ESPN became the first TV network to run ads for the muscle-building supplement androstenedione, drawing criticism from a high school organization that the commercials send a bad message to students.

The spots, part of a new national advertising campaign by MetRx Engineered Nutrition, first appeared in the afternoon on the show "American Muscle." Stung by criticism, ESPN was reconsidering running the ads again."We appreciate the concerns of these organizations, and we will review this further," ESPN spokesman Mike Soltys said.

The ads for the supplement used by Mark McGwire will also run on Fox Sports Net's "Muscle Sport" and fitness shows on Knowledge TV. "Muscle Sport" is a time buy on Fox Sports Net, meaning the network is not responsible for selling the commercials.