Isolated deceleration training is not a good use of time
I often think of the benefit of deceleration training, which, if I am being honest, I have always struggled to see the value. Part of the issue is that I struggle to fit in. I am not even sure I value the concept of isolated deceleration training. This is my opinion, but I must say every time we bring this up in staff meetings, I wonder about the value. I do not think it is a stretch to say that when it comes to isolated deceleration work, it is very low on the priority list. We know where the conversation stems from; deceleration is always connected to athletes who are at increased risk for ACL tears, such as basketball, soccer, or positional players in football. Deceleration is presented as the blind spot we are not addressing and leading to unnecessary injury. If we were to include it in our training, would we simultaneously reduce risk and improve performance for our athletes?
Deceleration training is considered crucial for performance, but lacks any real substantiave evidence if it brings value.
The biggest reason why deceleration training is not valuable to me is that it is hard to quantify. We typically look at change of direction (COD) as the primary means to assess deceleration ability. But it is not a perfect test to accurately depict deceleration ability. To elucidate my point, the easiest way to define deceleration is to think of it as the opposite of acceleration, which is a change of velocity over time. We typically examine acceleration as it transitions from zero velocity to maximum velocity. So by that logic, are we to look at time from a max velocity down to zero velocity to quantify deceleration? I can easily justify including acceleration into training due to its direct application to the performance of sprinting faster to increase the speed reserve for our athletes to utilize during competition. With deceleration training, I can understand the logic, but it lacks substance in its relation to performance. When do we ever simply stop?
Does the predetermined stopping point we use in deceleration even matter in the first place? I know there are tests that we can look at, such as a fixed sprint distance followed by a fixed distance to stop, or a fixed sprint distance followed by a variable time to stop. To assess deceleration, we have to look at time and steps. We can use ground sensors to measure ground contact force with load sensors, but again, does that even matter? Does a test that looks at only stopping even actually translate to performance or potential for injury?
This is where I struggle with deceleration training. What gets measured gets managed. Most deceleration is just an eye test. Does the athlete give good effort before the deceleration, and do they stop in a good position? That is about the extent I appraise the effectiveness of deceleration. Any testing procedure is going to be questionable with validity and reliability, as all deceleration ability is contingent on the preceding acceleration. In order to truly appreciate deceleration, it can only be viewed in its relative role to COD. From my perspective, isolated deceleration training is futile unless it is at least connected in some way to a corresponding redirecting and acceleration.
COD Hardware Versus Software
Deceleration is hard for me in regard to training due to the practicality of it all. Most of the need behind deceleration appears to be interpreting in-game situations and being in a good position to make a ‘play’. A close-out in basketball appears to be more related to reading a cross-court pass than breaking down into a close-out position. We can work on all the deceleration mechanics we want, but if the athlete lacks the awareness to read and interpret in-game dynamics, deceleration ability is not the limiting factor. Fractals (simple rules repeated) will indicate that we have at least the foundation of biomechanics during deceleration, which is traditionally absorption through simultaneously bending of the ankle, knee, and hip to stop. That triple-flexed position is preparatory for an acceleration in the opposite direction. A good decelerative performance is based on the number of steps or distance traveled to get to that triple-flexed position. In my opinion, we get enough of that during extensive and intensive plyometrics and direct strength work. If we are trying to isolate a particular aspect, we should at least have a focus on developing strength (eccentric, isometric, and concentric), power, or speed. Those are more readily developed with direct plyometric or strength exercises.
But with that being said, COD comes down to physiological/biomechanical and cognitive/perceptual criteria. Do we have the foundation of hardware to tolerate the stress of COD as well as optimize with efficiency to change direction effectively? The foundational biomechanics of being able to synchronously absorb in a triple-flexed position with the passive connective tissues, along with the physiology to react towards a triple-extended position with the active contractile tissue. It is fractal. If we do not have individual segments, we will not have the aggregate of those segments. If we can flex and absorb with our joints during deceleration, we will not have that during COD. We do need to evaluate if we un fact do have the machinery to take that stored energy in our passive tissue and utilize that energy to a net positive reaction, we will not have that during COD. We need to have foundational loading and propulsion ability to have in-game COD ability. In a sense, we can look at deceleration as only as good as the subsequent action created from that deceleration. That is the essence of having foundational hardware.
When you think of hardware, you’ve got to go through all the biomotor abilities: strength, speed, power, eccentric strength, and reactive strength. That is combined with the biomechanic factors: movement capability/variability and symmetry. You have to think of both biomotor and biomechanical as interdependent and not independent of each other. One attribute is not more important than the other, unless they are deficient relative to the others. That deficiency becomes a liability in COD ability due to the increasing demand on other aspects. For example, eccentric strength limitation increases demand on mobility due to longer absorption periods. Low reactive strength increases concentric strength/power from a lack of passive energy transfer from the SSC. This is why I value plyometric exercises such as jumps, hops, and bounds in all three planes of motion. It’s also why I value strength exercises in both bilateral, split, and single-leg stance, also done in all three planes of motion.
