Yesterday, Rio’s wife posted a boomerang video of herself in a neon green bikini on Instagram to mark the release.
She excitedly captioned it: “Ahhhh. The day is finally here my book is out.”
“Fitter, Happier, Healthier…. how you can become all 3.”
Kate and her new husband are currently on holiday after heading to an exotic location to spend Christmas in the sunshine.
The couple are with Rio’s three children Lorenz, 13, Tate, 11 and Tia, eight.