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The F45 8-week Challenge That Completely Changed My Outlook On Exercise

fitness woman in gym wear

Rewind to September and I was stuck in a pretty epic exercise rut. After a long, hot summer of picnics, BBQs and more daytime drinking sessions than I can count, I was feeling the post-sunshine slump with no motivation to work out.

So with a New Year looming, I decided to bite the bullet and give the F45 challenge a go.

If you’re on top of your fitness trends, you’ll likely have heard of F45 – it’s the fastest-growing fitness craze in the UK with studios popping up all over the country. There’s currently 30 open across England and Ireland, with another 50 set to open across the UK next year.

The franchise, which originated in fitness mecca Bondi Beach, has amassed a cult following in Australia thanks to its addictive formula. Its USP is 45 minute circuit classes that involve a combination of interval, cardiovascular and strength training, which its trainers claim is the most effective way of burning fat and building lean muscle.

F45 box jumps
The workouts will leave you buzzing with endorphins (F45/PA)

Four times a year, members can take part in a gruellingly tough eight-week ‘challenge’  which involves training as many times as possible, while also following a strict nutrition program.

It made me sweat, it made me almost cry and I pulled a fair few ugly faces along the way too – but it also promised chiselled abs, better energy levels and an insane body fat reduction (just a quick scroll through #F45challenge on Instagram will give you an idea of some of the amazing results).

So how did I fare? Read on to find out…

A bit about me

While I’m naturally not the sportiest of people (I’m the first to admit that I have terrible hand-eye coordination) I’ve always liked being active and was probably at my fittest at the end of 2016, when I trained for a half-marathon.

Since then though, I’ve struggled to get into a regular routine with exercise classes, so I wasn’t particularly surprised my body fat was over the normal amount when I hopped on the Body Scanner at the start of the challenge (a nifty machine that measures your weight, body fat percentage, muscle mass and hydration).

As well as taking my measurements, the F45 team also snapped a few pictures of me so I could compare results eight weeks later.

What shocked me about my initial scan was my visceral fat level, which came in at 15. Amy, who owns London’s F45 Tottenham Court Road studio with her partner Mike, was assigned as my trainer and explained that this is the fat around your organs.

Worryingly, the more of it a person stores, the higher the risk of Type-2 diabetes and heart disease. If I needed any more motivation to take the challenge seriously, it was hearing this.

The workouts

The first thing you should know is the classes are quite intense. Each exercise is ’45’ seconds ‘on’ and ’15’ seconds ‘off’, giving you a super short rest time to gasp some air and gulp some water.

This might sound hellish, but it’s super effective because it pushes your heart into the red zone, where it’s working at between 85-95% of its full capacity for an extended period of time. This means you burn calories for hours after your workout ends.

F45 Challenge
Weighted exercises are all part of the challenge (F45/PA)

The studios mix up a few cardio focused days with others that are all about strength and resistance. Saturday’s hour-long West Hollywood classes with a live DJ are a mixture of the two, and exercises can involve everything from box jumps and burpees to kettlebell swings and battle ropes.

It only took me a few classes to realise the hype around F45. My favourite class is called Panthers, where you do a single lap of 14 different stations, with three sets on each exercise.

Although I found the workouts incredibly challenging – who knew sweat could drip off your face so much during mountain climbers? – I love that you don’t have time to think about how painful the exercises are, as you’re moving stations every minute. Plus, videos of the exercises on screens around the room keep you focused until the buzzer goes.

It’s easy to get hooked, even if you usually hate the gym. As someone who is far from a morning person, I even surprised myself getting up for the 6.15am classes, as I was so motivated by the progress I was making. The day I managed to do my first box jump felt like a huge achievement.

The food

A big part of the challenge is the nutrition plan. The trainers break down everything you should be eating per week, and there’s also an accompanying app with daily meal plans, easy recipes to use, and shopping lists, so you can’t use missing ingredients as an excuse.

I have an admission to make here; I did not follow the meal plans strictly. I could blame that on the fact I am lazy with food prep (having a tiny fridge and three housemates doesn’t help) but I am also an embarrassingly fussy eater, and I had two weekends away during the challenge.

Thai beef salad
My favourite recipe: A tasty Thai beef salad (Georgia Humphreys/PA)

I tried really hard to follow the principles though. The first two weeks (probably the toughest) involved no caffeine, dairy or sugar; I was told this phase is really important for seeing results, as it cleanses the body of toxins to enhance liver function, whilst stimulating metabolism and removing fluid retention.

The middle four weeks is a high protein diet, which helps to define your physique (yay for cheese and peanut butter being back in my life!) while the last two weeks is a fat-stripping phase – so bye, bye carbs.

While there were several moments I really just wanted to eat pizza, I definitely had more energy quite quickly from forming healthier eating habits.

I started meal prepping lunch to take into the office, I stopped drinking squash and fizzy drinks, I completely cut out the needless snacking on sweets and chocolate at my desk and never skipped breakfast (I loved the easy-to-make protein shakes and smoothie recipes).

The results

At my halfway scan, I was told I had lost just over 2 kilos and 5% body fat. But even though my clothes were feeling a little looser, I was stunned how much I had changed when the final transformation photos came through.

I had lost 5.4 kilos and 7% body fat overall. While I was proud of the metrics I’d achieved, I stand by my belief that you should not be defined by your weight. Instead, I want to focus on how much happier I look in my after photos.

Georgia Humphries side view challenge photos
Seeing the results makes the hard work worth it (Georgia Humphries/PA)

I feel stronger (my muscle mass has slightly increased) and more confident than ever (getting a spray tan also helped!) and think it really shows in my smiles and posture. It was also a relief to find out my visceral fat level, which had initially worried me, had gone down.

I'm feeling stronger, happier and healthier
I’m feeling stronger, happier and healthier (Georgia Humphreys/PA)

The verdict

Joining F45 has completely changed the way I see exercise. Now, I feel like it doesn’t have to be a chore and it can be something that I really enjoy. I cannot stress enough what a difference working out five times a week has made to my mental health too.

There’s no denying F45 is pricey, and you could argue it’s possible to do all the exercises involved, or at least similar, in your average gym. But you feel part of a community, it’s exciting knowing no two workouts will be the same, and you’ll find yourself having fun, even when being pushed to your physical limits.

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