01 / AT A GLANCE
A strangle made by a triangle of legs
Sankaku-jime (三角絞) is one of the twelve shime-waza (strangling techniques) in the Kodokan list of technique names, inside the katame-waza group. “Sankaku” means triangle; the IJF gives the English name “triangular strangle”, and many English-speaking clubs say “triangle choke”.
The IJF definition describes it facing the opponent: wrap your right leg over uke’s left shoulder and your left leg under uke’s right armpit, catch your right foot under the back of your own left knee “in a triangular leg formation”, and squeeze the neck from that position. The legs do the strangling; the hands are not named in the definition.
The same leg triangle appears in another Kodokan technique, ude-hishigi-sankaku-gatame, a joint lock in which the hands extend uke’s elbow. Coaches also use the triangle to turn uke over into a hold. This page is about the strangle; section 12 sets the three apart.
Reader: a judoka whose coach has already shown how strangles are applied and released. Text cannot replace that lesson. Practice ends at the tap and never continues towards unconsciousness.
Names you will meet: sankaku-jime, sankaku jime, triangular strangle and triangle choke refer to this Kodokan technique. Names such as mae-sankaku, yoko-sankaku or ushiro-sankaku are informal coaching labels for the direction you attack from; the Kodokan list has a single entry, Sankaku-jime.
02 / WATCH THE TECHNIQUE
The Kodokan demonstration and a coach’s class notes
Open this video on YouTube if the player is unavailable.
We stepped through this clip at intervals of a few seconds rather than frame by frame. What we could see: the pair start sitting and kneeling face to face. Tori then lies on the back with uke kneeling over tori and between tori’s legs. One of tori’s legs comes up over uke’s shoulder and behind the neck, and uke’s head is held low against tori’s body. In the side views tori’s hands hold one of uke’s arms by the sleeve near tori’s chest, inside the legs. The clip repeats the action from several camera angles, including one from behind tori’s head and close-ups of the head and arm.
Watch it with the IJF wording beside you. Look for: which leg goes over the shoulder; where the other leg passes relative to uke’s armpit; where the right foot is caught; what tori’s hands do with uke’s arm; and whether uke’s head is pulled or simply held. Mark anything the camera hides as “not visible” rather than filling it from memory.
Open this video on YouTube. Independent coaching reference, separate from the official demonstration.
We have not reviewed this coaching video by playback, so no specific instruction here is attributed to it. Its publisher chapter list maps the topics: definition (0:00), explaining the triangle (0:13), footwork (0:20), closing off the carotid arteries (0:40), pull uke’s arm straight (1:05), sankaku-jime uchikomis (1:52), battlefield origins (2:54), “wrasslers” (3:06), overcoming flexibility challenges (3:28), “judo ≠ gentle way” (4:10) and grab higher on uke’s sleeve (4:38). These are publisher cues, not timestamps we checked.
Three chapter titles connect to questions on this page: “pull uke’s arm straight” and “grab higher on uke’s sleeve” both concern the arm inside (section 4); “overcoming flexibility challenges” is relevant if your foot will not reach your knee (section 6). Ask your coach to show what they mean by each.
03 / WHEN TO APPLY IT
Opportunities come from uke’s head and one arm in front of you
Sankaku-jime is attacked facing uke. You need uke’s head within reach of your legs and one of uke’s arms on the inside, with the other arm outside. The positions that offer this are quite specific.
Uke kneels between your legs
This is the position in the Kodokan clip. You are on your back and uke is inside your legs, trying to pass or to strangle. If uke’s head comes forward and one hand is placed on your body or on your jacket while the other is not, the arrangement the triangle needs is already partly there.
Uke turtles in front of you
When uke is on hands and knees with the head towards you, coaches teach triangle entries from the front or the side. Uke’s head is low and the arms are near it, so one leg can pass over a shoulder. These entries frequently lead to a turnover rather than a strangle on the spot; section 9 covers that branch.
