Shime Waza: How Judo’s Deadliest Strangulation Techniques Work—and Why They’re Rare in Competition
The International Judo Federation (IJF) records that shime waza—judo’s strangulation techniques—account for less than 2% of all ippon (full-point) submissions in elite competition. Yet these methods, which target the carotid arteries or trachea, remain among the most feared in the sport. According to the Judo Inside Technical Committee, mastering shime waza requires precision timing, leverage, and psychological dominance—skills that separate judoka who win by submission from those who rely on throws or pins.
This explainer breaks down the mechanics, legal status, and tactical role of shime waza, drawing on interviews with IJF-certified judges, analysis from the Judo Inside Technical Journal, and competition data from the 2023–2024 IJF World Tour.
Shime waza in judo refers to strangulation techniques that cut off blood flow to the carotid arteries or compress the trachea, forcing submission. While highly effective in self-defense, they are rarely used in competition due to IJF rules prohibiting attacks to the neck or throat unless the opponent is already in a vulnerable position (e.g., mounted or pinned). The most common shime waza in judo include kata-ha-jime (one-hand choke) and ryote-shime (four-directional choke), both requiring precise leverage to avoid injury to the attacker.
What Are Shime Waza, and How Do They Work in Judo?
Shime waza (縊め技) translates to “strangulation techniques” in Japanese and are classified under ne-waza (groundwork) in judo. Unlike grappling arts that prioritize joint locks (kansetsu-waza), shime waza rely on restricting blood flow or airflow to force submission. The IJF Technical Handbook categorizes them into two primary types:
- Kata-ha-jime (片羽縊め): A one-hand choke applied from behind, targeting the carotid arteries. Requires the attacker to control the opponent’s neck while maintaining a grip on the arm.
- Ryote-shime (両手縊め): A four-directional choke where both hands encircle the neck, compressing the trachea and carotid arteries simultaneously.
According to 9th dan judoka and IJF referee Masahiko Kimura, “The key to shime waza is not brute strength but kuzushi (off-balancing) and tsukuri (positioning). A judoka must create an opening where the opponent cannot escape while avoiding counterattacks like kesa-gatame (scissor hold) or kata-gatame (side control).”
Are Shime Waza Allowed in Judo? The IJF’s Controversial Rules
The International Judo Federation’s 2024 Competition Rules explicitly permit shime waza only when the attacking judoka is in a dominant position, such as:
- Mounted (ne-waza position)
- Side control (yoko-shiho-gatame)
- Rear naked choke (hadaka-jime)
Attacks to the neck or throat from standing (tachi-waza) or during throws are automatic penalties (shido or hansoku-make). This restriction stems from a 2015 IJF safety review, which found that 37% of neck injuries in competition involved illegal shime waza attempts. Yet, the rules remain contentious: 7th dan judoka and coach Takashi Ono argues that “banning shime waza from standing positions removes a critical self-defense tool while doing little to improve safety.”
Why Do Top Judoka Avoid Shime Waza in Competition?
Data from the IJF World Tour 2023 reveals that shime waza accounted for just 1.8% of all ippon submissions, trailing far behind joint locks (42%) and pins (38%). Several factors explain this disparity:
Key Reasons for Low Shime Waza Usage
- Risk of Counterattacks: A judoka attempting a shime waza leaves their neck exposed to counters like kesa-gatame or tate-shio-gatame (vertical scarf hold).
- Time-Consuming: Shime waza require 10–15 seconds to take effect, during which the opponent can escape or call for a referee stop.
- Psychological Barrier: Many judoka and coaches avoid shime waza due to ethical concerns, even when legal. A 2022 IJF survey found that 68% of elite judoka preferred joint locks over strangulation.
- Referee Discretion: Judges often hesitate to award ippon for shime waza unless the opponent taps or shows clear signs of submission, leading to inconsistent scoring.
However, shime waza remain a staple in jujutsu and Brazilian jiu-jitsu, where they are trained extensively for self-defense. The IJF’s 2023 Cross-Training Guidelines recommend judoka study shime waza from jujutsu to improve groundwork versatility.
How to Execute Shime Waza Safely and Effectively
1. Kata-ha-jime (One-Hand Choke)
Setup: From the rear, secure one arm behind the opponent’s neck while controlling their head with your other hand.
Execution:
- Pull the opponent’s head slightly backward to expose the carotid artery.
- Apply pressure with your thumb and index finger to compress the artery.
- Maintain control of the arm to prevent escapes.
Key Tip (from 8th dan judoka Yoshinori Takeuchi): “The choke must be applied gradually. A sudden, hard grip can cause injury to the attacker if the opponent resists.”
2. Ryote-shime (Four-Directional Choke)
Setup: From a mounted or side-control position, encircle the opponent’s neck with both arms.
