NEW YORK, June 11 (UPI) -- Soccer players head the ball six to 12 times a game, and the cumulative damage from this can cause brain injury resembling concussion, U.S. researchers say.
"We studied soccer players because soccer is the world's most popular sport," Dr. Michael L. Lipton of Albert Einstein College of Medicine of Yeshiva University and medical director of magnetic resonance imaging services at Montefiore, said in a statement. "Soccer is widely played by people of all ages and there is concern that heading the ball -- a key component of the sport -- might damage the brain."
Lipton said soccer balls can travel at speeds of more than 50 miles per hour and during practice drills, players commonly head the ball 30 or more times. However, the impact from a single heading is unlikely to cause traumatic brain damage such as laceration of nerve fibers, but repetitive heading could set off a cascade of responses that leads to degeneration of brain cells over time, Lipton said.
The researchers used diffusion tensor imaging, an advanced MRI-based imaging technique, on 37 amateur adult soccer players with a median age of 31, who played the sport since childhood. They reported playing soccer for an average of 22 years and had played an average of 10 months over the previous year.
"The DTI findings pertaining to the most frequent headers in our study showed white-matter abnormalities similar to what we've seen in patients with concussion," Lipton said in a statement.
"Our study provides compelling preliminary evidence that brain changes resembling mild traumatic brain injury are associated with frequently heading a soccer ball over many years," Lipton said.
The findings were published online in the journal Radiology.