We are going to go over how to assess this on a force plate for Part II, but you can see how an isolated sprint-deceleration assessment might limit being able to find a limiting factor. The ability to be reliable on a force plate to appraise peak and average levels during a countermovement jump or eccentric utilization ratio assessment makes a sprint-deceleration test inadequate. We can, in turn, engineer the underlying hardware with prescribed plyometric and strength work to enhance the decelerative capacity to translate into a corresponding acceleration in another direction.
In terms of software, we are looking at familiarity and the neuromuscular apparatus to translate into effective COD. Perception, decision making, anticipation, movement strategy, and finally experience are critical to applying deceleration in dynamic open environments. We know that the speed and the randomness expose the athlete’s decelerative capacity. The faster they are going and the less they are aware of what will happen, will increased the demand on the COD. Bad deceleration is only bad when there is a bad corresponding action, such as accelerating in another direction.
We have things like motor learning, which is learning how to locomote in a three-dimensional world. Neo-Developmental patterns such as transitioning from a supine, to rolling, to prone, to a press up, to a quadruped, to a crawl, to a kneeling/half kneeling, to a squat, and finally to an upright bipedal homosapien are the foundation of our software. We spend time in these steps to develop not only vestibular, nervous, and motor systems, but also our skeletal, muscular, and neuromuscular systems. Our motor learning on a surface level appears to only be what is happening in the nervous system, but that is not the whole truth. We are making motor patterns more permanent by establishing the bodily structures of the body to propagate those patterns. Again, software and hardware are interdependent.
Now we are upright and we start to play sports. Bernstein’s Law says that ‘there are new patterns that are the same regardless of repetition of that pattern’. Obviously, this is true, but that being true does not diminish the value of rehearsal and repetition. We will not be able to predict what will happen in open environments such game or an open drill, we know this. The lack of predictability creates a more direct need to rehearse patterns of COD, whether it is a power cut where we achieve a zero velocity or a speed cut where we are trying to limit reduction in velocity with a change of direction. Because the more we rehearse something, the familiar it becomes and the greater the bandwidth to handle dynamic situations. Entropy is that all systems are moving toward a gradual state of chaos. All rehearsals do is limit entropy to reduce the rate of chaos. You do not combat chaos with chaos; you limit it with deliberate practice. In open environments, you want your default to be exceptional.
Much like hardware, software is also fractal. Think of the Principle of Progression, where we take something from slow to fast, high constraint to low constraint, closed to open, or complicated to complex to chaotic. All of those are establishing: can an athlete perform a pattern in its most distilled version before we integrate it into a raw expression of movement? We can place value on our Progression based on its integration of chaotic environments. We developed the underlying software to prepare the athlete for performance in unpredictable environments. You should appraise time spent based on its correspondence to undepictable. Is there a default good when we do not have control over what will happen? Your prescribed progression should constantly move towards its application to chaos.
What am I trying to say with Part I?
If you are looking for simple, distilled-down answers, I am sorry. I believe in earning it with everything you do.
But for the sake of if you truly know what you are talking about, you should be able to explain it simply.
- Isolated Deceleration Training is not a good use of time:
- Difficult to assess
- Not attainable and does not adequately stress with creation of adaptation
- Does not correspond to real-world scenarios
- Integrated Deceleration with a Corresponding Acceleration is a better use of time:
- Deceleration ability is based on an acceleration in another direction
- We never simply stop; we always have layers of movement
- Fractals within both COD Hardware and Software determine the rate of and quantity of progression
Part II will break down how to determine where we need to focus. But for now, if you are doing direct deceleration drills, I want to ask yourself: are those drills translating to unpredictable environments? I can empathize with the time spent teaching and drilling deceleration mechanics during training sessions; it just feels right. But this is my blog and my opinion, so take what I am saying with a grain of salt. You don’t have to like it, you just need to think about it.
But, and this is important, when you go to open drills, practice, or games, does your training transfer? Non-contact injuries are often a token issue with deceleration. All injuries are broken down to the equation of demand being greater than capacity. There is a reaction to having a string of injuries that you felt could have been avoided. Developing the ‘motor’ is easy; the ‘brakes’ are another story. We create these narratives in our mind as coaches that we have blind spots. When we have a myopic focus on something, yes, we will have blind spots. But I do not think that is the case for most S&C. We lack perspective, but that is not avoidance.
I think the issue is not looking at deceleration and its role in injury prevention and performance objectively. We see deceleration all the time with landing mechanics when we jump, body positions when we change direction, or eccentrically load during a strength exercise. Your intuition is better than you think; if they look bad when they are in any of those ‘moments’, it will not translate into a positive outcome. Landing improperly, out of position during a change of direction, or poor control/bad position/limited ROM during the eccentric phase of exercise is either a hardware, software, or combined problem. Which we know how to fix. The trick is progressing that into faster and more unpredictable environments.