They should leave the game for the day if they lose consciousness or have persistent or delayed symptoms, according to new concussion guidelines based on the latest scientific research and endorsed by six major medical organizations.
Experts define concussion as an alteration of cerebral function.
Rest, sleep, protection from additional impact and abstinence from alcohol can allow the brain to heal. Meanwhile, symptoms that are delayed, that are more severe or that become worse over time can signal serious problems, including blood clots in the brain. Most sports-related concussions occur in people between the ages of 15 and 24. No reliable statistics exist for the number of concussion victims who had a second brain injury soon after their first concussion, but research strongly suggests that such repeated blows to the brain are likely to cause lasting damage. The CDC estimates that there are 500 deaths from sports-related traumatic brain injuries each year, though it is not an official classification for cause of death.