New "Biggest Loser" Trainers: Brett Hoebel, Cara Castronuova Break Out

(CBS) "The Biggest Loser" has gained two new trainers. Do they have what it takes to whip the hit show's chubby contestants into shape?

Time will tell. But first, some introductions.

PICTURES: Brett Hoebel - New "Biggest Loser" Trainer

New trainer Cara Castronuova can certainly pack a fitness punch. She's a boxer, once ranked #2 in the nation, according to gossip site  E! Online. And given her hardscrabble background - her mother was killed in a car accident and her father died when she was 14 - she might not be too willing to put up with complaints from reluctant exercisers.

"Having a hard life made me stronger," she said in her debut on Tuesday night's episode, according to the site. "I'm here to bring back the fighter in each and every one" of the contestants.

If Castronuova is poised to punch contestants into shape, the show's other newbie stands ready to kick some butt. He's Brett Hoebel, described as a fitness guru with a background in kickboxing.

Trainer Bob Harper is expected to remain on the show. As for Jillian Michaels, she announced on Twitter last month that this season, the show's eleventh, will be her last.