "The Biggest Loser." On her Facebook page: she told her fans, "I've just heard of the rumors regarding me going back to 'Biggest Loser.' This is 100% untrue. I respect the show and wish it well but have NO intentions of returning." It was announced in September that she would be returning for the show's 14th season.

The show airs on Monday nights at 8 p.m. ET on NBC. Watch a clip from "The Biggest Loser" season 14 below.

Reporting by Pamela Chen, correspondent for KABC Television's entertainment show "On The Red Carpet" (check for local TV listings).

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