Running on Empty (shoes that is)

The question was... I have always been told to change shoes every 600 miles. Does this general rule apply to shoes used exclusively on a treadmill?
Treadmills can actually be harder on shoes then running outdoors. On a treadmill both the "road" (the belt) and you are moving creating even more shearing force on the outsole. The extra motion of the belt also requires more stability from the shoe stressing the mid-sole. One more point is that shoes companies say that their shoes last about 400 - 600 miles on average. The heavier runners might get a little bit less mileage out of the shoes and the lighter runners might get a bit more out their shoes due to the amount of impact being put on the foam of the shoe. Good news is treadmill shoes look nice and clean! Six months and or 400-600 miles is a good rule of toe...I mean thumb.