Knee to the female crotch
[https://www.reddit.com/r/ItHurtsGirlsToo/comments/1svvu86/illegal\_knee/](https://www.reddit.com/r/ItHurtsGirlsToo/comments/1svvu86/illegal_knee/)
The caption even says bone to bone contact. She has nothing but solid bone there, unlike men who has very soft, completely unshielded, external organs.
If the man and woman's positions were reversed, we'd all know how it would end. Not a slow reaction, bending back, then gets on the floor. Oh no, it would be an immediate drop to the floor!