We did the 6-week F45 challenge workout - and the results were life-changing

Whether you're a workout fanatic or just like to dabble with the odd exercise class, it's likely you've heard of F45. The Aussie franchise founded in 2013 has since swept all over the world offering undeniable results when it comes to fitness and fat loss, as well as an almost cult-like sense of community.

Each F45 studio runs the exact same 45-minute class every day (hence the 45, while the F stands for functional, FYI). They incorporate functional movements, alternating between HIIT-style cardio classes and resistance strength training classes, or sometimes a hybrid mixture of the two. Think squats, dead lifts, pull ups, rowing, skiing, and all that fun stuff.

Every few months, those who want to go hardcore and really push themselves - or just dive in at the deep end when they sign up - can take on the F45 Challenge. For six weeks, participants are encouraged to attend classes five times a week and stick to a meal plan, all with the help of the coaches. Throughout the challenge, there are InBody scans to measure you're weight, muscle mass and body fat percentage so you can adjust your priorities accordingly (and celebrate your wins!)

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With overwhelmingly impressive reviews and 43 London studios to choose from, two members of team HELLO! (and F45 newbies) took on the challenge earlier this year. These are our honest thoughts...

The start is always the hardest part

Hollie: "From Barry’s to 1Rebel, I’m no stranger to a London gym studio, but taking on the F45 challenge having never been to a class was still daunting. I started the challenge feeling quite unhealthy after an indulgent Christmas and January. I was feeling sleep-deprived and I almost turned around on my way in, but I pushed through and walked out feeling like a totally different person.

"By week six I was happily going to classes every day and three months later it’s still a welcome part of my routine - I really miss it if I haven’t been for a while. Moral of the story? The start is almost always the hardest."

James Clear, author of New York Times bestseller Atomic Habits says: "Take whatever habit you're trying to create and scale it down to something that takes two minutes or less to do. So 'do yoga four days a week' means 'take out my yoga mat.'" In this case, by signing up and getting yourself to the studio, you’re already halfway there."

Varied workouts do keep things more interesting

Katy: "The classes are a hybrid mix of HIIT-style cardio and strength training lasting 45 minutes during the week and an hour on Saturdays. In the past, my gym routine involved 30 minutes on the cross-trainer, 10 minutes on the rower, and a few quick reps with a dumbbell before making a swift exit so my first F45 session was a whirlwind experience.

"The fast-paced nature of doing an exercise for 45 seconds, then 15 seconds before jumping to the next station (27 stations in total - two laps of the room) was a bit of a shock to the system but also such an adrenaline rush. I could see why friends who were members had been able to stay so consistent - and trust me, I too would have been sceptical previously. The fact it was fast-paced made it fun, and the variety of exercises made the time go quickly. I had worked hard but actually enjoyed myself."

Being part of a community helps you stick to your fitness goals

Katy: "I was nervous about starting the challenge - however, my mantra at the start of this year was to feel the fear and do it anyway… and I’m really glad I did. The class environment was friendly with zero judgement. The F45 coaches are not only your cheerleaders, but they also help correct your form, explain each exercise and make you reach your full potential. This support is with you throughout your membership, not just the first few classes.

"You also become familiar with others attending the class, doing each exercise station alongside two or three others means you can congratulate them once they’ve completed a tough circuit, or can all breathe that welcomed sigh of relief once you’ve finished. It's the ideal combination of feeling like you’re on your fitness journey whilst still being supported and motivated by those around you. At my studio, they also had a WhatsApp group that you could join when you were doing the challenge so everyone could share wins, offer advice and support each other."

Your diet will change, but it might not be in the way that you think

Hollie: "As I amped up my exercise routine, I found my eating habits started to change too. I used to drink coffee for breakfast, but pushing my body harder meant waking up hungry. Porridge became my new ritual to get me through each morning class.

"After two weeks, I had my first weigh-in and found out I’d lost 1kg, but my muscle mass had stayed almost exactly the same. My main goal was to build muscle, so my coaches recommended I upped my carb intake. Increasing calories isn’t necessarily what I expected when I was working on my body confidence, but I was eating more than ever, and over the following two weeks I gained 1kg of muscle mass while also decreasing my body fat percentage. Of course your recommendations will depend on your personal goals, but you can rule out a crash diet. Luckily I’m a big fan of brown rice, but there are lots of healthy recipes you can find on the F45 app that actually taste great and will also help you get the macros you need."

Exercise really does boost your confidence

Katy: "I felt much physically healthier by the end of the F45 challenge, although, I knew there were still areas outside of the studio I could improve - especially when it came to my diet. However, for me, the real win was getting into a habit of regular exercise - getting out of bed every morning to do exercise is something I would previously have said I could never do - but there I was, doing it. I was dedicating regular time slots to self-care and in turn, I was feeling happier. It was a huge boost to my self-esteem."

Recovery and cooldowns are as important as your workout

Hollie: "I don’t tend to ever skip a cool down as after a HIIT workout the first thing I want to do is lie on the floor, but I didn’t truly realise their importance until I had to rush off at the end of class one morning. Cue severe shoulder pain several hours later and an inability to lift anything for a couple of days. Luckily, one of my coaches is also an Osteopath so I knew I was in safe hands. F45 even has recovery classes to make sure your body is working to the best of its ability. It’s definitely something to keep in mind if you want to get the best results out of the challenge."