Forget talking about books - at Kim Kardashian's inaugural book club meeting last year, all her sister Kourtney could focus on was Kim's tiny waist.
"I can't take your hips seriously right now," Kourtney said to Kim. "Because your waist is so small and your hips are so big."
Kardashian hairdresser and BFF Jen Atkin then asked Kim for her measurements, and Kim had Chrissy Teigen guess (she went with 23 inches).
"24," Kim said, with a smirk.
"24? That's insane," Atkin replied.
"It's never been 24 ever in my life," Kim said, and after Atkin asked, added that her hips are 39 inches.
After giving birth to son Saint West, 2, in Dec. 2015, Kim started on the Atkins Diet and jumpstarted her workout routine to get back to her pre-pregnancy shape, and lose the 70 lbs. she gained with Saint and daughter North, 4. But over the last year, Kim took her workouts and diet to another level with trainer Melissa Alcantara.
"Kim told me, 'I love my body. I love the way it looks and I love my hips,' " Alcantara recently told PEOPLE. "She just wanted more muscle. She wanted bigger hamstrings, which accentuates the entire leg. And she wants those cut arms and abs!"
Kim now works out with Alcantara six days a week at 6 a.m., and they focus on different areas of the body each day.
"Kim has been getting some really nice results, like with her triceps!" Alcantara said. "She can't believe how much has changed over the last few months. And when you're in this deep, it's hard to go back. She just keeps it up."
The trainer added that Kim's body goals have changed.
"She didn't want to be skinny. She wanted to have muscle and feel strong. And she wanted to find something she can do for the rest of her life," Alcantara said. "I totally understood where she was coming from."