I broke out the roller blades a few days ago - it's been forever since I've worn them (high school?) and you could probably tell when I first got them on. :) (think stumbling, breaking rhythm, leaning too far forward so nearly face planting...you get the point)
I think I may start roller blading instead of running. Less chance of shin splints (which is ALWAYS preferable) and I felt it more in my thigh muscles (similar to riding a bike uphill) which seems like it would be more beneficial for getting ready for RAGBRAI than running would be. My heart rate was up just as fast too! I may have to find a longer route though - it didn't take me long to get through the track.