The former Pussycat Doll is no stranger to hardwork, and that goes the same for her workouts.
She explains: "I have to feel fit and strong to do what I do. I have a trainer in LA to keep me motivated and we do a lot of circuit training and weights."
But it's not all hardwork and no fun, we all know that the key to staying in shape is enjoying what you do, otherwise you'll get bored and give up.
Nicole says: "Dancing has really transformed my body. I definitely recommend dance classes like Zumba, they're such fun and I don't feel like I'm working out.
"I choose exercises to match my mood. When I'm in the head space for Bikram yoga, that feels great to me."
Her top tip for a flat and toned stomach has to be an exercise ball she says.
"I love the results I get from using an exercise ball. I do sit-ups on them for my abs, and because it takes a lot of work to stay balances it really strengthens the core."
Femalefirst Taryn Davies