Should you wear a helmet to do a headstand? Apparently, the President’s Council on Fitness, Sports & Nutrition thinks so.

The council, along with Michelle Obama’s Let’s Move campaign, wagged its finger at the United States Postal Service’s new series of stamps aimed at promoting physical activity because some of the cartoon figures weren’t decked out in enough safety gear, according to Linn’s Stamp News.

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The stamps — which had already been sent to print — include kids engaged in a variety of fitness activities: there’s a girl balancing on a rock, a boy shooting hoops, a girl swinging. But three stamps were of concern to the President’s Council. They depict a boy doing a cannonball dive, a boy skateboarding without knee pads (he is wearing a helmet), and a kid doing a headstand without a helmet.

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“The stamps are on hold with the printer and we have not made a decision at this point, right now, with respect to how we are going to move forward,” a USPS spokesman told The Daily Caller.

The President’s Council is co-chaired by former Super Bowl champion Drew Brees and three-time Olympic gymnasts Dominique Dawes. The First Lady’s Let’s Move campaign was alerted to the stamps when the USPS asked her to be involved in rolling out the new series.

It may be good news for philatelists, though: If any of the stamps survive, their value should skyrocket.