The secret behind Heidi Klum's toned body

  supermodel Heidi Klum  

German supermodel Heidi Klum has revealed that being active has helped her to maintain her body even after having three kids.

Klum, who had her third child last year, has made a grand comeback with a steamy ad campaign for apparel manufacturer Jordache, posing in nothing more than jeans.

The 33-year-old said that her kids keep her busy, and that she has started playing tennis.

"I have three children. That keeps you busy all the time. I work and we do a lot of things that are active. We work in the garden. We jump on the trampoline. I just started playing tennis with my husband. We climb in the tree house with the children. We go to the park and feed the ducks. We are always mobile," People quoted Klum, as saying.

Talking about Brett Ratner’s photo shoot, she said that the photographer has 20 to 30 people with him, so she had not much to do.

Klum added that all of them make her ‘look good’.

"There were 20, 30 people on set to take the pictures. He had a lot of assistants. So I don't have to do that much. They all make me look good," she added.