Uke reaches in with one arm
A single arm reaching in to grip your collar or push your hips is the classic invitation: that arm can stay inside while the other remains outside. Two arms reaching in at once, or two arms held outside, do not offer the shape.
When it is not available
If both of uke’s arms are outside your legs, closing your legs round the neck alone is not sankaku-jime and is penalised in IJF competition (section 11). If uke is upright with the head well away from you, the leg cannot reach over the shoulder without first breaking that posture. If uke is standing, a strangle is not permitted: under the IJF rules, shime-waza from the standing position is stopped with mate. And if your hips are pinned flat under uke’s weight, you will struggle to raise the legs; recover space first.
04 / HOW IT WORKS
Posture, arm inside, leg over, foot locked, then squeeze slowly
The IJF definition fixes the legs and the lock. It does not specify grips, hip angle or how hard to squeeze, so those come from your coach. Each stage has a check uke can report before any pressure.
Bring uke’s head down before the legs move
From the position with uke kneeling between your legs, your grips on uke’s sleeves or collar and your knees draw uke’s posture forward so that the head comes within reach. A coaching chapter title suggests a higher sleeve grip; ask your coach where yours should be. Check: before any leg moves, can you touch the back of uke’s neck with your right lower leg without uke having to bend further? If not, the leg will arrive late and uke will straighten up.
Set one arm inside, one outside
The triangle must enclose the neck and one arm. Hold the arm that will stay inside close to your body by the sleeve or wrist; in the demonstration tori’s hands hold uke’s arm near tori’s chest. The other arm should be outside the triangle. Check: before the leg goes over, say which of uke’s arms is inside and confirm it with uke. If both are outside or both inside, reset.
Right leg over the left shoulder and behind the neck
Lift the right leg over uke’s left shoulder so that the back of the thigh and knee crosses behind uke’s neck. The leg should lie across the neck and shoulder, not on top of the head. Check: uke reports where the leg is. “On my head” or “on my upper back” means the leg is in the wrong place.
Left leg under the right armpit, right foot under the left knee
Bring the left leg under uke’s right armpit and fold it so that your right foot is caught under the back of your left knee. This is the triangle in the definition. The lock is a foot behind a knee, not two crossed ankles. Check: the coach sees your right instep in the bend of your left knee. If your feet are crossed at the ankles instead, the shape is different and does not close the triangle.
Squeeze slowly, with the arm still inside
From the locked triangle, squeeze the neck by closing the legs, as the definition says. Increase gradually from almost nothing so uke can tap early. A coaching chapter mentions pulling the arm straight; do not substitute a pull on the head for the leg squeeze. Pulling uke’s head down with your hands loads the neck and spine, and any action that may endanger the neck or spinal vertebrae is a hansoku-make act under IJF rules. Check: uke reports pressure on the sides of the neck from the legs and the trapped shoulder, not a bending of the neck.
Release by opening the lock
On a tap, a spoken “stop”, any sign of distress or any doubt, take the right foot out from behind the left knee and open both legs. Do not simply relax the squeeze while staying locked. Uke’s inside arm may be held, so agree before each round that a tap with the free hand, a foot tap or a spoken “stop” all count. If uke stops responding, open the legs, call the coach and end the drill.
What closes uke’s escape paths: the posture break stops uke standing up out of reach; the arm inside stops uke using both hands against your legs and keeps the triangle legal; the knee lock stops the legs being pried open; and your hips facing uke stop uke stepping round. Each fails in its own way, which is why the problems below are separate.
05 / KEY POINTS
Four checks under resistance
Take one per session and record it after each round.
The arm inside stays inside until you release
Check: after every attempt uke says whether the arm was in when the triangle closed and when it was released. Any “no” is a stop, not a partial success.
Foot behind knee, never ankles crossed round the neck
Check: the coach calls “show me the lock” and you pause. Count how often the right instep is in the bend of the left knee.
Head down before the leg rises
Check: film from the side. In each attempt, note whether uke’s posture was already broken when the right leg started upward. Attempts with an upright uke tend to be the ones where uke stood up.
