“Can these four Yoga Aṅga – Yama, Niyama, Āsana, Prāṇāyāma
– be practiced by everyone at every stage of life?
How often and how long should one practice?
How can we adapt our practice to changing circumstances?
These questions and others like them must be answered by a competent teacher,
according to each student’s individual circumstances.”
– T Krishnamacharya’s commentary to Yoga Sūtra Chapter One verse 30