yeah,nowadays Belly dance, shawl-dance r quite popular in russia, so some women learn them. Actually, this sort of dancing cant keep women fit:))) women who r fond of it have bellies, otherwise no use to learn it (skiny women can hardly do it):)))
My wife used to go to belly dancing classes, that's how I know, she's not skinny but she doesn't have a belly either, she never deterred me from attending just so I could have a laugh but I always found the bar of the Irish Pub to be more appealing :)
how can she make her belly move then if she has no belly at all? :)) or she just moves her hips? then its not a belly dance, at least not the dance it should be. i used to know many girls who did it, and they had bellies, but were not plump (maybe just a little):)
anyway if yr wife did it rather successfully without belly,then she must be an expert in it:) (actually i can hardly imagine a woman of 40-50 y.o. who has no small belly...)