The squeeze comes from the legs, not the hands
Check: for three repetitions keep your hands only on uke’s inside arm. If uke still reports the strangle building, the triangle is doing the work. If it only works when you pull the head, fix the triangle first.
06 / PROBLEMS & ADJUSTMENTS
Why does your sankaku-jime fail?
Identify the first stage that broke: posture, arm, leg position, lock or squeeze. Each has different causes.
“Uke stands up as soon as my leg comes up.”
Possible causes: uke’s posture was never broken, so the head was out of reach; your grips were on the wrong place to pull uke forward; or you raised the leg slowly while uke watched it come. How to tell: freeze the video at the moment the right leg starts to rise and look at uke’s back: rounded towards you or upright? Adjustment: spend a block on posture breaking alone: you on your back, uke kneeling, and the only task is to bring uke’s head within reach and keep it there for a few seconds. Add the leg only after that works at moderate resistance. Assess: how often the leg reaches the back of the neck with the same partner and resistance.
“My foot won’t reach the back of my knee.”
Possible causes: the triangle is too loose because the right leg is too far down uke’s back; your hips are square to uke when your coach would have them angled; or a genuine flexibility or leg-length limit for this partner’s size. How to tell: try the lock on a smaller partner at no pressure. If it closes easily there, it is a size or position issue with this partner; if not, it is the shape. Adjustment: ask your coach to show the hip position for your body; the coaching video’s chapter on flexibility is a starting point for that conversation. Never force the knee down with a hand on uke’s head to make the lock. Assess: the number of locks completed at no pressure, then at light resistance, on the same partner.
“Uke pulls the arm out and the legs are just round the neck.”
Possible causes: your hands let go of the inside arm while you worked on the lock; the arm was only lightly inside, at the forearm; or uke pushed down on your hip to free it. How to tell: ask uke at which moment the arm came out. Adjustment: stop the attempt immediately and open the legs. Under the IJF rules legs around the neck without an arm inside are stopped with mate and shido. Then work on holding the arm by the sleeve, higher up, while the lock is made. Assess: repetitions in which uke confirms the arm inside from lock to release.
“Uke says it feels like a neck crank.”
Possible causes: you are pulling uke’s head down with your hands to make up for a loose triangle; the right leg is on the back of the head rather than the neck; or uke is being folded forward under your legs. How to tell: uke reports where the pressure is. Discomfort at the back of the neck or the upper spine, with little at the sides, is the warning. Adjustment: release fully. Re-place the right leg on the neck and squeeze with the legs only, hands on the arm. If that produces nothing, the triangle shape is the problem, not effort. Assess: three slow repetitions with pressure reported at the sides of the neck and no head pulling.
“Uke drives forward and my legs collapse.”
Possible causes: uke has stacked your hips over your shoulders and is pressing weight onto you; your lock was incomplete when uke started forward; or your head and neck are bearing uke’s weight. How to tell: the coach looks at your own neck. If your chin is being pushed onto your chest, you are the one at risk. Adjustment: stop: open the legs and reset. In drills, agree that uke does not stack onto tori’s neck. Ask your coach how to angle your hips so the triangle is completed before uke can drive forward. Assess: fewer collapsed attempts with the same agreed resistance.
“The lock is on but nothing happens.”
Possible causes: the triangle encloses the arm but the neck is not snug against it, so the squeeze closes on space; your legs are pressing the jaw or face; or uke has turned the head to relieve the side of the neck. How to tell: uke reports where the legs feel tight. Adjustment: release and rebuild in order: posture, arm, leg, lock. Do not squeeze harder, and do not pull the head. Assess: how often uke reports the neck contact before you start the squeeze.
07 / SETUPS & BRANCHES
What uke does with the arm inside decides the next action
Each sequence lists the start, the first action, uke’s response, the next action and when to stop.
