alt Hacker NewsMuscle loss is determined by your protein intake, muscle stimulus, and rate of weight loss. Plenty of people start lifting for the first time (or after having stopped for extended periods of time) when going on GLP-1s and actually put on muscle mass.
It might result in more loss of buccal fat than otherwise but even that is not definitive. Activating the receptors is not the same as burning fat - there are GLP-1 receptors all over your body in all sorts of organs. If you activate them in your brain you're not burning your brain for energy.
n=1, been lifting weights for 25 years and lost 40 lbs on Zepbound and counting.
I can still do my routines easily with no issues. My muscles look slightly smaller I think, but maybe that's the fat around them that's been diminished.