@polllyanne
Hi,
I will have to disagree with you about stretching if you, as I am, are in the habit of stretching every single day...walk or not. Stretching is a big part of my gym class and I stretch throughout the day and first thing in the morning routinely. If you are not use to walking, I would still advise light gentle stretching. I think this will make you more flexible when you start the walk. and may reduce any injury. Runners do it all the time. Each person is different and it depends on what shape you are in.
The emphasis is on gentle stretching which not everyone knows how to do properly. Once you get use to doing it the right way (you shouldn't be feeling any pain) you can increase the intensity.

FL Mary