I'm not commenting specifically on the heart-muscle aspect of the study, but it shouldn't be a surprise that the weight loss from this drug is significantly attributable to muscle loss; it almost always is when dieting. It's the same with keto/low-carb or any other kind of caloric-restrictive dieting (which Ozempic facilitates).

The modern weight-loss programs I'm seeing now (at least those aimed mostly at middle-aged men) emphasize consuming significant amounts of protein (2g for every 1kg of body weight each day) and engaging in regular resistance training, in order to maintain muscle mass.

The article addresses this:

To keep muscle strong while losing weight, Prado says it is essential to focus on two main things: nutrition and exercise. Proper nutrition means getting enough high-quality protein, essential vitamins and minerals, and other “muscle-building” nutrients. Sometimes, this can include protein supplements to make sure the body has what it needs.

Perhaps there needs to be more formal research into this, and a strong recommendation made to everyone using these drugs that this kind of diet and exercise plan is vital.

There are a lot of people here citing loss of muscle mass as a side effect of GLP-1s, when the reality is that weight loss almost always comes with muscle loss.

For me, that hasn't even been the case. I'm down 40lbs on a relatively low dose of Semaglutide and my muscle mass has moderately increased over the last 6 months. The hysteria over this is totally unfounded.

Some of the side effects of semaglutide are just a result of eating less calories.

Without a control group who also ate the same amount of calories but without the drug, it's hard to know if the side effect were directly caused by semaglutide or just a result of being in a calorie deficit.

It also decreases gut motility, which helps with the intended effect of appetite suppression. Young healthy people tend to shrug at that. As an old person that takes it right off the menu even before I read about accelerated sarcopenea. Maybe it's the same effect on the peristaltic muscles.

It may be worth considering that a heavier person needs a stronger heart than a lighter one. The heavier weight also acts as a constant load/training. Without some degree normalization we won‘t know whether this is normal or concerning.