Pals say that size 8 Coleen is relishing her new figure after losing the 2st she gained in pregnancy and building lean muscle thanks to 200 sit-ups a day and a program called the Tri Plan.
This involves rigorous 40-minute workout sessions four times a week and a strict diet which is said to re-train the body to burn fat instead of store it.
A source says: "Coleen's feeling more confident with her body than ever and can’t believe she has such great abs.
"She's worked incredibly hard over the past few months to not only lose weight but sculpt her body and joked how she wants to wear a bikini every day even when she gets home to Manchester!"
Coleen, who is also mum to Kai, six, and Klay, three, with footballer husband Wayne Rooney, 31 - has been working out with her trainer, Sam Witter, with a fitness routine combining metabolic and interval training, which changes every four weeks to keep challenging her body.
A pal says: "Coleen loves how varied her workouts are now, as she never gets bored and always feels like she's being pushed to her limit."
Read the full story in this week's Closer magazine - out now.
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