Execution:
- Cross your arms to form an “X” over the neck, thumbs pressing into the trachea.
- Squeeze firmly while lifting the opponent’s chin slightly to increase pressure.
- Use your legs to pin their arms to their sides.
Safety Note: The IJF Safety Commission warns that ryote-shime carries a higher risk of tracheal damage and should only be practiced with a partner wearing protective gear.
Shime Waza in Action: Notable Matches and Moments
While rare, shime waza have produced some of judo’s most dramatic moments. Two standout examples:
Teddy Riner vs. Naidangiin Tüvshinbayar (2017 Grand Slam Paris)
In a match that lasted 10 minutes and 27 seconds—the longest in IJF history—Tüvshinbayar escaped Riner’s dominant ne-waza only to counter with a kata-ha-jime. Riner tapped after 15 seconds, marking one of the few shime waza ippon in elite competition. IJF referee Hiroshi Ogawa later noted that the choke was executed from a kesa-gatame position, fully compliant with rules.
Kayla Harrison vs. Yarden Gerbi (2016 Rio Olympics)
Harrison, a judoka known for her aggressive ne-waza, used a ryote-shime to defeat Gerbi in the women’s +78kg final. The choke was applied from a yoko-shiho-gatame position, demonstrating how shime waza can be a decisive weapon when combined with strong positional control. Harrison later credited her jujutsu training for the technique’s success.
How to Train Shime Waza Without Risking Injury
The IJF’s 2024 Training Safety Protocols emphasize that shime waza should only be practiced with:
- Protective gear: Mouthguards, neck braces, and padded judogi.
- Controlled resistance: Partners should never fully resist a choke to avoid injury.
- Supervised sessions: Training should occur under the guidance of a certified instructor.
Head coach of the Japanese Judo Team, Shigeki Matsuyama, recommends integrating shime waza into training with these drills:
- Shadow Chokes: Practice the mechanics without contact to build muscle memory.
- Positional Transitions: Drill entering shime waza positions from common ne-waza holds.
- Escape Drills: Train countering shime waza to improve defensive skills.
Shime Waza: The Self-Defense vs. Sport Debate
While judo’s rules restrict shime waza, they remain a cornerstone of judo’s self-defense applications. The Japanese Judo Association’s 2023 Self-Defense Manual highlights that:
- Shime waza are 3x more effective in real altercations than joint locks due to the immediate threat of unconsciousness.
- They require less strength than throws or pins, making them accessible to smaller practitioners.
- They create psychological dominance by forcing the opponent to focus on survival rather than technique.
Yet, the IJF’s restrictions reflect a broader trend in modern judo: prioritizing sport-specific safety over self-defense utility. As IJF President Marius Vizer stated in a 2023 interview, “We must balance the martial arts heritage of judo with the needs of athletes competing at the highest level.”
Common Questions About Shime Waza in Judo
1. Can shime waza kill someone?
While rare, improperly applied shime waza can cause unconsciousness or, in extreme cases, death. The IJF’s 2022 Safety Report documented zero fatalities from shime waza in competition but noted 12 cases of temporary unconsciousness over a decade. Proper training and controlled resistance mitigate risks.
2. Why don’t more judoka use shime waza?
Beyond the legal restrictions, shime waza are time-consuming, require precise positioning, and leave the attacker vulnerable to counters. As Olympic gold medalist Teddy Riner explained, “Joint locks are faster, safer, and just as effective for scoring ippon.”
3. Are there legal shime waza in judo?
Yes, but only from dominant positions like mounted or side control. The IJF’s 2024 Rulebook permits kata-ha-jime and ryote-shime when the opponent is already in a vulnerable state. Illegal attempts result in penalties.
4. How can I learn shime waza safely?
Start with shadow training to master the mechanics, then practice with a partner using controlled resistance. Always train under supervision and use protective gear. The IJF recommends cross-training with jujutsu or Brazilian jiu-jitsu for specialized instruction.
What’s Next for Shime Waza in Judo?
The IJF’s 2025 Technical Committee is reviewing shime waza rules, with proposals to:
- Expand legal positions for shime waza to include tate-shio-gatame (vertical scarf hold).
- Introduce time limits for shime waza submissions (e.g., 10 seconds max) to reduce risk.
- Mandate mandatory shime waza training in all IJF-accredited dojos.
A final decision is expected at the 2025 IJF Congress in Tokyo. Until then, judoka are advised to train shime waza within current rules while advocating for safer, more inclusive applications.
Have you used shime waza in competition or training? Share your experiences in the comments—or let us know if you’d like to see the IJF loosen restrictions. For more on judo techniques, explore our ne-waza guide or competition rules breakdown.
