From National Geographic:
Poor Rapunzel. Not only did she get locked up in a tall tower, but she literally risked her neck by allowing a prince to climb up her hair. Such dilemmas had long bothered Sue Stocklmayer, director of the National Centre for the Public Awareness of Science (CPAS) at the Australian National University in Canberra. Stocklmayer resolved to do something about it, so she and fellow CPAS staff member Mike Gore, a retired professor, channeled their frustrations over fairy tale physics into a traveling science show.
Rapunzel’s conundrum is one of the highlights of the show. “We ask how it is that Rapunzel didn’t lose her skull, given the weight of what she’s [supporting],” Stocklmayer said. “You might notice some of the enlightened [storybook] artists have cottoned on to this and show her wrapping her hair around something, like a bedpost, first. “A small object”—such as a cooped-up princess—”can bear a lot of weight if the connecting device [her hair] is wrapped around something.” The prince is then technically hanging on to the bedpost rather than Rapunzel’s scalp. “So long as Rapunzel wraps her hair first, then the prince and she are Ok,” Stocklmayer said. “So in her case, yes, it could happen.”
More here.