WASHINGTON (AP) â€” Researchers are split on whether repeatedly bouncing a soccer ball off a young player's head can dent the child's thinking ability.
Some studies have found that players who suffer repeated blows to the head can have impaired cognition years later. But players can suffer head injury by running into other players or a goal post, or striking their head on the ground in a fall. Experts at a Washington conference generally agreed it's too soon to blame heading the ball.
One researcher, however, said his work on crash test dummies indicates the impact of a ball is powerful enough to warrant head protection.
The conference was called by the Consumer Product Safety Commission. ``One of the interests for us is whether subtle effects are present as a result of head contact with the ball,'' said Ron Medford, assistant executive director for hazard identification and reduction. CPSC was looking for information, not trying to make soccer rules, he said.
The CPSC study was a response to research such as a study in the Journal of the American Medical Association in 1999 which reported that amateur soccer players scored lower than amateur athletes in other sports on tests of memory and planning. The researchers suspected that repeated blows to the head may be the reason. Other studies, in Europe, found similar problems in elite players.
An unpublished study presented at the CPSC conference tried to find the effect of the impact when a ball is headed. Researcher Mariusz Ziejewski of North Dakota State University tested the impact of soccer balls of crash test dummy heads, and used computer modeling to estimate what those results could mean in terms of brain injury. The balls struck the heads with 150-200 pounds of force, which Ziejewski considered to be less than those which can occur in a game.
In a properly headed ball, the forehead takes the impact, and bent knees absorb much of the force. But in an improperly headed ball, by an inexperienced player who may be caught by surprise, movement of the head creates rotational force on the brain, Ziejewski said.
Some of the impacts would be sufficient to create shearing stresses that could stretch and deform brain tissue, if the ball is not headed properly, Ziejewski concluded. ``If you execute the header properly ... the effect on your brain most likely is very minimal,'' he said. ``If you get hit in the head and you don't expect it, it could be a different story.''
Use of padded headgear could reduce the effect of low impacts to minimal levels, Ziejewski said, based on his study, which was funded through a research grant to the university from SoccerDocs, a St. Paul, Minn., company that makes the headgear.
However, knowing what happens in a crash test dummy is not the same as knowing what happens in a player's brain. And other participants at the conference questioned Ziejewski's definition of a potential injury level. Researchers can't tell the amount of impact necessary to cause mild deficits, said Trey Crisco, an associate professor of orthopedics and engineering at Brown University. Crisco and other experts also questioned whether there is a need for players to wear head protection.
There are few reported cases of concussion, which itself is not always easy to identify, and the problem of milder injuries, which was a major focus of the CPSC conference, would be even harder to pick up, Crisco said.
However, a 1998 National Institutes of Health consensus statement on traumatic brain injury estimated ''90 percent of sports-related TBIs are mild and may go unreported.'' Risk factors for such injuries are rarely studied, the report said.
Head protection conceivably could make matters worse by giving players a false sense of security, which could encourage them to take more risks, said Bill Mason, senior member of the referee committee at the American Youth Soccer Organization. If young players are hurt from heading the ball, it's probably a rare event, he said. However, he considered the issue worth watching, especially when the header comes off a ball kicked high and downfield.
The youth soccer group said that coaches should not insist that players head the ball if they don't want to, but it said teaching the skill is imperative for those who do want to.