The sample included 35 athletes who were removed from games right after getting a concussion and compared their symptoms and recovery to 34 athletes who kept playing in the game or match after taking a hit. The study found that players who stayed in the game after head trauma took an average of 44 days to recover. By comparison, athletes who left a game immediately after signs of concussion took only an average of 22 days to recover.

While there were no meaningful differences in recovery time among girls or boys, and no differences by sport, that may be because of the size of the study. Researchers say that while the sample size was small and involved just one clinic, the results clearly highlight the importance of physical and cognitive rest promptly following concussion.

The findings may help doctors promote the message that taking immediate precautions after concussion will actually allow the athlete more opportunities to keep playing, not fewer. Resting immediately in the 24 to 48 hours following a concussion (and then slowly returning to normal activities under the supervision of a physician) reduces the possibility of further stress on the system and allows brain cells to heal faster so that athletes can get back to their sport more quickly. “It’s something that we consistently preach to coaches, parents and kids,” said R.J. Elbin, who led the study while at the University of Pittsburgh but who now is director of the Office for Sport Concussion Research at the University of Arkansas. “However, until now, there really has not been any data that supports this idea.”

Estimates show that each year in the United States, there are up to 3.8 million sports-related concussions, which can happen when there is a blow or jolt to the head that causes the brain to bounce within the skull, stretching and damaging brain cells. Symptoms of concussion may include dizziness, confusion, nausea and sensitivity to light.

Young athletes are particularly prone to prolonged recovery and complications from concussion. “The developing brain has been shown to be more vulnerable to the physiological effects of the injury,” said Tad Seifert, a neurologist and director of the Sports Concussion Program for Norton Healthcare, in Louisville, Ky.