In the changing America of leaner Chicken McNuggets and a fervency to lower the country's collective weight, getting told to shape up seems to have extended to a US government anti-obesity campaign.

Last year, the Centers for Disease Control launched a multi-media advertising blitz aimed at getting children to become more active, carrying the theme "Verb, it's what you do."

Criticised for being too vague and ineffective, campaign creators Saatchi & Saatchi have added US$68.4m to the $125m price tag and have developed more direct suggestions to exercise-shy US youngsters.

One print ad, for example, shows children playing volleyball and includes the words "Get out, go play."