GLP-1 Personal Trainer: What the 2026 Research Says Your Clients Need

A plain-English read of the latest research on GLP-1 medication, muscle and movement, and what it means for how you coach.

Your next client segment is already on a GLP-1

11% of US adults now take a GLP-1 medication for weight loss, up from 3% in 2024, according to Gallup’s May to June 2026 survey of 5,065 adults.

Gallup also found that 15% of adults have used one at some point, up from 6% two years ago. That growth means a GLP-1 personal trainer is no longer a niche idea, because the people on these medications are already in your gym, your DMs and your client list.

KFF counts a little differently because it asks about any reason, including diabetes. Its November 2025 poll of 1,350 adults found 12% currently use a GLP-1 and 18% have ever used one, and the numbers below come from the same poll.

GLP-1 clients move less after they start

Daily steps fell from 5,047 to 4,487 after adults with obesity started a GLP-1, a drop of 560 steps a day across 753 people with Fitbit data.

Research on GLP-1 and exercise starts from a simple assumption, that people feel lighter once the weight comes off and move more. Dr. Sajana Maharjan of HSHS St. John’s Hospital presented data at ENDO 2026, the Endocrine Society’s annual meeting, that points the other way, and the time people spent in moderate-to-vigorous activity also fell from 28 to 22 minutes a day.

The drop was not even across the group. HealthDay’s coverage of the study shows men and people with muscle or joint pain moved far less than everyone else.

Muscle loss is real, and the size of it is debated

Some lean mass loss comes with any weight loss, and the open question is whether GLP-1 muscle loss runs higher than dieting alone causes.

A ukactive report led by Gillian L. Hatfield, PhD, of the University of the Fraser Valley puts lean body mass at 20% to 50% of the weight lost. It says that can be similar to the loss seen after bariatric surgery, cancer treatment or 10 years of ageing.

Not everyone agrees on how worried to be. A 2026 paper in Cell Reports Medicine (Langer et al.) reports that weight loss with GLP-1 medicines does not cause a disproportionate loss of muscle mass or function in obese mice and humans, although the human data came from a small proof-of-concept trial.

Part of the disagreement comes down to what gets measured. Lean mass also counts organs and body water, and a 2026 review in the International Journal of Molecular Sciences puts it plainly: “Lean mass, however, is not synonymous with skeletal muscle.”

GLP-1 strength training: what the research backs

Resistance training with enough protein is the approach most sources recommend, although direct trial evidence in GLP-1 users is still being built.

The ukactive report cites chief medical officer guidelines of two to three strength sessions a week, plus 150 minutes of moderate to vigorous activity.

What happened when 200 adults had expert support

A cohort presented at the European Congress on Obesity 2025 followed 200 adults on semaglutide (40%) or tirzepatide (60%) for six months. Each was supervised by an obesity physician who taught them about resistance training and protein, and Patient Care reported that they lost mostly fat.

Older evidence comes from dieting studies. Gross and Brinkmann cite a meta-analysis (Sardeli et al.) showing that supervised resistance training at a minimum of 65% of one-rep max for 12 to 24 weeks can reduce more than 90% of lean body mass loss during calorie restriction, though those studies tested diets in older adults with obesity and not GLP-1 drugs.

Where the evidence is heading

Four studies are testing exercise in people on GLP-1 treatment right now. These are registry and protocol listings and not results, so check each one for updates before you cite it.

Notice that the Virginia Tech study puts a personal trainer at the center of the program, which is a good sign for where this work is going.

Stay in scope as a GLP-1 coach

You can program exercise, support movement and coach behavior, but you can’t advise on doses or tell a client to stop treatment.

Knowing the research makes you a better coach, and it doesn’t change what you’re allowed to say. Here is where NASM draws the line.

NASM gives a simple example. If a client asks whether to lower their dose because of nausea, acknowledge the concern and point them to their prescriber, then deal with what is yours, which is whether they feel well enough to train and whether to modify or postpone the session.

Health systems are building the case for exercise

A June 2026 white paper estimates that adding structured exercise to GLP-1 therapy is worth £2.7 billion to the UK over 10 years and £13 billion over 30.

FTI Consulting’s Center for Healthcare Economics and Policy built the model with a coalition of fitness trade bodies, including the Health & Fitness Association and ukactive. It compares GLP-1 therapy plus structured exercise against GLP-1 therapy alone, and it ran the same math for four other countries.

Source: FTI Consulting for the Health & Fitness Association, ukactive and partner bodies, 2026.

Become the GLP-1 personal trainer your clients can rely on

Turn the research into one routine you can repeat with every GLP-1 client.

A clear routine makes you easier to trust and easier to refer to. Here is how the research maps onto the tools you already use.

1. Set a baseline
   Record weight, a strength benchmark and how your client feels, using the body fat calculator and one-rep max calculator for estimates that don’t replace a scan or a clinician’s assessment.
2. Schedule two to three strength sessions a week
   That matches the ukactive report, and you can build the plan in the AI workout builder and adjust it for how your client feels that week.
3. Track protein against the care team’s target
   Ask the care team for a protein target, use the protein intake calculator for a starting estimate, and log meals in your nutrition coaching software.
4. Check in weekly on movement and symptoms
   Ask about steps, energy and nausea, adjust the plan if activity drops, and send the client back to their prescriber if symptoms worry you. Keep every check-in in one CRM for personal trainers.
5. Package it as a program
   Spell out what’s included, such as sessions, check-ins and who you refer to, then set the price in the pricing package builder and deliver it all through your personal training app.

GLP-1 and personal training: common questions

Sources and method

This page is secondary research. FitBudd did not run a survey for it. Figures were checked against the cited sources on October 27, 2026. Conference data and registry listings are labeled as such. This page is education for fitness professionals and is not medical advice.