Glucagon-like peptide-1 (GLP-1) receptor agonists are gaining popularity as a tool to aid in blood sugar regulation and weight loss. However, with the rise in use of GLP-1 medications, trainers working with clients should understand how these medications work so they can create a comprehensive plan that sets the client up for long-term success.
GLP-1s tend to cause a higher rate of lean body mass loss, which means they do not exclusively target fat loss. Research has shown that individuals using GLP-1s may lose more lean mass (muscle) than fat mass (Mehrtash, Dushay, & Manson, 2025). These medications have also been shown to reduce bone density. The combination of bone and muscle loss can be especially detrimental to women over 35, who are already at higher risk for sarcopenia and bone density decline due to hormonal changes associated with perimenopause (Neeland, Linge, & Birkenfeld, 2024). These losses can have a significant impact on both metabolic and physical health. For these reasons, a structured exercise program must be implemented both during and after GLP-1 use.
The Role of a Structured Fitness Plan
Integrating resistance training, mobility work, and cardio is the most effective way to protect muscle and bone while improving metabolic health during GLP-1 therapy (Mehrtash, Dushay, & Manson, 2025).
When starting a client on a program, your role as a trainer is vital. Establishing a clear baseline is the first step. You want to know their current fitness level, resistance training experience, any comorbidities, and physical limitations. In addition to this initial intake, assessments such as a six-minute walk test, bodyweight squat test, or body composition testing (e.g., DEXA or BIA) can provide a more comprehensive picture of their starting point (Neeland, Linge, & Birkenfeld, 2024).
Using both the client interview and physical assessments ensures the safety of the client and helps you build a program that meets the client where they are. This increases buy-in and makes it more likely they will stick with the plan.
Depending on their fitness level, a gradual introduction of movement may be necessary. Clients on GLP-1s often experience fatigue or gastrointestinal side effects, so be prepared to adjust the workout intensity accordingly (Mikdachi & Dunsmoor-Su, 2025). The goal is to build to at least 150 minutes of moderate-intensity aerobic activity each week. This could include brisk walking, walking hills, or structured intervals, as well as cycling. Resistance training should be included two to three times per week using modalities such as resistance bands, dumbbells, or bodyweight exercises. What matters most is choosing resistance that challenges the client appropriately and supports progressive strength training. This approach offers the best chance for muscle and bone preservation, as well as ideal growth.
Mobility work is another key part of the plan. It helps keep joints healthy and maintains balance and coordination, which become even more important for injury prevention as clients age.
Sample Weekly Training Framework for GLP-1 Clients
Every client is different, but here is a sample approach you can adapt based on your client’s current fitness level:
1. Beginners (deconditioned or just starting GLP-1s)
- Cardio: Start with 10–15 minutes of walking, four to five days per week. Gradually build to 30-minute walks.
- Strength: Two sessions per week. Focus on foundational movements, such as bodyweight squats, wall push-ups, and band rows, at low volume and intensity.
- Mobility: Five to ten minutes daily. Prioritize hips, shoulders, and thoracic spine.
2. Intermediate Clients (some experience or previously active)
- Cardio: Aim for 30–40 minutes of exercise, four to five days a week. Mix walking with hills or short intervals, and consider light cycling.
- Strength: Two to three full-body sessions. Incorporate dumbbells and slow-tempo movements to build strength and protect joints.
- Mobility: Include dynamic warm-ups and two dedicated sessions each week.
3. Advanced Clients (regular exercisers with no significant side effects)
- Cardio: Build to 150+ minutes per week with structured aerobic work and moderate-intensity intervals.
- Strength: Three sessions per week using progressive overload. Include free weights, machine training, and circuits.
- Mobility: Maintain joint health through daily warm-ups and cooldowns, and add targeted mobility work on recovery days.
This type of weekly structure provides trainers with a solid foundation for designing individualized programs. The goal isn’t to increase intensity, but to support sustainability and resilience through appropriate progression.
Nutrition and Supplementation
Nutrition should not be overlooked when clients are using GLP-1s. Adequate protein intake is essential, but it can be challenging for some individuals due to reduced appetite or aversions to specific tastes (Mozaffarian et al., 2025). Focus on nutrient-dense protein sources, such as fish, eggs, Greek yogurt, cottage cheese, and nuts or seeds. Protein supplements may be helpful in some cases. Still, protein intake alone is not enough to preserve lean mass without concurrent strength training.
If muscle loss continues despite an optimal exercise and protein intake plan, additional nutrients, such as branched-chain amino acids, creatine, vitamin D, and omega-3 fatty acids, may be beneficial. It is also a smart move to encourage clients to work with a registered dietitian. A dietitian can help them dial in protein intake and determine the proper supplementation based on their individual needs, health history, and goals (Mozaffarian et al., 2025).
Monitoring and Long-Term Support
Regular check-ins and assessments, whether through functional tests, BIA, or DEXA scans, are recommended to evaluate the program’s effectiveness and make necessary adjustments. Continued support is also important once clients discontinue GLP-1s. Staying active, eating well, and maintaining healthy lifestyle habits can help prevent weight regain and maintain improvements in body composition and metabolic health.
Final Thoughts
As fitness professionals, your role is crucial. It is important to meet clients where they are. This means building a plan that complements GLP-1 therapy by combining aerobic and resistance training, promoting adequate protein intake, and incorporating regular monitoring. When executed effectively, this approach can help your clients build strength, improve their well-being, and safeguard their long-term health.
Resources:
1. Mehrtash F, Dushay J, Manson JE. Integrating Diet and Physical Activity When Prescribing GLP-1s—Lifestyle Factors Remain Crucial. JAMA Intern Med. Published online July 14, 2025. doi:10.1001/jamainternmed.2025.1794
2. Mozaffarian, D., Agarwal, M., Aggarwal, M., Alexander, L., Apovian, C. M., Bindlish, S., Bonnet, J., Butsch, W. S., Christensen, S., Gianos, E., Gulati, M., Gupta, A., Horn, D., Kane, R. M., Saluja, J., Sannidhi, D., Stanford, F. C., & Callahan, E. A. (2025). Nutritional priorities to support GLP-1 therapy for obesity: A joint Advisory from the American College of Lifestyle Medicine, the American Society for Nutrition, the Obesity Medicine Association, and The Obesity Society. The American Journal of Clinical Nutrition, 122(1), 344-367. https://doi.org/10.1016/j.ajcnut.2025.04.023
3. Neeland IJ, Linge J, Birkenfeld AL. Changes in lean body mass with glucagon-like peptide-1-based therapies and mitigation strategies. Diabetes Obes Metab. 2024 Sep;26 Suppl 4:16-27. doi: 10.1111/dom.15728. Epub 2024 Jun 27. PMID: 38937282.
4. Chavez AM, Carrasco Barria R, León-Sanz M. Nutrition support whilst on glucagon-like peptide-1 based therapy. Is it necessary? Curr Opin Clin Nutr Metab Care. 2025 Jul 1;28(4):351-357. doi: 10.1097/MCO.0000000000001130. Epub 2025 May 2. PMID: 40401903.
5. Mikdachi H, Dunsmoor-Su R. GLP-1 receptor agonists for weight loss for perimenopausal and postmenopausal women: current evidence. Curr Opin Obstet Gynecol. 2025 Apr 1;37(2):97-101. doi: 10.1097/GCO.0000000000001015. Epub 2025 Feb 25. PMID: 39970049.