The question came up in a forum about when you are too old to jog?

This is my answer.

I am 64 soon, I have osteoporosis of the spine.  3 compression fractures of the spine pre osteoporosis of the hips, regurgitating heart valves, arthritis of the feet following all the bones in them having been broken a crushed right leg fixed up with skin grafts, I need to make sure are never injured,  (this is starting to sound comic, even to me), scared lungs, and I’m now on the waiting list for surgery for a growth which we are assuming is benign, but is causing problems.

I JOG.

I will be too old to jog the day I can’t.

Get GREAT shoes, don’t skimp on the cost.

I actually do as much running as I can on soft surfaces like beaches and soft grass.

Do you know I learned I had osteoporosis with a shock in Jan of last year. That is when I took up jogging, jumping and weights as directed by the osteoporosis association of Australia. 

I have since achieved a certificate in bone health.
I then discovered that walking and bicycling is useless for protecting bone density and we NEED high impact exercise, so our bones get the message to keep building new bone tissue, if we do all this low impact stuff I was advised to do in my mid life, we get to our senior years, with osteoporosis because we have been giving our bones the message, they are not required any more, slow down, age, let the osteoblast (the cells that build new bone) die off.
If you do not use it you lose it. 

It does not matter if it is weight work, including jumps or jogging but mid life and senior people NEED to do high impact work, obviously within the restrictions of what they are capable off and how serious any pre existing condition is.  Get a personal assesment from an expert before taking generalized advise. Obviously if bones are already too fragile, imact of any type might be the worst thing, so get the best information but I do know that wapping yourself in cotton wool is not the best thing for an aging body unless you want to age faster.