The science on GLP-1s, muscle, and how to protect what you keep.
In plain English. Cited. Updated when the science updates. Free to read, free to share.
4 articles · cited · last updated 2026-06-10
What GLP-1s do to your body
GLP-1 receptor agonists suppress appetite and slow gastric emptying. The result is significant weight loss — and, without intervention, significant lean mass loss alongside the fat. Here is what the studies show, drug by drug.
Mounjaro vs Ozempic vs Wegovy — the comparison
How tirzepatide (Mounjaro / Zepbound) compares to semaglutide (Wegovy / Ozempic) on efficacy, side effects, cost, and muscle preservation. Drug-by-drug, evidence-based.
GLP-1 side effects, week by week
What to expect from Ozempic, Wegovy, Mounjaro, Zepbound, Rybelsus, and Saxenda — week by week, dose by dose. Nausea, fatigue, GI symptoms, and when to call your doctor.
Do you lose muscle on a GLP-1? What the research shows.
Without intervention, 25 to 40 percent of weight lost on a GLP-1 can be lean muscle, not fat. With adequate protein and resistance training, that figure drops substantially. The cited evidence, in plain English.
How to protect your muscle on a GLP-1
Lean mass loss on a GLP-1 is largely preventable. Three levers — protein, resistance training, and avoiding extreme calorie deficits — drop muscle-loss share from 25 to 40 percent to under 10. Here are the protocols, the evidence, and what Muscle Guard tracks for you.
Sources, cited and dated
Every claim in the Research Hub links to its peer-reviewed source. We change anything we get wrong. Email research@muscleguardglp.com if you spot an error or have a study to flag.