[VLM]

I find nothing to disagree with in fasteo's reply other than to add you're going to live a long time (hopefully).

So say you're kinda frail at age 25, and everyone agrees you lose about half your muscle mass by age 75. Half of frail at 75 might be a very big problem. If you want to be healthy at age 75, in contrast to merely being alive, that would have certain implications for your goals at age 25, or 50, or 70 or whatever.

Or the TLDR is many (not all) of the health benefits of weight training show up later in life not in your youth.

Superficially, I never broke any bones in my 20s or 30s so weight training might be seen as a waste of time, but the "real" benefit of weight training is I'm much less likely to break a hip at 75. Better balance, better coordination, more muscle mass so I have to risk less, denser bones, stronger ligaments... Aside from not having a broken hip at 75, just in day to day life I'm likely to feel a heck of a lot better.