Learn the underhook in wrestling: arm under the armpit, elbow tight, take the angle. With shoulder protection, UWW rules and clear milestones for beginners.
The honest answer: an underhook is a grip in which your arm slides under your partner's armpit and controls their torso before they control yours. It is the basis of throws, body control and takedown preparation. Whoever wins the underhook usually wins hand fighting.
UWW rules describe active wrestling in Greco-Roman style as seeking contact, hooking each other and preparing an attack. Someone who only blocks and prevents the opponent from wrestling can be called passive [1]. So your underhook is not only a grip but also a sign of activity.
And it has a price you should know: the shoulder. Among wrestlers shoulder and elbow injuries together make up 21.2 % of all injuries [2]. That is roughly every fifth injury. So you learn the underhook shoulder-friendly.
Your elbows are inside, your partner's outside. From inside you slip under their armpit easily, from outside you have to go around their arms. Milestone: you win inside position 5 times in a row against a partner who only stands still.
The palm faces the back, the arm slides under the armpit until the hand rests on the shoulder blade or lat. Interlocking fingers to block the partner are prohibited under UWW rules [1]. Your grip is open and active, not closed.
The elbow stays close to your ribs, the shoulder goes up. Your head lies beside your partner's head. Imagine your arm is a hook that fastens your partner to your body. Do not pull with the hand but with the whole upper body.
You step out with the foot on the underhook side. Your hips then stand sideways, not frontal to the partner. Sideways is stable, frontal is a target. Milestone: you hold the position for 30 seconds against light resistance without your partner freeing the arm.
The underhook is an intermediate goal. From here you go to over-under, arm drag or body lock, each with a coach. The opponent usually answers with an overhook. That is the whizzer, which you learn yourself later.
A common result is the over-under: you have the underhook on one side, your partner on the other. Then the fight is decided by head position and hips, not strength. Calm breathing helps here: whoever holds their breath tenses the shoulder, and a tense shoulder loses the hook. That is practical experience, not a study. Also expect your partner to seek their stronger side. Deliberately practice on your weaker side too, or it stays weak.
Practice in three stages: cooperative, light resistance, then live. Move on only once you manage the first stage cleanly 3 times.
Hand fighting looks harmless but loads the shoulder heavily. Among high school wrestlers shoulder and clavicle made up 21.0 % of injuries in competitions [3]. In a season study shoulder (24 %) and knee (17 %) were the most frequently affected areas [4]. A review names rotator cuff, acromioclavicular joint and instability as the most common shoulder injuries [2].
Dose the pressure, especially against lighter or new partners. Release the position at the first twinge, not at the crack. Skin counts too: in herpes outbreaks the location of the lesions even reflected the wrestlers' handedness [5]. That means skin working against skin also carries infections along. This does not replace supervised training: learn the underhook with a coach.
Do not ask how you get the arm under the armpit but where your head is. If your head lies beside your partner's head, they have no room for an overhook. Your head closes the space your arm opened.
A grip in which you slide an arm under your partner's armpit to control their torso and shoulder. It is the basis for body lock, arm drag and many throws.
In an underhook your arm slides under your partner's arm, in an overhook (whizzer) over the arm. The overhook is the typical answer to an underhook.
It loads it if the arm gets into extreme rotation under pull. Shoulder injuries are common in wrestling [2]. With a warm-up, dosing and a coach the risk stays manageable.
When you hold the position for 30 seconds against light resistance and your coach clears it. The body lock is safety-critical and comes only after that.
Arm Drag in Wrestling: Pulling the Arm Across and Getting Behind