They are as much a part of growing up in America as blueberry pie and drive-in movies. But new research shows that cheerleaders, who once dazzled with their smiles and sequins, are at greater risk of serious injury than American football players.

Instead of just cheering on their team, cheerleaders are now encouraged to compete in high-stress competitions, where dangerous throws and tumbles reminiscent of gymnastics are the norm.

Because the pastime is not regulated like a sport, accidents are common and cheerleaders are swapping their pom poms for crutches, knee braces and ice packs.