The 40-year-old star became a mom two years ago when twins Max and Emme were born.
Asked how she stays in shape, she said: 'I didn't work out for the first couple of months after Max and Emme were born. I was just concentrating on being a mom.
'Now I fit any exercise around my children. If I have time between feeds and the daily routine, then I will do it, but my babies come first.'