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Can F45 Really Change Your Body in 8 Weeks? We Put It to the Test

By

Amy Lawrenson

Updated on 09/09/21 02:25PM

Reviewed by

Traci Copeland

Fitness Trainer

Fact checked by

Anna Harris

woman working out on rings — Stuidio Firma / Stocksy

F45 is the Australian group training class that’s taking over across the world. The 45-minute HIIT classes are a mix of cardio and strength moves that will challenge your body beyond what you think it’s capable of. With short, sharp intervals, there isn’t much room to get bored. It also means you won’t be doing any one exercise long enough to hate it.

I put the classes to the test earlier this year (you can read my review of F45 here), and in as little as six classes, it started to change my body. I dropped fat, built lean muscle and I felt a little bit more confident in a bikini. It was during this time that I heard about the eight-week challenge. Eight weeks of as many F45 classes as you can fit in, along with a meal plan and a motivational Facebook group to help you get through it. After the initial eight-week challenge was done and dusted, I was able to get a look at the before and after images (you can see one here). Although it all sounded a bit daunting, they were impressive enough for me to sign up then and there.

Week One

“Weeks one and two are the hardest,” Michael Chapman, co-founder of F45 Tottenham Court Road, warns me on the first day. During my weigh-in where my body weight and fat measurements are taken, he talks me through it. Known as spring training, it’s the detox phase. The idea is that you cut out all coffee, sugar, processed foods and alcohol (essentially anything good) to alkalize your body and to eliminate sugar cravings. According to F45, this primes your body to burn fat most effectively.

All challengers are given access to a free app with a weekly shopping list and daily meals (including recipes). If you’re a fan of MyFitnessPal and logging the minutiae of your daily movements into an app, you’ll love this: You can input all manner of things, like your start weight, goal weight, hours of sleep, exercise, how many meals from the meal plan you’ve eaten, water and supplement intake. Water is the king of the challenge, with everyone encouraged to drink a glass of hot water and lemon first thing in the morning, along with around three liters of water daily. That’s a lot of water, and because of that I now know the toilet at work really well. They also recommend you take a magnesium and calcium supplement daily to try to aid with rest and recovery.

I’m not going to lie, during week one I slipped up on the coffee drinking and didn’t get around to buying any lemons. But I did start taking a Solgar Calcium Magnesium supplement ($25). I also joined the F45 TCR Family Facebook Group, which ended up being brilliant for my motivation. When it comes to classes, it’s up to you how many you attend, but three or more per week is recommended for best results. Oh and be warned, they’re tough, but it's fun (promise).

Classes attended: 3

You basically use the rope to lower yourself down and then to climb back up. Repeat until the beep sounds the end of that interval.

Super-tasty grilled sea bass (they say barbecued, but I’m in a kitchen in Greater London, not Bondi Beach) with broccoli, green beans, garlic and goat cheese, all cooked in coconut oil with a wedge of lemon to serve.

Week Two

I’m struggling to stick to the meal plans. Mike was concerned about how the meals repeat themselves a lot, and you do essentially batch-cook to save time, but it does mean eating a lot of the same meals in a week. I don’t mind that, especially since the meals that I have tried have been tasty. I have spent months of my life counting calories and macros and batch cooking chicken and veggies. It was a running joke at my previous job, because I had the same chicken stew for lunch the whole time I worked there (nine months).

My issues are twofold: First, my boyfriend and I already get food each week, and he doesn’t want to eat the food on the plan. I don’t really want to buy more things just to end up wasting food. Second, I eat out a lot for work, so trying to eat healthily at dinner parties is tricky. I’ve been using the app more as a guide, so if it says chicken salad for lunch or scrambled eggs for breakfast, then I’m finding the nearest equivalents at POD, Abokado or Pret. Unfortunately, the weight doesn’t seem to be shifting as well as I would like, which is no surprise since diet is key when it comes to dropping pounds. On the plus side, I am feeling less bloated thanks to increasing my H20 intake, and I feel like I have more clarity at work.

Worth noting: No class ever feels the same. Even though there are different types like Panthers or Athletica or Foxtrot, if you asked me when I was in the class what one it was I wouldn’t be able to tell you. Every single session feels different since there are so many potential combinations of exercises, no one Panthers or Athletica or Foxtrot class is the same. The only thing I know is that on Monday, Wednesday and Friday, there is more cardio, on Tuesday and Thursday, there is more strength and on Saturday, they have a live DJ. And that’s what I love; nothing puts me off a class more than familiarity (especially where burpees are involved). What’s also good is that, while some classes can have 24 exercises to work through, there are handy F45 TV screens at the front that replay the move on a loop, so you always know what you’re meant to be doing.

