Getting fitness tips on social media can be harmful — but it doesn’t have to be

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Tripods and cameras are scattered between the weights and benches in a Mississauga gym. It’s common to find fitness influencers at First Health Club — recording videos of themselves pumping iron to post on social media. 

Among them is Chelsey Berestecki, 25, a young mom who only started posting fitness content on TikTok and Instagram a few months ago, after years of consuming such content while she tried to lose weight. 

“When I had my son in 2017, I gained a lot of weight with the pregnancy. I was 260 pounds,” she said. “Over the past four years, I’ve lost over 100 pounds.” 

“I would look at TikTok influencers in the fitness industry and kind of … feel like that’s the kind of life I want to live.” 

It’s a feeling that she says often pushed her to eat healthier and go to the gym, even when she didn’t want to.

Only a few months since she’s started posting, she already has over 8,000 followers — and growing — on TikTok. 

While it’s been positive for her, online fitness content often has negative messages. Posts can be misleading. At worst, they can actively cause harm, whether through encouraging extreme dieting or recommending exercises that are not safe for everyone.

Despite the growing popularity of fitness influencers, their health impacts have not been well researched. Burgeoning studies are now starting to fill in the blanks — and even offering up solutions. 

One man’s meat, another man’s poison

A recent study out of the journal Body Image gives us one preliminary look. After examining 200 videos from popular TikTok fitness hashtags, like #fitness, #gymtok, #fittok, Australian researchers found 60 per cent of videos posted by fitness influencers presented misleading or harmful information. 

Authors say the vast majority of people posting the videos lacked important training on what they were posting about. The majority of videos also perpetuated negative messages, including sexualization, objectification (for both men and women), body shaming and excessive dieting.

“Promoting calorie deficits in general was quite a disturbing thing to see,” said Samantha Pryde, the lead author of the study and a PhD candidate at Flinders University in Adelaide, Australia. She says many videos promoted extreme calorie deficits, below public health recommendations, for weight loss. 

“Ninety-five per cent of the people who were posting the videos didn’t actually have relevant health, fitness or nutrition credentials,” she said.

Social media makes it easier for viewers to feel like they have a personal connection to the influencer. That artificial closeness can make statements like “I did this to lose weight” or “here’s what I ate in a day” sound like persuasive, personalized advice, says Pryde. 

“It’s almost like just another friend telling them rather than a random person on the TV or in a magazine,” said Pryde

Personal trainer Jennifer Mulgrew, working out on the other side of the Mississauga gym, understands how powerful personalized advice can be. She has a tripod set up on the other side of the gym, recording her exercises, too; not to post on social media, but to send to clients as references for proper form. She says she winces when she sees some of the exercises being posted online.

“I can just see a back injury happening or a shoulder injury happening,” she said.  

Many influencers haven’t done their homework, learning about different muscle groups and how they work together, Mulgrew says. “They kind of wanted to blast out a bunch of exercises on TikTok, or become viral and get a big name for themselves.”

But Mulgrew admits she still scrolls through fitness hashtags regularly. She sees some redeeming qualities.

“The one thing I love about the influencer world,” she said, “it’s turning more and more people towards that healthy lifestyle.” 

Body image concerns

The Australian study is the first to look into the credibility of fitness influencers, or the content they post on TikTok . But there’s plenty of research looking into the impact of social media on healthy body image. 

One 2023 study, which examined a sample of over 21,000 young people from Australia, Canada, Chile, Mexico, the United Kingdom and the United States, found more time spent on social media was associated with a higher likelihood of body dissatisfaction. 

“Our study results are not surprising to a lot of people” said Karen Hock, a lead author of the study, and a PhD candidate at the University of Waterloo’s School of Public Health Sciences.

“If you do see posts online about fitspiration,” she said, “and if you’re not muscular, like the images that you see, [that’s] been associated with body dissatisfaction because you’re not meeting the ideal standards that you’re seeing online.”

She wants to know more about the ways that social media platforms select the videos they show to users, especially when the content is being offered without the user looking for it or even clicking on it.

“There needs to be more research on social media algorithms themselves, because the algorithms could be reinforcing body image concerns.”

WATCH | How social media impacts body image for teens: 

The impact of social media on body image for teens

2 years ago

Duration 8:07

From editing their faces on apps to undergoing plastic surgery, social media is fuelling a movement among teens to change the way they look to meet unrealistic beauty standards.

Influencing the influencers 

But it might be possible to encourage influencers to create content that produces less harm.  

There’s data that suggests how that could work. A team at Harvard T.H. Chan School of Public Health conducted an experiment last year: they trained a group of influencers on best practices for promoting evidence-based mental health information, sharing digital tookits, holding virtual training sessions and even inviting some to an in-person summit in Boston. 

They then tracked, for about a month, how the content of the videos changed, comparing the trained influencers against a control group of influencers that had not been given the same training. They found those who took part in the training were much more likely to feature evidence-based content.

“We know that we have the ability to influence the influencers,” said Matt Motta, the lead author of a study based on the results. 

“We’re taking scientific evidence and we’re giving it to folks and saying, we know you don’t mean to misinform,” said Motta, who is also a professor at Boston University’s School of Public Health.

“We found creators to be very willing partners.”

Motta thinks this model can be exported to the realm of diet and exercise. Despite unique challenges, like endorsements from businesses that sell products like diet pills, Motta is optimistic about the potential impact.

“This is a problem that is fixable,” he said.

“It just requires buy-in from all of these partners.”

There are other efforts underway to promote evidence-based health information on social media. For instance, the World Health Organization and TikTok announced last month a yearlong collaboration to promote evidence-based health content, and help creators access training programs. 

For content consumers, experts say moderation and skepticism are key in wading through fitness content. 

“We spend a lot of time getting health, diet and fitness information on social media and that in and of itself is not a problem,” said Pryde, the author of the TikTok content analysis. 

“When you are searching for that information, you should find credible sources.”

Even fitness influencers themselves, like Berestecki, take that approach.

“I kind of take everything with a grain of salt.”