On TikTok, a five-step diet-and-exercise challenge has gone viral over the past year.
The "75 Hard" challenge incorporates reading, eating, and fitness advice developed by a CEO.
A fitness expert told Insider the challenge is based on "extremes" and may be too strict for some.
On TikTok, a 75-day diet-and-exercise regime is going viral, with creators documenting the challenge as they complete it day by day.
The hashtag #75Hard currently has over 1 billion views on the platform.
The program was developed by Andy Frisella, the CEO of the supplement company 1st Phorm International. It involves spending 75 days sticking to five rules: follow a structured diet (this can be any diet of the person's choosing), do two 45-minute workouts a day, one of which must be outside, drink a gallon of water a day, read 10 pages of "educational nonfiction" a day, and take a daily "progress picture."
The regime has developed a reputation for being particularly intense online, as the rules are far more extensive and detailed than those of other popular short-term exercise challenges such as the 30-day ab challenge or 30-day plank challenge.
Short and intense exercise challenges often go viral on social media, but experts have said that "fad" weight-loss regimes can be ineffective and even dangerous, because they create "unrealistic expectations" for fitness and body transformation.
The "75 Hard" challenge has come under similar scrutiny. While some participants say they've benefited from it, others say the trend promotes "diet culture" and makes people feel like they have to complete the challenge for the sake of the trend.
A trainer told Insider aspects of the challenge are unnecessarily extreme and, while it may yield flashy results for some people, it could cause burnout instead of progress for most.
A TikToker who completed the challenge said posting about it on social media helped hold her accountable
Frisella's program became popular on TikTok in late 2021, with creators who typically post fitness content making daily videos to document their progress. Creators, who show their physical and mental improvements after the challenge, have often gone viral.
A video posted in March by one couple who said they lost 45 pounds combined after finishing "75 Hard" received 35 million views and 4 million likes on the platform.
Sydney Benjamin, a 26-year-old woman from California, told Insider she completed the "75 Hard" challenge in December 2021.
While certain elements of the challenge were particularly difficult for her, such as having to exercise outside each day no matter the weather or finding time to do all the tasks when her schedule was busy, she said she enjoyed the program overall and would recommend it to others.
"It felt very good to complete it, and my body probably felt the best it's ever felt in my entire life. I felt like I could do pretty much anything," she said.
Benjamin, who has 427,000 TikTok followers, added that filming the experience on the platform provided extra motivation. "Had I not documented it on TikTok, I don't think I would have finished it, because there were like 400,000 people that were looking at me trying to complete this, and personally, I feel like I would have disappointed myself and other people had I not completed it," she said.
The challenge has drawn a mixed response on TikTok
Unlike many other viral exercise trends, which promise weight loss as their primary result, Frisella's original blog post about the challenge, dating back to February 2021, said the "75 Hard" challenge was designed to boost "mental toughness" and to encourage people to "take control" of their lives, without mentioning weight.
Still, some of Benjamin's viewers said they disagreed with her completing the challenge.
"I got a lot of negativity, like, 'This is really bad for you,' 'You're promoting diet culture and fad diets,' and I feel like if they knew my intentionality behind it, it would be a different story," said Benjamin, who told Insider she was doing the challenge to lose weight, but was determined not to start from the beginning if she missed a day to avoid falling into an "unhealthy" mindset.
In his blog post, Frisella stipulated that participants had to follow the rules for 75 days straight, and if they were not able to complete all five steps on any given day, they had to start the challenge again from day one.
Benjamin told Insider she thinks the challenge can become "toxic" if people feel they have to keep starting it over and over again.
Some TikTokers have spoken out against the challenge on TikTok with similar criticisms. One March video, from a user who said the challenge was "too intense and perfectionistic," currently has 200,000 views and 16,000 likes on the platform.
Frisella did not immediately respond to Insider's request for comment.
Experts say extreme diet and fitness changes may set you up for failure and prevent real progress
While the "75 Hard" challenge may get eye-catching results, it's more likely to cause frustration and burnout because of its unnecessary strictness, according to Noam Tamir, the founder and CEO of TS Fitness in New York City.
"I think it could be great for some people, but for the majority of us, it's not so great," he said. "They've created this idea based on extremes, and I'm all about being sustainable."
For instance, experienced athletes may benefit from the challenge of doing two 45-minutes workouts a day, but intense workouts could do more harm than good for fitness beginners.
"Ninety minutes of movement is good, but if you're doing two HIIT workouts a day, it's an easy way to create injury or overdo it. And rest days are super important," he said.
Instead, he recommends aiming for a workout schedule you can stick to consistently to build good habits. As little as one workout a day, two days a week is enough to build muscle, a strength coach previously told Insider.
Similarly, the diet and hydration components of the challenge are arbitrary and too strict, according to Tamir. A gallon of water a day may be too much for some people, and not enough for others, he said, and some diets can be unhealthy, overly strict, or imbalanced.
To work toward a healthier diet, try adding an extra serving of veggies to each meal, or swapping out one processed food a day with a more nutrient-dense alternative, a dietitian previously told Insider.
"I'm not a fan of diets, I'm a fan of proper nutrition," Tamir said. "The problem with a lot of fad diets is only a few people will keep up and the rest won't learn anything when it's over."
The requirement to take progress pictures is likely more of a marketing strategy than an accountability tool, he said. While the pictures can be motivating for participants (and their social-media audiences), it can put too much pressure on aesthetics over actual self-improvement.
Finally, the daily pictures and the requirement to start over if you miss a day could backfire and create a sense of guilt and self-punishment that could prevent you from enjoying exercise and healthy habits in the long term.
"What people aren't seeing is how many people fail. I like to measure progress by whatever has the biggest influence on your life, and that might be how strong you feel or how much better your mental state is," Tamir said.
For more stories like this, check out coverage from Insider's Digital Culture team here.