7-2. About Tension (Hariai)~How to release a grip (Torikake) naturaly~

Physical consideration of KYUDO -Japanese archery

7-2. About Tension (張り合い/Hariai)~How to release a grip (取り懸け/Torikake) naturaly~

<Tension (張り合い/Hariai)>Continued

Now, the balance of forces at full draw (会/Kai) can be expressed by the following equation:

Bow force = Force applied to the skeleton + Muscle strength supporting the skeleton + α (Force to extend both arms through the follow-through (残身/Zanshin))

When the draw (引き分け/Hikiwake) is over, this α is almost 0. During a full draw (会/Kai), this conversion of force is what we call tension (張り合い/Hariai). By making α as large as possible, you can produce a sharp, powerful and wide follow-through (大離れ/Oh-banare).

So, what exactly should we do?

As explained earlier, the force applied during the draw (引き分け/Hikiwake) is applied in the direction of folding the arm, while the force applied during the full draw (会/Kai) is converted into the direction of opening the arm. The force that guides the right hand straight through to the follow-through (残身/Zanshin) is applied starting from the right elbow.

Whether or not you can perform this internal power transformation, which is invisible from the outside, is the key to whether or not you can generate and cultivate the alpha that is the driving force behind the release.

It's important to note here that the pulling force should be applied starting from the right elbow, not from the hand or arm.

The reason is simple: If the release motion starts from the hand or arm, it occurs in an arc (3) centered on the right elbow, resulting in a larger displacement during the release.

Starting from the right elbow, the release motion occurs in a short arc (4) between the shoulder and the right thumb, centered on the right shoulder, allowing the right hand to release almost straight behind.

Given their physical positional relationship, there is no room for denial.

However, as a student, I couldn't understand the simple logic behind the instruction, "Draw the bow with your elbow." Prioritizing the length of the drawn arrow resulted in a bent right hand and a typical open release, leading to significant fluctuations in my performance.

(If you have enough arm strength to bend your arm, I recommend increasing the draw weight.)

If you apply force in the direction of opening your arm, won't that increase the draw length of the arrow?

You might think so.

However, as can be seen from the equation for the balance of forces at the draw, the force required to open the right hand to the follow-through position is small compared to the magnitude of the bow's draw force. Only the ratio with the muscle strength supporting the skeleton changes, so the arrow's draw length does not increase.

The important thing about tension is that, at the moment of release, the position of the thumbs of the left and right hands must not waver, so the direction of tension must be straight along the axis of the arrow.

And pulling it straight means that you have to pull it with your right elbow, as shown in (4) above.

On the other hand, the left hand should also be pushed straight in the direction of the arrow's axis, starting from the elbow, just like the right hand ((2) above).

By having both elbows as the starting point of force, balance is achieved, tension in the fingertips is prevented, and the left hand works effectively in sync with the force of the right hand.

Generally, people have difficulty performing independent movements with their left and right sides, and tend to perform the same movement if they don't consciously think about it. This is an undeniable fact.

It is difficult to perform different movements on the left and right sides of the body.

Next time, we'll be discussing ”Tension (張り合い/Hariai)”. We look forward to your next visit as you become more familiar with "hitting the target (的中/Tekichu)".