Concern is growing over concussions in sports like football and boxing, and now a new survey finds that water polo players may be at risk for them as well.

More than a third of water polo participants reported sustaining a concussion either during games or in practice, according to this first-ever poll conducted by University of California, Irvine (UCI) researchers.

In recent years, there has been growing awareness of the risks of head injury in athletics, and understanding the nature and prevalence of sports-related concussion is a major focus of both clinical and basic research. In 2012, the NCAA began tracking water polo concussions, but only a handful of teams supply data, and the results haven’t been made public.

The research team polled more than 44,000 USA Water Polo members, asking about concussions, head impacts and symptoms commonly associated with concussion. More than 1,500 completed surveys were received. Thirty-six percent of respondents (30.8 percent of males and 43.5 percent of females) reported at least one concussion during water polo play, with an average of 2.14 concussions per person.

Among player positions, goalies logged the highest rate of head injury. Forty-seven percent said they’d suffered at least one concussion, with an average of 2.49 concussions per person. A majority of these head traumas occurred during practice rather than games, when defensive players are present and interposed between offensive players and goalies.

The researchers noted several limitations of the study, including the small number of respondents – fewer than four percent of the estimated water polo players in the U.S. responded.

“These numbers suggest that playing water polo carries a significant risk of concussion,” says Dr. Steven L. Small, professor and chair of neurology at the UCI. “Our results speak to the need for systematic concussion reporting in water polo,” he added.