How Kate Walsh Stays Slim at 42

 Andreas Branch/ Press

Kate Walsh works hard to keep her bod at 42.

"The older you get, the more you have to work out," the Private Practice star told at the Neil Lane/Kay Jewelers party at Drai Hollywood Thursday night.

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Walsh does a Pilates-yoga-weight-training combo with trainer Juliet Kaska. "I am obsessed with Pilates. I love it, but she has other moves she puts in with it. It's a good recipe and keeps things interesting and fresh. And she knows the body like nobody's business. She is a body doctor!"

The actress also eats healthy "not because I want to. If I want to feel good and work the long hours, I have learned through process of elimination that I need to cut back on the caffeine and stay away from dairy and all the fun things."

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Still, Walsh refuses to deprive herself.

"But then I go out to dinner and I eat whatever I want and then I just pay for it the next day." Her fave splurge? "Delicious bread at restaurants. I am so boring, but that is what I splurge on."

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She doesn't always count calories when browsing the calorie-packed craft food table on the set of her ABC drama. "I do try to stay away, but every now and then I let myself indulge on the occasional doughnut. I'm not afraid to indulge on the glazed donut."

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