Slowing down

A long time ago I read somewhere about an exercise in which young people were physically restricted in one way or another so that everything they normally did they had to do slower and the result was that their behavior mimicked that of an elderly person.  More than anything else, as you age you slow down.  It's a biological imperative and there is nothing much you can do but learn to live with it.  So here's an something you younger people can do to see what you are in for. 
  Restrict the use of your dominant hand.  Wear a heavy work glove so that you have to depend much more on your left (if you are right handed) hand.  Tape one of your knees heavily so it doesn't bend easily and you are unable to walk rapidly.  If you wear glasses, don't wear them and if you don't, find a pair of cheap reading glasses and put them on.  Now, go about your day.  Attempt to hurry through the supermarket shopping.  Try to use your cell phone.  Drive your car.  Get money from an ATM.  Pay your bill with a debit card.  Stick to it for three or four hours.  Go ahead and discover a bit of what it is like to be normally healthy and 75-80 years old.    The rusty machinery is slowing you down. And now, remember that things of this sort are taking place in your brain as well.  It's more of a chore to remember things.  You can but it's just a lot more work.  It's more difficult to make decisions.  You get more easily confused.  You get tired and your brain thinks how nice it would be to sit down for a rest in a nice comfortable chair or to take a nap. 
    Admittedly, everybody ages differently  Some people at 55 are well into their dotage and some 80+ year olds amazingly young but every 80 year old is a slowed down version of their youth.  Believe it.