Below I will explain each of the steps that make up the progression of the teaching-learning process of the side fall on the left (hidari yoko ukemi) in judo and aikido. You will always start from the simplest and easiest sequences, then progressively advance in the degree of complexity and finally reach full mastery.

Progression 1

• Starting position: In a left lateral decubitus position with the left leg extended and the right knee bent and placed on top of the other, and also with the chin pressed against the chest.
• Execution: Hit the ground with your left hand and forearm at a 35-degree angle.
• General mechanical principles:
  • Soften the force of the fall by hitting with your arms.
  • Optimal impact surface.

Progression 2

• Starting position: From a sitting position, with your legs extended and open, and your hands in contact with your thighs at knee level.
• Execution: Move the left foot towards the right foot (front and right) and roll backwards and to the left (back and left) with the chin tucked into the chest. The hands remain in contact with the thighs throughout the movement.
• General mechanical principles:
  • Soften the force of the fall by making a rolling movement, turning your back into a kind of wheel.

Progression 3

• Starting position: From a sitting position, with your legs extended and open, and your hands in contact with your thighs at knee level.
• Execution: Move the left foot towards the right foot (front and right) and roll backwards and to the left (back and left) with the chin against the chest, hitting the ground with the left arm at an angle of 35 degrees with respect to the trunk. We start with the left arm crossed at the height of the right shoulder. The moment of the hit is when the lumbar area of ​​the back makes contact with the ground when rolling.
• General mechanical principles:
  • Soften the force of the fall by hitting with your arms.
  • Optimal impact surface.
  • Optimal moment of impact.
  • Soften the force of the fall by making a rolling movement, turning your back into a kind of wheel.

Progression 4

• Starting position: From a squatting position.
• Execution: Roll backwards and to the left with your chin tucked into your chest. To do this, extend your left leg and bring it towards your right foot to direct your body in that direction. Your hands are in contact with your knees and remain in contact with your thighs throughout the entire movement.
• General mechanical principles:
  • Soften the force of the fall by making a rolling movement, turning your back into a kind of wheel.

Progression 5

• Starting position: From a squatting position.
• Execution: Roll backwards and to the left with your chin tucked into your chest. To do this, extend your left leg and bring it towards your right foot to direct your body in that direction, hitting the ground with your left arm at a 35-degree angle to your torso. Start with your left arm abducted at the height of your left shoulder. The moment of impact is when the lumbar area of ​​your back makes contact with the ground as you roll.
• General mechanical principles:
  • Soften the force of the fall by hitting with your arms.
  • Optimal impact surface.
  • Optimal moment of impact.
  • Soften the force of the fall by making a rolling movement, turning your back into a kind of wheel.

Progression 6

• Starting position: From a standing position.
• Execution: We crouch down into a squatting position and roll backwards and to the left with our chin touching the ground. To do this, we keep our left leg extended as we descend and move it towards our right foot so that we can direct our body in that direction. Our hands are in contact with our thighs and remain in contact with them throughout the movement.
• General mechanical principles:
  • Soften the force of the fall by making a rolling movement, turning your back into a kind of wheel.

Progression 7

• Starting position: From a standing position.
• Execution: We crouch down into a squatting position and roll backwards and to the left with our chin touching the ground. To do this, when descending, we keep our left leg extended and bring it towards our right foot in order to direct our body in that direction, hitting the ground with our left arm at a 35-degree angle to our torso. We start with our left arm abducted at the height of our left shoulder. The moment of impact is when the lumbar area of ​​our back makes contact with the ground when we roll.
• General mechanical principles:
  • Soften the force of the fall by hitting with your arms.
  • Optimal impact surface.
  • Optimal moment of impact.
  • Soften the force of the fall by making a rolling movement, turning your back into a kind of wheel.

Progression 8

• Starting position: With the help of a partner lying prone on the floor, we place ourselves on top of him in supine position with our knees bent and the soles of our feet supported, and we grab his belt from behind.
• Execution: We release our right hand from the belt and let ourselves fall to the right side, preparing ourselves with our right arm from the left shoulder to hit the ground at an angle of 35 degrees with respect to the torso. The fall must be from the upper body and not from the lower body, first contacting the upper back of the right half of the body.
• General mechanical principles:
  • Soften the force of the fall by hitting with your arms.
  • Optimal impact surface.
  • Optimal moment of impact.

Progression 9

• Starting position: With the help of a partner lying prone on the floor, we place ourselves on top of him in a supine position, raising both lower limbs with our knees extended, and we grab his belt from behind.
• Execution: We release our left hand from the belt and let ourselves fall to the left side, preparing ourselves with our left arm from the right shoulder to hit the ground at an angle of 35 degrees with respect to the torso. The fall must be from the upper body and not from the lower body, first contacting the upper back of the left half of the body.
• General mechanical principles:
  • Soften the force of the fall by hitting with your arms.
  • Optimal impact surface.
  • Optimal moment of impact.
  • Soften the force of the fall by making a rolling movement, turning your back into a kind of wheel.

Progression 10

• Starting position: With the help of a partner who is in a four-legged position on the ground and grouped together as if he were protecting himself, we place ourselves on top of him in a supine position with our feet flat on the ground and grab his belt from behind.
• Execution: We release our left hand from the belt and let ourselves fall to the left side, preparing ourselves with our left arm from the right shoulder to hit the ground at an angle of 35 degrees with respect to the torso. The fall must be first of all from the upper body. As we prepare to fall, the hand that is still holding the belt slides in the same direction as us.
• General mechanical principles:
  • Soften the force of the fall by hitting with your arms.
  • Optimal impact surface.
  • Optimal moment of impact.
  • Soften the force of the fall by making a rolling movement, turning your back into a kind of wheel.

Progression 11

• Starting position: With the help of a partner in a four-legged position on the ground and grouped together as if protecting himself, we place ourselves on top of him in a supine position, raising both lower limbs with our knees extended, and we grab his belt from behind.
• Execution: We release our left hand from the belt and let ourselves fall to the left side, preparing ourselves with our left arm from the right shoulder to hit the ground at an angle of 35 degrees with respect to the torso. The fall must be first of all from the upper body. As we prepare to fall, the hand that is still holding the belt slides in the same direction as us.
• General mechanical principles:
  • Soften the force of the fall by hitting with your arms.
  • Optimal impact surface.
  • Optimal moment of impact.
  • Soften the force of the fall by making a rolling movement, turning your back into a kind of wheel.

Bibliographic references:

• Taira, S. (2014). La esencia del judo (Tomo 1), 2ª edición. Satori.