I personally think walking is one of the best exercises a person can do. It's not hard on the joints like running is, and just about everyone can do it. I used to walk all the time, but I gradually quit. I need to get back into it.
It's a very good and easy way to exercise, I agree and if you have a dog, taking it for walks means that you can't take a day off. I'm trying to encourage my son to walk everywhere rather than expect to be driven.
Our kids have been wanting a dog for awhile. Having a dog would get us all out for walks together regularly, which I know would be good for all concerned on several levels.
Family bike rides are really excellent too. It's a shared experience, and it goes at a nice natural pace so there's plenty of time to take things in together along the way.
I agree what walking is an excellent exercise. I used to run or jog when I was younger but now I prefer to walk, as it's less physically demanding than running or jogging.
