Three-time Olympic gold medalist Aly Raisman is calling out an airport security worker who she says questioned whether she had enough muscles to be a gymnast.

Raisman posted on Twitter Wednesday that after a female Transportation Security Administration worker said she recognized Raisman by her biceps, a male employee said, “I don’t see any muscles.” Raisman called the encounter “rude & uncomfortable.”

Raisman, who turned 23 today, says she works “very hard to be healthy & fit.” She says that if a man can’t compliment a girl’s muscles, he’s sexist.

Raisman didn’t say where or when the airport exchange took place.

The TSA issued a statement today saying that it conducts screenings at security checkpoints for travelers departing from U.S. or U.S territory airports, and that it appears Raisman was traveling from a foreign airport.

It says it has reached out to her via Twitter for more details and that if the situation took place at one of its checkpoints it will “look into this further.”