Is 75 Day Hard good for you? Fitness experts examine the challenge

Woman exercising, taking part in the 75 day hard challenge. (Getty Images)
The 75 Day Hard challenge is taking over TikTok feeds right now. (Getty Images) (Getty)

We know TikTok isn't short of a wellness trend or two - cosy-cardio, #silentwalking and soft hiking to name but a few, but the latest fad on the fitness block is considerably more hardcore.

The 75-Day Hard Challenge is having quite the moment on the video-sharing platform right now having clocked up over 44.7 million views. The method involves following a series of strict rules for 75 days, with participants documenting their experiences and progress online. And if it sounds a lot harder than a lazy girl workout, that's because it is.

In light of the challenge’s continuing popularity, fitness experts at Second Nature, have delved into the logistics of the trend to decipher its potential benefits and risks.

Often referred to as 75 Hard, the challenge aims to promote mental wellbeing and mindfulness with participants obliged to follow a series of strict rules for 75 continuous days.

But unlike a normal fitness programme, which allows the odd cheat, if someone slips up here they are forced to restart the whole thing from day one. While 75 Hard’s severity may deter many, others believe that participating in the challenge daily is the quickest way to form positive habits.

Turns out, however, that despite the buzz on social media this isn't actually a new thing, in fact people have been participating in the 75-Day Hard challenge for years

The challenge revolves around following five rules, which include:

1. Follow a strict diet

The diet itself is up to the participant’s choice, but it must revolve around the goal of physical improvement.

"No ‘cheat meals’ or alcohol are allowed throughout the duration of the challenge," explains Robbie Puddick, a registered nutritionist at Second Nature.

Woman eating a restrictive diet. (Getty Images)
The challenge involves following a restrictive diet for 75 days. (Getty Images) (Getty)

2. Complete two 45-minute workouts a day

The challenge specifies that one of these workouts must be completed outdoors.

3. Drink one gallon of water a day

While the NHS recommends drinking around 1.2 litres of water daily, the challenge instructs that participants must drink almost four litres daily.

4. Take a progress picture every day

In compliance with the challenge’s goal of physical transformation, participants must take a picture of themselves daily throughout the challenge.

"Many participants choose to upload these progress pictures on social media, particularly on TikTok," Puddick continues.

5. Read at least ten pages of a book every day

To boost mental wellbeing, the challenge specifies that participants must read at least ten pages of a book daily.

"While the book is up to the participant’s choosing, the challenge specifies that audiobooks are not included," Puddick explains.

Woman drinking a bottle of water. (Getty Images)
Participants of the challenge are encouraged to drink a gallon of water a day. (Getty Images) (Getty)

The challenge focuses on implementing positive habits into your lifestyle and revolves around physical activity, which is why many participants may see a physical transformation throughout the 75 days.

"75 Hard’s daily challenges could act as an intense ‘reset’ period, forcing individuals to consider their habits and prioritise health," Puddick explains.

"The challenge’s consistency is a great way to keep on track of your fitness journey, as participants may notice that certain areas of the challenge get easier day by day. However, it’s important to note that 75 Hard may come with some risks and setbacks to your fitness journey."

Like many viral challenges, there are some concerning setbacks to the 75-Day Hard Challenge which are essential to know before deciding to take part.

1. Following a strict diet

While healthy eating is an essential component of mental wellness, following a strict diet has many downsides, particularly forming an unhealthy relationship with food.

"This challenge ultimately promotes calorie counting, which may lead to undesirable outcomes," says Puddick.

"Developing an unhealthy relationship with food is particularly concerning for younger and more impressionable participants of the challenge who may have come across the physical transformations of 75 Hard on TikTok."

2. Completing two 45-minute workouts

Moving your body is an excellent way to improve our health, but the 75-Day Hard challenge has the potential to put too much pressure on working out.

"Exercise and daily movement are crucial parts of a healthy lifestyle, but two 45-minute workouts in a day may be excessive," Puddick explains.

This part of the challenge fails to consider any other commitments - work, childcare, leisure time.

"Completing shorter bursts of exercise can be a positive alternative to completing 90 minutes of strenuous exercise daily," Puddick advises.

"The 75-Hard Challenge can cause participants to feel guilty if they do not meet this goal, which ultimately creates a negative mindset around working out."

3. Drinking one gallon of water

While the NHS recommends drinking around 1.2 litres of water a day, the challenge instructs that participants must drink almost four litres of water daily.

"While drinking water is hugely important for your physical health, there can occasionally be side effects from drinking a large amount of water in a short time span," Puddick says.

"In some rare cases, drinking too much water can lower the body’s electrolyte levels, which can lead to symptoms such as fatigue and nausea."

Like the strict diet and 90 minutes of daily exercise, it’s important not to take the challenge’s specifications at face value.

Woman who has achieved her fitness goals. (Getty Images)
Experts recommend setting smaller fitness goals. (Getty Images) (Getty)

Like the majority of viral fitness trends, the 75-Day Hard Challenge certainly has some negatives – because of this, it’s hugely important to do your research before deciding whether to participate in viral fitness challenges.

"As previously suggested, 75 Hard may not be suitable younger individuals, such as teenagers who have seen the trend on TikTok, mainly due to the challenge’s harsh rules around dieting and working out," Puddick advises.

"Ultimately the 75-Day Hard Challenge has the potential to place participants under too much pressure, causing them to drop out and lose track of their fitness journey entirely."

While participating in viral challenges can be a great way to motivate yourself, Puddick says short-term fitness trends rarely work out in the long run. Instead he recommends focussing on developing habits sustainability.

"If you still wish to challenge yourself, it can often be more effective to take a more measured approach to exercise," Puddick adds. "For example, if you’re currently walking 5,000 steps a day, you could challenge yourself to walk 6,000 steps a day.

Setting more manageable targets is a much more realistic approach to fitness.

"You may often find yourself beating these targets, which will boost your motivation even further – this is a much more positive alternative to feeling weighed down by unrealistic goals."

Ultimately, it’s about discovering what works best for you and building healthy habits sustainably over the long term.

"This will retrain your mind, so these behaviours become automatic," Puddick adds. "So, try to ignore the pressures, quick fixes, and high expectations of social media as they can often cause more harm than good."