ONE ARM IN → TRIANGLE
Uke reaches in with one hand from between your legs
Start: you are on your back, uke kneels between your legs. First action: break uke’s posture with your grips and knees. Response: uke posts one hand on your chest or reaches for your collar, leaving the other arm outside. Next action: hold the inside arm, swing the right leg over the shoulder of the outside arm and complete the lock as in section 4. Stop: if uke withdraws the inside arm before the lock, do not close the legs on the neck; return to guarding with the legs and grips.
STRANGLE → LOCK
The strangle is defended but the inside arm straightens
Start: triangle locked, arm inside. First action: slow squeeze. Response: uke protects the neck by posturing, and the inside arm straightens across your body. Next action: if your coach has taught it and the rules of your practice allow it, the same triangle can become ude-hishigi-sankaku-gatame, in which your hands extend the elbow. That is a different technique with its own safety rules: extend the elbow slowly, only at the elbow. Stop: if you are not practising joint locks in this session, release and reset rather than improvise.
TRIANGLE → HOLD
Uke stays square and heavy, and the strangle will not close
Start: triangle on, but uke has a strong base. First action: light squeeze. Response: uke pushes forward or to one side to relieve the neck. Next action: coaches teach rolling uke over with the triangle still on and finishing on top. Under the IJF osaekomi definition, “sankaku situations” are among the recognised holding positions, but only when you control uke’s upper body as a hold requires. Stop: if the roll would twist uke’s neck, open the legs first.
TURTLE → TRIANGLE ENTRY
Uke on hands and knees with the head towards you
Start: uke turtled facing your side or front. First action: the entry your coach teaches to get one leg over a shoulder. Response: uke tucks the near arm and lowers the head. Next action: if one arm is inside, complete the lock and decide between the strangle and a turnover according to how uke reacts. Stop: if both arms end up outside, there is no legal triangle; reset.
Keep a note of what uke did when you closed the legs: posture up, pull the arm, drive forward or roll. These responses decide the branch.
08 / DEFENCES & ESCAPES
Never give one arm in, one arm out
Treat defence in three layers: prevention (do not offer the shape), defence (stop the lock or the squeeze) and escape (leave the triangle).
Prevention: posture and both arms together
When you are between tori’s legs, keep your back straight and your head up, away from tori’s chest. Keep both hands on the same side of tori’s legs: both in on tori’s body or both out controlling the knees. Reaching in with one arm is the shape the strangle needs.
Defence: stop the lock forming
If tori’s leg comes over your shoulder, work to keep tori from catching the right foot behind the left knee. Removing your inside arm before the lock closes takes away the triangle. Do not pull an arm out of a closed triangle by force while the squeeze is on; tap instead.
Escape: posture and turn, as your coach teaches
Escapes from a closed triangle involve posture, hip position and freeing the inside arm. Standing up and lifting tori off the mat is not a drill for supervised beginners, and in IJF competition the referee calls mate when an athlete stands and lifts an opponent who is lying on the back with the legs around them clear of the tatami (Article 11.2(f)). Learn the escape your coach teaches, and if the pressure builds while you are escaping, tap.
Counters and exposure
Do not try to escape by slamming or lifting tori off the mat and dropping them. Do not drive your weight onto tori’s neck to collapse the legs. If the arm comes free, tori is likely to release anyway: wait for the release rather than wrenching.
09 / LOCKS, HOLDS & TURNOVERS
The triangle as a hub between strangle, lock and hold
The leg triangle connects three different outcomes in judo. Knowing which one you are aiming for keeps practice safe and prevents confusion.
From guard to the strangle
The Kodokan clip shows the strangle with tori on the back and uke between the legs. If uke postures up out of reach, return to grips and posture breaking. If uke stands, release; strangles from the standing position are stopped in IJF competition.
From the strangle to the armlock
When the inside arm straightens, the triangle can lead to ude-hishigi-sankaku-gatame. Treat it as a separate skill to learn from its own guide and from your coach, with its own release rules.
From the triangle to a hold
A turnover with the legs locked can end with you on top. The IJF rules list “sankaku situations” among the positions in which osaekomi can be applied, but they also stop holds that control only the head and neck: legs around the neck without an arm inside are stopped with mate and shido. The arm inside matters for the hold as much as for the strangle.
