The article on Whole Training has generated several comments and some interesting back-and-forth with the authors (Dr. Bain and Dr. McGown) and readers.
Below is some text from an email between Dr. Bain and a commenter. The text was originally put up as a comment in the Whole Training post, but we thought that it (and the articles to which it refers) merited its own post.
Before I respond to your blog post I want to frame it in the same way that I provide feedback to our players when we are correcting them in practice; i.e. “This is information, not criticism”. Hopefully, you will receive what I am about to write in that spirit. Knowing Carl as I do, I am sure that was his intent as well when he responded.
With that brief preamble, your response to the “whole training” article that Carl and I wrote, and the comments/questions you posed, underscore the conundrum that widely held beliefs on motor skill development and strength training, which are cited as unequivocal “truths”, have little or no factual basis or support in the scientific literature. Even so, such beliefs are held up as fact and are deeply embedded in coaching culture and training methods at all levels of the game (and unfortunately, in most other ball sports as well). That this is so is exemplified by the editors of “Coaching Volleyball”, who were happy to publish our article as an important contribution to the “debate”. As a scientist, I find it rather ironic that in the whole vs. part debate, opinions seem to carry as much weight as fact.
In any event, there are many excellent articles that serve to address the issues you raise in your post and I have attached three of them to this email.
With respect to your beliefs about strength training, please see the review article by Witten’s group and that of Jensen. Winett’s review clearly debunks what we “know” about strength training, substantiating that “less is more” (or is as effective as more) and the same training influences that optimize motor skill learning (random practice, contextual interference, etc.) have the same potency in strength training. This is an extremely important idea in physiology and has influenced my own work in musculoskeletal adaptation where we have shown that the skeleton essentially ignores stimuli that are not novel and responds more profoundly to exercise when rest periods are inserted at regular intervals. The molecular and cellular mechanisms for this have been revealed but go beyond the scope of this response.
The paper by Jensen essentially explains why motor learning of a specific skill is inseparable from the force variables that control its execution. The Adkins’ paper (Jeffrey Kleim’s lab) also has much to say on this topic but the important point is, “corticospinal system is not only plastic but that the nature and locus of this plasticity is dictated by the speci?cs of the motor experience. Skill training induces synaptogenesis, synaptic potentiation, and reorganization of movement representations within motor cortex. Endurance training induces angiogenesis in motor cortex, but it does not alter motor map organization or synapse number. Strength training alters spinal motoneuron excitability and induces synaptogenesis within spinal cord, but it does not alter motor map organization. All three training experiences induce changes in spinal re?exes that are dependent on the speci?c behavioral demands of the task.” (Please note how important specificity is to all parameters of the motor experience ~ this is crucial)
It follows from the above that the structural adaptations are tightly coupled to the movement patterns and force variables engendered by neuromuscular activity. Again, the scientific literature is full of evidence demonstrating this relation but if we simply imagine how a child (or a young animal) learns and adapts to its surroundings it is immediately obvious why this must be so. Ecologically, we are reared in settings boundlessly rich in visuomotor content and environmental variability. Said another way, our neuromuscular systems are genetically tuned to adapt to random stimuli not “block training”.
When these factors are considered In the context of the volleyball spike (which you posed as an example), the force variables associated with the dynamics of skill execution are inseparable. As the execution of this skill in competition is random (i.e. no two spikes are identical), the force variables required to execute the skill can ONLY be optimized by random practice, which, over time, will produce the maximal amount of optimal solutions for expert task execution. Again, look at the work of Jensen and Kleim (and others), and you will realize why there is essentially no transfer of block training to the acquisition of skilled performance. It simply doesn’t train the right neuronal systems. This is also why that unless the 200 lb male and the 90 lb female are both expert volleyball players, there is no way to predict which one will have a more powerful spike. Similarly, the tennis serving example you pose is a “well known fact” but it is simply not true. ALL of the research has demonstrated that skills are specific to the task and while the tennis player might be a good server there is no scientific rationale to predict that this will be so. I have to admit at this juncture that I have erroneously applied some of these well known “facts” myself. Best example is that when I first started coaching volleyball I tried to recruit the tall basketball players to play middle because I just “knew” they would be awesome slide hitters. The only thing I learned was that they weren’t and all it did was piss off the basketball coach. Give me a 5’7″ kid that has been in our program since Jr. High and we’ll run circles around 6 foot basketball players that don’t have volleyball skill training.
See Witten to clarify your statement about training volume and its influence on muscle growth. Current research is revealing that this is simply not the case.
Yes, you can achieve a higher training volume with blocked training. Wonderful, but my question for you then is this; “If we know conclusively that block training doesn’t create motor maps in the brain that are representative of movements we need in competition; and we know conclusively that force variables are tightly coupled to execution of the specific movements; and we know conclusively that block training does not lead to skill transfer (i.e. motor learning); why would we train that way?” Further, if you look at the references in our article about random training you will find that if you control for the amount of time practiced, your assumption that 1500 blocked spikes per week is superior to 300 random is false when it comes to measure of skills in game situations.
To your question on the principles of diminishing returns ~ emphasizing again that the adaptation is specific to the task ~ there is for all intents and physiological purposes no “intersection” of whole/random and part/block. It does not exist. These activities stimulate different brain pathways, optimize different neuromuscular functions, and are, at least from a motor skill perspective, completely independent . Again, if you control for amount of time practiced, random will be far superior to block for all of the reasons previously cited.
Finally, scientific research has revealed that skills AND strength are specific to the task. Serving is a great example of a closed skill that can (and is) trained in a block fashion to increase serving strength. However, in our gym, we know that eventually this skill will be executed in a random environment with environmental cues and stressors not normally present in practice. Thus, to optimize the acquisition of this skill we train it randomly and use contextual interference, which we know will optimize BOTH skill AND strength acquisition.
Joe, I hope that you will receive this information in the spirit it was intended and I encourage you to continue to ask probing questions that stimulate thought provoking discussions such as this. Carl has been instrumental in provoking my own personal pursuit of the answers to these fundamental questions and I hope that in some small way this response has been helpful in your own quest.