Experts Explain How TikTok’s Viral Leggings Make Your Butt Look Like That

In November 2020, a specific pair of leggings sold by a French company Seasum for $25.99 went viral overnight, thanks to the popular hashtag #TikTokMademeBuyIt, which encourages users to try out items and hacks. The style, featuring a honeycomb-like texture and an indentation on the lower back that simulated a pulled-up thong, was lauded by users for its comfort. But what truly sets these leggings apart from the millions out there was its unique ability to transform anyone’s derriere. One of the first users to share them was Lauren Wolfe, a TikToker with over 500,000, who claimed that her “butt does not look like that” normally. The video now has over 250,000 likes. 

Since then, the hashtag #TikTokLeggings has garnered over 630 million views on the app, 60k reviews on Amazon, and “booty-lifting” dupes from other brands. Even Lizzo is a fan. Picture a pair of leggings that mix the comfort of activewear with the appeal of shapewear, featuring an intentional wedgie that carefully separates your buttcheeks, giving anyone a derriere made for its own reality TV show.

For months now, the success of the TikTok leggings has puzzled shoppers who want to understand how regular butts become superbutts in them. The company claims that the key to its “butt lift” comes from a four-way stretch fabric that “conforms and contours with each pose and movement.” But is that actually what’s going on? 

Textile expert and assistant professor of textile development and marketing at the Fashion Institute of Technology Preeti Arya doesn’t buy it. Arya says that the technique used in these leggings is “west knitting,” the most common type of yarn technology used today, mainly because it allows the garment to stretch even if the fabric doesn’t have elastane. On Seasum’s website, the leggings are described as having a “special mesh textured fabric,” which Arya says may be “just a modification” of regular west knitting that allows for a textured appearance, altering the shape of the legs to look more full. 

Although the company highlights the “textured fabric” as one of the signature factors for the leggings’ “butt-lifting” capabilities, textile expert Preeti Gopinath says there’s no lifting happening at all. Instead, it’s about the design, which draws attention to the wearer’s butt crack. “It’s very rare that you find leggings that have that ruching at the [back] seam,” says Gopinath, who’s the director of the masters of textiles program at Parsons The New School for Design. As opposed to regular leggings, which Arya notes is typically sewn in a way that allows the seam to sit “right on top of the butt line,” these Seasum leggings gather fabric from within the butt-crack to define the two cheeks, giving the illusion of a derriere so big that it’s stretched out the legging’s fabric. The V-shape waistline in the back also exaggerates the scrunching at the seam. Arya calls the Seasum version “a genius design.”

While it seems the whole cyberspace has tried the leggings, not everyone is a fan of them, especially people who wear them to work out. Some user reviews describe the backside seams ripping open, or stretching out to create holes. At the end of the day, clever design can’t compete with an actually powerful butt and its movements. 

The activewear boom is a key factor to understand why these leggings went viral. Before the pandemic, activewear had already been on the rise, with brands like Lululemon, Athleta, and Outdoor Voices leading the market, valued at $155.2 billion in 2018, according to ReportLinker. It’s expected to hit $547 billion by 2024. TikTok is also ripe for items like these to go viral, fostering communities where niche trends and products are becoming the new mainstream. 

Neither Arya or Gopinath believe the leggings are particularly magical. Instead, they point to the triple-threat construction — textured knitting, scrunched back side seam, and dipping waistband —  as giving the appearance of a lifted backside appearance, rather than actually lifting it. Arya says, the real body part these leggings affect isn’t your butt, but rather your brain: “It’s all an optical illusion.”

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Dua Lipa Paired A Neon Suit With This Season’s Hottest Swim Trend

LOS ANGELES, CALIFORNIA – MARCH 14: Dua Lipa attends the 63rd Annual GRAMMY Awards at Los Angeles Convention Center on March 14, 2021 in Los Angeles, California. (Photo by Kevin Mazur/Getty Images for The Recording Academy )

Who says you have to be any wear near a body of water to wear a bikini top? 

