Want to know how celebrities really get buff and toned? The biggest Hollywood fitness myth is that they have great bodies because they have all the money in the world for personal trainers and professional chefs. While they may be able to afford these perks, they still have to do the work. Shape’s March cover girl, Jaime Pressly. “I’ve always exercised really hard,” says the 31-year-old North Carolina native. “I’m into the no pain, no gain thing!”

All that effort has paid off. Almost two years after giving birth to her son, Dezi, Jaime tops our annual list of the Sexiest Bodies in Hollywood.

Of course, Jaime’s allure goes way beyond toned abs. She also exudes self-confidence, a characteristic she finds appealing in others. Here, the Emmy-winning star of My Name Is Earl (and of the soon-to-be-released romantic comedy I Love You, Man) spills her secrets for getting sculpted and staying motivated—and dishes on what really makes a woman sexy.

Stay focused on a goal
Like a lot of first-time mothers, Jaime allowed herself to eat whatever she wanted while she was pregnant. “I gained 42 pounds,” says the 5-foot-4-inch actress. “That’s a lot of weight for mama!” After her son was born, she set a specific goal: to get back in shape in time for her 30th birthday party. “I needed to get in the gym and run on the treadmill and lift weights,” she says. By the time her birthday arrived, she felt confident enough to celebrate by a pool in Las Vegas with her best friends—in a bikini.

Love your curves
Another Hollywood myth? That all actresses want to be a size 0. “Not me!” says Jaime emphatically. “Sure, I wanted to lose my baby weight, but I didn’t want to lose my butt!” To maintain her curvy figure, she does toning workouts and eats a healthy but filling diet. “I think it’s sexy when women have shapely bodies,” says Jaime.

Play up your best features
Since having Dezi, what Jaime finds sexy about herself has changed. “I used to just say my brain,” she explains. “But lately, I love my stomach; after growing a human being inside me, there is nothing more incredible or sexy!” That’s why she focuses heavily on her abs when she’s working out. “Your core supports your spine and your torso,” she says. “Everything you do depends on it.”

Four days a week, Los Angeles trainer Mike Jones leads Jaime through a circuit-training session that might include anything from kickboxing to power-lifting moves. “I get bored easily, so he’s constantly changing the workout,” says Jaime. The routine may vary, but two things always stay the same: “Most of the exercises we do work multiple muscles at once,” says Jones. “And there’s no rest between sets, so Jaime’s heart rate—and calorie burn—stays high.” Check out the March issue for Jaime’s time-saving workout that keeps her red carpet-ready all year long.