Exercise on GLP-1 Treatment: What to Do on Mounjaro (October 2026)

01 · The short version

What exercise should you do on a GLP-1 medicine?

Aim for a mix of regular moderate activity and resistance work. Nothing special is required: the evidence-backed pattern is regular moderate activity (such as brisk walking) plus resistance work for muscle.¹ You do not need specialist classes, a new gym membership or a punishing routine.

The reason is simple. Mounjaro is licensed for weight management alongside a reduced-calorie diet and increased physical activity.¹ The trial results people quote were achieved with that combination, not with the injection alone. Our guides on Mounjaro weight loss with exercise and how Mounjaro compares with exercise go deeper on how the two fit together.

02 · Your next step

Is this relevant to you, and what comes next?

If you are on Mounjaro or considering it, yes: how you move will shape your results and how well you keep them. If you already exercise, add resistance work and watch your protein. If you are starting from very little, begin with walking and build slowly. Anyone with a heart condition, joint problems or other health concerns should check with their prescriber or GP first.

If you are weighing up treatment itself, our weight loss clinic explains the options, and the Mounjaro pen page shows current prices and how the free consultation works.

03 · Resistance training and muscle

Resistance training: protecting muscle on treatment

Resistance exercise is an important addition to treatment. Some of any rapid weight loss comes from lean tissue, and protecting muscle protects your metabolism, strength and appearance.¹ The two levers are adequate protein and resistance exercise two or more times a week.¹

You do not need a gym. Squats to a chair, lunges, wall or knee press-ups, resistance bands and light free weights all work. Pick a handful of moves covering legs, back, chest and core, and progress by adding repetitions or resistance as they get easier. Technique matters more than load, especially while you are losing weight and your body is changing.

This matters more, not less, as the dose rises and appetite falls.¹ Our guide to exercise on Mounjaro covers practical session ideas in more detail.

04 · Walking and cardio

Is walking enough on GLP-1 treatment?

Walking is a solid foundation, and brisk walking is exactly the kind of regular moderate activity described in the Mounjaro guidance.¹ It is low-risk, free, easy to repeat and kind to a stomach that may be feeling delicate. For many people, walking is the right place to begin.

On its own, walking does not give your muscles the same stimulus that resistance work does. Think of it as the base layer: do it most days, make it brisk enough that you notice your breathing, and add strength work on top. If you enjoy cycling, swimming or classes, those count as well. The best routine is the one you will still be doing months from now.

Start where you are and build; on injection days with early side effects, lighter movement still counts.¹ There is no need to push through nausea or dizziness to hit a target.

05 · Protein, fuel and fluids

Eating and drinking around exercise

Protein and fluids are what make exercise workable on a reduced appetite. Aim to include a protein source at every meal, which is harder when appetite is low.¹ Prioritise protein at each meal, vegetables and fibre, and regular fluids.¹ Treatment is licensed alongside a reduced-calorie diet, so the aim is a sustainable deficit, not a perfect food list.

Smaller, slower meals work better because the stomach empties more slowly. Many people feel worse after very fatty, fried or very sugary food, which is a poor choice before a workout. Try a light, protein-containing snack well before you train instead of a large meal.

Drinking enough matters more on Mounjaro than usual: reduced appetite means less fluid from food, and vomiting or diarrhoea can dehydrate you quickly.¹ Keep water within reach while you exercise. Treat inability to keep fluids down as a contact-your-clinical-team issue, not something to push through.

No supplement is required with Mounjaro, though a standard daily multivitamin is a reasonable safety net while losing weight.¹ Products sold as natural GLP-1 boosters are not equivalents and are not a substitute for prescribed treatment.

06 · Injection days and side effects

Exercising around injection day and side effects

You can keep moving on injection days, but let how you feel set the pace. Early side effects such as nausea are most likely to bother you when you start or step up a dose. On those days, a gentle walk or stretching still counts.¹

Sensible habits help. Train with water to hand, avoid heavy meals beforehand, and stop if you feel unusually weak or unwell. If you faint or have chest pain, a racing heart or difficulty breathing, get medical help straight away. Eating much less can leave you short of energy, so if you regularly feel lightheaded during exercise, discuss it with your prescriber rather than pushing on. New or worrying symptoms can also be reported through the Yellow Card scheme.¹⁹

07 · What if you do not exercise?

What happens if you do not exercise on treatment?

Mounjaro can still reduce appetite without exercise, but that is not how it is licensed or how its results were achieved. In SURMOUNT-1, people taking tirzepatide alongside diet and exercise lost on average 15% of their body weight on 5mg, 19.5% on 10mg and 20.9% on 15mg over 72 weeks, compared with 3.1% with lifestyle changes alone.² These are trial averages, individual results vary, and treatment works alongside a reduced-calorie diet and increased physical activity, not instead of them.²

Without activity you give up the muscle-protecting benefit and a major tool for keeping weight off later. For fuller discussion, see our pages on whether Mounjaro works without exercise, losing weight on Mounjaro without exercise and weight loss injections without exercise.

08 · Keeping results long term

Exercise and keeping weight off

Exercise is a useful habit for keeping weight off. It protects against regain if you later stop treatment.¹ Tirzepatide has a half-life of about five days, so after a final dose it takes roughly four to five weeks to clear the system, and nothing needs doing while it clears.¹ Appetite may return over that period, so habits built during treatment carry real weight.

That is why it makes sense to build your routine while the medicine is helping with appetite, rather than waiting until you stop. Regular movement, protein at meals and resistance work become part of your normal week, not a temporary programme.

09 · Serious side effects

Serious side effects: when to get help straight away

Serious side effects are uncommon but need urgent attention. Seek immediate medical help for: severe, persistent stomach pain that may spread to your back, with or without vomiting (possible pancreatitis); pain in the upper right abdomen, fever or yellowing of skin/eyes (possible gallbladder problems); or signs of a severe allergic reaction such as swelling of the face or throat and difficulty breathing. If you take insulin or a sulfonylurea alongside Mounjaro, watch for low blood sugar (shakiness, sweating, confusion) — your prescriber may need to adjust those medicines.¹