Serena Williams’ fitness routine is an ace.

The 23-time Grand Slam tennis champion nearly poked the internet’s eye out when showing off her post-workout look, which included her rock-hard abs.

In a series of mirror selfies shared to Instagram July 11, Serena displayed her six-pack while sporting an all-black workout ‘fit, complete with a sports bra and leggings. She captioned the post, “Working out and working on my angles.”

After sharing the snaps, the Wimbledon champ was flooded with support from fellow celebs. Comedian Amy Schumerreminded Serena of her legend status by commenting alongside fire emojis, “GOAT.”

Reality TV star La La Anthony chimed in, too, writing, “Always preparing for summer!!!!!”

While the update from Serena—who shares kids Olympia, 7, and Adira River, 22 months, with husband Alexis Ohanian—was celebrated with excitement, it is the result of months of serious effort following the birth of her second daughter in August 2023. 

“Alright, I'm getting back into the swing of things,” the Wyn Beauty founder said in a January 2024 Instagram Reel of her lifting weights. “This is not my usual weight, but it'll do until I get back to where I need to be.”

In addition to her workout updates, the Olympic gold medalist kept her Instagram followers up to date on her weight loss journey by sharing regular check-ins of her trying to fit into a denim Valentino skirt that she bought while pregnant with Adira. In one post, she noted her disappointment in her lack of progress. 

“I’ve been gyming a lot, but I don’t know if the needle is moving,” Serena said while attempting to put on the skirt in a May 2024 Instagram video, but ultimately not fitting. “I can’t say I’m happy about this. It’s getting there. It’s almost there.”

“I just wanna cry,” she continued while emphasizing she wouldn’t give up, “but I’m not. I’m gonna stop eating all those snacks.”

By December, the athlete had achieved her goal and showcased the “finale” of the denim skirt fitting.

“It just fits. An ounce more, it wouldn’t,” Serena said in the Instagram update, before adding “I need to give myself credit.”

Read on for more stars who have showcased their weight loss transformations. 

Tammy Slaton may be a star of TLC’s 1,000-Lb. Sisters, but she didn’t want to be beholden to that title forever.

“I’m down 500 pounds now, around 500,” the 38-year-old said in a confessional on an April 2025 episode of her show. “When I was at my heaviest, I was 700-plus pounds. Right now, I’m weighing in at 238.”

She underwent bariatric surgery in 2022, a choice her physician has praised as the right one for her.

“Tammy has consistently demonstrated her dedication to making sustainable lifestyle changes to maximize the benefits of her surgery,” Dr. Eric Smith told People in October 2024. “I've emphasized the importance of making small, daily adjustments to ensure not only her continued progress but also her long-term success. She's truly committed to her health journey.”

It seems as if every time Jelly Roll hits a red carpet, he’s down a sizable slice of weight.

“I started at 540 pounds and I was 357 pounds this morning,” the singer born Jason DeFord told Pat McAfee in April 2025 during the ESPN host's Big Night Aht live show. “I’m gonna lose another 100 pounds and go skydiving with my wife in Sweden, baby!"

The 6-foot-1 artist admittedly needed to overhaul his relationship with food to get where he wanted to go. "I've always said that I believe obesity is directly connected to mental health," he explained on an October 2024 episode of On Purpose With Jay Shetty. "I know how easy it is for people to go, 'Just quit eatin' so much, just work out, it's so easy!' I wish I looked at food that way.”

Weight was still “the mountain” in front of him, Jelly Roll noted, but his lifestyle changes were working.

"I'm learning, I'm being very diligent with it,” he said. “I'm taking it serious, I'm drinking a bunch of water, I'm cold plunging, I'm eating right, I'm doing good."

Al Roker wasn’t kidding around with the title of his cookbook Recipes to Live By.

Because having lost a hard-fought 100 pounds, the longtime TODAY weatherman literally walks the walk (aiming for at least 10,000 steps a day), watching what he eats and fitting in some sort of exercise on a daily basis.

“My mantra is ‘something is better than nothing,’” he told People in a June 2025 interview. “Maybe you’ll be running marathons or entering weight-lifting contests, but I think most people just want a level of fitness that improves their quality of life.”

Roker underwent gastric bypass surgery in 2002 to get his fitness journey underway, but, he acknowledged, “There’s no magic bullet.”

Surgery is “not the end,” he advised. “You’re still going to have to put in the work.” 

While previously known for the tush push, former Philadelphia Eagles center Jason Kelce has been busy showing off his buff bod.

Not that the athlete wasn’t in fighting shape during his 13-year career in the NFL, but he’s down at least 25 pounds from his playing weight of 295, sharing during the 2025 Truist Championship pro-am golf tournament in Philly that he weighed around 270.

All of which is part of his retirement plan. “I feel like for some reason, 250 to 260 feels like I'll be still big and be happy with the way I look without having a six-pack,” Kelce told GQ in June 2024. “But I’ll still be able to have that stature a little bit.”

Really, the most important aspect for the father of four daughters with wife Kylie Kelce was to be able to keep pace with his kids.

