"If you watch what we do, it kind of mimics a circus act," says Joelle Antico, of the World Cup All-Stars. "The skills that we are performing, they are risky skills."
Antico and her mother Elaine Pascale run a competitive cheerleading gym, where the teams cheer for no one but judges at often-televised contests.
Pushing the limits of gymnastics and dance, competitive cheerleading drives school cheerleaders to put on just as good a show to rev up the crowds.
"I loved cheerleading," says Rechelle Sneath.
Sneath made the team at San Jose State University last fall, doing stunts like the basket toss, a routine millions of cheerleaders perform every day.
"You're just thrown in the air basically," says Sneath. "You're supposed to look pretty and 'ooh and ahhh' and get the crowd going."
But just months into her freshman year, the stunt went wrong at practice and Rechelle became the second cheerleader this year left paralyzed.
"I was just praying because I wanted to be OK, and then they said I broke my back," she says.
In girls' sports, more than half of the catastrophic injuries - those causing paralysis or death - are happening on the sidelines, in cheerleading accidents.
"People have no idea what the competitive cheerleading involves," says sports medicine pediatrician Dr. Sally Harris.
Harris says cheerleading injuries are usually far more serious than those in "officially recognized sports" because this "activity" doesn't always get the support it deserves.
"They may not get the level of coaching and training that you would see in women's gymnastics for example," says Harris.
In professional gyms, coaches are specialists.
In schools, the coach might be doing double duty as the math teacher.
"In terms of safety, it's still the person in charge," says Pascale. "It still goes down to that individual that is standing on that floor watching those cheerleaders."
Winning requires stunts, but some schools are reconsidering the cost.
"It adds to the excitement of cheerleading very, very much," says Pascale, while observing a cheerleader routine.
Asked if she's sure it's safe, Pascale says, "Well we're sure with these girls because we're training them."
Sneath's school banned aerial stunts for now, and her family is planning legal action while she re-learns life's simplest steps.