We've heard the advice time and time again: In order for kids to heal from a concussion they need rest — lots and lots of rest. But as part of new guidelines for treating children with concussion, the Centers for Disease Control and Prevention recommends that children gradually return to non-sports activities after no more than two or three days of rest.

This is the first time the CDC has addressed pediatric concussion care and includes 19 sets of recommendations that that cover diagnosis, prognosis, management and treatment.

This isn't the first time that health experts have contradicted age-old advice about concussion and rest.

In a 2015 study from the Children’s Hospital of Wisconsin, researchers found that kids aged 11-22 who were prescribed strict rest for five days after a concussion actually reported more symptoms than those told to rest for one or two days. Stricter rest periods — such as using the cocoon method of recovery — also resulted in a slower recovery.

To be clear, none of the participants in this study were admitted to the hospital for their injuries. Rather, they were treated in an emergency room and sent home with recommendations from the staff to rest for a designated period of time.

More rest, more physical symptoms

For the study, lead researcher Danny G. Thomas, a pediatric emergency medicine doctor at Children’s Hospital of Wisconsin, and his team followed 88 young patients who were treated and released from the emergency department at Children's Hospital of Wisconsin for concussion. The patients were advised to rest for either no more than 48 hours or for five days. Each day, the patients rated their symptoms and took computer and paper tests to track their recovery. There was no difference between the two groups when it came to brain function and the ability to maintain balance. But the difference came in the patients' reported mental and physical symptoms.

Thomas reported that patients who were told to rest for longer periods complained of more physical symptoms like headaches and nausea in first few days, and more emotional symptoms such as anxiety, irritability and mood swings over time.

Researchers acknowledged that recovery from any ailment — particularly a concussion — may be different for each individual. And any return to activity that could result in another concussion should only happen after the patient has been given the OK by a doctor trained in concussion management. But they feel that their research confirms that resting for longer than 24 to 48 hours is not beneficial for most young patients and that the use of cocoon therapy, in which patients lie in a dark room for multiple days, should not be prescribed for younger patients.

A 2016 study, however, finds that those first few minutes after a concussion really matter. Researchers discovered that high school athletes who kept playing right after a concussion ended up taking nearly twice as long to recover as those who immediately left the game. The study, published in the journal Pediatrics, tracked the symptoms of 69 teen athletes: 35 who were immediately removed from the game after receiving a concussion and 34 who kept playing. Researchers found that those who stayed in the game took an average of 44 days to recover, while those who left immediately after signs of concussion took an average of 22 days to recover.

Editor's note: This story was originally published in January 2015 and has been updated with new information.

More rest may not be better for a concussion
Research contradicts age-old advice about rest and recovery after a concussion.