My Opa is struggling right now- mid 80s, thinking is getting very fuzzy, and he isn't exercising the parts (back) he needs to. It's causing his body to break down. The cartilage and disks in his ribcage and spine are collapsing, forcing him to hunch deeply (accelerating the degeneration) and crushing his lungs. If he had kept his back strong, it would have kept the stress off his tissues for decades. He would still be losing his sight, smell, and taste (horrible, for a chef), but maybe he would be less fuzzy.<p>My Opa is also the most hardcore motherfucker I've ever met. It's not that he didn't exercise. He <i>still</i> heaves around 80 lb bags of sand, he's building a goddamn cottage almost by himself, he's still almost immune to pain. He's the toughest man I know, and even on the days he has trouble with fairly basic spatial tasks he can multiply three digit numbers in his head faster than I can write them down. His short term memory is still better than mine. He's still smarter than me. He's so stubborn he keeps falling off ladders every week because despite how much he has lost he just refuses. to. give. up.<p>I can't understate how fucking scary it all is. The man is unstoppable when he puts his mind to something. Time has not worn down his will even a tiny bit. He breaks bones more often now, but he shakes it off, does the PT, and it's like it never happened. But even that isn't enough when age decides to take you. If your spine wilts, all the exercise and work in the world will not save you. When you can't sleep more than two hours at a time, what do you do? You can't force yourself to sleep. You just slowly go nuts, a little more each day.<p>Aging is the real process of senescence, not just of getting older. Dementia, weakness, and frailty all seem increasingly like symptoms of a larger bodily/immune system degeneration. The inability to exercise, the constant pain, the <i>constant</i> sleep deprivation- those things could give dementia to a young man too. You can stave off the bodily decay <i>until</i> you start aging, but not after. Some lucky few, the Jeanne Calments[1], seem to be basically immune to senescence. They follow the path you'd expect, of a body slowly wearing out. The rest of us eventually hit a point where our bodies suddenly start to break down, and things like exercise just no longer produce the same changes they used to. The systems that handle growth, repair, immune responses- they just stop.<p>I'm sorry if this is bleak, but it hurts to see him like this. I just spent a couple months helping him put up siding. He wants to finish that cottage so much. I hope it's not his swan song.<p>[1]: <a href="https://en.wikipedia.org/wiki/Jeanne_Calment" rel="nofollow">https://en.wikipedia.org/wiki/Jeanne_Calment</a>