Several causes, and the perspective of muscle lock
After care, tightness eases and the body feels lighter. Moving can also make things easier.
On the other hand, a particular stiffness remains despite thorough care. Even if moving becomes easier for a while, the same difficulty comes back. Athletes and care practitioners sometimes face cases like these.
In Zeroka Seitai, we separate what has changed from what remains without fully changing, and consider what is involved in the stiffness that remains.
Separating what usual care changes from what remains
Even when care brings change, the movement the athlete is seeking may not yet have changed enough.
For example, the body feels lighter overall, yet changing direction one way is still difficult. Tightness has eased, yet a particular muscle stays stiff and is hard to engage or relax.
In such cases, we confirm the change that has been gained and then identify the remaining issue in concrete terms.
Scroll sideways to read the full table.
| What we check after care | What we consider next |
|---|---|
| Tightness and heaviness have eased, and the necessary movement is possible | Make use of the changes gained in later training and care. |
| Things are easier overall, but a particular stiffness or difficulty moving remains | Check whether another factor is involved in what remains. |
| Things change at the time, but the same movement becomes difficult again | Review the factors not yet fully addressed, and changes caused by later load. |
When change is insufficient, rather than simply repeating the same response, we ask: might another factor need checking? This is Zeroka Seitai’s starting point.
Bringing the perspective of muscle lock to the stiffness that remains
The interpretation we have particularly emphasised is “muscle lock”.
In Zeroka Seitai, we consider that when a muscle tries to contract but cannot contract normally, this can trigger a lasting state in which the muscle does not readily relax. We call this phenomenon or state “muscle lock” and treat it as one possible factor behind stiffness. How it arises is explained in more detail in R-1.
We consider that even if responding to other factors makes things easier, difficulty moving in that part may remain if muscle lock remains.
A figure showing Zeroka Seitai’s interpretation | Looking for remaining factors from the changes brought by usual care
How does it respond when engaged and relaxed?
We do not decide that “it hasn’t changed with care, so it must be muscle lock”. We compare the quality and distribution of stiffness, the actual movement and the response after our work.
“Muscle lock” is also a descriptive term used in Zeroka Seitai. What it shares with, and how it differs from, existing knowledge and methods is considered by comparing specific content.
Considering the background to muscle stiffness from three perspectives
In Zeroka Seitai, we mainly understand muscle stiffness from the following perspectives.
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| Perspective | Zeroka Seitai’s interpretation | What we check |
|---|---|---|
| Factors related to circulation and clearance | The possibility that a state we describe as “waste-product build-up” is involved in the stiffness | How stiffness and movement respond to the athlete’s usual recovery care or similar care |
| Factors related to supply and energy | The possibility that factors such as insufficient ATP are preventing the muscle from softening fully | How the target muscle changes when we work on areas we consider involved in supply |
| Muscle lock | The possibility that the muscle does not relax by itself and stiffness remains | How the muscle and movement change when we respond to lock |
This is a framework Zeroka Seitai uses to think about the background to stiffness. It is not a medical classification that divides every cause of muscle stiffness into these three. We do not measure or establish ATP levels, the build-up of substances or the state of blood flow from the feel under our hands alone. “Waste products” is an expression used in this interpretation; it is not the result of identifying a specific substance, and we do not use it to mean lactate or inflammatory substances.
We also consider not only cases where each factor is involved on its own but also cases where several factors overlap.
“Clearance” here is our working term for the carrying away of what builds up in the muscle. It is a working interpretation, not a diagnosis, and it does not identify a specific substance or a measured process.
Placing the response to muscle lock within the whole picture
Focusing on muscle lock does not mean replacing the care the athlete has received so far.
If responses aimed at circulation or similar factors bring some change, we build on that change. If we then interpret that lock remains, we add a response to lock.
Conversely, if the muscle does not soften sufficiently after we respond to lock, we check other factors, such as those related to supply.
The next figure shows the overall approach when we interpret that several factors overlap. Even after a response to one factor brings change, we check the stiffness and difficulty moving that remain and plan the next response. The process of moving back and forth between palpation and interpretation is explained in A-2, and the review when stiffness returns in B-1.
When several factors overlap in stiffness
An abstract schematic of Zeroka Seitai’s interpretation
- Respond to one factor
- Some stiffness or difficulty moving still remains
- Re-plan the area, method and sequence
- Check with the muscles and movement
The overlapping colours are a way of thinking about several factors. They do not show actual muscle tissue, or the amount or proportion of each factor. The order of responses is not fixed.
Figure R-4-2 | An abstract schematic showing Zeroka Seitai’s interpretation. In the Japanese edition this figure is an illustration; this English version presents the same elements as an HTML diagram. The overlapping colours are a way of representing several factors for consideration; they do not show actual muscle tissue, or the amount or proportion of any factor. The order of responses is not fixed; we choose it according to the quality of stiffness and the response.
What matters is not to add more methods across the board, but to identify what is preventing change in the current condition.
Our experience in practice, and what we take from it
We have seen cases where a muscle that was slow to change with one response softened more readily when we added work on another area. However, we keep this observation separate from any causal explanation of how factors such as blood supply, ATP or clearance were involved. The specific sequence of responses is described in A-2.
For areas where stiffness has persisted for a long time, we think that poor gliding between fascial layers is also involved. Rather than starting by forcing them apart, our approach is to respond to the problem we interpret as related to circulation, and to check whether the condition changes without strong external stimulation. The explanation that “as circulation returns, the spaces between fascial layers become moister and glide more easily” is our hypothesis; it has not been established by directly measuring fascial adhesion, water content or blood flow.
Confirming what usual care changes, and looking for other cues in the stiffness that remains. We consider responding to muscle lock together with putting in place the conditions under which the muscle can soften.