I was in the eccentric phase of a set of my own innovated exercise, the single leg stiff leg deadlift, when it hit me! No, not the muscle pain! But the realization of a possible explanation of a question that has gnawed at me for a nearly a decade!
You see in the few years following my initial release of this exercise (first in 1998 in my Strength Specialization DVD series, then on t-mag articles, and the video 'Ian King's Killer Leg Exercises sold by t-mag, and in the Get Buffed series and in the How to Teach Series in 2000 etc.), I could not fully understand this:
Where did the 'variation' on my innovation - where you allow the non-working leg to drift up the back like a counter balance - come from? Why?
My initial conclusion and I believe there still is merit in this possibility - that it was a simple misinterpretation. Keeping in mind that many of the photo shoots done for my articles and book published by other publishers were shot in my absence. So this is a real possibility - the model misunderstood it; the photographer got it wrong, or the editor or the publisher....
But suddenly I had an additional reason!!! And of all places to come to me was while I was at the business end of a set of the very exercise!
Now when I first noticed the 'variation' it caused me to scratch my head. And to this day, nearly a decade later, I am still scratching my head. Why? Are they serious?
I have gone through all the possible reasons:
1. Firstly, as I said above there is the real chance of simple misinterpretation.
2. Secondly, some gate-keeper of the truth somewhere felt he was missing out on the kudos so felt the need to tweak the original version to get a warm feeling of being an innovator.
3. Thirdly, you get the approach 'Well if I reverse it up I can pass it off as mine'. (Like my innovation the Co-contraction partial range - where another has chosen to promote the movement in the absence of credit to its origin, reversed the title to Partial co-contraction Lunge, and reversed the movement order - more on that another day...)
But that was all the answers I had found, and the question still confounded me - not only where did it come from but why would you do it?
Here's my interpretation of what's going on when you do this 'variation'. I have never written about this before so I have kept my silence all these years.
And no, I don't have any science to 'back me up'. I'm just a simple coach. A coach who simply developed the movement in the first place, an exercise used throughout the world today, for the most part disconnected from it's origin because so many want to be 'significant (like another exercise I innovated, the King Deadlift, where I finally said 'Right, I am going to put my name on this one because all the others I have realised by have bastardized and claimed by various self-appointed gate-keepers of the truth.' I was reading a document the other day that is about 20+ pages long and it was a 100% copy of KSI propriety information - with the exception that the word 'King' was removed from this exercise description and replaced with 'the words Single leg'....more on THAT another day.
Anyway, I digress.
From my simple coach mind, using the same thought processes based on extensive practical application, I raise this points about the 'variation' where you allow the non-working leg to raise up behind the body as you lower towards the ground:
a. it takes the stretch off the target hamstring, reducing the primary benefit of doing this movement
b. It becomes an exercise of counter-balancing body parts (back leg against trunk) and therefore becomes more of a mechanical balancing act than an isolated exercise full range on the target hamstring and poster chain.
c. if you need more load, as some 'experts' claim you need as justification for the movement - go an do more load friendly exercise - like the single leg hip/thigh extension on a roman chair etc.
So I finally have another explanation, and it hit me as I was executing the movement - no better place for real world solutions to appear - THEY CAN'T TOUCH THEIR TOES.
I know what you might be asking - what do I mean? So let me explain.
If you cannot touch your toes with your legs straight, seated on the ground or standing, then you probably won't have much success in executing this movement full range with the load of your upper body, or external load in the form of DBs. Even though the original movement allowed and expected a minor knee bent, the additional range this allows relative to a fully straight leg is probably negated by the load.
So quite simply if you can't touch your toes with legs straight, you probably will look for any way to do this movement OTHER than the way I introduced it originally - with working leg knee only slightly bent, and the non-working leg kept still just off the ground, parallel to the working leg but not touching it or the ground.
Is this theory accurate? Can't say for sure yet. I am happy to test it over time. But I am excited and relieved to have added another possible explanation to a question that has been bugging me since the first person sought to 're-invent' this wheel. And I have often wondered....why haven't I seen more of those who teach my exercise as the 'expert' performing it in the ordinal form, themselves.....