I've seen it happen with people even prior to the GLP-1s - prior to an injury derailing my last attempt to lose weight, I lost 30lb at an even faster rate and had 3 DEXA scans showing consistent increases in LBM.

This conversation does make me wonder about whether or not it would make sense to make the option available for people to go on exogenous testosterone (and yes potentially even women) while on these to help prevent muscle loss.