3rd Limb · Bahiraṅga
The Seat — steady, and at ease.
Root: √ās — “to sit, to be seated.” Literally the seat; the posture from which everything inward is undertaken.
What is Āsana
Three sūtras, and the whole of the posture
Of all eight limbs, Patañjali gives Āsana the least text — just three sūtras. The first defines it completely: sthira-sukham āsanam, a posture that is at once steady and at ease. Not strength for its own sake, not flexibility for display — the meeting point of the two, where the body can be still without strain.
The two that follow tell you how it is reached and what it yields. YS II.47: prayatna-śaithilya-ananta-samāpattibhyām — by the relaxation of effort and absorption in the infinite. And YS II.48: tato dvandva-anabhighātaḥ — thereafter, one is no longer buffeted by the pairs of opposites: heat and cold, gain and loss, praise and blame.
In the tree, Āsana is the trunk: it must be upright and rooted, but its purpose is not to be admired — it is to free the sap to rise, into the invisible work of the inner limbs above.
The Primary Series, in 3D
A real yogi, driven by motion-capture
Below is a live, inspectable 3D figure — a 10,475-vertex anatomical body model — performing the Ashtanga Primary Series. The motion is not animation: it is real academic motion-capture (the MOYO dataset), so the joint angles and the natural balance-seeking sway are those of an actual practitioner. Drag to orbit, scroll to zoom, and step through the sequence.
Heads-up: each pose streams a large capture file, so give it a moment on a slower connection.
In the Ashtanga Tradition
The Primary Series — Yoga Chikitsa
In the Ashtanga Vinyāsa lineage of Krishnamacharya and Pattabhi Jois, Āsana is met not as isolated postures but as set sequences — the Primary Series, Yoga Chikitsa (“yoga therapy”), being the first. Each posture is entered and left through vinyāsa: a counted, breath-linked bridge of movement, so the practice becomes one continuous thread rather than a series of stops.
Three things hold attention throughout — tristhāna: the breath (Ujjāyī), the bandhas, and the dṛṣṭi (gaze). In a Mysore room the sequence is memorised and self-paced, so the posture work is already quietly training the limbs that follow: breath regulation, sense-withdrawal, and one-pointed concentration.
Practising It
Where am I gripping that I don't need to?
The instruction hidden in sthira-sukham is a question you can bring to any posture: where am I gripping that I don't need to? Find the steadiness first, then look for the ease inside it — soften the effort that isn't load-bearing, let the breath stay long and even, give the eyes one place to rest. When a shape stops demanding attention through discomfort, it has become an āsana.