1 of 9
Now, here's an unexpected pregnancy craving: Duff "really missed getting my butt kicked" and was pumped to get back to her exercise regimen after welcoming son Luca in March 2012. "I like working out since it makes me feel more clear-headed and positive," she told PARADE a month after giving birth. "There is a little bit of pressure, but most of it comes from me."
2 of 9
MELISSA JOAN HART
Hot mama! Since giving birth in September to her third son, the Melissa & Joey star has dropped two dress sizes, she revealed to PEOPLE in early April. She credits the Nutrisystem diet (she's a paid spokesperson) – and a little help from her family. "My husband [Mark Wilkerson] is really into fitness, and I've always been big into working out," she added. "My boys keep me active as it is."
3 of 9
Sure, Xtina can silence a room with her powerhouse voice alone, but we couldn't stop talking about her x-cellent body after she took the stage at May 19's Billboard Music Awards showing off her continued weight loss. "It's amazing what having some personal time can do, not only for the body but also for the mind and spirit," a source told PEOPLE of the former The Voice coach in March. "She has been trying new types of foods and exploring new methods of exercise. Not for diet or weight, but more for her mind and well-being and overall sense of good health."
4 of 9
5 of 9
Now that's something to sing about! The country crooner flaunted a 20 lbs.-slimmer frame at April's Academy of Country Music Awards. "I've been dieting and exercising," she told PEOPLE of her weight loss. "We all struggle between eating healthy and falling off the wagon." Her splurge? "Occasionally, I have the mac and cheese."
6 of 9
7 of 9
We know it's called The Voice, but who could look away from that body? The newest judge made her debut on the singing competition just two months after welcoming son Milan in January. "I didn't have my four months of maternity like every woman on earth has," she told reporters in April. "It's been a process full of challenges," she added, but clearly her Zumba-fueled workouts helped get her back in shape.
8 of 9
Williams let her 20 lbs.-lighter bod do all the talking when she showed off her svelte figure at an event in May. Just a month before she revealed her inspiration for slimming down to 175 lbs. on her talk show. "I was like, 'Okay, I've got to get ready for my 50th birthday … Fifty, I can see that being one of those milestones that makes you want to jump off of a building."
9 of 9