Every week there seems to be a new fitness challenge trending online. But one that鈥檚 managed to remain popular over the last couple of years is the 75 Hard Challenge. On TikTok alone, the hashtag #75Hard has more than .

It鈥檚 easy to see why this particular challenge has remained so popular, with video after video of people showing off their staggering body transformations 鈥 which they claim are the result of the challenge.

The 75 Hard challenge is not for the faint of heart. In short, it involves doing each of the following daily for 75 days:

  • Two 45-minute workouts
  • Following a diet (whatever diet you choose)
  • Reading ten pages of a non-fiction book
  • Drinking 4.5 litres of water

If any component is failed, the challenge must start again from day one.

The creator of this challenge claims that completing it will allow you to  and lead to career success, greater confidence and better relationships alongside being physically fit. There鈥檚 currently no scientific evidence to support these claims.

Although the requirements of the 75 Hard challenge are pretty outlandish by most people鈥檚 standards, seeing the transformations and online testimonials of how the challenge changed lives may explain why many continue to be curious about it.

Here鈥檚 what to know if you鈥檙e thinking about giving it a try.

Is it safe?

The two main components of the 75 Hard challenge (eating right and exercising regularly) are of course good for your health. Plenty of research shows that proper diet and regular exercise  and can prevent chronic and , including some cancers and cardiovascular disease.

But in order for diet and exercise to be effective, they must be done in a safe way.

When exploring the safety (and injury risk) of exercise, one of the most important considerations is . This is the combination of how much, how hard, and how often you exercise.

If you have a high physical load (such as exercising intensely seven days a week), you are more likely to suffer from ,  or other issues 鈥 such as . Overtraining syndrome typically happens when you train too much and and recover too little between exercise. It can lead to fatigue, which may also increase risk of injury.

Previous injuries, age, and even weight can also . These factors will also determine whether or not you can tolerate a high training load.

For most people, training twice a day for 75 days is likely to be too much for them. To reduce the risk of injury it鈥檚 widely recommended to split training sessions up and schedule in .

Not recovering properly or giving yourself rest days may also affect your fitness 鈥 and may actually  to see the results you might be hoping to see when following the 75 Hard challenge.

 and  also have a large effect on your ability to recover well and fuel exercise. But everyone鈥檚 needs are different, so it鈥檚 important to listen to your body. Many generic diets won鈥檛 work for everyone, so adapt the diet you follow as necessary.

Is it life changing?

From a psychological perspective, we can also recognise the potential positive impact of fitness challenges such as 75 Hard on ,  and .

But a person鈥檚 success in completing a challenge like 75 Hard may be underpinned by the type of motivation they have for doing so. According to the 鈥溾, every person has a different type of motivation for doing something.

These range from more beneficial to less beneficial types. It鈥檚 not simply about how much motivation a person has for an activity, but what the quality of that motivation is like.

Beneficial, or quality, types of motivation describe people who do an activity for an intrinsic (internal) reason. For example, they do it because they enjoy exercise or they want to learn new ways of feeling healthy.

Less beneficial types of motivation are when a person does something because of an extrinsic (external) reason. Examples of external reasons include feelings of guilt or shame (such as coercion from others or feeling bad about the way they look), or to receive external rewards such as money or recognition.

If a person has enough of either type of motivation, it鈥檚 probably the motivation needed to get them through the challenge. But the more important issue is whether or not the person maintains the healthy behaviour after finishing the challenge.

Beginning any diet or exercise programme is difficult. New exercisers often hold  of what they can achieve, which can lead them to have trouble prioritising and scheduling exercise. Maintaining lifestyle changes can also be challenging.

Extrinsic reasons for doing something often . Yet when a person does something for intrinsic reasons, they are more likely to  and can maintain the positive outcomes 鈥 such as  and . This may be even more likely if a person has access to  following a structured exercise program.

For some people, the 75 Hard challenge may kickstart them into improving their fitness and lifestyle. But being able to maintain that level of activity may depend heavily on the reasons why they are doing it. The rigid list of tasks and consecutive daily nature of the programme may also may it difficult (and even dangerous) to complete.

Anyone contemplating the 75 Hard challenge should seek advice from their healthcare provider or a fitness trainer, and perhaps consider adapting the tasks to suit their fitness level or personal goals.

Juliette Stebbings, Senior Lecturer in Sport, Exercise and Health Psychology, and Robert Rowland, Senior Teaching Fellow in Strength and Conditioning, at the School of Sport Health and Exercise Science in the Faculty of Science and Health

This article is republished from  under a Creative Commons Licence. .

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