Competitive surfers are less likely to be injured than those playing college soccer and basketball, according to a report in the American Journal of Sports Medicine.

Researchers at Rhode Island Hospital and Brown Medical School computed the rate of injury among competitive surfers to find there are about 6.6 significant injuries per 1,000 hours of surfing. They analyzed the injury data from 32 surfing contests worldwide, both professional and amateur.

There are about 19 injuries per 1,000 hours of participation in men's college soccer and nine injuries during that time for basketball players, according to www.LiveScience.com.

Sprains and strains to the lower extremities, especially the knee, were the most common injuries suffered by surfers, researchers found in the article printed in the journal's January issue.

"This is likely due to the aggressive turning and aerial maneuvers, which score highly in competitions, but also appear to place high stress on a surfer's knee," said lead author Andrew Nathanson, an emergency medicine physician at Rhode Island Hospital.

Significant injuries included those that prevented the surfer from surfing for one or more days, resulted in a hospital visit or required on-site suturing.

But the risk of injury more than doubles when surfing in large waves or over an area with a hard bottom, Nathanson said.

In his other studies, bruises and lacerations were found to be common due to the direct contact between a surfer and a surfboard, he said. But since there are less surfers in the water during competitions, those injuries are less common in the events, he said.

Nathanson said establishing an injury rate helps the insurance industry and schools interested in starting a surfing team, and it could help determine the medical staff needed at contests.

The study was funded by the University Emergency Medicine Foundation.