Purpose

A triangle with both of the opponent’s arms outside the leg loop is a neck choke only — one side of the neck is compressed by the shin, but the opposite carotid has no direct compression because no structure is pushing it into the shin from the other direction. When one arm is trapped inside the loop (across the body, hand past the hip), the arm itself becomes the compressor on the inside carotid — the trapped arm pushes the artery into the shin while the shin pushes from the other side. This bilateral compression is what makes the triangle choke efficient.

The arm must be pulled across — not just left inside by accident. Opponents who have both arms outside or who can retract the inside arm after the triangle closes will survive longer than those caught with the arm isolated. This drill trains the deliberate clearing movement: identifying which arm is inside, pulling it across the body, and securing it before the leg lock closes.

Setup

The open triangle position is established: right leg over the right shoulder, hips slightly elevated, left leg free. The partner’s right arm is inside the triangle (between the practitioner’s right leg and their own body). The partner will attempt to retract the arm — they pull it back toward their centre line — but do so slowly and without full force.

Execution

From the open triangle, identify the inside arm (the right arm — it is inside the triangle between the right leg and the partner’s body).
Reach the hands down to the inside arm — grip the wrist, or reach under the elbow to control the forearm. The goal is to move this arm across the partner’s body (from right to left — from inside the triangle to outside the left side of the body).
Pull the arm across while simultaneously closing the triangle with the legs. The arm moves to the far side (left side) of the partner’s body. Once past the centreline, the arm is effectively trapped — the leg lock prevents it from returning.
Close the leg lock (DRILL-TRI-02 geometry) around both the neck and the trapped arm simultaneously.
Check: the trapped arm’s elbow should be past the centreline — the hand is on or past the opposite hip. The partner’s shoulder is pressing against the shin from inside the loop.
Release and reset.

Partner role: Semi-cooperative — slow resistance on the arm retraction (pulling back toward centre) to provide the practitioner with a light working load against which to practice the clearing movement. Not full resistance.

Coaching Notes

Students who close the triangle before securing the arm end up with an arm that is inside the loop but not cleared — the elbow is still near the partner’s own centreline, and the arm can slip back out as the opponent postures or twitches. The arm must be pulled past the centreline before the lock closes, not after.

The timing of the arm clear and the leg lock closure is the skill here. Some students try to clear the arm after the triangle is closed — but with the lock in place, the arm’s range of motion is restricted by the legs, making the clear harder. Clear first, then close.

The grip on the arm matters. A wrist grip pulls the arm across but can be slipped. An elbow grip (forearm under the elbow, lifting and pulling) is more secure but requires more reach. For Foundations-to-Developing students, the wrist grip is easier to locate — teach the elbow grip as the progression.

Common Errors

Triangle locked before arm is cleared: The leg lock closes with the arm still inside but not across the centreline. The arm can slip out during scrambling. Clear the arm first, then lock.

Arm cleared but not past the centreline: The arm has been moved but the elbow is still near the partner’s centre. The arm can return. Pull until the hand is past the opposite hip.

Pulling the wrong arm: The practitioner clears the arm that is outside the loop — the one that is not inside the triangle. Only the inside arm (the arm between the choking leg and the partner’s body) needs to be cleared.

Releasing the arm after clearing: After pulling the arm across, the student lets go before closing the triangle. The arm returns to the inside position. Maintain grip on the arm until the leg lock is secured.