I like walking. It's easy on my feet and gets me outdoors. Check backward on this blog and you'll see lots of support for walking as a way of life. Or at least as an essential component of it.
But runners are better walkers. Turns out that walking into old age isn't so great at holding off your ability to move with ease and agility. Running is.
This is a great article that outlines the research that was done into both running and walking in your mid 60''s and beyond. Runners have a similar "fitness" to sedentary college students!
Looks like I need to pick up my pace.
Read: Run to Stay Young