Classes attended: 3

This move (no.14 on the screen) involves standing on two boxes and holding the kettlebell between your legs and lowering the weight down almost to the floor, before driving back up to standing with your glutes. My bum ached for days, which means it worked.

You panfry the chicken in chili, paprika and lime so it has tons of flavor. The “salsa” is courgette (or zucchinis if you’re Australian), sweet corn, tomato, red onion and garlic mixed with olive oil and coriander (only if you like it).

Week Three

Week three, and I’m stepping things up a gear. I didn’t see the shift in weight during spring training that I would have liked. I know why; had I followed the meal plan, I would be in better shape. I’ve decided to go back to my trusted method of counting macros (essentially counting the amount of protein, carbohydrates and fats each day, based on what you need), that way I can eat anything and count it. With the meal plan, it’s tasty and easy to follow, but you have to be all in. I’m still using it as a guide and eating some meals off the plan, but I’m adding that extra layer of counting the macros too. It’s the only thing that has actually worked for me.

Weeks three through six are known as regular season. This is all about forming new and hopefully lifelong habits. Like that water-and-lemon-first thing, and factoring in more sleep. The food plan during this phase is focused on high protein to try to support muscle growth and to aid fat loss. I may not be totally sticking to the food plan but high protein meals are top of mind.

Since I’m stepping things up a gear I’ve doubled my classes going from three sessions per week to five or six. I’m hoping that will make up for some of the work-related events I’ve had to attend. Since ramping up my class time, I’ve noticed muscle tone in places like my upper back (just below my arms), and I’m starting to see that line down my stomach, which hints at muscle being built—you know, the one Emily Ratajkowski has (something I so desperately want to achieve, just once in my life).

What’s great about the challenge is that there is a real sense of community within the Facebook group and during the classes. Mike and his partner Amy set up Wednesday evening nutrition talks, they make the challenge's smoothies (on the days they are on the app meal plan) and are generally there to support everyone. Mentioning the challenge is also a great conversation starter when you’re waiting to go into class or with the staff on reception.

Classes attended: 5

Traditional planks are a challenge, but this move, which has your feet perched on two unstable medicine balls, challenges your core even more. Well, since I’m stepping things up a notch…

Yes, this is supposed to be an omelette, but making omelettes is not a skill I possess (I’m blaming it on the pan), so I’m calling this tasty scramble instead. It’s basically two eggs, some egg white, spinach, mushroom and goat cheese. I love that you can totally eat cheese on the meal plan.

Week Four

The end of week four is weigh-in week, and since I’m still struggling to stick with the meal plan (more on that later), I take advantage of the fact that when there is a shake on the plan, the team at F45 will make it for you. Genius.

I’m still heading to F45 four to five times per week and feeling fitter every day. I’m nervous about my weigh-in, I went to Switzerland with work this past week. Needless to say, despite trying to be healthy, the glasses of Prosecco and the Swiss chocolate have meant the number on the scales is not a happy one. But I have to remember that it’s not all about what you weigh, rather how you look and feel. I took pictures of myself at week 1 and 4 in shorts and a sports bra and the change is actually noticeable. My abs have slightly more definition, and I look less bloated.

Come weigh-in day, I discover that I have lost a little fat and gained a little muscle. It’s not a huge difference, but the numbers are moving in the right direction.

F45 8 week challenge review — Amy Lawrenson

The station during one class this week is crawling, but with a difference. You use alternating hands to push a heavy medicine ball forwards as you crawl, then you crawl backwards and pull the ball with alternating hands as you go. Crawling works your whole body, but the addition of the ball challenges your arms and core.

This tastes way too good to be healthy. It includes one frozen banana, chocolate protein powder, coconut milk, desiccated coconut, three cashews, a dash of cinnamon and ice cubes. Bliss.

Week Five

It’s week five, and unfortunately, I’m so busy with work that I only manage two F45 classes. I head to a barre class for work, and I also squeeze in a weight-lifting session at my local gym to make up for it. We moved out of our office last week, and we’re working from home all this week. I end up working in cafes most of the week, which means I have to eat the healthiest food I can. I head to Heal’s café and have a pea and mint soup one day. Another day, I manage to work in Planet Organic, so at least I know I can grab a healthy bite to eat there. With the weather having taken a turn for the worse and being all over town all week, I end up in bed all weekend with a headache, which means no working out for me—but also no drinking or takeaways, so you know, every cloud.

