If you have read the Old Soviet Sports Reviews and seen any of the articles by Verkhoshansky, I think Westside is based on the concurrent methodology. Here a post by Dr. Verkhoshansky on the subject. (Sorry it is long as hell) Hope that it helps clarify some things.
" I introduced the ?conjugate-sequence system of training loads organisation? (Block ? system) for Olympic sport athletes. It?s absolutely another thing from the “conjugated periodization” of Simmons. I agree with Dan: ?Westside is not actually the “conjugated sequence system”. Westside looks to me more a concurrent method which borrows some features from other systems?.
In East Europe sport training methodology, the word ?periodisation? means the subdivision of training process in periods related to the different training?s tasks. There is also the conception of Training Periodisation of L. Matveev, that is based on his particular principle of training?s process planning, different from my conception of ?Training Programming?.
But from what is in my knowledge, I can suppose that in the West the word ?periodisation? is synonym of ?training?s planning? and the conception of Matveev?s Periodisation has named ?Linear periodisation?. My conception of ?Training Programming? is often wrongly associated with word ?programming? that is the general activity to define the training programs.
May be also the word ?conjugate? has been used in the West with another meaning.
For example, I am not sure that the Conjugate Method of Luis Simmons is the same Conjugate Method that I know.
In the article of Simmons ?The Conjugate Method? has been reported that this method was invented in 1970th by weight lifters of Dynamo Club (USSR): ?They were introduced to a system of 20-45 special exercises that were grouped into 2-4 exercises per work-out and were rotated as often as necessary to make continuous progress They soon found out that as the squat, good morning, back raise, glute/ham raise, or special pulls got stronger, so did their Olympic lifts. When asked about the system, only one lifter was satisfied with the number of special lifts; the rest wanted more to choose from. And so the conjugate system was originated.?
The Conjugate Method that I know was invented in 50th by my teacher, the famous high jumpers coach V. Djachkov. It was a brilliant idea to use the special strength exercises for improving the technique of athletes. For the first time in the Sport Training Methodology was introduced the idea that to adjust the competition exercise technique is necessary to increase the strength level expression in determinate movements.
At that time I and Djachkov elaborated together this method and I suggested him to name it ?conjugate? because the strength exercises have to be ?conjugated? with the technical issues of the athletes. After, I introduced the Principle of Dynamic Correspondence to select and elaborate adequate special strength exercises on the base of the biodynamic structure analysis of competition exercise.
Often, in USSR the Conjugate Method was used also as ?the execution of competition exercise with overload?.
So, the original idea of ?this? Conjugate Method is not simply ?the rotation? of the same group of special exercises during the preparation period, but it is the ?conjugate? use of special physical preparation exercises and technical exercises in the same training session.
In 60th, I started to use the special strength preparation exercises and technical works not in the same training session, but in different sequenced training sessions, and later, in different sequenced training stages.
When I elaborated the structure of special physical preparation in speed-strength disciplines, I understood that also special strength work consists in different types of exercises, that can be conjugated from them in sequence (can be used in different training sessions and in different training stages).
This idea was utilised in my Physical Preparation Training Methodology where I introduced:
the Conjugate-Sequence System of training loads organisation, the Principles of Concentration and of Superposition of different training loads and the Block System of training.
Therefore, now in the East Europe sport methodology there are two different models for the use of different types of loads in training process: complex-parallel and conjugate-sequence.
In the first case these loads are used together with ?continuous rotations of the same special exercises? during all preparation period.
In the second case these loads are used in the sequence, one type of loads after another, everyone concentrated in a special training stage.
If the conjugate periodisation is another name of complex-parallel model of training loads organisation and you wish know my opinion about it, I can answer very shortly.
The complex-parallel model is much more simple than the conjugate-sequence because it doesn?t need the exactly quantitative model of training load distribution during the preparation period.
It?s better use the complex-parallel model for non expert athletes who have a not stabilised technique and a low level of physical preparedness (in any case when the coach doesn?t know very well the training experience of the athletes).
The complex-parallel model can be used also for high level athletes:
in the first phase of preparation period, before they start the concentrated physical preparation work,
when they don?t need to increase radically their physical preparedness level, but they need to ?conjugate? their high level physical capacities with the technique ( it?s particularly important in some sport disciplines).
In generally, the conjugate-sequence model is much more effective that complex-parallel for high level athletes with high level of physical preparedness.
In the sport disciplines where the sport result is strictly related with the increase of the physical preparedness level these athletes need to increase further their level of physical preparedness. In this case the training programs have to be elaborated very carefully.
There are many other aspects about this issue but it need too much time to explain all the aspects involved.
I hope this post will clarify, at least, the main arguments.