The previous generations didn't really do exercises, rather we can call what they did hard labor. You always find them going to farms, streams and other normal petty works that we in these generation see as hard labour,
And also, the food they eat are most nutritious than what we have in our generation. They eat more of natural unlike now were we eat refined products.... I've came across a tomato farm, where the farmer was using chemical to make his plant grow faster so you tell me why this generation wouldn't grow like agric fowl. That's to say that, even aside from stress, what we take in matters alot.

If we're even to talk more on long life i think we would have to go back to the generation before father Abraham in the bible.... Where men of 100years were still strong enough to reproduce...or should we talk about Methuselah???

At the end, it seems the more the longivity of the world, the weaker human lives last💔