So I've started bike riding again. Not the indoor stationary bike that I've ridden for years, the one I ride while drinking coffee and reading the NY Times :-)
(yeah, that was a real work out....LOL)
No, I've started riding an outdoor bike. I got the bike so I could do simple errands around town without using my car. But I also ride the bike around the neighborhood, just for exercise, and so I can actually ride it on those errands. In about 20 minutes I can ride up and down steep hills, from end of the area where I live to the other and back, and get a pretty good work out. By the time I'm finished I'm quite winded.
I ride the same route I walk when I take the dogs out. Clearly the walk takes longer than riding the bike...but also the route looks and feels different whether I'm hiking or biking. During the hike we are always on the look out for, well, natural wild life...bobcats, coyotes, snakes...that sort of thing. And occasionally we see them too, hunting under the scrub trees, looking for rabbits or ground squirrels.
Biking it is more arduous. The hills are steep. Going down hill is risky because of the speed but also the wind. The wind races across the arroyo and catches me as I coast at the bottom of a hill - hitting me from the side - and almost knocking me off balance.