Learn uchi-mata, the judo inner thigh throw: kuzushi, turn-in and leg. Honest and safe, with breakfalls, rules knowledge and a partner under supervision.
The honest answer: uchi-mata is a throw in which your leg swings between Uke's legs and meets his inner thigh while his hip tips over yours. It looks elegant and is nevertheless among the throws that demand the most coordination in the kyu programme: the German Judo Federation counts it among the coordinatively more demanding techniques of 5th kyu and makes it mandatory at 4th kyu, next to o-soto-gari and harai-goshi [1].
Honestly expect months, not weeks. That is a practical rule of thumb, not a study. In return, uchi-mata rewards you with a throw that works from many grip and distance situations. Whether it is among the most frequent throws in competition cannot be proven from the sources we read. But it is among the throws that the rules mention by name, once as an example of forbidden diving with the head and once as a permitted technique with an entwined leg [2].
One hand on the sleeve, the other on the lapel. Upright, knees slightly bent, eyes forward. Milestone: you lead Uke evenly without leaning back yourself.
With pull and lift you bring Uke forward and sideways onto his toes. A case study on the related harai-goshi suggests that shifting Uke's centre of mass towards the pulling hand should precede the turn-in [3]. For uchi-mata this is a transfer; harai-goshi was measured. Milestone: Uke stands on his toes without you yanking on the arms.
You turn in and set your standing leg between Uke's feet, hip close to his. The standing leg stays slightly bent, you stay upright and your head up. Milestone: you hold the position for one second without tipping forward.
The throwing leg swings backward and upward between Uke's legs and meets the inner thigh with the top of your leg. In competition an entwined leg in uchi-mata is explicitly permitted and scored as long as you start the throw immediately [2]. Milestone: in uchi-komi your leg meets Uke's inner thigh without you losing balance.
With your coach's approval you throw for the first time with reduced swing. The pulling hand draws Uke in an arc around the hip and accompanies him to the landing. An ippon needs speed, force, landing on the back and controlled landing [2]. Milestone: Uke lands under control, you remain upright.
Three things count. First the head: uchi-mata is on the list of throws for which diving head-first counts as dangerous and is punished with hansoku-make [2]. Second the standing leg: in three elite judoka the hamstring tendon of the supporting leg ruptured after they abruptly extended the knee with the hip flexed. Which throwing techniques were involved is not named in the abstract [4]. A hint to extend the standing leg in a controlled way when straightening up. Third the force: being thrown is the most common injury mechanism in judo [5]. So: you only throw partners who can do ukemi securely, on tatami and under supervision, and at the start with reduced swing. As Uke never deliberately go into a bridge: the rules score a voluntary bridge as ippon for tori in order to protect the cervical spine [2]. This guide explains and motivates, it does not replace supervised training.
If the throw does not work, abort instead of saving it. Uchi-mata is a throw with high balance demands, and an abrupt abort is better than a risky show of force. Ask your coach how to keep your hip in one line in uchi-komi. The best uchi-mata is the one where your standing leg feels calm.
Also use uchi-komi as conditioning: ten judoka performed blocks of 10, 20 or 30 seconds with equal rest, using o-uchi-gari, seoi-nage and harai-goshi; all structures produced oxygen and heart rate responses similar to a match simulation [6]. Uchi-mata was not included, but the principle can be transferred. Discuss the blocks with your coach.
Not as a first throw. The German Judo Federation assigns it to 5th kyu and requires it at 4th kyu [1]. O-goshi, o-soto-gari and the like come first.
Yes. The rules permit uchi-mata with an entwined leg and score it. Kawazu-gake, on the other hand, is forbidden [2].
In harai-goshi your leg sweeps the thigh from the outside, in uchi-mata it swings between Uke's legs and meets the inner thigh. Both demand the same base of hip and head position.
That is individual. Expect months. That is a practical rule of thumb, not a study.
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