I ride a multi-geared mountain bike. I think it has 20 total gears. For the most part, I ride in 19th gear. What I'm wondering about is what would be more beneficial... riding in a low gear or a high gear (if I'm trying to burn calories).
I used to think that riding in a low gear was better, because it seems like you're doing more work. However, there's obviously much more resistance in a much higher gear, so I think my thinking may be off. Based on anecdotal evidence from riding an exercise bike at a gym (remember, I'm riding an outdoor bike, now), it seemed like I was burning a lot more calories with more resistance. Ergo, I'm led to believe that a higher gear is the way to go.
The only reason I'm still skeptical is because it doesn't seem like I break out in a sweat very often on my bike ride, despite the fact that I go 15-17 miles on a ride and for usually 60-80 minutes at a time. That may not sound like a very good pace, but you've got to remember that this is in-city bike riding so I have to do a lot of stopping and whatnot.
I guess my goal is to ultimately just drop fat and get toned and into shape.