Britney Spears ''doesn't mind'' working out.

The 33-year-old star admits she found it easy to lose her baby weight after giving birth to her and ex-husband Kevin Federline's sons Jayden, eight, and Sean, nine, but has recently found it more difficult to maintain her impressive figure.

She said: ''After I had Jayden, it was real easy for me to get back in shape. But five years later, I started noticing changes in my body. My hips are a little bit wider because I've had kids. So it was crucial for me to be continuous with my exercise.''

However, the 'Piece of Me' hitmaker has confessed she doesn't see going to the gym as a chore and has achieved her washboard abs without the help of a personal trainer.

Speaking to Women's Health magazine - in which she appears toned in a bright orange bikini on the cover - she said: ''Daily exercise is important for me both mentally and physically. I don't mind working out. Trainers keep you motivated, but I didn't have a problem being motivated.''

The blonde beauty, who likes to snack on ''any kind of fruit'' and treats herself with sushi and sweet tea, posted a teaser of her shoot with photographer Jeff Lipsky for the magazine earlier this year.

She wrote on Instagram: ''Amazing amazing shoot with @jefflipsky today! Been working hard this summer (sic).''