The menstrual police are going to show up like storm troopers with dogs to sniff out periods.
I organize competitive sporting events and a few times men have entered as women and people get pretty upset about that. I don't think they did it to win their age group, maybe, but it, but it's probably not like that. One thing events do outside the USA is have a third category for gender that's like 'none' basically which means they don't want to compete in their gender/age category. I have not noticed that in the USA yet.
There's always cheaters though, people taking tsxis or cutting corners. Just to get a medal or recognitiom or whatever. Big races don't usually do prize money or they have pre-vetted elite champions competing for money.
Florida weighs mandating menstrual cycle details for female athletes
CLAIM: Florida Gov. Ron DeSantis is requiring all female student-athletes in the state to provide detailed information about their periods in order to compete in organized sports. AP’S ASSESSMENT: False.