According to estimates from the Centers for Disease Control and Prevention, nearly one-quarter of million children and teenagers will suffer sports related head injuries over the course of the year. Most will be concussions.
Griffin Woodlief was practicing with his Pop Warner football team in Marin when he was involved in a collision.
"I was in a drill in football practice and someone hit me with the top of their helmet on top of my helmet; I and had a headache and went to the doctor and they told me I had a concussion," Griffin said.
When Griffin's headaches persisted, he was referred to Dr. Farhad Sahebkar, director of the Concussion Center at California Pacific Medical Center in San Francisco. He says that recent studies have shown the children are actually at an elevated risk for brain damage.
"It can take them a longer time to recover," he said. "Another problem we see with children is that if they suffer another head injury before they have a chance to recover, the response to that can be more serious that when we see that in adults."
The condition is known as "second impact syndrome."
Sahebkar says children's brains are especially vulnerable when they're still healing, and that a second trauma during that window can interrupt the process.
"There is a higher energy demand during the recovery process, a state of higher metabolism in the brain during recovery," he said. "And any disruption during that fragile state can cause disruption in the blood brain barrier and cause brain swelling."
It can even cause death.
Sahebkar says it can take several weeks or longer to confirm that an injury is healed. During that time, he advises patients to avoid taxing physical activity.
A recent California law also requires young players to get a doctor's clearance before returning to the field.
Griffin's father believes the new rules have sparked a culture change on the practice field as well.
"You're really glad they take that peer pressure off; these coaches with Pop Warner in southern Marin, they're unbelievable, really proactive, they care about the kids," Miles Archer Woodlief said.
And while Griffin says it was hard to be off the field, he's happy to share the importance with fellow players.
"For other athletes, if you get hit in the head and feel fuzzy, tell your coach and come off the field; you're not being a wimp, you're doing the right thing," he said.
Griffin has returned to his team in time for their playoff run.