YMMV, definitely, but I think walking for a distance rather than a time preserves some of that 'wow'. I know I was fairly impressed with myself the first time I walked a mile and a half to a convenience store, walked around to shop, and walked a mile and a half home without stopping. It might be less of a 'wow' than running some distance, but for level one I think attainability outweighs that.
Here is an calculator enabling equalizing for fitness among distances and times. For example. the fitness level required to do two miles in 30 minutes is approximately the same as that required to do one mile in 14 minutes and a few seconds.
I just got this random idea that people who want to become better at life could benefit from a common scale of "leveling". No, I don't mean vague Lesswrongey things like "changing your mind". I mean a set of concrete criteria like "you qualify for level 2 if you can do 5 pull-ups, have solved 30 Project Euler problems, and did 10 cold approaches". Obviously there would be separate ladders for different character classes, but not too many. Also obviously, my example was a bit too high for level 2. So I guess I really want to ask some meta questions here:
1) Do you think agreeing on a common leveling scale would be a good thing for a substantial subset of LW users? Would you feel good about leveling up and telling other people about it on LW?
2) Is there some good way to determine leveling criteria that are neither too high nor too low? Maybe make an intermediate scale of "experience points"?