Studies show that vigorous exercise has the most positive effect on the list of health benefits. The same studies also show that moderate exercise shows measurable benefits. And, I know from personal experience that it's more sustainable when it's fun.
My mother passed away from heart disease in 2010 and it was a stark lesson that unless I started to get my heart and body in shape I may be headed down the same path. I dubbed my new personal initiative RIS Walk 60 -- daily 60-minute walks to the heartbeat of DC.
I've discovered that walking, in a purposeful and conscious way, is the walking that has the most magical of all benefits, because it connects you to a higher spiritual place, a source of unlimited possibilities.