When the triangle opens
If uke frees the arm or the lock breaks, return to guarding with your legs and grips, or recover a safe position. Do not chase the neck with the legs alone.
For session design that ties these together, see the ne-waza drills guide and the ne-waza training plan.
10 / POSITIONAL ROUNDS
From a still triangle to a live positional round
Add one difficulty at a time and agree the stop signals, including a foot tap and a spoken “stop”, before each stage. Durations are editorial suggestions to adapt with your coach.
Shape only, no squeeze
Uke kneels, tori lies down. Tori sets the arm inside, puts the right leg over and makes the lock. Uke names which arm is inside and where the leg is. Progress when the foot-behind-knee lock is made on the right place three times in a row.
Light squeeze and release drill
Tori squeezes slowly with the legs, hands only on the arm; uke signals early, alternating hand, foot and voice. The coach checks that tori opens the lock fully every time.
Posture-breaking round, no triangle
Uke tries to sit up with good posture; tori tries to bring the head into reach and keep it. This isolates problem one.
Arm-reaction decision drill
Uke offers both arms in, both out or one in, at the coach’s call. Tori attacks the triangle only when one arm is in and the other is out. Count correct decisions; no squeeze.
Controlled positional round
Uke defends with an agreed defence and agrees not to stack onto tori’s neck. Tori may close the triangle and squeeze at controlled intensity. Record three outcomes: triangle locked, arm lost, uke postured out.
Stage 5 working with one partner does not mean it will work with a heavier or more flexible partner. Change one variable at a time.
Who supervises: a coach who can see both players. Without one, keep to stages 1, 3 and 4.
11 / COMPETITION & RULES
Two IJF replay leads, and what the rules say about the triangle
On October 14, 2026 the IJF Sankaku-jime technique page listed athletes with the most tagged contests, headed by Damian Szwarnowiecki (Poland, 9) and Lubjana Piovesana (Austria, 8). Each athlete page is headed “Sankaku-jime by …”, crediting the tagged action to that athlete. We have not verified whether it scored, the time, or any tactics, and we have not watched the footage.
World Championships Baku 2018: Szwarnowiecki vs Khalmurzaev
The IJF sankaku-jime selection for Damian Szwarnowiecki lists his contest (POL, white) against Khasan Khalmurzaev (RUS, blue) at the World Championships Seniors Baku 2018.
Baku World Championships 2026: Kim vs Piovesana
The IJF sankaku-jime selection for Lubjana Piovesana lists her contest (AUT, blue) against Kim Yeji (KOR, white) at the Baku World Senior Championships 2026.
Viewing questions
- The entry: was the attacker underneath with uke between the legs, or entering on a turtled opponent?
- The arm: which arm is inside the triangle, and does it stay there?
- The lock: can you see the foot caught behind the knee?
- The branch: does the action end as a strangle, a lock, a turnover to a hold, or a break?
- The ending: record only what you see: tap, referee intervention or mate.
Rule points we verified
We read the official IJF SOR Refereeing Rules PDF in the version the IJF lists as 21.01.2026 (checked October 14, 2026). In that version: in shime-waza, a “sankaku situation gripping the head with the legs just around the neck” with the legs assisting the grips “without any arm of the opponent” is mate and shido (Article 18.1.2, point 26; point 27 in the March 12, 2024 edition); in Article 17, control in ne-waza with the legs around the neck without the opponent’s arm inside is likewise mate and shido; applying do-jime, a separately listed Kodokan strangle, is hansoku-make (Article 18.2.2, point 3); shime-waza from the standing position is stopped with mate, and the current text adds that shido will be given (Article 11.2(g)); any action that may endanger the neck or spinal vertebrae is hansoku-make (Article 18.2.2, point 7(a); point 8 in the 2024 edition); and a contestant gives up by tapping twice or more with the hand or foot or by saying “maitta” (Article 14). Article 20 adds that a cadet who loses consciousness during shime-waza cannot continue in the competition. Remember that national and youth rules may differ.
