After giving birth to son Milo, 2 (with husband Royston Langdon), Liv Tyler was happy to be a stay-at-home mom.

But there was a downside to becoming domesticated. “I got so homely,” Liv, 30, says. “I was ravenous for things like doughnuts and cakes.”

That wasn’t part of the plan. After pictures turned up of the once svelte Liv looking quite plump, she came to realize, “I think the holiday is over.”

But unlike other celebrity moms, who seem to drop weight in a matter of days, Liv says, “I was not one of those women who just dropped pounds instantly when I was breast-feeding.”

With all the different diet fads and crazes, Liv wasn’t sure which way to turn. “I did a million different things,” she says. “I would be on a strict protein diet and then a raw diet, and then I would do colonies and fasting.” What finally worked?

Working out with her trainer David Kirsch and doing Pilates with Brooke Siler in New York (who has also worked with Kate Moss and Kirsten Dunst). Brooke says, “[Liv] came three times a week and also used a treadmill to get ready for her sessions so she could maximize the calorie-burning effects of the workout.”

Liv pushed herself and “preferred the [moves] that were stretchy and graceful but secretly liked the ones that worked her abs, even though they were hard,” Brooke says.

Liv’s vigorous filming schedule helped as well. “Filming was incredibly intense,” she says. “We were supposed to be out of breath in every scene, so I would run around the stage to achieve that. The weight just fell off me.”

In addition to the on-set cardio, Liv hired an on-set chef to prepare healthy meals so that she wouldn’t stray off track. This way she could munch on power foods like broccoli, spinach and fish all day long.

The gorgeous 5-foot-10 Liv is now healthier and fitter than ever. After being on and off diets since she was a model at 14, Liv explains, “The confidence that comes with taking care of my man and our child has taught me not to worry.”

Her trainer David has also become a dear friend in her fight against the bulge. Liv says, “Whenever I get insecure, neurotic or worried, he always brings me back and says, ‘You’re beautiful no matter what you look like.’”

Liv has always been gorgeous, but at a petite size 4, she is absolutely beaming! “I’m in the best shape of my life, I don’t feel like I’m dieting or struggling anymore.” [via]