Pédaler dans la semoule

Literally: To pedal in the semolina

Example: “Depuis le début de la réunion, on pédale dans la semoule sans rien décider.” — Since the meeting started, we've been going around in circles without deciding anything.

English equivalent: To spin one's wheels

Origin: From cycling, early 20th century — and semoule (semolina) was not the original grain. The phrase started as pédaler dans la choucroute: sauerkraut used to be made at home by treading the cabbage underfoot to pack it down, and a cyclist who could no longer make his legs do useful work looked exactly like a man stamping fruitlessly in a barrel of it. Pédaler itself, per the FEW, comes from an Old French verb meaning to tamp down with the foot, from Latin pes, pedis — foot. Sauerkraut eventually lost out to semolina in most of the country, though pédaler dans la choucroute and even dans le yaourt both still turn up regionally.