Aug. 3, 2009 -- That reliably geeky character in high school movies that falls, trips and inevitably hurts himself in gym may be lost on the next generation.
Children are showing up in emergency rooms with injuries from physical education class at more than double the rate of 10 years ago, according to a study published in today's issue of the journal Pediatrics. While the rate doubled, the annual number of injuries shot up by 150 percent, from 1997 to 2007.
The study used numbers from the National Electronic Injury Surveillance System (NEISS) -- a sample of emergency room departments designed to reflect the nation as a whole -- to weed out how boys and girls from kindergarten to senior year end up in the emergency room after P.E. class.
Middle school students took up the greatest proportion of the estimated 405,305 cases seen in emergency rooms, while just six activities -- running, basketball, football, volleyball, soccer and gymnastics -- contributed to more than 70 percent of all injuries.
"The good news is this data set we used is the best for doing the surveillance; the bad news is it doesn't always tell us why," said author of the study Dr. Lara McKenzie of the Center for Injury Research and Policy at the Research Institute at Nationwide Children's hospital in Columbus, Ohio.
"What we do know was this increase was consistent across gender and age groups, and I think it's unlikely that this increase is attributable to an increase in P.E. participation," said McKenzie.
In 1991, 42 percent of U.S. students attended a daily P.E. class, according to the 2006 Shape of the Nation Report by the National Association for Sport and Physical Education. By 2003, only 28 percent of students went to P.E. daily.
Since school systems have cut P.E. classes considerably in recent years, McKenzie argued that the extra sprains, cuts and concussions in emergency rooms must be from some unstudied social or public health factor.
Exactly what that factor is -- from increased childhood obesity to competitive training -- sparked a bit of debate among pediatricians. Other doctors questioned whether injuries were actually on the rise or if hospitals were doing a better job of keeping records.
Why ERs Are Reporting More Gym Injuries
"It may just be a matter of better reporting of these injuries," Dr. John Walburn of the University of Nebraska Medical Center wrote in an e-mail to ABC News. "My opinion is, however, that kids are fatter. ... They have less P.E. time than in the past and so are in worse shape and more injury-prone."
Dr. Lonnie Zeltzer of Mattel Children's Hospital at the University of California in Los Angeles agreed.
"I think with so much reduction in P.E. programs in general, kids are out of shape and more likely to get injured when they do play sports or other athletics," Zeltzer wrote in an e-mail to ABC News.
"And too many kids specialize in one sport which places stress on the musculoskeletal system used in that sport," added Walburn.
Whether obesity is behind the increased injuries or not, studies show children today are indeed more likely to be overweight. The percentage of children and teens that are overweight has more than tripled since 1980, according to the 2006 Shape of the Nation Report.
However the authors of the study thought of a different explanation behind the numbers -- a lack of school nurses and P.E. teachers.
"We know that the number of school nurses had declined," said Nationwide Children's hospital's McKenzie. "Without school nurses on site, more students might be sent to the emergency room for treatment."
McKenzie also hypothesized that larger class sizes in P.E. might lead to less supervision and therefore more injuries. "Only 36 percent of the schools that require P.E. have a maximum allowable teacher to student ratio," she said.
Or, McKenzie suggested, the movement known as "new P.E." might be to blame. New P.E. incorporates more adult exercise activities such as jogging, fitness classes and weights than team sports and skills learning.
"But these are all speculations," McKenzie added.
Gender Difference Is Common in Sports Injuries
One thing doctors didn't debate was the gender differences reported in the study. Boys were more likely to have head injuries, fractures or cuts, while girls were more likely to have strains, sprains and other non-contact injuries.
"With boys you see more aggressive activity that leads to more blunt trauma and forceful injuries, lacerations and head trauma," explained Dr. Amy Miller-Bohn of the University of Michigan. "With the female population, we see things more related to mechanical and anatomical issues, like strains and sprains."
In fact, Dr. Bohn has seen a major increase in sprains and other more severe injuries among her cheerleading patients. The rates of cheerleading injuries rose sixfold, going from 5,000 in 1980 to nearly 30,000 today.
As for McKenzie, she hopes her study will lead to more investigation to prevent injuries.
"I think one of the big messages from this paper is that a physically active lifestyle is important. The long-term effects of psychical activity outweigh the minor injuries," she said.