GLP-1 Weight Loss Medications: What You Need to Know and Why Strength Training Matters

Oct 11

8 min read

Understanding GLP-1s, their benefits and side effects, and how to protect your muscle while losing weight.

GLP-1 medications have become increasingly popular as a treatment for obesity and weight management. You may have heard of medications such as Mounjaro, Wegovy and Ozempic, but how do they actually work? What are the potential side effects? And, perhaps most importantly, how can you support your body while taking them?

At Embody Training, we believe successful weight management is about more than the number on the scales. Your strength, muscle mass, energy levels, physical health and ability to maintain your results all matter.

Whether you’re considering medication, currently taking it or have already lost weight with its help, understanding the role of exercise and nutrition can make a meaningful difference to your journey.

1. What are GLP-1 medications?

GLP-1 stands for glucagon-like peptide-1, a hormone naturally produced in the gut after eating. It plays an important role in regulating blood glucose, appetite and feelings of fullness.

GLP-1 receptor agonists are medications that mimic the effects of this hormone. They were originally developed to help manage type 2 diabetes, and some are now licensed for weight management.

These medications can help people lose weight by influencing several processes in the body, including:

Reducing appetite: You may feel less hungry throughout the day.
Increasing fullness: You may feel satisfied sooner during meals and stay full for longer.
Reducing food cravings and food noise: Some people find they think about food less frequently or experience fewer urges to eat.
Slowing stomach emptying: Food may leave the stomach more slowly, particularly early in treatment, contributing to feelings of fullness.
Supporting blood glucose control: They help the body release insulin in response to elevated blood glucose and can reduce glucagon secretion when appropriate.

For many people, these effects make it easier to maintain an energy deficit and lose weight.

However, losing weight and losing body fat are not exactly the same thing. Weight loss can include reductions in fat, muscle and other lean tissues, as well as changes in body water. This is why the approach you take alongside medication matters.

2. What types of GLP-1 medications are available?

There are several medications associated with GLP-1 treatment. Although they work in related ways, they are not all identical.

Semaglutide — Ozempic and Wegovy

Semaglutide is a GLP-1 receptor agonist. Ozempic is primarily licensed for type 2 diabetes, while Wegovy is licensed for weight management in eligible patients, subject to prescribing criteria.

Tirzepatide — Mounjaro

Tirzepatide acts on two hormone receptors: GIP and GLP-1. This dual action helps regulate appetite, food intake and blood glucose. In the UK, Mounjaro is used for type 2 diabetes and, for eligible patients, weight management.

Liraglutide — Saxenda and Victoza

Liraglutide is another GLP-1 receptor agonist. Saxenda is used for weight management in eligible patients, whereas Victoza is associated with the treatment of type 2 diabetes.

There are also other medicines within this wider treatment area, and availability and licensing can change.

It is important to understand that these brand names are not interchangeable. They have different approved uses, doses and prescribing requirements. Always follow your prescribing clinician’s instructions and never change your dose or combine these medicines without medical guidance.

3. What are the potential side effects?

GLP-1 and related medications can be effective, but they can also cause side effects. Not everyone experiences them, and their severity varies from person to person.

Common side effects

Digestive symptoms are particularly common, especially when starting treatment or increasing the dose. These may include:

Nausea or feeling sick
Vomiting
Diarrhoea
Constipation
Abdominal discomfort, bloating or indigestion
Reduced appetite
Feeling unusually full after eating a small amount

Some people also experience fatigue, headaches or dizziness. These symptoms may have several causes, including reduced food intake, dehydration or other health factors.

Why nutrition and hydration matter

When your appetite is significantly reduced, it can become difficult to eat enough to meet your body’s needs. You may unintentionally consume too little protein, too few overall calories or insufficient vitamins and minerals.

This is particularly relevant if you are exercising regularly.

