For decades, the fitness industry has sold us the same basic promise: join a gym, follow a training programme, eat better and lose weight.
Weight loss has been one of its biggest selling points. From January membership campaigns to personal training packages, transforming your body has become almost synonymous with getting fit.
But what happens when people can lose substantial amounts of weight without ever setting foot inside a gym?
With medications such as Ozempic, Wegovy and Mounjaro becoming increasingly popular, and newer treatments continuing to emerge, it’s a question I think the fitness industry needs to take seriously.
Are these drugs taking customers away from gyms? Are they making traditional weight-loss programmes less relevant? Or are they exposing something the industry should have addressed years ago?
I have a particular interest in this subject because I’m not just a gym owner and coach. I’ve also used weight-loss medication myself.
And my experience has given me a slightly different perspective.
Why I Decided to Try Retatrutide
Earlier this year, I was preparing to compete at the European No-Gi Brazilian Jiu-Jitsu Championships in Rome.
I’d committed to the lightweight division, which meant weighing no more than 73.5 kg.
The problem was that I was starting at around 81 kg.
I’ve lost weight for competitions before, but usually only three or four kilos. This time I needed to lose approximately eight.
That’s a considerably bigger challenge, especially while trying to maintain the strength, energy and performance needed to compete.
So I decided to try retatrutide.
Retatrutide is an investigational medication that acts on three hormone receptors: GLP-1, GIP and glucagon. Unlike approved treatments such as semaglutide and tirzepatide, it remains unapproved and is still being evaluated in clinical trials.
I was aware that there were uncertainties involved, but I wanted to see whether reducing my appetite would help me reach my competition weight.
And it certainly did.
The Biggest Surprise Wasn’t the Weight Loss
What surprised me most wasn’t how quickly I lost weight, because the weight actually came off quite gradually.
It was how differently I started behaving around food.
I’ve always had a healthy appetite. If there was food left on my plate, I’d finish it. If somebody else left something on theirs, there was a reasonable chance I’d finish that too.
But suddenly, I could eat a meal, feel full and simply stop.
I’d leave food on the plate.
That might sound insignificant, but for me it was a noticeable change.
I wasn’t constantly having to exercise willpower or convince myself not to eat more. I simply didn’t want it.
And that experience made me think about how we talk about weight management.
For years, people have been told that losing weight is simply a matter of eating less and moving more.
Of course, energy balance matters. But appetite, hunger, satiety and eating behaviour are also important.
When medication changes those signals so noticeably, it becomes difficult to argue that weight management is purely a test of discipline.
It Wasn’t All Positive
I experienced nausea, stomach cramps and constipation while using retatrutide.
Most of the time, the symptoms were manageable, but they became considerably worse when I increased the dose.
Interestingly, I don’t recall the medication having a significant negative effect on my training.
I continued preparing for the competition, and although I had plenty of physical problems to deal with, particularly my shoulder and longstanding arthritis, I didn’t notice a meaningful deterioration in my performance that I could attribute to the medication.
Eventually, I made weight and went on to win gold in my division and bronze in the open-weight category.
But I wouldn’t describe the medication as some sort of miracle.
It helped me achieve a particular goal. It also came with side effects and uncertainties.
And I think both sides of that experience deserve to be acknowledged.
Are GLP-1 Drugs Really Hurting Gym Memberships?
As a gym owner, I can understand why some people in the fitness industry might be concerned.
If somebody joins a gym primarily to lose weight, and medication helps them achieve that goal without training, they might question whether they need the membership.
It’s a reasonable concern.
But there’s a difference between something sounding plausible and the evidence actually supporting it.
According to the Health & Fitness Association, gym and fitness facility membership in the United States reached approximately 81 million in 2025, an increase of 5.2% over the previous year.
That’s hardly evidence of an industry being destroyed.
Research published by William Blair in 2026, based on a survey of 300 GLP-1 users, also found that gym membership increased by approximately three percentage points after participants started medication, reaching around 35%.
And 72% of those surveyed reported exercising more frequently after beginning treatment.
PwC’s 2026 research adds another interesting perspective.
Among current GLP-1 users surveyed in the United States, 21% reported increasing their strength training, compared with 17% who had reduced it.
