hildren who watch major sporting events on television see a lot of violence and unsafe behavior, and it is not just on the field.

Researchers who examined commercials on the broadcasts reported yesterday that about a fifth depicted images that could have bad influences on younger viewers.

The study appears in the journal Pediatrics. Its lead author, Dr. Robert F. Tamburro, said he did not know whether sporting events carried a disproportionate number of commercials with questionable imagery. But he said he had focused on them because many viewers were young.

"I think a lot of people think a sporting event is pretty safe TV," said Dr. Tamburro, who did his research while he was at St. Jude Children's Research Hospital in Memphis, but now is at Penn State Children's Hospital.

He said a review of 1,185 commercials broadcast over a one-year period during the Winter Olympics, football, baseball, basketball and other sports suggests otherwise. Fourteen percent showed unsafe behavior (defined as "any action that could have harmful consequences or that contravened the injury-prevention recommendations of national organizations"), while 6 percent showed violence.

Dr. Tamburro said the unsafe behavior included riding a bicycle without a helmet, riding in a car without a car seat and crossing a street without looking. The violent images were generally in commercials for movies or other television shows.

Not all sporting events were equal. The greatest number of commercials depicting violence or unsafe behavior was shown during the Super Bowl, the study said. The least violent were shown for the Masters Golf Tournament, which had no violent commercials at all, the researchers said.