[olalonde]

You lost muscle because you lost around 1.54% of body weight per week, which is way too aggressive. The maximum recommended amount for losing weight while retaining muscle is around 1%. You will also most likely experience a weight rebound.

[rootusrootus]

Hasn't this mostly been debunked? You lose muscle mass because you lost mass overall, and whether you lost it too quickly or not is not the major factor. AFAIK maintaining muscle mass while losing fat is borderline impossible for anyone who isn't extremely fat and/or very disproportionate composition to begin with.

[kube-system]

Not at all, this is a well-known and long-established risk of rapid weight loss. Even long before any of these drugs existed, medical guidance was to lose weight slowly to help limit lean muscle loss.

[olalonde]

Not as far as I know. The ratio of fat-to-muscle loss depends on several factors, most notably the rate of weight loss (see https://pubmed.ncbi.nlm.nih.gov/34371981/). In fact, retatrutide is popular notably because it is known to preserve lean body mass better than other weight loss drugs.

[staticassertion]

> because it is known to

I thought that this was not yet substantiated in human trials? There's a plausible mechanism and, I think a mouse trial, right?

[olalonde]

Seems you are correct according to https://pubmed.ncbi.nlm.nih.gov/40609566/: "The proportion of lean mass loss to weight loss was similar to other obesity treatments."

[dcherman]

You need to define how much muscle mass you expect to lose. The entire idea behind the bulk/cut cycle is that you want to net gain muscle after a full diet cycle.

It's also not borderline impossible to maintain the majority of your muscle mass, but it depends on how you eat and train. We don't know enough about the person above's diet, training, current body composition, etc. to say anything for certain.

[Jerrrrrrrry]

GLP1 destroy muscle tissue.

[oarfish]

nope