The 28-year-old personal trainer, who is currently guiding a team of four young women towards weight loss in the Australian reality TV show, said that she sometimes finds it difficult to identify with her contestants.
Hall told The Age that fitness has always been an important part of her life because her father was an Olympic taekwondo trainer, saying: "I have memories of waking up early and going for a run with dad. We'd get home and the juicer was always buzzing. It was built into our lives, so it was odd to join The Biggest Loser and meet people who thought that wasn't normal."
She revealed that her training sessions in the show are "like interviews", saying that she likes to ask her protégées: "Why are you here, what do you want to achieve, what are you feeling now?"
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Hall continued: "They need to be honest. They need to admit that when they look in the mirror, they don't like what they see. I don't care what weight you are, I have days where I feel fat. I work on camera in white Lycra. I know I eat healthy but sometimes it's just irrational.
"I'm not a model. I don't look like a TV presenter - I've got muscles and a different sort of body type. We've all had the voice in your head that says, 'You're no good. You're going to fail.' Every woman knows what that feels like."
Hall revealed that she wrote her first novel last year, an action adventure called White Ninja, and recently signed a five-book deal with HarperCollins.
"'If I could write fiction full time, I'd happily hang up my Lycra," she said.
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