FM Coaching · Fitness Research
GLP-1 and Strength Coaching: 245-Adult Study Finds Bigger Fat-Loss Changes
A 2026 quasi-experimental study of 245 GLP-1 users linked virtual strength-focused coaching with larger weight and body-fat percentage reductions, with key caveats.
Weight loss on GLP-1 medication raises a question that the number on the scales cannot answer: what exactly has been lost? A paper published online on 1 September 2026 and appearing in the November issue of Diabetes, Obesity and Metabolism reports on 245 adults who had recently begun GLP-1 treatment. Those taking part in a 12-week virtual lifestyle programme that included personalised, strength-focused physical-activity coaching experienced larger adjusted reductions in body weight and body-fat percentage than a usual-care comparison group.
The results are interesting for coaches and people trying to retain physical capability as weight changes. But they should not be turned into a promise that an online programme 'stopped muscle loss'. This was a quasi-experimental study, not a randomised controlled trial; participants were not allocated at random, and body composition came from home bioelectrical-impedance scales rather than direct measurements of skeletal muscle tissue.
What did the 2026 GLP-1 exercise coaching study find?
Over 12 weeks, the intervention group lost an adjusted mean 6.0% of starting body weight versus 3.3% in the usual-care group. The paper also reports body-fat-percentage reductions of 3.3 percentage points versus 1.6 points and changes in muscle-mass percentage of +0.6 points versus +0.2 points, respectively. The investigators interpreted the pattern as evidence that adding structured physical-activity support may improve the quality of weight loss. The peer-reviewed study abstract provides the original figures.
| 12-week adjusted outcome | Virtual coaching group | Usual care group |
|---|---|---|
| Participants | 151 | 94 |
| Change in starting body weight | −6.0% | −3.3% |
| Change in body-fat percentage | −3.3 percentage points | −1.6 percentage points |
| Change in muscle-mass percentage | +0.6 percentage points | +0.2 percentage points |
Important: the muscle figure is a percentage of body mass, not a measured increase in kilograms of muscle. Muscle percentage can rise as fat mass decreases even when absolute muscle tissue does not increase. The abstract does not establish that participants gained muscle or avoided all lean-mass loss.
Can strength training help preserve muscle during GLP-1 weight loss?
Resistance training is a widely recommended component of efforts to preserve strength and muscle during weight loss, including during GLP-1 treatment. It supplies a stimulus to maintain muscle function when overall energy intake is lower. The new study included personalised strength-focused physical-activity coaching, but it cannot separately identify the effect of lifting compared with other features of its lifestyle programme. Maintaining adequate nutrition and considering clinical care remain important.
FM Coaching has already reported on how lean-mass measurements are discussed in GLP-1 research in its Mounjaro muscle-loss evidence review. This new article focuses on a specific coached intervention rather than repeating drug-trial claims.
Does online fitness coaching improve GLP-1 weight-loss results?
In this particular 245-adult study, the coached programme was associated with better weight and body-fat-percentage outcomes than usual care over 12 weeks. Association is not proof of cause: because participants were not randomised, differences in motivation, other medical care, physical activity or starting characteristics may have influenced the results. The programme was also multi-component, so it is inaccurate to say that a standalone personal trainer caused the entire difference.
Research authors were affiliated with Omada Health Inc., a company offering digital health services; readers should account for that affiliation when interpreting findings. Independent randomised studies using more precise measures of tissue composition would strengthen the evidence.
Who participated in the 2026 GLP-1 muscle preservation study?
The analysis included 245 adults with obesity who had initiated GLP-1 therapy for weight loss within eight weeks before baseline. Researchers compared 151 participants in a 12-week virtual GLP-1 lifestyle companion programme with 94 usual-care controls. The study assessed changes at 12 weeks, which is not enough to establish long-term muscle preservation, sustained activity or what happens after medication stops.
What is the difference between muscle percentage and muscle mass?
Muscle percentage describes the estimated proportion of total body weight attributed to muscle; muscle mass is an absolute estimated amount. Consider an illustrative case: if someone has 30kg of estimated muscle at 100kg body weight, their muscle percentage is 30%. If weight later falls to 90kg and estimated muscle remains 30kg, their muscle percentage becomes about 33.3% without gaining any muscle. If total weight falls faster than muscle mass, the percentage can rise even as the absolute amount decreases.
The study measured home bioelectrical impedance, an indirect technique affected by hydration and other variables. This is not the same as demonstrating a rise in contractile muscle tissue through MRI or direct measurement. Avoid interpreting one body-composition scan or smart-scale number in isolation.
