Lead author Marla Eisenberg of the University of Minnesota said a survey of more than 2,700 adolescents enrolled in middle school and high school in St. Paul and Minneapolis found 5.9 percent of boys reported using steroids and 4.6 percent of girls.
"We've got some young people and in some cases pretty young, young people -- we're looking at middle schoolers -- who say they are using some of these pretty risky substances in order to increase their muscularity," Eisenberg told Minnesota Public Radio. "And that's something we need to be paying attention to."
The researchers did not ask students what motivated them to use steroids, but Eisenberg said it's possible children were influenced by the media concerning body size.
The study, published online in the journal Pediatrics, said the study also found 90 percent of boys and 81 percent of girls said they were exercising more to increase their muscle mass.