Yep. Hiking and biking use somewhat different muscles. This is why my daily hikes didn't have me in shape for a 100k ride, whereas Trek420 who finished in half the time I used on 43miles was panting trying to keep up with me walking up Warrington Road. It is also why I plan to alternate my workouts, both the daily commutes and the weekend longer treks. I wanna be in shape for both ... or, well, somewhere near in shape for both, even if it means not being in super shape for either.