I don’t understand the second question, as you’ve got it framed up like a dichotomy but working out is being part of an athlete playing a “traditional” sport, whatever that is.

I think the trend of more men working out these days is, consciously or unconsciously, due to the general unavailability of decent affordable medical care. Keeping “fit” is a way to feel like you still have some measure of control. Another aspect of it is the fact that the concept of masculinity in our culture is going through a crisis, and conforming to the body standards invented by protofascist and eugenicist Eugen Sandow is a form of gender affirmation (which as a trans person i think is incredibly important to anyone’s mental health, cis or trans).

basically it’s the dudebro world counterpart to the “yoga wellness and alternative medicine” thing.