Honestly, I'm not positive myself. All I can say is that overworking your joints without enough cool-down time will put you at high risk for arthritis.
The corticospinal tract carries motor signals from the primary motor cortex in the brain, down the spinal cord, to the muscles of the trunk and limbs. And The corticobulbar tract carries efferent, motor, information from the primary motor cortex to the muscles of the face, head and neck.
