For most fortysomething women the prospect of slipping into a bikini alongside a young swimwear model would be a little daunting. But Jennifer Aniston, as you can see, is no average fortysomething. In her stunning hot pink two-piece, she was more than a match for her much younger co-star. The 41-year-old actress showed off a flawless figure as she peeled off to shoot scenes for her latest film, Just Go For It, in Hawaii last week.

With her was swimwear model Brooklyn Decker, 23, the wife of tennis star Andy Roddick. But perhaps Miss Aniston is not as naturally confident as she seems. She began a gruelling training regime after hearing she would be starring alongside Miss Decker.She has flown her personal trainer Mandy Ingber over to the island to help her get in shape. The pair see one another five times a week for punishing 80-minute gym routines that include yoga, martial arts and running. As well as power-walking twice a day, Miss Aniston is said to be a fan of Budokon - a martial art-based exercise.