Perhaps most strikingly, 41% said they’d never undertaken strength training at all.
These figures certainly don’t suggest that everyone using weight-loss medication is abandoning exercise.
And there’s a relevant finding closer to home.
PwC’s UK research, published in June 2026, found that 30% of GLP-1 users surveyed reported spending more on fitness.
Of course, these are surveys, and we shouldn’t draw sweeping conclusions from them. They don’t establish whether GLP-1 medications are causing changes in gym membership across the wider population.
But they do suggest that the relationship between medication and exercise is more complicated than people simply abandoning gyms once they start losing weight.
Perhaps the bigger question is what people actually want from a gym once weight loss is no longer their primary motivation.
Weight Loss Isn’t the Same as Fitness
This is where I think the discussion becomes particularly important.
You can lose a considerable amount of body weight without necessarily becoming stronger, fitter or more physically capable.
And while reducing excess body fat can produce meaningful health improvements, weight loss itself doesn’t automatically develop cardiovascular fitness, muscular strength or physical resilience.
I’ve seen people lose significant amounts of weight using these medications and end up looking noticeably gaunt.
Now, appearance alone doesn’t tell us whether somebody is healthy, and I’m certainly not suggesting that people should be judged on how they look.
But it does raise a legitimate concern about body composition.
When we lose weight, we don’t necessarily lose fat alone.
Research examining semaglutide in the STEP 1 trial found substantial reductions in body fat, but also a reduction in lean body mass.
In the body-composition substudy, participants taking semaglutide experienced a 19.3% reduction in total fat mass and a 9.7% reduction in lean body mass over 68 weeks.
Importantly, their overall body composition still improved, with lean mass making up a greater proportion of their total body weight.
That doesn’t mean GLP-1 medications specifically destroy muscle. Lean body mass includes more than skeletal muscle, and some reduction in lean tissue is common during weight loss.
Nevertheless, maintaining muscle strength and physical function is important, particularly as we get older.
That’s why I believe resistance training should be a fundamental part of weight management wherever it’s medically appropriate.
Not necessarily bodybuilding or lifting enormous weights.
Just regular, progressive strength training, supported by adequate nutrition and sufficient protein.
Medication can help with weight loss.
Training can help develop and maintain the physical capabilities that weight loss alone doesn’t necessarily provide.
The Fitness Industry Has Been Selling Weight Loss for Too Long
I’ve spent years coaching martial arts and helping people improve their fitness.
At SBG Manchester, we’ve often told people who wanted to lose weight that training Brazilian Jiu-Jitsu or other martial arts could help them achieve that.
And it can.
But weight loss is only one potential benefit.
Martial arts also develop coordination, balance, cardiovascular fitness, strength, technical skills, confidence and the ability to solve problems under pressure.
There’s also the social side of training, the friendships, the sense of achievement and the satisfaction of learning something difficult.
None of those things can be replaced by an injection.
And I think the wider fitness industry needs to remember that.
If the main thing your gym sells is weight loss, then yes, effective weight-loss medication could challenge your business model.
But if you’re helping people become stronger, healthier, more mobile, more confident and more physically capable, your value goes well beyond what the scales say.
Perhaps GLP-1 medications aren’t destroying fitness.
Perhaps they’re exposing how narrowly we’ve defined it.
My Own Results: Lighter, But Am I Fitter?
Having lost the weight, I can say that I feel better being slimmer.
My clothes fit better, my stomach is flatter and I generally feel good physically.
There are a few things I’m less enthusiastic about, including some loose skin around my chest and stomach.
But overall, I’m pleased with the change.
Have I noticed a dramatic improvement in my fitness or performance?
No, not particularly.
I haven’t suddenly become faster, stronger or more athletic simply because I’m carrying less weight.
People I train with still tell me I’m strong, and I feel that I’ve maintained a good level of strength.
In Brazilian Jiu-Jitsu, extra body weight can actually be an advantage in certain situations.
But being lighter allows me to compete in a weight category that’s more appropriate for my size.
That was my original objective, and I achieved it.
The important thing is that I didn’t stop training while losing weight.
