KPj and Peter--I'd like to see a debate on the single-leg first vs. full-squat first issue.
As mentioned in my post, I'll use a "low" box step up with pretty much anyone - so the double leg before single leg isn't 100% accurate. Basically, if they can do it i'll use it, if they can't I won't. (i agree if someone can already lunge, they can squat, btw)
That aside, I guess there's a few reasons
-Like step ups/stairs, everyone already squats, and most do so badly. Everyone already deadlifts, and most do so badly. I'm taking something they already do, and improving how they do it.
-I'm a big believer in having "the ability" to nail a below parallel squat. This is probably a post in itself. However, the squat is probably the most fundamental of all movements. I won't necessarily TRAIN the squat, but i'll always train the "ability" to squat. I often tell people this, since i'm known in my gym for my love affair with bilateral squats and DL's - I actually have a regular client who doesn't "train" either, but she can "do" both. In order to have the ability to do them, we had to train them, but as soon as she had the ability, we went all single leg.
I think the biggest issue is "what's the best way to get people good on one leg?". Do we try and start on one leg, or do you start on 2? I start on 2.
First, though, I find it interesting on where to "start" with single leg. I've changed opinion various times. Mike Robertson says Step ups. Mike Boyle says split squats. How can you question either? I've found that you can get people to do step ups straight away, so it seems natural to start here. At the very least, they're there to create a training effect.
However, when it comes to progressing to lunge variations, I find most people struggle most with the eccentric phase. Getting back up is essentially very similar to a step up. Getting down is significantly different, and I find that step ups don't prepare you very well for this, since there's pretty much no eccentric phase, which is why almost anyone can do them. Therefore, whilst i tend use some kind of step up from the start, I don't consider them a good progression to lunges and other single leg movements.
I've also just had lots of people who can step up pretty well, yet struggle like hell to b/w lunge. However, i've not had anyone that couldn't do 15-20 good form, below parallel b/w squats, who I couldn't coach into a decent, pain free lunge.
In that sense, I just believe that if you don't have the strength to squat on 2 legs, then you certainly don't have the strength to lunge on 1 leg. I think this is analagous to double leg jumps vs single leg jumps - would you have some one do single leg jumps before double leg? I reckon it could be a disaster....
So, with my own experience so far (note - not much), i've swayed towards the Boyle way of thinking - Develop strength on 2 legs, then move to 1, and start with split squats. Above all else, I find it makes life more "simple".
I don't really think much/any of this will be a counter point as such, probably just 2 different roads to the same destination.