As 90 women contestants in last Sunday's annual race around Paris for cafe waiters and waitresses found out, high heels can be treacherous.
The rules of the race don't say that women have to wear high heels. They simply say: "Tenue de travail obligatoire" - that is, "wear whatever you are required to wear at work."
For men (garcons), that's a white shirt, a black bow tie, a starched white apron or black vest, white socks, and sensible black shoes. For women (serveuses), it's white shirt, black bow tie, short black skirt, and black shoes with heels.
Not towering heels, mind you (although there were a few pairs of four- or five-inchers). But high enough to cause a bobble or two in a five-mile sprint around Paris balancing a tray with three glasses and a bottle of Perrier.
The men who finished the race did so in good form. But more than one serveuse limped across the finish line with bare or battered feet - Perrier bottle and glasses intact, but shoes in hand.
The winning waitress wore wingtips: solid, black, very flat shoes. "We're allowed to wear these at our hotel," says Maria Pehrsson, who hails from Sweden's Restaurangernas Dag.
The No. 2 woman finisher, Therese Siggelin, also works at the Restaurangernas Dag and finished first in the race last year. But this year, she wore shoes with three-inch heels. "I trained less this year," Ms. Siggelin explained. "And last year, I wore flat shoes."
As French waitress Nasabia Mzenogize loped across the finish line, a race official in a bright yellow jacket called out to the crowd on City Hall plaza that she was "lighter than a gazelle!"
'"You're very beautiful, mademoiselle," he added over City Hall's public address system.
If Ms. Mzenogize appreciated the compliment, she did not appreciate the high-heeled shoes. "I don't like them," she said. "They make my feet tired."
The average French waitress walks about 20 miles and hauls 400 pounds in the course of a working day. But the managers of France's 50,000 cafs appear to share the view of race organizers: "Bannis les baskets! Fonction oblige!" ("Banish sneakers! Duty requires it!")
Running shoes had their day on the streets of Paris, even in some of its cafes, during the city's nearly month-long public-transit strike last December. But the habit of wearing sneakers to work never really caught on.
"We all saw American women wearing sneakers to work in the movie 'Working Girl,' but that would never be accepted in France," says Karin Dufau, a Parisian office worker who wore regulation two-inch heels with her business suit.
Her views are shared by Le Monde, which last week took American women to task for being "at ease in their baskets," source of "a debatable esthetic."
But until you try running five miles in high heels with a tray of Perrier and glasses, don't knock running shoes.