To ask for some perspective please

[Elmagr10]

is it normal for someone involved in a sports club to ask young girls to share when they are on their period?

This is a hobby essentially, not an elite level at all and girls are 12 and 13 yrs old.

Could anyone hazard a guess as to why this would be considered appropriate?

I can maybe see the point if its swimming or something, maybe. But no I don't think it's appropriate to ask people to report when they're on their period, particularly young girls, it's tricky enough at that age for many to deal with periods and everything around them without having to feel like they need to share the info with some random coach