I walk a lot due to my work. But it's on concrete, so not great for the knees....I probably clock anywhere from 2-4 miles a day on concrete, this includes .....several stairways totaling 1,000 steps (I counted them) going down to an elevation of 143' and up to 252'
I took Glucosamine and also it starts with a C can't remember.....it worked for a while and then just didn't seem to work anymore. I found that good shoes are the ticket. I wear soles out on my work boots every year at the heel throwing thing's out of whack and I'm sure stressing joints. I start feeling it in my knees when it's time to replace my kicks.
Keep moving is my policy.