With the popularity of weight-loss injections, most personal trainers have come across GLP-1 weight-loss clients. And, if you haven’t already, you probably will in the future. 

Research from The Food Foundation estimates that 7% of the UK population are currently using or have used medicines like Mounjaro and Wegovy, with these numbers set to increase further now that Wegovy is available in oral form as well as injections. 

As a personal trainer, you’ll know the importance of providing tailored fitness plans for each client, but there are some vital considerations when combining training with GLP-1 medications. 

We’ll cover everything you need to know in this guide. 

What are GLP-1 Medications and How Do They Work? 

Glucagon-Like Peptide-1 receptor agonists are medications that were previously developed for treating type 2 diabetes. However, in recent years they’ve become a popular and highly effective obesity treatment. 

The most popular GLP-1 medicines in the UK are semaglutide (Wegovy and Rybelsus), liraglutide (Saxenda), and tirzepatide (Mounjaro). 

Each mimics the GLP-1 hormone, which is released by the gut when someone eats. Because these medicines last longer in the body, they can: 

• Enhance blood sugar control by releasing insulin. 
• Increase satiety by slowing stomach emptying. 
• Reduce your appetite by regulating your brain’s hunger signals. 

Research shows that the average person can lose between 8% and 22.5% of their body weight when using GLP-1 medications, with Mounjaro and Wegovy producing the most weight loss (NIH). 

What Personal Trainers Need to Know When Working with GLP-1 Clients

As a Level 3 Qualified PT, it’s your job to tailor fitness plans to each client’s goals, and that means factoring in the potential problems your clients might face. These include muscle loss, nutritional requirements, and side effects. 

Muscle Loss 

Studies show that people using weight loss injections can also experience lean mass loss, which can decrease metabolism, reduce strength, and increase the risks of future weight gain after stopping treatment (PubMed). 

If a client is taking Mounjaro, Saxenda, or Wegovy, strength training is core to preventing excess lean mass loss. 

Trainers should implement GLP-1 muscle loss exercises, including progressive resistance training and using weights. Regular training can enhance fat loss while preserving muscle mass, which speeds up metabolism. 

Lower Appetite 

The main reason GLP-1s are so effective is due to their ability to decrease the user’s appetite. They consume smaller portions and are less likely to snack between meals. 

However, a lower appetite also means less fuel, which can cause problems for strength training and aerobic endurance. 

Protein is essential for not only building but maintaining muscle mass, but it’s also very filling, and your clients might struggle to get their daily recommended intake. 

A specialist nutrition qualification will set you apart from other trainers as you can design protein-focused meal plans that suit GLP-1 clients, including those with special dietary needs. 

Navigating Side Effects 

The majority of side effects associated with GLP-1 medicines are worse when treatment begins, or with each dosage increase. However, common side effects include dizziness, lethargy, and nausea. 

Trainers should plan for these side effects in advance, focusing on steady movements and not pushing clients when they’re experiencing nausea and dizziness. 

It’s also important to note that these effects can be worse in people who are using sulfonylureas and insulin to treat diabetes. 

Understand Your Limits 

Personal trainers aren’t medical experts, and it’s unwise to advise your clients to start, stop, or change GLP-1 medications. 

Instead, you should focus on understanding each client’s needs by asking about their treatment, including dose increase schedules and which side effects they experience. 

Designing a Mounjaro, Saxenda, or Wegovy exercise plan that adapts to each client’s changing needs ensures that you protect them, while also helping them reach agreed milestones. 

Factor in Progress Tracking 

GLP-1 medicines can cause fast weight loss in clients, so monitoring the scales won’t really tell you whether the training is working. If a client increases their dose, they may also notice muscle loss, which can impact their strength. 

Encouraging your clients to take progress photos and track body measurements can enhance motivation. While progressive strength training is an excellent way to enhance body composition, simply being able to maintain strength is a big win for GLP-1 clients. 

Stopping Medication 

Some people choose to stop taking GLP-1 medicines once they achieve their goal weight, while others might find the side effects and ongoing costs too hard to deal with. Unfortunately, stopping treatment often leads to weight gain. 

Research shows that people gain an average of 9lbs (0.4kg) each month after stopping weight loss injections, with many regaining 60% of their starting weight after a year (University of Oxford). 

As a specialist PT, you can help your clients reduce this gain through targeted nutrition plans and weight training. Fitness can be an effective exit strategy from GLP-1 treatments, but clients need to be motivated to continue training and modify their diet. 

The Bottom Line 

GLP-1 medications have helped millions of people worldwide lose weight and improve their overall health, but they can also cause muscle loss and make it harder for individuals to meet their recommended daily protein intake. 

As a personal trainer, it’s your responsibility to help your clients maintain their fitness and build strength while using GLP-1’s, but you should never give them medical advice. 

By implementing progressive training plans and investing in advanced nutrition courses, you can set yourself apart as a specialist weight loss medication fitness coach and work with a growing group of clients. 

The Fitness Circle is one of the UK’s most respected online training providers, helping passionate individuals build a career on their terms. 

Whether you’re new to the industry and start with our Online Personal Training Diploma or are a qualified PT who wants to incorporate nutrition into sessions, our courses come with flexible payment plans and an expert tutor to guide you through your learning journey. 

Please book a free call today.