Jillian Michaels: How I lost 55 pounds doing martial arts (photos)

The 5'2" Jillian Michaels, who once weighed 175 pounds, got fit
and healthy by overhauling her diet and doing karate. (Photos/Redbook)

The Biggest Loser star Jillian Michaels may be the picture of good health now, but the 5'2" fitness trainer was once a 175-pound couch potato!

Michaels, who stars on her own reality show, Losing It with Jillian, says a dysfunctional home life led her to an unhappy, sedentary youth of overeating and self-hatred.

'I HAD A THERAPIST BY AGE 5'

Jillian, who describes herself as a "really disturbed kid," began therapy at age 5.

"You know how kids have night terrors? Mine were really bad," Michaels, 36, says in the July issue of Redbook.

She recounts: "I thought sharks were coming out of the drain in the bathtub. I couldn't sleep at night, every night, waiting for aliens to come. I'm not kidding you: I. Was. Traumatized. And mom got me into therapy."

'I WAS TEASED FOR BEING FAT'

Michaels, 36, says she began a rapid downward spiral into overeating and gaining weight at age 12, when her parents decided to split.

"Being big as a kid was pure hell," says Jillian.  "I spent all of eighth grade in my classroom because God forbid I ever left. I was terrorized."

Michaels was stunned when her mom kicked her out of her home when she was 17. "They were kind of midlife-crisis-ing, and I was sort of the afterthought," Jillian recounts. "I became pretty angry -- no one wanted to deal with me -- so when I was 17, my mom was like, 'You're not living here.'"

Being on her own helped Michaels to become more independent and introspective.

"I learned a lot being on my own," she says. "I grew up. I had to make money. I learned how to make decisions that are right for me."

'KARATE CHANGED MY LIFE'

One of those "right decisions" was taking a martial arts class -- something which literally changed her life.

"Karate saved my life," she says. "It all stopped the day I broke two boards with a kick."

Armed with a newfound self-confidence and a fitter physique, Jillian became a certified fitness trainer, and auditioned for The Biggest Loser. After starring on the hit reality TV show since 2004, Michaels branched out by writing fitness books, releasing her own fitness DVDs and starring in her own spinoff, Losing It With Jillian. [see slideshow below]

Michaels, who's now helping other people transform their lives, confesses there are still lots of things she'd like to change about herself.

"I'm impatient," she says. "I'm demanding. I'm neurotic. I'm high-stress. High-anxiety. Perfectionist to the point of impossibility. Nothing's ever good enough. I'm never happy."

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