There is something that all coaches need to make part of their training at any level. It is breaking tradition to manage and be comfortable with the risks of variance as found in volleyball. Two-time Olympic medal winning coach Hugh McCutcheon termed it risk management. No matter what the sport, variance is ever present, contact to contact. I would contend strongly that the training traditions of our sport teach players to err on the “negative” side of the bell curve – something I have previously covered in my article “From Positive to Perfection.” The other fact is that through variance, and the random nature of learning in any sport – the motor program is far better established. Research articles which bring more facts to override opinions found in sport include:
1. Nature Neuroscience (Feb 2014 - Vol 17 No. 2) “Motor variability is not noise, but grist for the learning mill,” by David J Herzfeld & Reza Shadmehr – Here the study demonstrates that variability in how people perform a movement can predict the rate of motor learning on an individual basis. This suggests that motor ‘noise’ is a central component of motor learning.
2. Nature Neuroscience (Feb 2014 – Vol 17 no. 2) - Temporal structure of motor variability is dynamically regulated and predicts motor learning ability” by Howard G Wu, Yohsuke R Miyamoto, Luis Nicolas Gonzalez Castro, Bence P Ölveczky & Maurice A Smith – The summary abstract states “ Individual differences in motor learning ability are widely acknowledged, yet little is known about the factors that underlie them. Here we explore whether movement-to-movement variability in motor output, a ubiquitous if often unwanted characteristic of motor performance, predicts motor learning ability. Surprisingly, we found that higher levels of task-relevant motor variability predicted faster learning both across individuals and across tasks in two different paradigms, one relying on reward-based learning to shape specific arm movement trajectories and the other relying on error-based learning to adapt movements in novel physical environments. We proceeded to show that training can reshape the temporal structure of motor variability, aligning it with the trained task to improve learning. These results provide experimental support for the importance of action exploration, a key idea from reinforcement learning theory, showing that motor variability facilitates motor learning in humans and that our nervous systems actively regulate it to improve learning.
3. The Superiority of Whole vs. Part Training by Dr. Carl McGown and Dr. Steve Bain – This article which appeared in the American Volleyball Coaches Journal in 2012 included this statement: “The neuronal explanation for these effects are perhaps best exemplified by our own observations (Bain and McGown), of inexperienced coaches training novice players where the instructor(s) become frustrated by the performance variability and lack of successful repetitions of new learners. As a consequence, these inexperienced coaches limit or abandon whole teaching methods for part, and random practice for blocked. Unfortunately, this course of action deprives the learner of the environmental variability and sensory inputs that are essential for the formation of motor maps and implicit behaviors, which are ultimately reflected in the acquisition of functional skills and expert performance.” Feel free to email me for a no-cost copy of this article if you have not seen it.
Specific to volleyball, I wanted to cover each skill from the point of view of training within the variance.
Serving – The tradition is to focus on “clearing the net.” The problem is that, even in the only closed motor program in our sport, variance means when you focus on the top of the net, half of your errors are going to zip happily into the net. I put up a string for more experienced players, and a ribbon for those less skilled, from antenna to antenna.
Spiking – When coaches say “Hit Line” you are setting them up for variance failure in that the line shot as an athlete would internalize makes for half the shots going wide. With SportCourt tiles and painters tape put about a meter inside the line, you again help a player stay aggressive with a fast arm/hard hit, while allowing for the ball to stay inside the court lines within the variance within. The shorter players may also need the same string noted above as a guidance point. Karch addressed this well in his USAV Webinar recently, found HERE.
Serve Reception - The location of the setter as the target needs changing from tradition. When you put the setter, as most do since the net is the only real reference point seen above the floor level, at the net, you are setting yourself up for a lot of overpasses. These overpassed balls may be crushed on you, at the higher levels, or even score points at the lowest level as the ball falls untouched. In any case, with the variance of the serve reception/setter target, it is important to put the target at least a meter off the net. For our USA national teams, given the speed and level of jump serves seen, the target is over a meter off. For less experienced players, whose serve reception variance levels are quite wide, I would suggest a target that is two, maybe even three meters off the net.
Setting – This oh-so-important second contact to better the ball has several areas to change/teach regarding variance – all focused on making the ball hittable. The setter who is told to “set to the antenna/pin” is thus being taught to set half their errors beyond the antenna. The problem here is that while a perfect set inside the antenna might be killed at over 50%, the ball set past the antenna drops to a kill rate well below 20% at most levels. Not to mention balls set past the antenna result in lower limb injuries at a much higher rate. The ball error too far inside is still being killed at over a 50% rate for the record. So put up a swim noodle vertically, or tape duct/painters tape on the net – a meter inside the court. This is the target all players, especially non-setters, are to aim at when setting sidelines.
Setting variance #2 to consider on the range of axis options is how far off the net a ball is set. If perfect is a meter or more back, so you can avoid the block/net/injury. Most coaches start on the net, then spend the rest of their season begging the setter to set farther back. I strongly suggest teaching hitting back row – 3 meters off, first and every practice and warm up. This way their “habit” is to vary deeper, not on or often over the net with their errors.
The final axis variance is setting height. It is better to set a ball too high, rather than too low, as higher gives time to save/adjust to a ball off of perfect. So I suggest weaving swim noodles vertically thru the net on spots where the hitters are being asked to attack, using the noodle height to show/teach the height you want the setter to put the ball to (this is for the faster sets, not a high outside). The noodles should start a bit higher than perfect, so the variance seen will still all be hittable and not too low. This vertical set of noodles may also vary along the net, not unlike a cell phone signal “bar” series, to put you and the setters/hitters on the same page of what height a ball should be set for the quicker sets.
Digging – When rockets come in from about 6 meters away, the variance even with very skilled players can be large – so our USA teams digging target is in the middle of the court – 4.5 meters off the net, 4.5m from each sideline – so that you can make a mistake of over 4 meter and….the ball is still on your side.
Blocking – As touching the net will always make any great stuff, or even subsequent amazing dig have no value, and given the distance between hitter/blocker (usually very close), I use swim noodles to kinesthetically teach sealing the gap so a ball cannot pass thru. By putting up the larger/thicker swim noodles at full length (cutting the noodle on one side to the center of the noodle, not unlike when you clean a fish) that cost about $5 or more, a player can learn to press against the “net” while penetrating over, but not look at the net (a common error in training without a ball/hitter, when they look at the net). This kinesthetic awareness is a subtle form of variance awareness.
Another area coaches need to be aware of the variance in sport is in their perception and realities of being part of a random event. Between knowledge of the impact of finite markov chains, regression to the mean and the age/experience level of athletes, things can get frustrating. Younger players have a much wider variance in play levels, but every team, and over the course of every season, teams are subjected to the fact of variance. Those of you who coach at the elementary/middle school level for any length of time can no doubt relate the fact that I have been ahead 24-0 and lost, and have won set one 25-0 then lost the second set 0-25. I have covered this in my blog “Stuff Happens” and would urge you to take the time to read and understand it, along with three other articles:
The Book – Playing the Percentages in Volleyball – a solid discussion on regression to the mean and the number of trials needed to limit the amount of impact luck has on your performance.
“Decisions, Decisions” – a Discover magazine article on Nobel laureate and founder of behavioral economics Dr. Daniel Kahneman. This TED talk by Dr. Kahneman on how our experiencing selves" and our "remembering selves" perceive happiness differently is related to this blog, and also worth the viewing and can be seen.
So I hope that this blog, and any other comments below suggested helps you teach more effectively, and thanks for your help in growing the game together…