GLP-1 Users Need This Workout Guide: An Exercise Physiologist’s Perspective

If you’re taking a GLP-1 — Ozempic, Wegovy, Mounjaro, Zepbound — and you’ve felt smaller but also a little weaker, you’re not imagining it.

The medications work — really well, in fact — but the scale doesn’t tell you what kind of weight you’re losing. In the landmark STEP 1 trial of semaglutide, about 39% of the weight lost was lean body mass, not fat (Wilding et al., 2021). For tirzepatide in SURMOUNT-1, it was around 25% (Jastreboff et al., 2022). Translation: out of every 10 kg you lose, somewhere between 2.5 and 4 kg is muscle, bone, and connective tissue — unless you train to protect it.

That’s where our team at Vital Performance Care comes in. As Kinesiologists, Exercise Physiologists, and Personal Trainers at Vital Performance Care, this is the workout guide we wish every GLP-1 user had on day one.

Ready to keep the muscle you’ve got? Book a session with me and we’ll build a strength program around your meds, energy, and goals. Book an appointment →

Why exercise matters more on a GLP-1

GLP-1 medications suppress appetite. That’s the mechanism: lower hunger, lower calorie intake, weight loss. But muscle is metabolically expensive tissue. When your body senses a sustained energy deficit and you aren’t actively challenging your muscles, it has no reason to keep them around.

A landmark New England Journal of Medicine trial (Lundgren et al., 2021) randomized adults to liraglutide alone, exercise alone, both, or placebo after an initial weight-loss phase. The combination group – exercise plus the GLP-1 – was the only one that maintained weight loss and preserved lean mass and cardiorespiratory fitness. The drug-only group lost more lean tissue and saw fitness decline.

Read that again: the people who exercised alongside their medication kept their muscle. The people who relied on the drug alone did not.

If you’re unsure if keeping muscle is important or not, think of it from the perspective of glucose & bone mass. When you consume and digest glucose, it circulates in your blood until it finds a place it’s needed. That could be your liver, fat cells, or muscle. Muscle is extremely metabolically active tissue, so it can help “eat up” extra glucose and help stabilize blood sugar or even prevent things like diabetes in the long term. Where bone comes in, is that bone is also metabolically active tissue that constantly build up and breaks down when acted upon. Muscles pull on bone and tell it to build up and stay strong. Without the pull from muscles, or the load from impact, we lose that precious bone and become at risk for things like osteoporosis.

How much muscle am I actually losing?

Honest answer: probably more than you’d like.

Across the major trials, 25–40% of total weight lost on a GLP-1 is lean mass (Conte, Hall, & Klein, 2024). The proportion depends on the drug, the dose, the duration, and – crucially – what else you’re doing.

Why does that matter beyond appearance?

•       Less muscle means a lower resting metabolic rate, which makes weight regain easier later.
•       Less muscle means worse glucose handling – a real concern if you started a GLP-1 for diabetes or insulin resistance.
•       Less muscle means you’re more fragile. Falls, fractures, and frailty become more likely in your 60s and 70s.

You can stop this slide. Resistance training plus adequate protein is the most evidence-supported intervention we have.

How often should I strength train?

The American College of Sports Medicine recommends 2–3 resistance training sessions per week on nonconsecutive days, targeting all major muscle groups (ACSM, 2011). For adults losing weight, ACSM’s weight-management position stand specifically calls out resistance training to preserve fat-free mass during energy restriction (Donnelly et al., 2009).

If you’re starting from scratch, two full-body sessions per week is enough to see real changes. Once you’re consistent, three sessions opens up more progress. (I’ll caveat that with saying: if you’re currently doing zero days per week, just adding 1 can have a massive impact, and then progressively adding more sessions over time as you adapt and feel less sore, is the right way to go!)

Eating enough to support training is half the battle. Liam, our nutritionist, has resources built specifically for clients on GLP-1s – hitting protein and energy targets when your appetite is suppressed. See Liam’s availability and book a nutrition consult to discuss with him. He also just started offering complimentary 15 minute nutrition consults to discuss without fully committing yet. 

Cardio or strength — which matters more?

Both have a place, but if you’re on a GLP-1 and can only choose one, choose strength.

Cardio burns calories during the session and improves cardiovascular health, but it doesn’t signal your body to keep muscle. Resistance training does. In Villareal et al.’s (2017) NEJM trial, older adults losing weight who did combined resistance and aerobic training preserved hip bone density and lean mass far better than aerobic alone.

If you’ve got time for both – fantastic. Aim for 2-3 strength sessions plus 150 minutes of moderate cardio per week. If you’re choosing and are limited by time, strength first.

Heavy weights or higher reps?

This is the question I get most, so I’ll give you the practical answer.

For preserving and building muscle in a caloric deficit, 6–12 reps per set at challenging loads (roughly 60–80% of your one-rep max) is the sweet spot (Schoenfeld et al., 2021). You should be working hard enough that the last 1-2 reps are tough – with good form.

