Singer Fergie says workouts are essential for her as she enjoys eating.

The pop star, who shares son Axl Jack with Josh Duhamel, likes to keep her fitness regime interesting.

"Keep it interesting…I have (to do) treadmill, elliptical, bike and dance. I do the bands. I do it all. I have to work out because I love to eat. I had two Double-Doubles last weekend," quoted Fergie as saying.