[mikestew]

Running is probably the worst sport as far as caloric expenditure is concerned.

Yes, running is extremely inefficient. The most efficient form of movement known is a human on a bicycle. One's choice depends on whether the goal is to burn calories, or travel efficiently.

I've burned an estimated 5000kcal daily on the bike for weeks.

Wait a minute, what? You're going to take the most efficient form of locomotion and use that as an example of how to burn calories? The only reason you burned that many calories is because you spent all day on the bike. Maybe I'm completely missing your point, but for time spent, running burns more calories.

[iramiller]

Rate of calorie burn on a cycle is highly dependent on speed. Riding at 32km/h or higher absolutely consumes significant energy due to wind resistance.