What on earth's the matter with you lot? Feeling old at 22, all downhill from 30, trashed kneecaps at 25? Or even at 52 seems a bit young to me, but maybe warship decks are a particular hazard, I don't know. I suppose if the deck is rising when you put your foot down, it could be a bit traumatic. Pavements are hard, but at least they keep still.
The human body, I read, is designed to deliver trouble-free service up to about age 35-40, so you kids are nurturing hypochondria and/or neurosis if you really think it's already going downhill. After 45, it's reported, people start noticing that getting out of bed in the morning isn't the leaping start to the day it used to be, and they often say "Aaaaah" when they sit down or "Oooofff" when they get up again. I always make a point of performing these actions silently, though that probably doesn't fool anyone, but then I'm over 60. After 50, research suggests, people think about their own death about once a day. This leaps to about 3 times a day at 60. After 85, you hear about the death of others and merely chuckle, even if you liked them and are very sorry, because you're still here.
In my experience of knees, it's never going up that is the problem, whether a slope or stairs; it's going down. And in the words of my cheerful GP, if you want to live to be a drooling, incontinent, idiotic 90-year-old nuisance, don't smoke or drink, take moderate exercise, and eat up your vegetables. If you'd rather avoid this almost inevitable scenario, and spare your children, then just have a good (albeit shorter) time.