Before I’m bed-ridden, I am put through my paces in a strength class. This lunge with overhead press is brutal, but because it combines two compound exercises in one, you’re burning more calories. What are compound exercises? These are moves that use more than one joint, so with a lunge, you are using your hips and knees, while the overhead press utilizes your shoulders and upper back. If you want to try this at home, hold the bar across your collarbone with your forearms tight to your upper arms. Lunge, and once you are still and stable in the lunge, drive the bar up over your head. Lower the bar before returning back to standing.

Week Six

After this week there is only a fortnight of the challenge left to go. Throughout the weeks, I’ve tried to work out what my sweet spot is in terms of the number of classes I should go to. I tend to go to classes in the mornings, but I’m a bit of a night owl, so on days when I’m booked in, I tend to only get five to six hours of sleep. So the more classes I do, the less sleep I get. It’s all a balancing act. Rest and recovery are key.

This week, I head to two F45 classes and squeeze in two weight-lifting sessions at the gym. For me, my body responds well to heavy lifting combined with a couple of HIIT sessions. The sweet spot appears to be two or three weight lifting and two HIIT sessions. I’m not a fan of cardio. I’d much rather head to an F45 class or boxing session than jump on a treadmill any day.

With your hands on a box and standing on a Bosu ball, you jump as high as you can while attempting to kick your butt with your feet. See, F45 knows how to make cardio fun.

Another snack idea from the app. This time it’s packing celery with tuna and feta cheese. With my diet, it’s my snacking habit that lets me down (I may or may not have just eaten some shortbread while writing this). So these healthy snack ideas are invaluable.

Week Seven

The next two weeks make up the final phase of the challenge known as the World Series, which is designed for “ultimate fat shredding.” Essentially, the diet plan becomes ketogenic, meaning the diet is a high-fat, high-protein, low-carbohydrate ratio. By decreasing your carb intake and upping the fat, it is meant to ensure your body doesn’t have glucose to draw on for energy during workouts so it targets your fat stores instead. Fat burn is accelerated, muscle recovery is enhanced and appetite is suppressed. But look—despite how popular keto is, it’s not exactly healthy to cut out a whole food group for a long period of time, and that’s why this phase is strictly two weeks.

I’ve been honest about my inability to stick to the diet program, so for this phase, I just followed the simple rules: Fewer carbs, more protein and fat. A typical day went like this—breakfast was a Pret egg pot (two eggs and spinach) with coffee. For lunch, I headed to Leon, and I opted for the naked chicken satay burger (no bun). For dinner, I had chicken breast with salad, low-fat grated cheese (yum) and a little Mayonnaise (full fat, of course, which made it even better). It was kind of like a poor man’s Caesar salad, which is a necessity when you’re eating out for two meals a day. When I noticed I liked the meals enough to eat them time and again, and I was losing weight and not wanting to snack, I stuck with it.

Mountain climbers are tough when you’re just doing them on the ground, but if you lift your feet, your arms and core have to work that bit harder.

Simply combine Greek yogurt with raspberries and almond flakes. Want to make it sweeter? Add a sprinkling of Stevia.

Week Eight

The last week! I’m sad that I won’t be going to F45 as regularly after the challenge finishes. This studio isn’t like any I’ve been to before. I can spend ages chatting with the team after class, they’re always so welcoming and there is a true sense of community. I always see the same faces, people happily chat to each other (maybe because there are lots of friendly Australians in the class and us Londoners tend to ignore people). I even go to high-five people at the end of class now, whereas I would do anything to avoid that at the beginning.

Co-founders Amy and Michael have done such a brilliant job of creating an inviting space and a real sense of community. Newcomers are always made to feel welcome and supported during the class. The first session can seem a little daunting, but if you stick with it, I promise you’ll see results. Talking of results, this week I got back on the scales for the final time. Despite having struggled to stick to the meal plan, I finished the eight weeks having dropped 1kg (4.4 lbs) and 2% body fat, while increasing my muscle mass by 1.1kg (2.4lbs). My visceral fat reduced, and I increased my hydration levels too.

At the end of each challenge, a male and female winner is chosen, and this time it was a married couple. I got chatting to the female winner in the changing (yep, people talk in the changing rooms), and she told me that it helped that her husband was doing the challenge as well, as they shared the cooking and encouraged each other to go to classes. If I was to do the challenge again, I would entice a friend to buddy up with me.

Holding a dumbbell in each hand, you simply punch while alternating arms. In some classes, we combined punching with a duck and side step, which is meant to work your glutes and obliques too.

Combine shredded beef with vegetables, coconut milk and peanut butter. Oh, and plenty of garlic and chili to taste.

Tempted to take it on? Head to the F45 website to find out more about the classes and the eight-week challenge, which costs a varying amount depending on studio but gives you two month’s unlimited training, access to the app, and body scans at weeks one, four and eight.

Opening image: @f45_tottenhamcourtroad

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