I just use mine to do my job and try to get by from one day to the next. I don't take them for granted; I've had plenty of thoughts/worries about what would happen if I weren't as able-bodied as I am (which is to say, enough to live normally but with less strength and energy than most people my age should have, due to health issues). I'm OK for the time being, but I've been through a period where I struggled to get from one end of the room to the next. I've been confined to a hospital bed and had to take to getting back on my feet slowly. And I know it could always happen again. I don't go out walking as often as I should now, and I'm certainly not about to run any marathons, but I think I've earned them well enough. I do what I can.