On Friday, Dua Lipa shared her latest night-out look on Instagram, including a neon orange suit by David Koma London, paired with a black bikini top, featuring silver gemstone flowers. 

The “Love Again” singer took a cue from one of summer’s biggest swimwear trends: the floss string bikini. As its name suggests, the top features thin ties that wrap around the midriff in a crisscross pattern. Judging by the trends shown during this year’s Miami Swim Week and worn by celebs like Lady Gaga and Kylie Jenner, flossy separates are a post-quarantine must-have. 

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Over the past year, the British-Albanian performer has championed many Y2K trends, including creative variations of the going-out top, donning halter, backless numbers and blinged out camisoles à la 2000s-era Paris Hilton. 

But let’s not forget that summer is almost halfway through, and sharp tailoring is also upon us. As the American workforce returns to IRL offices, the fashion suit is primed to become one of the season’s must-haves. During Paris couture week, street style photographers captured a blazer-heavy vibe, with influencers and celebs pairing structured blazers with tulle skirts, combat boots, and ditching their undershirt for a naked-like look. 

You can recreate the unusual swimwear and workwear combo for your next night out with some of the options below.

At Refinery29, we’re here to help you navigate this overwhelming world of stuff. All of our market picks are independently selected and curated by the editorial team. If you buy something we link to on our site, Refinery29 may earn commission.

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Once reserved for the sceniest of Y2K celebrities — think: Amanda Bynes, Christina Aguilera, Christina Milian, and Nelly Furtado — the belly chain is once again enjoying a resurgence. We’ve seen the waist-skimming baubles in bikini pics posted by Hailey Bieber, Lady Gaga, and Olivia Rodrigo as well as paired with ready-to-wear on Beyoncé, Bella Hadid, and Kim Kardashian. They’ve even appeared on catwalks at Chanel, Jacquemus, and Dior. Essentially, a skimpy summer look is not complete until a gold or silver chain — sometimes embellished with pearls or other stones — is encircling your waist.

Intrigued? Same. But where does one buy a belly chain for an upcoming tropical vacation (or, for that matter, a backyard hang) other than from a DIY shop on Etsy or straight from Chanel? There are some jewelry brands that have been working on supplying us with belly chains. Missoma, Bagatiba, Petit Moments, and more Instagram-favorite brands are all now offering body jewelry for you to test out this summer. 

To help get your collection of belly chains started, we rounded up 16 modern styles ahead.

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Bagatiba Princess Belly Chain, $, available at Bagatiba

Princess Polly Baby Girl Chain Belt, $, available at Princess Polly

Casa Clara Emily Belly Chain, $, available at Revolve

GISENA Dainty Simple Belly Waist Chain, $, available at Etsy

ASOS CURVE Curve Body Chain, $, available at ASOS

bstrdStyle Moonstone Belly Chain, $, available at Etsy

Versace Medusa Chain Belt, $, available at Farfetch

8 Other Reasons Waist Chain, $, available at 8 Other Reasons

Missoma Baroque Pearl Figaro Chain Belt, $, available at Missoma

Urban Outfitters Delicate Pearl Belly Chain, $, available at Urban Outffiters

Wild Fable Butterfly Chain Belt, $, available at Target

Ariana Ost Belly Chain, $, available at Free People

Michael Kors Triple Chain Belt, $, available at Nordstrom

AZ FACTORY Flat Chain Belt, $, available at Farfetch

Ellie Vail Jewelry Viola Paper Clip Waist Chain, $, available at Ellie Vail Jewelry

EverythingForLessUSA Plus-Size Chain Belt, $, available at Etsy

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Allyson Felix Is Wearing Her Own Brand Of Sneakers At The Olympics

When American track star Allyson Felix arrived in Eugene, Oregon this past June for the Summer Olympic Trials, the five-time Olympian and holder of nine Olympic medals wasn’t just vying for another opportunity to compete. She was also determined to use the Tokyo games as an opportunity to upend another standard. 

