I’ve always been intrigued by the human body and wanted to learn about it. Recently, I’ve been enjoying studying an anatomy and physiology course again. This is the 3rd one I’ve done over the years, but the first time on-line.
We’re so fortunate these days to be able to study with video lectures, monographs, articles, textbooks, and so on – no farther away than a click of a mouse. Much better than sitting in draughty lecture halls with sometimes boring tutors.
I’ve been fascinated by the physical demonstrations from the Applied Anatomy and Physiology with Simon Borg-Olivier of Yoga Synergy, because he appears to have such complete and easy command of his body. He can isolate muscles to show minute movements of joints or put himself into yoga postures to explain how his anatomy principles create best practices.
Simon seems to have a good grasp of Sutra II-47, in the way that commentator B.K.S. Iyengar sets it out:

The sadhaka (a person on the yoga path) can be considered firm in his postures when persevering effort is no longer needed. In this stability, he grasps the physiology of each asana and penetrates within, reaching the minutest parts of the body. Then he gains the art of relaxation, maintaining the firmness and extension of the body and consciousness. In this way he develops a sensitive mind. With this sensitivity, he trains his thinking faculty to ready, study and penetrate the infinite.
Prayatna-saithilya-ananta samapattibhyam

Perfection in an asana is achieved when the effort to perform it becomes effortless and the infinite being within is reached.*
*Light on the Yoga Sutras of Patanjali, B.K.S. Iyengar.