I was recently reminded of this drill as, last week, I tested my hip internal rotation and found it to be woefully lacking, compared to just twelve months ago (pulling SUMO five days a week, along with already possessing extremely overused and stiff external rotators, will certainly have this effect....) While I've been much more diligent at working on my hip extension patterning, I've admittedly fallen by the wayside when it comes to fighting against the loss of hip internal rotation (IR). As such, I began to toss this drill in at the end of my training sessions again and thought I would share it with those of you who may be interested.

Do you care about sound positioning in the bottom of your squat (this = pwnage of heavy weights, by the way), improved running mechanics, or lessened risk of back pain? Do this:

What's it for?

To improve hip IR. Specifically: a loss of hip IR caused by muscular restrictions (as opposed to passive restrictions such as labrums, minisci, bone, etc.). A couple notes

I'd recommend doing this after you've already pulverized your external rotators with a lacrosse ball or other means of soft tissue work.
Don't force range-of-motion here, just gently mobilize the knees in and out. You shouldn't feel any sensation of impingement and stop if something feels "off."
If you're a female, I wouldn't jump the gun on this one. A lot of females already tend to have a fair amount of hip internal rotation, due to their hip structure (wider hip bones and thus larger knee valgus at rest).
This can be performed before a training session (especially if you're squatting that day, as you'll notice significantly improved hip mobility as you descend into the bottom). It can also be used at the end of a lifting session or athletic event (especially if you're a baseball pitcher, or partake in a rotational sport) or training session. This will help loosen up the external rotators of the hip that tend to tighten up over time.
This drill can also be done with the feet on the floor (a valid option), but I personally prefer to have the feet on the wall as it tends to be a bit more low-back friendly.

Incorporate this into your routine for improved squatting and running mechanics.