Total volume matters too. Aim for at least 10 working sets per major muscle group per week, spread across your sessions (Schoenfeld, Ogborn, & Krieger, 2017). That sounds like a lot, but it’s just 3–4 exercises per muscle group, 3 sets each, twice a week.

You don’t need a fancy program. You need the basics done well: squats, hinges, presses, pulls, carries and core. Add load over time. Our $20 Strength Club can help guide you through targeting those basics, while showing you exercise demonstrations, and allowing you to track and store your progress.

How much protein do I need?

This is where most GLP-1 users fall short, because the medication kills your appetite right when you need to eat more protein to maintain your muscle mass.

The defensible range during weight loss is 1.6–2.4 g of protein per kg of body weight per day (Helms, Aragon, & Fitschen, 2014; Jäger et al., 2017). For a 75 kg (165 lb) person, that’s 120-180 g of protein daily.

In one landmark study, participants on a steep caloric deficit who lifted weights and ate 2.4 g/kg of protein actually gained 1.2 kg of lean mass while losing 4.8 kg of fat (Longland et al., 2016). That’s body recomposition during weight loss – and it’s possible because of the protein and the training together.

Practical tips when your appetite is suppressed:

•       Lead every meal with protein. Eat that part first.
•       Liquid calories (whey shakes, Greek yogurt smoothies) are easier when food feels heavy.
•       Spread protein across 3-4 feedings rather than one big meal per day.

What if I have nausea or low energy?

This is real, especially in the first weeks of a new dose. Training feels harder.

Some things that help:

•       Train fasted-ish, but not empty. A small protein-forward snack (Greek yogurt, a shake) 60-90 minutes pre-workout settles the stomach better than a full meal.
•       Lower the volume, not the intensity. Two hard sets per exercise on rough days beats four mediocre sets – or skipping entirely.
•       Pull cardio back. If you’re nauseated, low-intensity strength can be more tolerable than zone 2 cardio for most people.
•       Hydrate aggressively. GLP-1s slow gastric emptying; you can become dehydrated without noticing.

If you’re consistently too sick to train, that’s a conversation with your prescriber about dose. We work alongside your medical team, not against them.

What about bone density?

A real concern. Significant weight loss – drug-induced or not – pulls bone mineral density down with it. The Zibellini et al. (2015) meta-analysis estimates roughly 1-2% BMD loss per 10% of body weight lost, with the hip most affected.

The mitigation is the same thing that protects muscle: resistance training plus adequate protein, with calcium and vitamin D sufficiency. Loading the skeleton signals it to stay strong. Cardio alone – particularly non-weight-bearing cardio like cycling – does not provide that signal.

When will I see results?

Strength gains in the first 4-6 weeks are mostly neurological – your nervous system getting better at recruiting the muscle you already have. You’ll feel stronger before you look different.

Visible body composition changes typically show up at the 8–12 week mark with consistent training and adequate protein. The scale may not move dramatically, because you’re losing fat while preserving – or even adding – muscle. Take photos. Measure your waist. Track how heavy your weights are. The scale alone will mislead you.

A sample weekly framework

A starting point, not a prescription. Real programming should be tailored to your history, joints, and equipment. Here’s the absolute most basic week of programming we would expect from a client on GLP-1’s. For something slightly more advanced and complete, our $20 Strength Club has 3 lifts/week.

Day 1 — Full Body A (45 min)

•       Goblet squat: 3-4 × 8
•       Dumbbell bench press: 3-4 × 8
•       One-arm dumbbell row: 3 × 10/s
•       Calf raises: 3 × 10-12/s

Day 2 — Easy cardio + mobility (30 min)

•       Walk, bike, or swim at a conversational pace.

Day 3 — Full Body B (45 min)

•       Romanian deadlift: 3-4 × 8
•       Overhead press (or landmine press): 3 × 8
•       Lat pulldown or assisted pull-up: 3 × 10
•       Plank: 3 × 30 sec

Day 4 — Rest or walk

Day 5 — Full Body A or B (optional third session)

Days 6–7 — One longer cardio session, one easy walk.

If 2–3 strength sessions feels unmanageable, start with one and build. Consistency beats perfection.

Conclusion

GLP-1 medications are a powerful tool. But the version of your body you keep depends on what you do alongside the medication, not just the medication itself. Train 2-3 times a week, hit your protein target, and you preserve the muscle, bone, and metabolism that make weight loss durable – and make you feel strong instead of fragile. 

If you’re not sure where to start, that’s the easiest problem to fix.

Try a $20 Strength Club. It’s the 3 day/week strength program that is fully remote from your app. It’s for people already motivated to get to the gym, but with less clarity around what they should be doing while they’re there. Read more on the $20 Strength Club. 

Is nutrition something you want to explore further? Book at complimentary 15-minute nutrition consult with our nutritionist here. 

