WOW walking really does get me in shape!

I have followed Jeff Galloways training methods for a number of years. The balanced combination of walking and running in every workout has helped limit and reduce the amount of pain in my already damaged knees. It also helped me do well in several marathons and halfs.
Now that my bad knee has really been bothering me I have embraced walking as the exercise of choice. I lace up my running shoes and hit the road for a brisk walk and get the heart pumping and according to my HRM I am reaching a good training zone.
This has me focused my training as well. I do somewalks as I would train for races. Up-Tempo walks, fartleks, hill work aand sone L.S.D.

The side of this is the benefit in my head of getting out even with some pain that stops me from running. I have maintained a reasonable level of sanity by getting out a sweating on a regular basis.