8 week fitness challenges are all over Instagram. But are they just crash diets in disguise?

Fitness challenges are not exactly a *new* thing. 

You’ve probably been hearing about them for years and know a lot of people who swear by them. Maybe you’ve even tried one.

It’s easy to see the appeal. They’re generally very affordable, the time commitment isn’t too long, and - if the online progress pictures are anything to go by - people seem to get amazing results. But are they really the key to getting healthy and fit, or just crash diets in disguise?

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Hold up. What is a health and fitness challenge?

Short-term fitness challenges all have different labels and marketing, but at their core they’re about the same thing; revamping diet and exercise routines over a short period of time (usually around eight weeks).

They’re often sold by fitness influencers, online personal trainers, and some commercial gyms, and are usually based around either a generic exercise program and meal plan, or customised based on individual goals. 

Some people take to challenges to lose body fat, some to build muscle or gain weight, and some simply to improve general health and fitness. Sounds cool, right? 

But is this actually a good way to get healthy?

Melanie McGrice, Accredited Practising Dietitian (APD) and a spokesperson for Dietitians Australia, believes a short challenge can be a good way to kick-start healthier habits.

"We know people are more likely to be motivated for a short period of time, so a six-or eight-week period is often a bite sized chunk that people can prioritise their health for," she says.

"It doesn’t mean they’re going to stop all of those changes [after the challenge], but it’s a lot less intimidating to think about making changes for six-to-eight-weeks than for 12 months or a lifetime.

"The more personalised the dietary advice is, the more beneficial. Not only will it be easier to follow, but it will also be more suitable to personal calorie and macronutrient requirements."

Could challenges be harmful?

Ok, so it makes sense that a structured program could be a good way to develop a new routine. 


But are there any negative aspects? According to personal trainer, registered counsellor, and eating psychology coach Sami Rose, strict plans have the potential to be detrimental both physically and mentally.

"I've seen injuries from over-training and lack of guidance, to eating disorders stemmed from coaches enforcing extremely low calories or cutting out entire food groups, and many clients who have never been educated on how to make their own healthy choices once they finish their program," she says.

"A lot of the time there is zero support in these challenges, so if the client doesn't achieve the promised results, they feel like they've failed, when it's actually the program or the coach who's failed them."

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For Karen, 44, from New South Wales, this experience is all too familiar.  

"I’ve done a couple of types [of challenges]. The first lot were all weight loss and to be able to keep up with the fitness group I was a member of," she says.

"It was mostly cardio based exercises, so weight would fall off, but then I would gain it back. [During one challenge] I lost 9.2 kilos in 28 days, but towards the end I got sick due to inappropriate diet and training too much."

"I loved the 12-week style that I did (with another gym), because there wasn’t that pressure to lose a lot [of weight] quickly. It was explained a lot better to me, so I didn’t go crazy and make myself ill."

So, is a challenge even worth doing?

Despite having mixed experiences, Ellis feels fitness challenges are worth trying out - if it's clear from the outset that the program will provide enough support.

"I would say it’s a great place to start, so long as they have all the information on how it will work, how to reach goals, and [explain] that it’s not the end of the world if you had set your goal too high and didn’t reach it," she says.

"It’s a great way to set habits and introduce healthy eating. But I would also say it’s totally up to the person as challenges can be pretty full on."

I want to do a challenge, but how do I choose one?

If there is one thing we know about health, it’s that what works for some won’t work for others.

So how do you know if a fitness program is right for you, and how can you tell the good from the bad?

Firstly, when it comes to nutrition, McGrice says a personalised program is generally preferable compared with a generic meal plan.

"I think [a meal plan] works for some people but won’t work for everyone. Often, it’s too many dietary changes all at once," she says.


"Everyone is unique, so it is best to speak with an accredited practicing dietician who can personalise portions, macronutrients, eating habits, and all of those other nuances to suit individual needs."

Rose also says programs should always be at least semi-customised and emphasises the importance of a supportive coach.

"Your training history should be considered so your program is suited to your experience level and access to equipment, and good support will help you stay accountable and give you an opportunity to learn," she says.

"I'd say the most important factor is having a coach who also cares about your mental health and how you feel, for overall wellbeing," she says.

"If you enjoy the process, training in a way that feels equally challenging and enjoyable, and eating foods that help you feel your best... [the right program] will help you improve your quality of life, instead of taking away from it and missing out on the best parts of life!"

So basically, it sounds like the best kind of challenge is one that doesn’t feel too challenging at all.

Jessica is a content producer and writer based in Sydney, and has a keen interest in popular culture, environmental issues and lifestyle and content. Outside of work she spends most of her time reading, cooking, and scrolling through dog memes.

Feature Image: Getty and Mamamia

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