I continued doing the things that help maintain my physical abilities.
And that’s the distinction I keep coming back to.
Are These Drugs a Shortcut?
I don’t particularly like the suggestion that using medication to lose weight is cheating.
If somebody is living with obesity and has struggled for years to lose weight, why should we criticise them for using an effective medical treatment?
If losing that weight improves their health, reduces their risk of disease or makes everyday life easier, that’s a positive outcome.
But I do think there’s a difference between using medication as a tool and expecting it to do everything.
Losing weight may be a major achievement, but it isn’t necessarily the end of the journey.
Strength, fitness, movement, nutrition and long-term health still matter.
And that’s where I believe coaches, personal trainers and gyms have an important role to play.
Not by competing with these medications, but by helping people get the most from the improvements in health and mobility that weight loss can bring.
What About the Long-Term Effects?
I’m open to using GLP-1-based medications in the future, where medically appropriate.
My experience has shown me that appetite-regulating medication can be useful, particularly when combined with a training programme and a clear objective.
But I also think we need to be sensible.
These are powerful medications, not harmless lifestyle supplements.
Some established GLP-1 treatments have substantial clinical evidence behind them, including longer-term safety and effectiveness data.
But questions remain about long-term treatment strategies, individual responses and what happens when people stop taking them.
Newer investigational compounds have even greater uncertainties.
Retatrutide, for example, is still undergoing clinical trials and has not been approved for routine medical use. Products sold outside regulated clinical trials may not contain what they claim and can carry additional safety risks.
So while I can discuss my own experience, I wouldn’t encourage anyone to experiment with unapproved substances or assume that something is safe simply because other people are using it.
Doing your own research is important, but it shouldn’t replace proper medical advice or access to regulated treatments.
The Future of Fitness Should Be About Capability
I don’t think GLP-1 medications are going to destroy the fitness industry.
But I do think they could change it.
And perhaps that’s a good thing.
For too long, we’ve encouraged people to judge their progress almost entirely by the number on the scales or what they see in the mirror.
There’s nothing wrong with wanting to look better. I certainly appreciate being slimmer and having clothes that fit properly.
But appearance shouldn’t be our only measure of success.
Can you move well?
Are you strong enough to manage the physical demands of everyday life?
Do you have the cardiovascular fitness to enjoy the things you want to do?
Can you maintain your independence as you get older?
Are you continuing to challenge yourself and develop new abilities?
Those questions matter far more to me than whether somebody weighs 70, 80 or 100 kilos.
It’s also central to the philosophy behind Beyond Human.
Losing weight can improve your health. Building strength and fitness can expand what you’re capable of doing.
The two aren’t mutually exclusive.
And if GLP-1 medications help people manage their weight while gyms and coaches help them develop strength, fitness and physical capability, perhaps the future of the industry is considerably brighter than some people imagine.
The real opportunity isn’t to fight against weight-loss medication.
It’s to remind people that fitness has always been about far more than losing weight.
Refuse Decline. Become the Exception.
What do you think?
Are GLP-1 medications a threat to the fitness industry, or an opportunity to redefine what fitness actually means?
I’d be interested to hear your thoughts, particularly if you’ve used these medications yourself or work in the fitness industry.
Research and References
- Health & Fitness Association — 2026 US Health & Fitness Consumer Report — US fitness facility membership and participation figures.
- William Blair — GLP-1s and Fitness Clubs: The Structural Case for a Larger Market — Survey findings on gym membership and exercise among GLP-1 users.
- PwC — GLP-1 Consumer Trends 2026 — US research on exercise habits, strength training and changing consumer behaviour.
- PwC UK — What GLP-1 Means for Consumer Markets — UK research on GLP-1 adoption and consumer spending, including fitness.
- STEP 1 Body Composition Substudy — Semaglutide and Lean Mass — Research on changes in fat mass and lean body mass during semaglutide treatment.
- Eli Lilly — What to Know About Retatrutide — Development status, mechanism and safety information for investigational retatrutide.
Disclaimer: This article reflects my personal experience and opinions. It is not medical advice. Weight-management medications should be used under appropriate medical supervision. Retatrutide remains an investigational, unapproved treatment.
