A while back I wrote an article about the Polish and Russian perspective on knees back in the snatch and clean. The article is about how long to keep these back and if, or ever, should the lifter think about pushing the knees back forward for the double knee bend. The conclusion I came to was keep the knees back as long as possible and let the knees coming forward take care of themselves.
The reason I teach the lifts this way is because of a bad habit of my own and one that I see far too often in the CrossFit world. This specifically is true of lifters with a high potential for explosive power, yet also lack an overabundance of absolute strength. Like myself. The cue I have been using lately that has helped many lifters to stay over the bar and continue the leg drive is “heels down”. I know that sounds simple and something we have probably heard since we picked up a barbell on day one, but more often than not the reason we allow our knees to come under the bar and don’t stay over the bar long enough is because when the bar passes our knees we immediately start to shift our weight to the front of our feet and our knees under the bar thus forcing our shoulders behind the bar too early. This leaves us in a power position where our shoulders are behind the bar and hips, and our bodyweight is up on the balls of our feet. The reaction to this position is for that the hips move horizontally into the bar and the bar to moves out away from the lifter.
Just like I posted last week, The power position, when optimally performed, leaves the lifter with the bar at the hips, shoulders even with the barbell, and the feet flat. This position, in which most of our power can be transferred into the bar, cannot be achieved if we shift our knees under too early and allow our heels to come off the ground. Remember, when driving the bar off the floor to keep the heels down as long as possible and continue to sustain the leg drive for as long as your body will allow. A long sustained leg drive will increase power output into the second pull and as a result increase bar height.
My inclination is to always, especially under heavy load, shift my knees under early, which shifts the weight to the front of my feet and my shoulders behind the bar too fast. Everyone knows what this position looks like (see below). The key to preventing it is a sustained leg drive. Drive those heels to the floor and keep driving those heels through the floor until it is no longer possible for you to do so.
One of the key exercises that I use and that my coach uses to create this habit is called a clean or snatch pull to explode. See the link below for a good demo on how to pull that off.