Yagami Ryu shibari is an active style, where both participants are engaged and present throughout the session.
Let's clarify the meaning and context of terms used in this training, as we did with intention.
Flexibility is a joint's ability to move through its complete range.
Mobility is our ability to actively control that joint movement, typically through adjacent muscle use.
Mobility can be improved with specific exercises.
Elasticity is the ability of tissues, especially muscles, tendons, and ligaments, to stretch and return to their original form. This ensures tissues can withstand forces and tension without damage.
Elasticity is a natural tissue property that doesn't improve easily, though proper conditioning helps maintain it.
In practice, we aim to stabilize the joints involved in the structure we're building to achieve optimal force distribution.
For this, we must observe the tied person's mobility and adapt forms and structures to their capacity.
This will always result in less "showy" or extreme forms than if we were to rely on flexibility alone, but they are much safer and more efficient.
Therefore, using a person's full flexibility to build a restraint is not only ineffective, it's dangerous.
Muscle Activation | Haru Chikara (張る力)
Activation can be conscious, like raising a hand to wave at someone, or automated, like blinking. In both cases, muscle activation is required to perform the movement.
For sekibaku practice, both participants need to maintain a degree of muscle activation. This style seeks erotic satisfaction, so everything we do is directed toward this end.
Specifically, muscle activation facilitates the reception and transmission of stimuli, and therefore, erotic stimulation.
Muscle activation is also key to building anatomically sound restraint, allowing for safer and more efficient restrictions.
Muscles are responsible for executing body movement through contraction and stretching. While there are different types, this class format doesn't allow us to go into such detail, though we will explain some of them.
From a Biomechanical Perspective
From a neuromuscular and physiological standpoint, muscle activation is the process that optimizes muscles for a specific action. This process involves:
- Motor unit recruitment: improving communication between the nervous system and muscles.
- Enhanced coordination: synchronized activation of muscle fibers for more efficient contractions.
- Increased motor neuron sensitivity: allowing for a faster and more effective response.
- Greater muscle tension: preparing muscle fibers to handle higher loads.
- Improved joint stability: reinforcing the joints involved in movement.
- Optimized performance and technique: enabling more efficient execution of movements.
From this perspective, it's important to understand that our body is designed to move following patterns it considers most efficient and safe. We've evolved through movement, such that our muscles have specialized to perform certain movements and actions.
However, our lifestyle often differs significantly from this optimal movement pattern, and we frequently develop postural habits; this means that when we ask the body to move, our brain often defaults to using familiar but improper patterns rather than optimal ones.
For example, if we typically bend our back when picking something up from the floor or tying our shoes, we're likely to do the same when lifting weight without thinking, such as during a suspension.
This means the lumbar region of our spine bears the weight instead of the glutes, which are actually designed for this task.
These are what we call compensations, defined as using a muscle or structure not designed for a particular function instead of the one that is. Compensations are very dangerous and must be monitored and corrected in both the person tying and being tied.
When constructing different positions, it's important to understand how they work biomechanically to ensure that the correct muscles and structures are supporting weights and forces, and that their distribution is as optimal as possible.
Although we won't discuss ligaments in this class, we must note that compensations often strain them significantly, and these structures don't recover easily.
We're not saying you shouldn't move through all possible ranges. On the contrary, experiencing different movement patterns is beneficial.
However, when adopting a position where weights will be supported and various forces applied, the closer we stay to optimal postures and patterns, the better our body will distribute weights and forces, reducing injury risk.
Regarding musculature, we need to understand when a muscle is active versus inactive, and remember that our body is designed to support weight with active muscles and stable joints.
In our daily lives, the body's stabilizing muscles are responsible for protecting and providing stability to joints; we must remember this in practice when constructing positions, either by directly activating them during the session and/or reinforcing them with ropes.
In shibari, tension is key - tension in the rope and tension in the body. A rope without tension doesn't transmit, but neither does an inactive, tensionless muscle.
Generally, an active muscle is firm, while an inactive one is soft.
While this is easier to see during muscle contraction, this activation is also important during extension. This is because, generally, movement occurs through the joint action of agonist and antagonist muscles for that movement.
Though complex, we can summarize it thus: agonist muscles are those that contract when innervated to execute a movement; for example, when lifting the leg to walk, the quadriceps act as agonists by contracting to raise the femur.
