Originally Posted by Gummee!
Two werds: trail run.
Easier to get ready than riding, you can usually find some trails out the back door, AND you get tired a LOT faster than riding... A good workout may take an hour start to finish.
I'm getting there. During the long weekend we just spent in Acadia, we did only a little biking, but lots of fast-paced hiking. It was fun, especially the really steep rocky stuff; At times it felt almost like this weird amalgam of running, mountain biking and rock climbing.
Unfortunately, no trails right out my back door. The closest place that'd be good for trail running is also the closest place for mountain biking. And the easiest way for me to get there is on a bicycle... Still, after the fun I had on foot this past weekend, I plan to get over there and check out some of the rockier trails (which are closed to bikes) on foot.