At the most basic level, asana is used to shift the balance between the sympathetic nervous system (fight or flight response) to the parasympathetic nervous system (relaxation response). It also strengthens immunity and fights off stressors leading to better physical and mental health.
In Kundalini Yoga, there are various aspects that make up the practice. Asana is a Sanskrit term for "pose" or "posture"—the movements or postures of the body we so commonly associate with yoga today.
Examples of commonly known asanas include downward dog, child's pose, seated poses, and forward bends. These are used in Kundalini Yoga in addition to more specific and unique asanas, such as spinal flex, life nerve stretch, cat-cow, and spinal twist. In conjunction with the other aspects of a Kundalini Yoga practice, the goal of these asanas is to create a desired and specific effects, such as enhancing organ function or opening meridian pathways.
The asanas in Kundalini Yoga may look and feel strange at first, but once you keep doing it and pour yourself into the practice, you'll begin to notice profound shifts in your life.