By InStyle Staff
Dec 17, 2011 @ 12:00 pm
Arun Nevader/FilmMagic

Can you believe Heidi has had four children?  Neither can we!  That’s why we just had to get the scoop on her runway-ready workout from celeb trainer David Kirsch.  Read on for all of Klum’s secrets, from post-pregnancy light yoga to intensely focused exercises you can even do while holding your baby!

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