A motor vehicle according to an exemplary aspect of the present disclosure includes, among other things, a running board assembly including a deck, and a linkage assembly configured to guide movement of the deck. The vehicle further includes a motor configured to move the linkage assembly to adjust a position of the deck, and a sensor configured to obtain information indicative of activity adjacent an exterior of the motor vehicle. Additionally, the vehicle includes a controller configured to interpret the information from the sensor to determine a length of at least a portion of a leg of a person. The controller is configured to instruct the motor to adjust the position of the deck based on the determined length.