I think you've misunderstood GP. He's not saying they have too much muscle when they're overweight. He's saying that take that exact same amount of muscle, subtract a ton of fat from their upper bodies, then they have "too much muscle" as typically needed for their body mass. I don't agree with their phrasing, but the point isn't "nonsense."
It's a leap to suggest that it's "good" to lose this muscle mass. If you're obese then it's good to lose fat. It's even better to do so while maintaining muscle mass.
Every time GLP-1 drugs come up, the convo splinters off into topics that have nothing to do with anything unique to the drug. Now we're just talking about general weight loss and that it's good to exercise. Which is a trivial claim.
When people read "muscle loss" they think "oh it's going to make me weak and feeble".
And most obese people are below optimal levels of total lean body mass overall even before this - their leg muscles being larger than an untrained person of the same height and an average weight does not mean that their leg muscles are of optimal size, much less the rest of their body.
Sarcopenia is a real risk for any obese person who is rapidly losing weight and GLP-1s are no exception.
Also, if this is your stance, then GLP-1 is a red herring because you have the same issue with weight loss in general. Weight loss, without increasing resistance training, leads to muscle loss.
Normally that’s offset by the health effects of the exercise required to gain and maintain them as well as the lack of medical conditions that prevent exercise etc. But a fat person losing weight should inherently lose muscle mass long term assuming no changes to lifestyle.
Movement is required for the lymphatic system to function, excess muscle volume doesn’t help.
Getting to the same level of additional weight from muscles as there is from fat is also incredibly difficult. The average 5'8 person not utilizing AAS would take years of dedicated training, dialed in diet and recovery, etc., to get to 200lb at 15% bodyfat. People get there much faster and much easier putting on fat.
As to loss of muscle mass from rapid weight loss, that’s very true but slightly overstated as regaining muscle can occur ~10x as fast as it takes to grow it in the first place. Someone without a significant calorie deficit barring nutritional deficiency or other impediment will regain whatever muscle mass is required for their lifestyle quite quickly. However, people don’t train with weighted vests as among other things it targets the wrong muscle groups.
The problem here is that the overwhelming majority of people that need GLP-1s have lifestyles that are not conducive to health and have less muscle mass than would be healthy to begin with.
Which is what has me so confounded by this claims - these people already have less muscle than they should for optimal health. Losing any is a significant issue. And without lifestyle intervention, they're not going to regain any of that lost muscle.
GLP-1 drugs are phenomenal and a huge win for health outcomes. But that doesn't mean we shouldn't be telling people the truth about their downsides and what they need to do to counteract them.
In that context is this a long term downside of GLP-1 or their lifestyle?
Treating lean muscle mass as an inherent good makes sense when it’s adapted to a person’s current lifestyle. It doesn’t make sense when it’s a temporary situation.
Your body will hold on to a surprising amount of muscle. Even people that take PEDs can drop back down to natural testosterone levels and keep ~80% of their gains in the long term. (Actual gains, not the temporary glycogen and intra-muscular water retention that you see with some compounds on cycle.) It takes significant effort for them, but they’re trying to hold on to supraphysiological levels, vs. someone who is trying to hold on to what is already on the lower end of the physiological range.
No, you’re looking at the short term effects on a largely irrelevant metric (volume) while ignoring the underlying mechanisms at play.
> Your body will hold on to a surprising amount of muscle.
It’s only surprising if you ignore what going on at the cellular level. Gaining fat or muscle eventually involves gaining new cells and structures like capillaries not just increased the volume of existing cells. This is a really slow process in muscle, but those new cells stick around and can rapidly adapt to stimulus as long as you have a sufficient diet.
So yes in rapid weight loss your individual muscles cells become smaller and less capable but that’s very quick to recover. Longer term, you’ll hit the exact same homeostasis point based on stimulus and long term diet.
PS: If this seems like voodoo magic it’s simply a very old evolutionary response to starvation that predates hominid development. Being able to fairly rapidly lower energy expenditure over say winter and then recover is a major advantage.
It's an open question if hyperplasia even occurs in adult humans, and if so, under what conditions. MSC proliferation and differentiation is a thing, but none of this is actually particularly relevant to the discussion at hand.
> So yes in rapid weight loss your individual muscles cells become smaller and less capable but that’s very quick to recover. Longer term, you’ll hit the exact same homeostasis point based on stimulus and long term diet.
I'm not talking about hypothetical situations where people treat this more like a cut and then turn their lives around when it comes to resistance training and protein intake, because we know that in large part they don't. We know that a good portion of people on GLP-1 medications become sarcopenic and stay that way. And this whole thread basically started because someone was claiming that the muscle loss was good!
I'm not saying GLP-1s are bad or rapid weight loss is bad - I'm just saying you need to take steps to avoid muscle loss. And a huge amount of people on GLP-1s don't know about or understand these risks.
Do you have any evidence that long term lifestyle isn’t going to result in similar levels of strength?
> if hyperplasia even occurs in adult humans
It definitely occurs in other mammal muscle and some human tissue, and there’s studies supporting it occurring in human muscle. Myofibre splitting for example definitely occurs. https://pubmed.ncbi.nlm.nih.gov/16625366/
I’ll admit there’s controversy here, but I think the default position should be human biology is similar to other mammals unless someone demonstrates otherwise. Otherwise our unwillingness to preform experiments on humans and the expense of primate experimentation is going to create a scientific bias.