The 29 year-old has told a UK magazine that her honed figure is down to doing “weights and interval training” with personal trainer Nick Mitchell.
The slim soapstar has also cut processed and junk foods from her diet, choosing lots of green veg and protein instead.
Although Catherine has dramatically transformed her shape, she insisted she maintains a realistic attitude towards her weight and doesn’t deprive herself completely.
“It’s how I’ve managed to keep the weight off this time around,” she said. “Fad diets don’t work.”
"I’m never going to be, or want to be, skinny”
“I’m happy where my body is now, I’m never going to be, or want to be, skinny,” she added.
“You’ve got to be able to have a bit of chocolate and enjoy yourself.”
The actress claimed: “I would never deprive my body of what it needs. Health and happiness are key.”
Catherine, who has recently split from boyfriend and personal trainer Sam Witter, thanked her fitness routine for her new-found happiness.
She said: “Everything has improved; my energy levels, my skin, my hair. And exercise raises endorphins, which make you feel happy,”
Catherine laughed off criticism from Twitter trolls after she posted pictures of herself in the gym: “I just thought the pictures were funny as I looked like a sweaty Betty!” She said.
“I only did it for my Twitter followers, as I get really sad letters from women who are desperate for weight-loss advice.”
“I’m into positive energy and anyone that’s negative; that’s their issue.”
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