Kanuki Shibari has a precise purpose and clear application: to provide excellent torso support during suspensions — both static ones and, especially, those involving transitions — making body management easier in all cases.
To better understand its overall structure, let’s first break down each component:
Anchor Point - Tenbindori (天坪鳥)
This is the initial tie that stabilizes the shoulder joints and serves as the anchor for the entire structure.
It has a dual role: first, to secure the rope to the body so the rest of the harness can be built; second, to begin managing body tension by giving the tied person an initial cue to engage upward with intensity and direction.
In other words, the force vectors it generates converge along the spine in an upward direction.
First Line - Une no Nawa (上の縄)
This line encircles the body, stabilizing the shoulder joint complex and connecting the hon musubi (as an extension of the sacroiliac joint) with the sternoclavicular joint.
Its function is to regulate body activation and response, establishing the kinetic and muscular chain the tied person uses to “push upward.”
For that reason, its direction is descending — the force vectors converge along the spine downward.
Stem and Knot - Jiku (軸) Battendome (ばってん止め)
The stem is the vertical line created when the rope travels from the hon musubi to the first line, locking both structures together through a knot or stopper.
It works as a connector, distributor, and insulator for the forces generated throughout the tying and suspension process.
Second Line - Shita no Nawa (下の縄)
Formed by a set of ropes that wrap around the lower thoracic area.
Its main role is to provide tactile reinforcement, helping the tied person better engage their core during the session.
Its load is directed backward and downward, acting on the core and pelvic floor.
Lock - Yotsudome (四留)
With its signature S-shape, this component compresses the lines, adjusts their tension, and creates a solid anchoring point that will later serve to attach the lifeline.
Tie Rod - Kanuki (門)
Placed one on each side, they adjust the tension of the lines and provide tactile feedback to the lateral muscles.
Dorsal Band - Tasuki (襷)
This is the first “extra” section of the kanuki. It’s often referred to as a “third” line and serves three functions:
- It reinforces and protects the dorsal region, which increases muscle engagement and improves pelvic balance.
- It adds an additional downward and backward load that, combined with the second line, creates a negative shift in the ground reaction force (GRF).
- It supports overall stability and body control.
Lark’s Head - Hibari (雲雀)
This is the final reinforcement for the forearms. Since the initial one loses efficiency at this stage, this additional element enables the tied person to push and lift themselves during suspension.
Its vectors act inward (toward the spine) and upward (toward the lock).
From a biomechanical standpoint, the entire structure is designed to generate a negative load in the ground reaction force, which reverses once the lifeline is connected — thereby facilitating the body’s lift into suspension.
For this reason, the tie only makes sense when suspension is intended. It should not be prolonged on the ground, since Kanuki Shibari demands sustained muscular engagement from the tied person. This effort can quickly become exhausting and has a limited “active lifespan.”
In short: the longer the tie remains grounded, the less useful time it will offer once in suspension.