There are about half a million high school cheerleaders in the United States.  Studies have shown that high participation in the activity, coupled with its year-round nature, lead to a higher total number of concussions in cheerleading than in many other sports. USA Cheer and the AACCA are partnering with the CDC to raise awareness about concussion in cheer.

The linked article contains some great links to information for parents and Return To Play resources for coaches:

http://www.prnewswire.com/news-releases/spirit-and-safety-meet-in-new-cdc-heads-up-concussion-in-youth-sports-partnership-125560883.html