Parighāsana (see Light on Yoga, plate 39), comes after the standing poses (No. 15 in the book). This pose stretches the sides of the body, and as such, prepares for more advanced āsanas, including twists and backbends.
Although its level of difficulty in Light on Yoga is 4, it presents many challenges. Working on the preparations included in this class will teach you to open the body laterally while extending the sides of the trunk and the back of the legs. These preparations will help you to continue on to the more challenging poses in the following classes of this course.