While I haven't yet graduated to loose gravel, I know some have. I can do chipseal and mild gravelly trails now, and common debris and even broken glass from cars, although not bottles, doesn't bother me in the least. The worst is the odd, stray, sharp rock on top of smooth asphalt or cement that pops up when you least expect it. As in almost everything else, the ability of our bodies to adapt is amazing, given time.Am I going to be able to run over the loose gravel? God that stuff hurt.