Nage-no-kata in judo: 15 throws in 5 groups, how the kata is structured, what you must be able to do first and why you learn it only with a teacher.
The honest answer: nage-no-kata is a closed forms sequence of 15 throws that you learn not from a book but from an experienced teacher, because order, etiquette and partner roles are precisely defined. It is traditionally learned in the dan range (practice; for the elective kata area the DJB explicitly speaks of "katas of the dan programme" [2]) and is therefore an advanced topic. That is why we classify it as "pro".
What lies behind it: Jigoro Kano developed the kata to show the principles of throwing so that students can apply them better in randori. It started with 10 techniques, and 5 more were added later, including kata-guruma and uki-otoshi [1]. It is one of the two randori-no-kata of the Kodokan [1].
Why the kata matters to you even if you never take a dan exam: the German Judo Federation understands kata in the original sense, namely practising techniques in closed situations rather than demonstrating a sequence [2]. In addition, 12 of the 15 techniques of the nage-no-kata are already part of the basic and extension programme for the kyu grades [2]. So you learn many of the throws beforehand; the kata merely orders them.
Honest up front: how long it takes until you run the kata cleanly depends heavily on teacher and federation. We give you no choreography here, because rebuilding a kata from memory would be exactly the mistake the kata is meant to prevent. Count in months to years.
The kata has 15 throws in five groups of three: te-waza (uki-otoshi, seoi-nage, kata-guruma), koshi-waza (uki-goshi, harai-goshi, tsurikomi-goshi), ashi-waza (okuri-ashi-harai, sasae-tsurikomi-ashi, uchi-mata), ma-sutemi-waza (tomoe-nage, ura-nage, sumi-gaeshi) and yoko-sutemi-waza (yoko-gake, yoko-guruma, uki-waza) [1]. Each throw is shown twice, once right and once left [1]. Milestone: you can recite groups and order without stumbling.
Before you run the kata, you master the throws individually the way your federation teaches them. The DJB names seoi-nage, harai-goshi and uchi-mata among others in the basic programme up to 4th kyu, and tomoe-nage and sumi-gaeshi in the extension programme [2]. Milestone: your coach confirms each throw individually as "secure".
The kata includes formalised behaviour: tori and uke enter the mat from different sides, bow standing towards the joseki and kneeling to each other, and then begin [1]. You learn the exact rules (reigi-saho) from your teacher. Milestone: you run the entry and exit of the kata without errors and without throws.
Usually one group (three throws) after another is practised, with the teacher within reach and clear roles. A study suggests that briefly watching movement models can complement learning a judo kata: in a group of 20 judoka, 5 minutes of watching in addition to practice improved biomechanical performance in go-no-sen-no-kata [3]. That is a transfer to a different kata, not evidence for nage-no-kata. Milestone: you run one group calmly without uke having to brake.
Only when all five groups work individually do you run the whole sequence, ideally with an experienced examiner or teacher watching. Milestone: you run all 15 throws, on both sides, without breakfall insecurity.
This guide explains and motivates; it does not replace supervised training or a coach.
Give each group one session just for uke. Anyone who can play the falling role cleanly understands why the order is built the way it is and learns tori faster. That is experience, not a study.
15 throws in five groups of three: te-waza, koshi-waza, ashi-waza, ma-sutemi-waza and yoko-sutemi-waza. Each throw is shown right and left [1].
Not for the kyu grades in the narrow sense. For the 2nd kyu the DJB allows only a selection of ten technical actions from dan-programme katas as an elective [2]. In the dan range it classically plays a role; what exactly is examined is regulated by your federation.
As a supplement yes, as a replacement no. Videos show one school; details differ, and the partner's breakfalls must be right. Learn the kata with a teacher from your federation.
The DJB notes that 12 of the 15 techniques are already in the basic and extension programme of the kyu exams [2].
It consists of real throws and is therefore as risky as throwing practice in general [5]. With secure breakfalls, a mat and supervision you lower the risk.
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