To help support your health:

Include a source of protein at meals and snacks where practical.
Choose nutrient-dense foods, including fruit, vegetables and appropriate sources of carbohydrates and healthy fats.
Drink fluids regularly throughout the day.
Avoid forcing large meals if you feel uncomfortable; smaller, manageable meals may be easier to tolerate.
Speak to your healthcare professional if you are struggling to eat or drink enough.

Less common but more serious risks

These medications can also be associated with more serious complications, including gallbladder problems, pancreatitis and dehydration that can contribute to kidney problems. Severe gastrointestinal symptoms may also require medical assessment.

Seek urgent medical advice for severe or persistent abdominal pain, particularly if it spreads to your back, or if you cannot keep fluids down. Severe pain, collapse or other alarming symptoms warrant emergency assessment.

People with diabetes who use insulin or certain other glucose-lowering medicines may have an increased risk of hypoglycaemia and should follow their clinical team’s advice.

These are prescription medicines, so suitability, contraindications, precautions and monitoring should always be discussed with a qualified healthcare professional.

4. Why is resistance training particularly important?

This is one of the most important parts of the weight-loss journey to understand.

When you lose weight, your body does not exclusively use stored body fat. Some lean body mass can also be lost. Lean mass includes muscle and other non-fat tissues, and changes in hydration can affect how it is measured.

This can happen during weight loss through any method, including dietary changes, surgery or medication-assisted weight management.

Resistance training gives your body a reason to maintain its muscle.

When you challenge your muscles through appropriately programmed strength training, you provide a stimulus that supports muscle retention and strength while you lose weight.

Resistance training is not just about building a particular physique. It is also about maintaining physical function, supporting healthy ageing and helping you feel capable and strong.

The benefits of strength training during GLP-1 treatment

1. Helping preserve muscle mass

An energy deficit can contribute to muscle loss, particularly when weight loss is rapid, protein intake is inadequate or activity levels are low. Resistance training helps reduce this risk, although it cannot guarantee that all muscle will be preserved.

2. Maintaining strength and physical function

Muscle helps you lift, carry, climb stairs, get up from the floor and perform everyday tasks. Maintaining strength is valuable whether your goal is improved health, a more athletic appearance or simply feeling stronger in daily life.

3. Supporting body composition

Two people can weigh the same but have different proportions of muscle and fat. By supporting muscle retention, resistance training can help you improve your body composition rather than focusing solely on scale weight.

4. Supporting long-term weight management

Muscle is metabolically active tissue, but it is important not to overstate its effect on metabolism. The main benefits of retaining muscle include strength, physical function and a healthier body composition. Resistance training also helps establish an exercise routine that can continue after weight loss.

5. Building confidence and capability

Progress is not just about losing kilograms. Being able to lift more, improve your technique, complete more repetitions or feel stronger in everyday life are meaningful measures of progress, too.

5. What can happen if you lose weight without resistance training?

If weight loss occurs without a sufficient muscle-preserving stimulus, you may lose more lean mass than you otherwise would.

The extent varies according to the individual, the amount and speed of weight loss, nutritional intake, age, baseline muscle mass and activity levels. Not everyone will experience the same outcome.

Potential consequences include:

Reduced muscle mass: Some of the weight lost may come from muscle rather than body fat.
Declining strength: Everyday tasks and exercise may become more difficult if muscle and strength are not maintained.
Changes in body composition: You may weigh less without achieving the firmer, stronger appearance you hoped for.
Reduced physical capacity: A substantial loss of muscle and strength can affect mobility and physical independence, particularly in vulnerable individuals.
Greater difficulty rebuilding strength later: Muscle can be rebuilt, but this takes time, appropriate training and sufficient nutrition.

It is worth remembering that the number on the scales cannot tell you exactly how much fat or muscle you have lost.

Some research into weight-loss medications has found that lean mass decreases alongside fat mass. This does not mean that everyone taking a GLP-1 medication will experience significant muscle loss, nor does it mean the medication is inherently harmful to muscle. It highlights why preserving lean tissue deserves attention during treatment.

