All the Contestants Who Got Whipped Into Shape on Dancing with the Stars

By the end of season 25, the Property Brothers star lost 34 lbs. With that drop, he said he's discovering something new: “I’m seeing my abs like I’ve never seen them before!” he told PEOPLE. “But I’m eating a lot more now, just because I need to keep that weight on. It’s like back in my high school and college days. I could eat like a horse that would never put on weight.”

Prior to appearing on season 25 of DWTS, the Pretty Little Liars actress gained 70 lbs. over the course of two years due to a hormonal condition, Polycystic Ovary Syndrome. But in her time on the show, during which she was partnered with Gleb Savchenko, she lost 15 lbs. “I’m feeling like me again,” Pieterse said on the show. “It's not an easy road, but being able to focus on getting myself healthy again, and the fact that I’m seeing results, getting better is all I can ask for.”

Paired with Maksim Chmerkovskiy on season 23, Rose saw results within just a couple weeks of rehearsals on the show. "I feel like I'm getting super toned," she said during an episode of her Loveline With Amber Rose podcast in September 2016. "I feel like I've lost probably 10 lbs., maybe 8 lbs. already. It's serious." Rose credited the unseen hard work with the weight loss: "You're with your partner four to five hours a day. Then you get home, you're on the phone with them, like, what you need to work on, what you need to do."

While dancing with partner Louis van Amstel on season 9 in 2009 (and coming in third place!), Osbourne shed 42 lbs., she later told Access Hollywood. "Louis van Amstel and Dancing with the Stars changed my life, as cheesy and cliché as that sounds," she said.

He'd only just finished his first episode of show in season 24, but Mr. T lost 12 lbs. — just during training for the show's premiere with partner Kym Herjavec. "This Dancing is really making Me Sweat off the Lbs.," he tweeted. "I’ve already lost 12! I am Lean, Mean and 219. I am Agile, Mobile and Hostile. Grrr!"

The former General Hospital star competed all the way back on the show's second season, and credited the intense training regimen with helping her lose the weight she gained during her pregnancy. "The waltz works different muscles from the rumba, which works different muscles from the cha-cha, so you're getting a whole-body thing," Carrere told PEOPLE at the time, admitting that it was a tough workout. "But the twisting through the midsection is quite taxing."

When Seymour competed in season 5, she not only lost weight, but she also gained muscle. "I was 128 before I started, which was heavy for me," she said of her time on the show. "That's a good seven or eight pounds heavier than I ever like to be. Now I'm 108. And it's all muscle."

Murgatroyd knows a thing or two about being in good shape, after more than 10 seasons as a pro on DWTS. She took a break from the show while pregnant with son Shia, but returned for season 24 — which she said helped her with the baby weight. "I still feel like I'm carrying a little bit of weight, and it's coming off really slowly," she said. "I feel like my body is getting stronger. It's getting more flexible. I'm faster every day. I think it's going to take another month or so probably to just fully be back into Peta mode." By season 25, in which she was paired with Nick Lachey, she most definitely was.

Osmond had an exciting season 5 on DWTS — will anyone ever forget that fainting episode? And her turn on the dance floor had an added benefit for her, too: She lost 31 lbs., even after starting the season "out of breath" during rehearsals.

Just three months after giving birth to son Adrian, Zee signed up for season 22 of DWTS, and paired up with pro Val Chmerkovskiy. She didn't weigh herself all season, although she felt more toned throughout, she told PEOPLE. At the end, she stepped on the scale — and saw she only lost two pounds! "That was it!" she said. "It made me feel better that all those years when I thought, 'If I just work out more, I'll lose weight,' I was wrong. Apparently I'm just supposed to be 138 lbs., and that’s good."

When Alley competed on season 12 of DWTS in 2011, she made more headlines for her weight loss than for her moves on the dance floor. Alley famously said she lost a whopping 100 lbs. during her time on the show. (She came in second.) She liked it so much, she did it again, competing on the All Stars season, where she placed seventh.

That's So Raven and Cory in the House star Massey shed pounds during his own turn on season 11 of DWTS, just as he'd been expecting to. "It's crazy to think you're going to come into a competition like this and not lose weight with the hours you're going to have to put in," he told PEOPLE.

He was no stranger to being on stage as a member of Boyz II Men, but it was his season 22 DWTS appearance that really got Morris to drop pounds. After just four weeks on the show, he lost 22 lbs. "I feel great. I have a lot of energy," he told PEOPLE when the show was on the air. "I'm able to continue and persevere in rehearsal. Even when I'm tired, I still feel the energy to continue, and I think I can attribute that to losing weight." He even had to have his tour outfits taken in every week for Boyz II Men.

For extra behind-the-scenes secrets, Bruno-isms, wild moments and more, pick up PEOPLE's new special edition, 25 Seasons of Dancing with the Stars, on newsstands and amazon.com now.