Does anyone use older running shoes for track workouts? I have a pair of Adidas Adios 4s which I don't use for road running anymore as they're a couple years old and don't have that pop to them that they used to, but they also have no visible signs of wear and tear and seem perfectly fine. Since running tracks are easier on the legs, would it be fine to wear them for track workouts since I don't have to worry about deterioration of the cushioning leading to injuries like I would on harder surfaces?