Follow up...

First things first...they say you learn something new everyday. Well, today I learned 2 things. 1) How to change a headlight in a Honda and 2) It's probably worth it to pay someone to change your headlight in a Honda.

Moving on...

Yesterday I wrote about not taking everything you hear as a strict law that can be applied to any situation, and gave an example of the exercise science student who was told to "never" let her knee move beyond her toes. Well I got this response from a friend of mine from grad school, Sharon, who is now teaches Kinesiology at Ithaca. It's a very well thought-out response, and will seem even more-so if you try to read it in a Briti...oops I mean Aussie accent...

"Hi Jon

I thought it was about time I read your blog, and I'm glad I did. I'd like to address your 'knees over toes' point. I am one of the several who teaches the knees behind toes general rule when performing squats / lunges, etc. I do this simply as it's a good rule of thumb when teaching technique to the general population. I'm not certain of the precise mechanism in play, but I teach this way as keeping end knee flexion ROM <90deg> both a) maintains the mechanical advantage of the patella and b) keeps the knee flexors/extensors at an ideal length for force generation (the latter of these also contributes to knee stability, crucial when overcoming heavy loads). I teach my students to supervise their clients in this way as it minimizes potential for joint injury in those who don't understand the principles behind the rules. Once you begin to deal with a 'non-general' population, the rules obviously change to suit different goals.

I appreciate that you were asking your client to adopt the knees over toes posture only as a one-off, but I wanted to clarify why I teach the posture I teach :)"

I only included the last part, the Mike Boyle bit, to show how oblivious I am with jokes. But a couple more thoughts on the subject...

She makes valid points about maintaining a mechanical advantage and an ideal length-tension relationship with knee extensors/knee flexors (knee extensors working while flexors stabilizing). This is important and can seem crucial if only looking at the knee joint. But as I alluded to (sort of) in the squatting example, we sometimes have to choose between the lesser of 2 (or 3) evils; pushing the knee out over the toes vs. increasing shear stress to the lumbar spine. The fact is, if the athlete doesn't have the ability to stabilize their knee in multiple planes, they really have no business doing any lifting under heavy load. This is one of the reasons we need sufficient dorsiflexion in the ankles, so the knee can be more stable and not try to make up for the lack of range elsewhere. Gray Cook points out that you always work, in order, mobility, then stability, and finally strength.

And not all situations are created equal...In lifting, there are times when you don't want your knee to move over your toes. This doesn't mean it should never happen. Think about an athletic position; If I put my athletes in an ideal position for multi-directional movement, their knees better be over their toes.

This hips can't move back without the knees and shoulders moving forward to keep the center of mass in a good position to move

Why??

Well, what's the first thing we tell athletes to do to get in an athletic stance? "Get low and push your hips back." Well this triggers a chain reaction that requires the knees to move forward and shoulders to move over the feet as well (We'd never squat in the position-but it does look somewhat like an RDL). This position loads the ankles to allow for more explosive plantarflexion on take off in any direction (so long as our backs stay neutral-rounded back=unloaded peroneals and weaker starting speed). As always, I credit Lee Taft with providing me with this info.

So I'm done rambling now, but I appreciate the response from Sharon, and encourage anyone else to jump in, even if it's to suggest I write about something else since this is so boring.

Jon