1. I would'nt do it, maybe for older people who enjoy running, but they would look really stupid. I say anybody who is fit enough (or that has joint problems) to run should be able to ride a bike which is without a question better.
2. I know I have seen you before on Yahoo Awnsers, and from what I have read you seem to know a lot about bikes. You look new, so welcome to Bike Fourms
2012 Trek 1.1
2011 Trek 7.1 Fx
yeah that is me
i get tired of all the boneheads over there
what color is good for a chain ring, what is wrong with a gmc denali , does this bike make my butt look big, how far away is 10 miles, my friend stole a bike, how do you paint a bike, what color do i like, i invented a new bike that you don;t have to hunch over to ride, can i put wheels on my weedeater..
Intended as a substitute for running, not cycling (because some aging or chronically injured runners will always badly want want to 'run', vs any other activity). The superficial shape and name are misleading.
Basically, a 2-wheeled version of a RaceRunner. RaceRunners look a bit like trikes, but are actually running frames for athletes with disability (and yes, there are RaceRunner competition events, complete with World Records). http://racerunning.org