What kind of exercise should someone do on GLP-1 medication?
A manageable combination of resistance training, comfortable aerobic activity and daily movement is a sensible general framework, with exercises adapted to the person's health and abilities. For resistance training, a qualified professional might begin with two or three non-consecutive sessions that cover squat or sit-to-stand, hinge, horizontal push, pull and trunk stability patterns. Loads and progressions should reflect capacity, not a generic internet workout.
GLP-1 treatment can affect appetite and cause gastrointestinal symptoms; people may need personalised support around hydration, food intake and exercise tolerance. The prescribing clinician should manage medication-specific decisions. Exercise should not be framed as a substitute for appropriate obesity care.
How much protein helps during weight loss?
Adequate protein intake is important to maintaining muscle, but the appropriate amount depends on age, total energy intake, kidney health, training and individual clinical circumstances. For many exercising adults, sports-nutrition literature discusses approximately 1.4–2.0g per kilogram per day, while older adults and people with certain conditions may need different guidance. A blanket 'eat 200 grams' instruction is not suitable for everyone.
If a person's appetite has dropped sharply, planning normal protein-containing meals may matter more than adding elaborate supplements. FM Coaching's body recomposition after weight loss guide explores ways to structure resistance training and food without promising impossible zero-loss outcomes.
Does the study prove that people gained muscle while losing weight?
No. The abstract reports increases in muscle-mass percentage and greater losses of body-fat percentage, but absolute skeletal muscle gain was not established. In a changing body, relative percentages can be misleading. The study's design and measurement method mean it is better described as evidence of promising body-composition patterns than proof of muscle gain.
Is GLP-1 weight loss better with exercise or medication alone?
Exercise can bring strength, cardiovascular and functional benefits beyond what a medication-only plan measures. This study suggests structured activity support may be associated with better body-composition outcomes. It does not show that exercise works as a replacement for medication where medication is clinically indicated, nor that every person should stop or change therapy. Individuals should discuss treatment decisions with their licensed prescriber.
What are the limitations of the new 2026 GLP-1 coaching study?
Three issues matter. First, non-random assignment limits causal conclusions. Second, home bioelectrical-impedance scales estimate composition indirectly and can be influenced by fluid shifts. Third, 12 weeks is a short follow-up for claims about long-term muscle health or medication discontinuation. The authors' commercial affiliation is also relevant. None of these observations makes the study useless; it means the measured findings should be reported at their actual strength.
Other FM Coaching coverage, including the weight regain after stopping GLP-1 injections report, looks at different research questions and should not be confused with this intervention.
GLP-1 and strength training: FAQs
How many adults were in the GLP-1 coaching study?
245 participants: 151 receiving the virtual programme and 94 receiving usual care.
How much weight did the coaching group lose?
The adjusted mean reduction was 6.0% of starting weight over 12 weeks, versus 3.3% in the comparison group.
Did the participants gain new muscle?
The report found changes in estimated muscle percentage, not proof of increased absolute muscle tissue.
Was the GLP-1 exercise study randomised?
No. It was quasi-experimental, so its findings establish association rather than causation.
Can resistance exercise support muscle preservation?
It provides a useful muscle-strength stimulus during weight loss, but individual outcomes vary and require suitable nutrition and clinical support.
Should I change my GLP-1 medicine because of this study?
No. Medication decisions belong with a qualified prescriber who knows your circumstances.
Original research and editorial disclosure
Stanton LA et al. Quality Plus Quantity: Evaluation of a Virtual GLP-1 Programme With Physical Activity Support to Promote Healthy Body Composition Change During GLP-1 Weight Loss. Diabetes, Obesity and Metabolism, November 2026; published online 1 September. DOI: 10.1111/dom.71152. The authors were affiliated with Omada Health Inc. FM Coaching is not a sponsor of this study. Reviewed 8 November 2026.
Questions and answers
How many people were included in the new GLP-1 coaching study?
245 adults: 151 in the coached programme and 94 usual-care controls.
Did virtual coaching help GLP-1 users lose more weight?
In the quasi-experimental study, the coached group had larger adjusted mean weight and body-fat reductions; causation isn't established.
How much weight did the coached group lose?
6.0% of starting weight compared with 3.3% for usual care over 12 weeks.
Did participants gain muscle tissue?
The study reports a higher estimated muscle-mass percentage, not proof of an increase in absolute muscle mass.
Was this a randomised clinical trial?
No; participants were studied in a quasi-experimental comparison.
Should GLP-1 users do resistance training?
Individualised strength training may support function and muscle maintenance, but it must be adapted to medical history and clinician guidance.