Then weighing in at 277, “my back already feels better,” he shared. “My knees already feel better. So another 20 pounds hopefully will make that much more adept at playing with my children.”

It wasn’t just a change of scenery that did the trick for Rosie O’Donnell, who relocated with her family from the U.S. to Ireland.

"I've lost more weight here,” she shared in a March 2025 TikTok. “I am on Mounjaro for my diabetes and one of the side effects is you lose weight.”

The former View cohost had recently gone shopping for better-fitting clothes in Dublin. “I’m one of those people,” she said, “who's always had a weight issue and now that I'm a size large, instead of an XL or a 2XL, I find it shocking.”

Jazz Jennings embarked on a diet-and-fitness journey in 2022, explaining on Instagram two years later, “I finally care about myself after years of neglecting my health. I had truly let myself go when it came to eating. I am so proud of my weight loss, and I feel my confidence radiates through."

In August 2024, the I Am Jazz star shared that she had lost almost 100 pounds and was “so proud” of her progress.

It turns out Christopher Schwarzenegger is a chip off the ol’ muscly block.

The youngest of Arnold Schwarzenegger and ex-wife Maria Shriver’s four kids together laid low while he dropped 30 pounds, but now he’s back in action.

“It’s not an overnight thing, but it took a lot of trial and error,” he shared in May 2025 at the Inaugural Beacher Vitality Happy & Healthy Summit, noting that just giving up bread made a big difference. “And even still to this day, when [I look at] before and after photos, I don’t feel like I’m an ‘after’ yet.”

Meanwhile, Christopher did not let a certain seven-time Mr. Olympia in on his plan.

“I could never go and say to him, 'You’re overweight,'” dad Arnold told The Times in June 2025. "We just kept introducing healthy foods. We introduced him always to the gym and all of that kind of stuff. And then, out of nowhere, he decided that he wanted to be lean. And now he is. So that is of course fantastic, the self-discipline and the self-motivation. I always felt one day it will have to come from him—and it did.”

Chrissy Metz doesn’t like to run “unless I’m being chased,” she quipped, but she’s a big fan of strength training—and working out is part of the regimen that resulted in her losing 100 pounds.

“I want to age the best way that I can, and I want to be strong,” the This Is Us alum told DailyMail.com in April 2025. “And that’s really the impetus behind any of it.”

To Metz, aging gracefully means “staying strong and flexible,” so she tries to be active every day.

Being a big teddy bear of a guy was part of the package when John Goodman starred on Roseanne in the 1990s, at one point “pushing 400” pounds, as he told David Letterman in 2010. By the time The Conners premiered in 2018, however, family patriarch Dan Conner had made a few lifestyle adjustments.

Goodman quit drinking in 2007, the first step on his road to getting in better shape, while his favorite activities included boxing and walking his dogs.

“I’m breaking a sweat but I’m not going nuts,” he told Peoplein 2010, sharing he had lost about 100 pounds working out six days a week and cutting sugar out of his diet.

Overall, the 6-foot-2 actor has lost about 200 pounds since he was at his peak weight.

“I just got tired, sick and tired of looking at myself,” Goodman told ABC News in 2016. “You’re shaving in the mirror and you don’t want to look at yourself. It gets dangerous.”

Oprah Winfrey has been sharing the highs and lows of her weight loss journey for decades.

From donning skinny jeans and rolling out a wagon loaded with 67 pounds of fat to wow her Oprah Winfrey Show audience in 1988, to buying a stake in WeightWatchers in 2015, she has used her platform to keep the conversation going.

And taking on the topic du jour, she revealed in March 2024 on An Oprah Special: Shame, Blame and the Weight Loss Revolution that, along with eating smaller portions and staying active, she wastaking medication to help regulate her weight.

"It's not just one thing,” she said of her secret to staying fit, “it's multiple things.”

Her goal with the special, Winfrey explained, was to “start releasing the stigma and the shame and the judgment—to stop shaming other people for being overweight or how they choose to lose or not lose weight—and more importantly to stop shaming ourselves."

Lizzo simply wanted to feel better from head to toe.

“Once I started working out for mental health, to have balanced mental health or endorphins, so that I don't look at myself in the mirror and feel ashamed of myself, and feel disgusted with myself,” the “Good as Hell” singer explained in a May 2023 TikTok, “exercise has helped me shift my mind, not my body.”

She acknowledged in a January 2025 TikTok that she was on an “intentional weight loss journey,” her goal was simply to be the best version of herself.

“Even at the end of my weight loss journey, I'm not going to be considered thin by any means,” Lizzo said. “I will still be considered morbidly obese on the BMI and little bros on the internet are still going to call me 'big backed.' But I will be happy."

A second later, the video jumped to Lizzo exclaiming, “And I am happy,” as she showed off a screen showing her body fat had gone down by 16 percent and she’d shaved 10.5 points from her Body Mass Index (BMI).

“Let this be a reminder that you can do anything—anything—you set your mind to,” she added. “Now I guess it’s time to set new goals.”

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