Can cars be parked on these (or any vulcanized rubber) without deforming/causing indentions in the rubber? I'm thinking of adding these mats to my garage gym but still parking my cars in the garage when not training.

Our 3/4" Shock Mats can handle a car going over them on a constant basis. The only thing that you will affect the mats is if there is any oil spilled on them from the car. Over time, this oil will break down the mats.