That is an interesting idea and it follows some patterns I previously noticed with friends. The ones who are not or never were physically active are all complaining about aches and pains and acting like they are old men twice their age just doing basic household things. I kind of just chalked that up to them not being in shape, but it never really fully explained the extent of their complaints. However I grew up with a very physical life working on the farm and doing trade work since forever. By every measure I should be the one complaining about aches and pains and old injuries and such, but perhaps because im so accustomed to pains just from work and more intense physical activity the age related stuff just hasn't hit me hard enough to really notice like they do.