A naming trap: the same rules mention a “kata-sankaku grip”, defined there as gripping the neck and one shoulder with both arms. It is an arm grip with its own rules in standing judo, not sankaku-jime.
12 / VARIATIONS & COMPARISONS
Three things called “sankaku”
| Name | What it is |
|---|---|
| Sankaku-jime | Kodokan shime-waza. Leg triangle around the neck with an arm inside; the legs squeeze the neck (IJF definition). |
| Ude-hishigi-sankaku-gatame | Kodokan kansetsu-waza (IJF page name “Sankaku-gatame”). Same kind of leg triangle, from the front, rear or side; one or both hands extend and control uke’s elbow. |
| Sankaku turnover to a hold | Not a separate Kodokan technique. The triangle is used to roll uke over; the result is judged as osaekomi, and the IJF rules list sankaku situations among holding positions. |
| Kataha-jime and other rear strangles | Arm and lapel strangles from behind uke. They share the shime-waza classification, not the mechanics. |
Direction labels: coaches speak of front (mae), side (yoko) and rear or reverse (ushiro, ura) triangles for the direction from which the legs are applied. These are informal names. If the legs form the triangle around the neck and one arm and the legs do the strangling, it is still sankaku-jime; if the hands extend the elbow, it is the armlock.
Not a leg scissor: crossing the ankles around the neck alone, or squeezing the trunk with crossed legs, is not sankaku-jime. Do-jime is a separate Kodokan strangle that the IJF rules list as hansoku-make, and legs around the neck without an arm inside are penalised.
Other sports: the triangle is common in other grappling sports under other rules. Judo’s arm-inside rule, its mate for standing strangles and its mate when a lying opponent is lifted clear of the tatami apply here; do not import other rule sets.
13 / YOUR NEXT PRACTICE
One focus: one arm in, one arm out
Use this record for one session built around the decision drill in section 10.
- Situation
- Tori on the back, uke kneeling between the legs; controlled resistance; no stacking.
- My focus
- Attack the triangle only when one of uke’s arms is in and the other is out.
- What I noticed
- How many times was the arm still inside when I locked? Did my foot catch behind my knee? Did uke ever report the back of the neck?
- Coach question
- “Which arm should be inside in your version, and where should my hips be for my leg length?”
- Next decision
- Stay on posture breaking, move to the controlled round, or learn the turnover branch.
Illustrative example, not measured data: “Ten starts. I locked the triangle four times; the arm was inside every time but uke stood up out of two others before my leg rose. Next session: posture-breaking rounds first, then the shape drill.”
Keep your notes in the practice-log template or in Judo AI, and record what uke did when the legs closed.
14 / SOURCES & REVIEW
Sources, authorship and review
The name, kanji and classification come from the Kodokan list of technique names, which also lists ude-hishigi-sankaku-gatame among kansetsu-waza and do-jime among shime-waza. The leg triangle comes from the IJF sankaku-jime definition, and the lock comparison from the IJF Sankaku-gatame definition (both checked October 14, 2026). Rule references are from the IJF SOR Refereeing Rules, version listed as 21.01.2026 and checked October 14, 2026, linked from the IJF documents page.
By Judo AI · Editorial review: October 14, 2026. Coaching suggestions, diagnoses and drills are editorial proposals for supervised practice, not a validated programme. No named coach has reviewed this page. The Kodokan clip was stepped through at intervals of a few seconds; the coaching video is cited only through its title, description and publisher chapter list.
Not verified: which of uke’s arms is inside in the Kodokan form (the IJF wording names the legs only and the clip angles did not settle it for us); recommended grips and hip angle; the content of the coaching video’s chapters; scores or timing in either IJF listing.
Related katame-waza guides: ude-hishigi-sankaku-gatame (the triangle armlock), kataha-jime, okuri-eri-jime and hadaka-jime (strangles), ude-hishigi-juji-gatame (armlock).