Meanwhile, antagonists, when innervated, stretch to facilitate and stabilize the movement; in the previous example, the glutes and hamstrings at the back of the leg would be acting as movement antagonists.
During a shibari session, we must elicit this activation in the tied person, as the person tying has access to resources - we cannot expect them to do it consciously.
Furthermore, if we're tying with someone who tends to make movement compensations in their daily life, these will likely translate to practice, and their body won't automatically activate the necessary musculature.
For this, we can use the skin as a communication medium by creating gentle stimulation through caresses, light taps, or small pinches, always remembering that if pain occurs, the brain will resolve to deactivate the musculature as protection.
This activation is agonistic to movement, meaning the muscle we're stimulating prepares for contraction, causing the antagonists to prepare for extension.
This is important because if we do it on the wrong muscle group, we'll be activating the body for the opposite movement, which can complicate the construction of the position and the distribution of forces and weights.
Other methods at our disposal include using the vascular system, increasing irrigation in the area; or initiating the movement for that muscle to follow, verifying it's done correctly.
Active Core
This involves activating the core, or in other words, activating the musculature between the pelvic floor and shoulders.
For the tied person, this will allow maintaining posture and restriction more safely, while offering better response to movement initiated by the person tying.
Obviously, the person tying must monitor and, if necessary, activate the tied person's musculature.
For the person tying, initiating movements from the core will give them stability, fluidity, and efficiency.
For both parties, the experience gains intensity and safety.
A detail to consider: muscle activation requires energy, the body tires, and cannot maintain it indefinitely. Greater physical capacity means greater activation, but not necessarily for longer periods.
What Does Muscle Activation Provide?
First, maintaining muscle activation during practice provides safety, reducing injury risk for the tied person.
While muscles remain active, they fulfill their function, and loads or forces applied to the body won't affect other parts like ligaments, tendons, or nerves.
On the erotic level, muscle activation facilitates stimulation by increasing "sensitivity" through activation. There's greater irrigation, which supports the functions of various nerve receptors in the skin, while the active muscle mass is more "compact," favoring vibration transmission throughout the body. An active body will transmit and perceive all sensations with greater intensity.
Maintaining Muscle Activation
Maintaining muscle activation consumes significant energy, making it impossible to sustain indefinitely.
Each person, on each occasion, depending on their condition at that moment, can maintain it for varying periods, but usually for less time than we might imagine.
For this reason, the person tying must consider this when planning and managing the session. Management can be done through intensity modulation or applying rope techniques that reinforce body stability.
Remember that the biomechanical function of muscle activation is to provide joint stability.
Dynamic Range
Now we'll move the body, which is complex in itself, so we'll start with something essentially important: the concepts of active and passive dynamic range.
Dynamic range is a joint's range of motion.
Active range is the motion range achievable in a joint using only that joint's muscles and their strength.
In other words, it's our mobility range - movements we can perform without external help.
Passive range is the motion range achievable in that joint using external forces. It's always greater than the active range, and its maximum point is where we can't move the joint further.
These ranges aren't fixed and vary in the same person from day to day, and even throughout the session, as muscles activate and warm up, the person's active range will increase.
Regarding dynamic ranges, we must consider that when taking a joint to its passive range, its associated muscles deactivate.
This happens because the brain considers them unnecessary or doesn't know what to do with them in that range, so it resolves to deactivate them to conserve energy.
This means the joint becomes more unstable and the risk of damaging its passive structures increases.
Remember that if we ask the body for a movement, it will do whatever possible to provide it, and in this case, this means using tendons and ligaments to hold that position instead of muscles.
Because of this, it's important to progress gradually in restrictions, letting the body adapt and understand how to respond, while helping it through muscle activation and rope reinforcement.
Tension (テンション)
We've already said this is an active style, where both parties participate and are present throughout the session. One of the techniques used to achieve this is managing "body tension."
This "body tension" is simply the effect of muscle activation - the process by which our muscles engage, their fibers contract in response to stimuli received from the brain.
Tension is key, as it's the energy we use to communicate, like in the childhood example of a telephone made with two plastic cups and a string, where communication is impossible without tension.
This tension is important in both rope and body, and we achieve it by activating the musculature as explained in the theoretical section. We take advantage of reflexes to various actions we perform on the body, as demonstrated in the video. We can easily verify activation by touching the muscles - if they feel hard, they're active; if soft, they're inactive.