I am not a fan of generalization. Often times I find they come from a place of assumption instead of actual experience. I'm not here to invalidate the generalization, I'd rather erase it all together.
A female student who is a serious student of martial arts I think would more typically not fit into this generalization. You sort of walk in knowing that it will take physical and mental demands.
Well, now we're into the realm of who gets to decide what a "serious student" is. Maybe we don't want to go there.
What does it mean to "erase" a generalization, anyway? Do you wish to stop people from making an observation? What if there's truth in what they observe? If I make the generalization that sexism exists and that it has an effect on women's attitudes, why do you want to "erase" this generalization, and how do you propose to do it? Pointing out that there are exceptions to generalizations would seem a waste of time -- that is inherent in the definition of what a generalization is -- and stifling the expression of a generalization because the underlying reality is distasteful seems a case of shooting the messenger.