I set up an additional profile (the ability to do this is buried in "My Account") which lets you create a separate rating system for recommendations. Then I give five stars to movies with BB scenes I like, so it starts to recommend all the movies they have which are those tough girls kicking balls type genre.

If you didn't already know, you can find if there's any groin attacks in a movie on IMDB by looking at plot keywords. If you click on the type of groin attack you want, it will list all the movies with that keyword.