In the past, a blow to the head with potential concussion might have led to the recommendation to avoid sleep for some time. It was thought that if you failed to stay awake you would fall into a coma or lose consciousness. It was also believed that the severity of a head injury should be checked on periodically to see if there was a change in alertness.
Current evidence shows that sleep speeds brain recovery. The first days after a concussion are important to brain recovery. It is encouraged to have physical and mental rest to aid the healing process. Extended bed rest is not recommended because it decreases muscle strength and changes how your body processes energy, along with other harmful effects. After a few days rest, people with a concussion should ease back into their regular activities.