The goal should not simply be to become lighter. It should be to become healthier, stronger and better able to maintain your results.

6. How should you approach resistance training while taking GLP-1 medication?

You do not need to train like an athlete or spend hours in the gym. Consistent, appropriately challenging resistance training is a great starting point.

Prioritise regular strength sessions

For many adults, working towards at least 2/3 resistance-training sessions per week is a sensible starting point, in line with general physical activity guidance. Your ideal programme will depend on your experience, health, recovery and schedule.

A well-designed programme should train the major muscle groups and include movements such as:

Squats or leg presses
Hip hinges, such as Romanian deadlifts
Hip thrusts or other glute-focused exercises
Rows and pulldowns
Chest presses or push-ups
Appropriate core exercises

The programme should be tailored to your ability and progressed gradually as your strength and confidence improve.

Train with purpose, not punishment

You do not need to exhaust yourself in every session. Focus on good technique, suitable loads, consistent attendance and gradual progression.

If you are experiencing nausea, dizziness, unusual fatigue or poor recovery, adjust your session and seek medical advice when needed. Training should support your health, not become another source of stress.

Eat enough protein and overall nutrition

Protein provides the building blocks your body needs to repair and maintain muscle. During weight loss, getting sufficient protein can be particularly important.

However, protein alone cannot replace the benefits of resistance training, and more is not always better. Your needs depend on factors such as body size, activity, age and health status.

Because GLP-1 medications can suppress appetite, it may help to plan protein-containing meals and snacks rather than waiting until you feel very hungry.

A registered dietitian or appropriately qualified healthcare professional can help you determine suitable targets, particularly if you have kidney disease, other medical conditions or difficulty meeting your nutritional needs.

Give recovery the attention it deserves

Muscle adaptation happens through the combination of training, nutrition and recovery. Aim for adequate sleep, hydration and rest between demanding sessions.

If you are consistently exhausted, unable to eat enough or struggling to recover, do not simply push harder. Speak with your prescribing clinician and consider support from a suitably qualified exercise professional.

7. What happens when you stop taking GLP-1 medication?

GLP-1 medications are not a guarantee of permanent weight loss after treatment ends.

Research has shown that some people regain weight after stopping medication, as appetite-regulating effects diminish. The amount regained varies, and long-term outcomes depend on many factors.

This is not a personal failure. Obesity is a complex, chronic condition, and biological responses to weight loss can make maintenance challenging.

It is one reason why building sustainable habits alongside treatment can be valuable.

A consistent approach to strength training, balanced nutrition, daily movement, sleep and ongoing support can help establish foundations for long-term health.

These habits are worthwhile whether you continue medication, change treatment under medical supervision or eventually stop.

Never stop or change a prescribed medication without discussing it with your healthcare professional.

8. The Embody approach: focus on more than the scales

At Embody Training, we believe that weight loss should not come at the expense of your strength, confidence or wellbeing.

If you are taking, or have previously taken, a GLP-1 medication, your training and nutrition deserve an approach that considers the bigger picture.

That means focusing on:

Preserving muscle and developing strength
Supporting adequate protein and overall nutrient intake
Building a realistic, consistent training routine
Monitoring energy, recovery and exercise performance
Developing habits that can support long-term weight management
Celebrating progress beyond body weight alone

You do not need to feel embarrassed about using medication, and you do not need to justify your decision to anyone. Medication can be a valuable part of treatment for eligible people.

Equally, you deserve support that looks beyond a smaller number on the scales.

GLP-1 medication may help with appetite and weight management. Resistance training and appropriate nutrition help you take care of the body you are working towards.

The aim is not simply to lose weight. It is to protect your health, build strength and give yourself the best possible foundation for maintaining your progress.

*This article is for educational purposes only and does not replace individual medical advice. Always consult your prescribing healthcare professional about medication, side effects, nutrition concerns and exercise suitability.