Shifting the center of mass closer to the center of the stance, adds stability to the front leg. Although this may be desirable at times, a main advantage of the back stance is the stability of the back leg. With the weight forward, the stability of the back leg is diminished. When the feet are situated closer to each other, mobility may be enhanced. With the feet angled out further, movement to directions outside a 90-degree range become more easily attainable.
When the left leg is forward, the stance a left back stance. When the right leg is forward, it is a right back stance.
Stand with feet parallel, 1 shoulder width apart. Step left foot forward 1/2 shoulder width deep into a back stance with the heel aligned with rear foot's heel. Imagine an "L" shape drawn on the floor. The right foot will align with the bottom of the "L" with the heel at the corner and the front foot will align along the long side of the "L."
The shoulders angle 45 degrees toward the right. Keep hips parallel with the shoulders so upper body is angled toward the right. Narrow profile and strongly turned hips limit an opponent's direct access to body targets. The hips are pulled back 45 degrees from forward facing. Any more seriously restricts movement and power in techniques. Do not pull the trailing shoulder back too far because it opens you to counter attack and delays response time.
Keep body erect; do not hunch the shoulders.
Front foot is pointed toward the opponent.
Bend the front leg at the knee, with the shin vertical. Front foot merely rests on the floor.
Distance between feet varies between styles. Longer stances allow you to pull back further whereas shorter stances permit faster movement. Longer stances curtail quick movements while short stances prevent you from bracing effectively in the face of a determined attack.\
Rear leg is bent so 70 % of the weight is on the back foot (hence the name back stance) and 30 percent of the weight is on the front foot.
The center of mass is centered nearly over the rear foot. The weight is settled mostly over the rear leg.
Back stance cannot effectively resist off balancing forces, due to its uneven weight distribution and narrow base. A good push from the front will cause the lead foot to rise from the floor. This may be minimized by keeping at least 25% of the body weight over the lead foot. The stance is also weak against lateral forces.
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