Understand hadaka-jime in judo: principle, position, tap rule and safety. A guide to understanding, not a home manual – train it only under a coach.
The honest answer: hadaka-jime is a choke from behind that squeezes the blood vessels in the neck – and that is exactly why you learn it only with a coach, on a mat, with a partner who may tap and whose tap counts instantly. The name means "naked choke" because it needs no grip on the judogi. The German Judo Federation lists it in its extended programme for teenagers and adults [1].
This guide is a guide to understanding. You get the principle, the position and the safety rules – but deliberately no step-by-step manual for choking someone. That belongs in the hands of a coach who sees what you do not.
Why so strict? Medical authors describe sport chokes as compression of the neck veins and, with more force, the carotid arteries. The word "choke" is misleading because it is about vessels, not the airway [4]. With a fully established hold, unconsciousness typically occurs after 6–14 seconds – shorter than saying two sentences [4].
The following steps describe the learning build-up, not the execution on a partner.
First you learn what a blood choke is and is not. In hadaka-jime the pressure sits at the sides of the neck, not on the throat. The coach shows you on a diagram or model why this throttles blood flow to the brain. Milestone: you can explain why time is the risk factor.
With the coach you practise control from behind: keeping balance, not jerking the partner, communicating calmly. Nothing is squeezed. The federation stresses that all katame-waza are learned so that tori controls the partner even when he tries to escape [1]. Milestone: you hold the position steadily without the coach having to step in.
You are uke first, the one who gives the signal. The federation wants uke to carry responsibility for the interaction [1]. You practise tapping early and clearly, with hand or foot, and saying "stop". In IJF rules, tapping twice with hand or foot, or "Maitta!", ends the contest [2]. Milestone: your tap comes before it gets unpleasant.
The coach demonstrates and corrects. You practise only the shape of the entry, without pressure and without speed. You practise releasing just as much as setting up. Milestone: you release at the very first sign.
Only when your coach has seen control, calm and your release reflex does choking under supervision come in. Not before.
This guide does not replace supervised training or a coach. You practise chokes only in training, under supervision, with a partner who may tap.
Truly good choke specialists train something other than the hold: letting go. Whoever learns to open up at the first twitch is the partner everybody wants. That earns you more training partners than any new variation.
The German Judo Federation lists hadaka-jime in its extended programme for teenagers and adults [1]. When your club clears it is your coach's decision.
With supervision, a tap rule and immediate release, sport chokes can be trained safely. Without those rules it can lead to unconsciousness and rare severe vessel injuries [4][5].
With a fully established hold, unconsciousness typically occurs after 6–14 seconds [4]. That is why the tap must come early.
No. You may only practise movement patterns without neck pressure, and only with a coach and a partner. No choking a partner without supervision.
Release at once, call the coach, watch your partner and do not leave him alone. Call emergency services if breathing is a problem or he does not come round quickly.
Understanding Okuri-eri-jime: The Sliding Collar Choke – Core Judo, Only With a Coach