Ke$ha's Booty Workout: How the Singer's Trainer Whips Her Butt Into Shape

If you follow Ke$ha on Instagram, then you know she's been sharing a lot of risqué shots of her bare booty lately.

Clearly a fan of the "If you've got it, flaunt it" motto—the singer has posted three close-ups of her derriere in October alone, and we're only halfway through the month.

Not that we're judging her. Especially since according to her trainer Kit Rich, the pop star has been putting in a lot of hard work to achieve that perfect posterior. Who could blame her wanting to show it off?

So what exactly does her fitness plan include?

"We've been doing a lot of circuit training and incorporating Pilates exercises with weights that heighten and shape the butt," Kit tells E! News exclusively. "Lunges, squats, stairs and isolated glute exercises."

One of Kit's favorite moves has the singer lunging up stairs. Basically "you skip a step and kick the other leg back," explains Kit. Another go-to: "On hands and knees, place a weight in the crease of the knee and then kick the leg up. Each leg gets about a minute of kicking," she says.

A big turning point in the star's routine was Kit joining her on tour so she could be more consistent with her fitness. "I play her own music while we're working out. I tell her it's the best workout music!" she says. "She's seriously the funniest person I've ever met! She's always making jokes and even when she's tired she still shows up. She's amazing."

It also helps that the star's diet has gotten a healthy transformation. "She makes fresh vegetable and fruit juices in her juicer daily," shares Kit. "Plus, she eats lots of protein—she really loves salmon!—and steamed veggies and tons of water."

Workout post?