This article originally appeared on InStyle.com.

Janet Jackson is looking better than ever. Not only did the 51-year-old star recently welcome a baby girl, Eissa, she also is in the best shape of her life.

If you think she's been pounding the treadmill or doing some intense spin classes, think again. The famous singer and her trainer devised an entirely new workout plan, and she's lost 70 lbs. without doing any cardio. While still rigorous—they worked out together four times a week for a minimum of 45 minutes—the intense training skipped exercises that tend to be hard on the body.

"We were doing three or four exercises with weights back to back," Jackson's trainer Paulette Sybliss told E! News. "What that does—you would look at her and think she'd done like an hour of cardio with me—but when you're working with weights and you're working the muscle that way, it elevates the heart rate, but also it's creating that fat burning affect both during the session and also when she left me, and that was key."

RELATED: Janet Jackson Makes Rare Red Carpet Appearance in Skintight Leather Skirt

While their initial goal was to lose weight, they're now focusing maintaining her figure and staying healthy. "We're not looking to lose any weight whatsoever," Sybliss continued. "She looks incredible and she's so fit, but she's also healthy."

Despite her focus on staying in incredible shape, Jackson also makes sure to treat herself occasionally. "If Janet feels that she needs to have a chocolate cake, go ahead and have a chocolate cake. You're not eating it every day. You won't get fat overnight."