Learn okuri-ashi-harai in judo: uke's sideways movement, timing as the feet close together, sweeping instead of kicking. With milestones and safety rules.
The honest answer: okuri-ashi-harai is a foot sweep. You sweep both of uke's feet away to the side while he moves sideways, and let him fall in the same direction with your hands. "Okuri" means to send along, "ashi" foot, "harai" sweep. The German Judo Federation (DJB) lists it (as okuri-ashi-barai) in the extended programme of foot techniques, so the material from 3rd to 1st kyu [1]. That is why it is intermediate. The prerequisite is de-ashi-harai, which you know from the basic programme.
What makes it hard? The timing. You do not sweep at some point, but in the short moment when uke's feet come together during a side step. Come too early and you hit air, come too late and you hit feet that are already standing again. In addition, the throwing effect comes from pull and foot sweep together, not from a hard kick.
Under the rules, an ippon is given only for a controlled fall with speed and force [2]. Expect several weeks of practice until the timing sits, and considerably longer until use in free fighting (practical estimate, not a study).
You walk sideways together: uke takes closing steps, you follow. You stay in the grip (sleeve and lapel). Milestone: you walk ten steps sideways without losing your balance.
Your hands lead uke on in his direction of movement, as if inviting him to come along. A learning study on kuzushi (balance breaking) suggests that uchikomi with built-in kuzushi helps with pulling and pushing (a study with 64 children on o-soto-gari, so TRANSFER; group differences not significant) [3]. Milestone: uke walks on willingly because you take him along.
Wait until uke's feet come together in the closing step. At that instant his weight lies briefly on both feet and cannot dodge. Your standing foot is close to his body. Milestone: in uchikomi (entry without a throw) you recognise the moment in eight of ten steps.
Your other foot sweeps flat over the mat, the sole meets uke's ankles from the side and pushes both feet away. You sweep, you do not kick. Milestone: in slow motion the sole touches both ankles without uke tripping.
The hands pull uke on in the same direction until he lands on his side. You stay upright. Only with your instructor's release do you really throw. Milestone: uke lands on his side in control.
In a foot sweep uke's ankle is the target, and that is the most sensitive spot. A survey of 4659 judoka found that injuries with more than three weeks of time loss affected the upper limbs (arms, shoulders) in 41 % and the lower limbs in 39 % [5]. That applies to judo as a whole, not to okuri-ashi-harai, but shows how important it is to protect the legs.
In practice: you sweep with the sole, not with the edge or heel. Practise uchikomi first, then a slow sweep without the pull, then the throw. Uke must master ukemi reliably: an overview of 16 studies shows that clean break-falling keeps the head load below the injury threshold [4]. At the first throw your instructor stands beside you and can intervene.
This guide explains and motivates; it does not replace supervised training.
Imagine you are sweeping dust from a floor you do not want to damage. The movement is a long swing, not a thrust. With the pulling hand you lead, with the foot you accompany. If your foot audibly slaps, it was a kick.
How to fit it into your week: practise uchikomi twice a week for five minutes with a partner who walks sideways in a circle. Ten repetitions per side, always watching the timing, not the force. After three clean sessions you talk to your instructor about the first controlled throw. This is practical experience, not a study.
In de-ashi-harai you sweep the front foot that is just landing. In okuri-ashi-harai you sweep both feet together during the side step, in uke's direction of movement. The DJB lists okuri-ashi-barai in the extended programme and de-ashi-barai in the basic programme [1].
The DJB lists it in the extended programme for 3rd to 1st kyu [1]. Your club may start earlier, for example in exercises on foot techniques. What matters is that de-ashi-harai sits.
The timing is the challenge. Expect several weeks for a secure feel in uchikomi. This is a practical estimate, not a study.
With a clean sweep with the sole and secure ukemi the risk is small. A kick against the ankle, on the other hand, can injure. Practise with an instructor and build up slowly.
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