A valid comment, I was actually having this discussion with another hubber yesterday morning! But as Gummibear pointed out - some people only have mtb's and to them, whether it's on gravel/dirt/tar it's mountain biking because they have knobblies on. And then like Mads stated, for those that have both road and mtb's, it's personal preference on whether they log the mileage as mtb or road. At the end of the day you're still riding your bicycle and that's all that counts. But if you're willing to volunteer yourself to go through 131 people's workouts and approximately 23000 km's per month of terrain to determine what's really a mountain biking working and what's a dirt-roadie workout, then feel free to do so!
