This is a question I've pondered for quite some time and I guess I just have to ask out loud: if a perfectly viable sidewalk is present, why would you run on the road?
Let me explain the motivation for asking. I live in your typical midwestern suburban subdivision...plenty of sidewalks, plenty of traffic on the one lane roads. Perhaps because I'm near almost all of the schools in our community, traffic can be very intense at times and , no doubt, many of those cars are filled with teenagers engaged in usual teenager distractions. Not to mention parents dealing with cell phones, kids, coffee, and their favorite radio station.
Now, I understand the benefit to running on the packed dirt on the side of the road as opposed to the hard concrete of the sidewalk. Believe me, whenever my knees ache a bit after a long run, I wonder about the pounding they took every step of the way on the concrete. On a typical run, I'll pass 3-4 people running along the side of the road during this intense period of post-school, post-work traffic while I scamper by 8 feet to their right on a safe, smooth, well-lit sidewalk. I've watched the cars come to almost a complete stop because they couldn't veer into the oncoming lane due to an opposing vehicle. And I've seen other cars make the veer with little warning or window to make the move. Now, I've driven on these same roads thousands of times myself and, being a runner, I am very diligent about keeping an eye out. However, I can't say that there haven't been times where I've been momentarily distracted enough to find myself kicking up dirt and gravel along the shoulder and thinking "thank God there wasn't somebody there." And, at night, forget about seeing anyone on the side of the road if another car is blasting their headlights in your eyes.
My point is...why would you put your safety into the hands of hundreds of potentially distracted drivers when you can control it yourself? Sure, my knees may not last as long...maybe 15 years from now I'll be kicking myself (if the prostheses allows ofcourse) for not saving my knees and joints the wear and tear. However, I may also have successfully avoided being run down in the street by a 2004 Pontiac Grand Prix whose driver dropped their CD case on the floor moments before coming upon me.
I guess we all have choices to make. Certainly, the roads, the availability of another option, the intensity of the traffic, the degree of your death wish all play a factor in your decision on where to run. For me, while my knees hold up, I'll be on the sidewalk. The road runner may be glancing at me with that knowing he-is-killing-his-knees smile. That's okay. Because I'll be looking at that approaching SUV and hoping the driver is paying attention.