Close, but more in, less up.

[Lifting up to show her how to get more weight behind it. Furiosa can deaden a leg muscle with a knee thrown like that.]

Really pull your body into it. You'll never actually get the tip of your knee into someone's crotch, but you're going to be able to make them limp badly enough that they won't be able to follow you. And if you do catch them just so- well, more's the better.