Start talking about special strength or specific strength and one of the first things that often comes up is Yuri Verkhoshansky and the principle of dynamic correspondence. In our latest video lesson, I sat down with German national discus coach René Sack to discuss his framework for specific strength and how he applies it to discus throwers. What stood out to me the most is how big of a gap there is between the theory of special strength and how it is put into practice by top coaches. Dynamic correspondence might look good on paper, but top coaches like René are finding different ways to make specific strength effective in training.
Defining dynamic correspondence
If you read Supertraining or Special Strength Training Manual for Coaches, the concept of dynamic correspondence is front and center. It is the primary means by which Verkhoshansky recommends selection special strength or specific strength exercises. According to him, five factors need to be considered in exercise selection:
- The muscle groups involved in the exercise.
- Amplitude (i.e. range of motion) and direction of movement.
- Accentuated part of the movement’s amplitude.
- Magnitude of force-effort and time of its application.
- Regime of muscular contraction.
If you are a coach, name dropping dynamic correspondence makes it seem like you know what you are doing. It sounds sciencey, efficient, and precise. But the devil is in the details. How is a coach on the field supposed to convert the theory into practice?
Without a doubt all of the factors the Verkhoshansky highlights are very important. But how do you translate that into exercise selection? This approach hardly spits out a number which you can use to evaluate an exercise. Which factor is the most important? Do we need to take the exercise to the lab to measure it precisely? How much of an impact does a 5% change in range of motion impact dynamic correspondence or a half second change in time of force application? Rather than being objective and efficient, the result of a dynamic correspondence analysis is subjective and cumbersome.
In the end, dynamic correspondence oversells itself. The approach is hardly the scientific answer to exercise selection it wants to be seen as. What it really offers is a glorified checklist coaches can use to make sure key points of movement are not overlooked in exercise selection.
A simpler approach
When speaking with René about his approach, I asked him if he is doing any analysis of the exercises he is using. The German team has access to a great biomechanics team and lab in Leipzig, but when it comes to specific strength exercises they rarely bring out the sensors.
Rather than turning to science for answers about specific strength, René turns to his eyes and his athletes by focusing on what the athletes feel and how it looks. In our video, he explained: “I don’t really have a test for it. When I play around with new stuff, I ask the athletes how they think it is working for them? Do they get the rhythm and the feeling? Do they feel like they are getting stronger?”
One final element René looks at is whether the athlete actually improves as a thrower. This is a big point missing from Verkhoshansky’s work. As I but it in the video: “The most important test isn’t measuring if it the exercise angle is 34º or 35º, it is measuring if the athlete got better.” Take an excise, try it out for six weeks, and then test.
This is a simple approach, but also a much better use of a coach’s time. The goal of training is transfer, not dynamic correspondence. Dynamic correspondence can be a checklist as a starting point, but, as René demonstrates, you have to quickly move on to other feedback in order to see if it is working. We need to spend less time analyzing the exercise and more time analyzing whether it works.
The many faces of specific strength
As far as I am aware, there is also no research showing that a higher dynamic correspondence means a higher transfer of training. While it may be the case in some situations, I also often see cases where lower dynamic correspondence means higher transfer. This is one of the many things I like about René’s approach: it highlights the multiple roles specific strength training can play. Specific strength training can help prepare the athlete, help develop strength, or help develop speed.
A classic example I often discuss in seminars is the simple medicine ball twist. Among other variations, this can be done with or without a release. For hammer throwers, the movement with a release undoubtedly has higher dynamic correspondence as you can see in the video below. The angles better reflect our event, as do the amplitude and accentuated part of the movement. Doing the exercise without a release, on the other hand, means the athlete is spending half of their time decelerating and the path remains relatively flat. Is the higher dynamic correspondence exercise better? It depends. For many athletes, their issue is controlling speed and not producing speed. With such athletes I would tend to do twists without a release as these require the development of more stability by training anti-rotation which will allow them to control speed better in the full throw. These athletes find better transfer through less correspondence.
In speaking with René I think he’d agree. There is no “best” specific strength exercise. Different problems call for different tools. You have to see what the athlete needs and then figure out how specific strength exercises can help move them forward.