Ahead of the 2021 Olympic Games, Felix announced the launch of her new women’s lifestyle brand, Saysh, as well as the release of its signature sneaker, the Saysh One. The shoe is meant to be worn for everyday use and to fit women’s soles, which, according to Felix, differ in proportion and width, with women, statistically, having skinnier Achilles heels. Among professional athletes, getting your own shoe deal is a lucrative career-defining milestone, and most star athletes end up collaborating with big companies, such as Nike or Adidas. For Felix to found her own sportswear brand is not only uncommon, it’s nearly unprecedented for athletes of her caliber and fame, a statement for women everywhere who see themselves reflected in her fight for equality — on and off the track. 

“This Olympics for me is a lot bigger than trying to run fast,” she says. “There’s been so much adversity to overcome.”

Back in 2019, Felix shocked the sports world when she accused Nike — her official sponsor at the time — of discrimination. In a New York Times op-ed, Felix narrated how the company offered her 70% less money when she re-negotiated her contract after becoming a mother. “I felt pressure to return to form as soon as possible after the birth of my daughter,” she wrote, explaining how after she underwent an emergency C-section at 32 weeks because of life-threatening pre-eclampsia, she was expected to prove to Nike that she was more committed to the track than her own health. At the time, two former Nike athletes, runners Alysia Montaño and Kara Goucher, shared similar stories in a New York Times investigation. (Nike has since updated its policies so as to not penalize sponsored athletes who “decide to have a baby.”)

Felix went on to sign with Athleta, which she says showed her that “things could be done differently.” Now, she’s on her way to the Olympics sponsored by both Athleta and her own company, donning both brands throughout the event. “I’m so, so proud,” the entrepreneur says. “This is something that I never thought I’d do.”

To launch Saysh — named after the term “seiche” that describes a standing wave which forms in enclosed bodies of water such as lakes — Felix knew she needed more than her athletic experience. Although she’s one of the most decorated athletes of all time, designing sneakers required the help of fabrication and engineering experts. But Felix didn’t want any experts; she wanted women. With the help of sportswear veteran Tiffany Beers, Felix enlisted Natalie Candrian, a Swiss designer with over 20 years of experience working in sportswear, who had left Nike to work independently in 2013. “I got to design and build something for women,” says Candrian. “I don’t think I’ve got to do that before.”

After the first meeting, she had two feelings she wanted to evoke through the shoe: flow and grace. “I thought, ‘What is an equivalent in a fashion piece that gives you the feeling that it’s an easy piece to wear?’,” says Candrian. “To me, it’s the wrap dress from Diane von Furstenberg.” The wrap dress, a fashion staple of the the 1970s, revolutionized the way women dressed, offering a practical but glamorous look that allowed women, who were moving into the workforce en masse, to move freely and to dress chicly without too much fuss. Candrian says that the DVF wrap dress is “something we can all wear, no matter your age, no matter who you are, no matter what you’re up to and where you live.” That’s what the Saysh One was created to do for women. 

Candrian says that women-centric design is not yet a reality inside the sneaker world. Even when sneaker brands like Nike, Rebook, and Adidas market their shoes for women, Candrian says they are almost never designed with a woman’s foot in mind. Instead, they are sized-down versions of men’s shoes. 

But the Saysh One was created around a woman’s foot, designed for both performance and everyday wear. They are also fashionable: a textured toe box with matching laces with a hugging heel, sleek white soles, and the Saysh logo on its back. The toe box is shaped with flowing lines in a darker shade that reminded Candrian of track lines from the first time she designed them on paper. She says it’s an homage to “Allyson’s turf and office.”

Back in June, Felix had a chance to test them on the track at the Olympic Trials, after Candrian and a team of two former Nike engineers helped Saysh build a spiked version of their namesake model. It’s 3.7 ounces, the lightest shoe Felix says she’s ever run in. Now, she could break the record as the most decorated Olympian in history wearing a brilliant decoration of her own design. 

Felix is set to debut her Saysh One spikes at the 2021 Olympic Games on July 30.

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