References

American College of Sports Medicine. (2011). Quantity and quality of exercise for developing and maintaining cardiorespiratory, musculoskeletal, and neuromotor fitness in apparently healthy adults: Guidance for prescribing exercise. Medicine & Science in Sports & Exercise, 43(7), 1334–1359. https://doi.org/10.1249/MSS.0b013e318213fefb

Conte, C., Hall, K. D., & Klein, S. (2024). Is weight loss–induced muscle mass loss clinically relevant? JAMA, 332(1), 9–10. https://doi.org/10.1001/jama.2024.6586

Donnelly, J. E., Blair, S. N., Jakicic, J. M., Manore, M. M., Rankin, J. W., & Smith, B. K. (2009). Appropriate physical activity intervention strategies for weight loss and prevention of weight regain for adults. Medicine & Science in Sports & Exercise, 41(2), 459–471. https://doi.org/10.1249/MSS.0b013e3181949333

Helms, E. R., Aragon, A. A., & Fitschen, P. J. (2014). Evidence-based recommendations for natural bodybuilding contest preparation: Nutrition and supplementation. Journal of the International Society of Sports Nutrition, 11, 20. https://doi.org/10.1186/1550-2783-11-20

Jäger, R., Kerksick, C. M., Campbell, B. I., Cribb, P. J., Wells, S. D., Skwiat, T. M., Purpura, M., Ziegenfuss, T. N., Ferrando, A. A., Arent, S. M., Smith-Ryan, A. E., Stout, J. R., Arciero, P. J., Ormsbee, M. J., Taylor, L. W., Wilborn, C. D., Kalman, D. S., Kreider, R. B., Willoughby, D. S., … Antonio, J. (2017). International Society of Sports Nutrition position stand: Protein and exercise. Journal of the International Society of Sports Nutrition, 14, 20. https://doi.org/10.1186/s12970-017-0177-8

Jastreboff, A. M., Aronne, L. J., Ahmad, N. N., Wharton, S., Connery, L., Alves, B., Kiyosue, A., Zhang, S., Liu, B., Bunck, M. C., & Stefanski, A. (2022). Tirzepatide once weekly for the treatment of obesity. New England Journal of Medicine, 387(3), 205–216. https://doi.org/10.1056/NEJMoa2206038

Longland, T. M., Oikawa, S. Y., Mitchell, C. J., Devries, M. C., & Phillips, S. M. (2016). Higher compared with lower dietary protein during an energy deficit combined with intense exercise promotes greater lean mass gain and fat mass loss: A randomized trial. American Journal of Clinical Nutrition, 103(3), 738–746. https://doi.org/10.3945/ajcn.115.119339

Lundgren, J. R., Janus, C., Jensen, S. B. K., Juhl, C. R., Olsen, L. M., Christensen, R. M., Svane, M. S., Bandholm, T., Bojsen-Møller, K. N., Blond, M. B., Jensen, J.-E. B., Stallknecht, B. M., Holst, J. J., Madsbad, S., & Torekov, S. S. (2021). Healthy weight loss maintenance with exercise, liraglutide, or both combined. New England Journal of Medicine, 384(18), 1719–1730. https://doi.org/10.1056/NEJMoa2028198

Schoenfeld, B. J., Grgic, J., Van Every, D. W., & Plotkin, D. L. (2021). Loading recommendations for muscle strength, hypertrophy, and local endurance: A re-examination of the repetition continuum. Sports, 9(2), 32. https://doi.org/10.3390/sports9020032

Schoenfeld, B. J., Ogborn, D., & Krieger, J. W. (2017). Dose-response relationship between weekly resistance training volume and increases in muscle mass: A systematic review and meta-analysis. Journal of Sports Sciences, 35(11), 1073–1082. https://doi.org/10.1080/02640414.2016.1210197

Villareal, D. T., Aguirre, L., Gurney, A. B., Waters, D. L., Sinacore, D. R., Colombo, E., Armamento-Villareal, R., & Qualls, C. (2017). Aerobic or resistance exercise, or both, in dieting obese older adults. New England Journal of Medicine, 376(20), 1943–1955. https://doi.org/10.1056/NEJMoa1616338

Wilding, J. P. H., Batterham, R. L., Calanna, S., Davies, M., Van Gaal, L. F., Lingvay, I., McGowan, B. M., Rosenstock, J., Tran, M. T. D., Wadden, T. A., Wharton, S., Yokote, K., Zeuthen, N., & Kushner, R. F. (2021). Once-weekly semaglutide in adults with overweight or obesity. New England Journal of Medicine, 384(11), 989–1002. https://doi.org/10.1056/NEJMoa2032183

Zibellini, J., Seimon, R. V., Lee, C. M. Y., Gibson, A. A., Hsu, M. S. H., Shapses, S. A., Nguyen, T. V., & Sainsbury, A. (2015). Does diet-induced weight loss lead to bone loss in overweight or obese adults? A systematic review and meta-analysis of clinical trials. Journal of Bone and Mineral Research, 30(12), 2168–2178. https://doi.org/10.1002/jbmr.2564