The pose that harms shoulders most is the one you teach every session

Chaturanga Dandasana (the low push-up) appears in every vinyasa, in every transition between poses. One Power or Vinyasa session repeats it 10–30 times; across hundreds of sessions that is tens of thousands of times.

• The paradox: a 'low dose' pose repeated an enormous number of times produces cumulative micro-trauma — wearing down gradually rather than tearing suddenly.
• The key mechanical mechanism: in the sequence from high Plank into Chaturanga, pectoralis major must contract in EVERY phase — holding (isometric) → lowering (ECCENTRIC contraction, where the muscle lengthens while still gripping, under great load) → pressing up (concentric). It is that repeated eccentric contraction under load which is the context most likely to overload the shoulder tissues.
• The anatomy texts recommend it directly: with a shoulder or a rotator cuff that is already troubled, one should AVOID low Plank (Chaturanga), above all in the acute phase, and prioritise strengthening over stretching — which is enough to show this is a pose to be wary of while the shoulder is not ready.

What this gives you: do not examine the technique once and stop there — examine the FREQUENCY in your lesson plan. Reducing the number of Chaturangas per session is a genuine protective measure, not 'watering the class down'.

That line is half true and half dangerous.

• The forgotten truth: even with correct technique, it is the number of repetitions that is the variable. A bridge carrying exactly its rated load still suffers metal fatigue after enough cycles.
• The highest-risk group is NOT beginners — it is long-serving teachers and dedicated practitioners, because they repeat it most.
• Yoga anatomists go further: understanding the shoulder mechanism properly would take Chaturanga off the list of 'the riskiest yoga poses' — meaning the problem lies in how it is used, not in the pose itself.

What this gives you: the answer to the profession's biggest question — 'should Chaturanga be dropped altogether?' The answer: no need to drop it; reduce the frequency, teach the mechanism correctly, and build enough foundational strength.

When a student lowers incorrectly, the damage unfolds in a mechanical sequence:

1. The shoulder blade loses its anchor: serratus anterior fails to hold, the inner border of the blade lifts away from the back (a 'winged scapula') → the stable BASE is lost.
2. The head of the upper arm bone loses its centre: with the base gone, the rotator cuff muscles can no longer hold the head centred in that shallow socket → the head shifts within the socket.
3. The rotator cuff tendon is pinched: the supraspinatus tendon, threading through the NARROW space beneath the acromion, is compressed between the greater tubercle and the acromion — called shoulder impingement.
4. The front of the joint capsule is overloaded: the shoulder 'drops' below the level of the elbow, and the weight falls passively on to the capsule and the ligaments at the front instead of into the muscle.

What this gives you: remember this chain to explain to a student WHY it hurts — and to know which link each correction blocks (anchor the blade, hold the elbow, stop at 90 degrees).

The job of serratus anterior is to press and hold the shoulder blade against the ribcage. When it is weak:

• The INNER border of the blade lifts and juts away from the back as the student lowers or presses up — that is a 'winged scapula'.
• The stable base is lost → all the load in a weight-bearing arm position falls wrongly on to the shoulder joint instead of being distributed through the shoulder girdle.
• Because Chaturanga is repeated hundreds of times, a weak serratus anterior repeating this fault → accumulates damage.

Myth-busting: many people think the problem is 'a lack of strength'. More precisely: it is a lack of shoulder-blade STABILITY (serratus anterior + rotator cuff) that is the crux.

What this gives you: watch the inner border of a student's shoulder blade as they lower — if it wings, that is the signal to stop and build the base before letting them into a flow.

Turning the knowledge into a visual checklist — scan a whole class in seconds:

• 1. The shoulder DROPS lower than the elbow (the shoulder 'falling' past elbow level): this is the commonest cause of shoulder pain. The shoulder must be LEVEL with or higher than the elbow, never lower.
• 2. The elbows flare outward (splayed like a military push-up): a direct route to shoulder impingement. The elbows must point backwards, hugging the ribs.
• 3. The chest sagging towards the floor + a rounded upper back: the sign of over-using the 'pushing' group, with the shoulders falling forward.
• 4. The neck retracted / the shoulders hitched to the ears: over-using the upper trapezius, and losing shoulder girdle stability.

What this gives you: print this checklist in your head. With a large class you cannot examine each person — but these four signs are obvious enough to catch from a distance and address with a general cue.

The commonest alignment fault: placing the hands too far FORWARD — the hands under the SHOULDER rather than under the ELBOW — and then letting the shoulders drop.

• Yogis instinctively put the hands forward, on the reflex that 'nobody wants to land face-down on the floor'.
• The consequence: the body 'hangs on the shoulders' — releasing the stabilising muscles so the weight falls passively on to the capsule and the ligaments at the front. Exactly the mechanism of overload.
• The same fault appears in Upward Dog — when the shoulders fall forward and the chest slides past the hands.

The correct position, for comparison: the elbows bent to 90 degrees, the wrists directly under the elbows (not under the shoulders), the shoulders held level with the elbows. Entering from Plank, you must bring the chest forward a few centimetres before lowering.

What this gives you: this is the 'root' of all four red lights above. Correct the hand position and you correct most of the rest.

Build a ladder of progression so every level has a rung that fits:

• Rung 1 — Knees down (half Chaturanga): knees to the floor, reducing the load, practising keeping the elbows against the ribs and the blade anchored.
• Rung 2 — Halfway, with props: rest the chest and pelvis on a bolster, or press the feet into a wall, to feel the alignment before lifting their own weight.
• Rung 3 — A strap around the upper arms: blocks the elbows flaring once the student tires.
• Rung 4 — Full Chaturanga, only once the foundational strength is there.

An important principle: do not assume that any variation is automatically 'safer' for a beginner. Every rung still demands holding the shoulder blade stable and the elbows against the ribs; let go of the base and the shoulder falls forward in any variation at all. The clearest and most controllable way to reduce the load is knees down while keeping the Chaturanga alignment exactly — not switching to a different shape and trusting that it is safe in itself.

What this gives you: with this route you can individualise for a group class while still holding one common standard.

Alignment only holds if the student has the muscle to hold it. For the shoulder, prioritise strengthening over stretching:

• Serratus anterior: holding a plank with 'press the floor away' (protraction), training the blade to support.
• The posterior group that holds the shoulder back: rhomboids, middle and lower trapezius, posterior deltoid, infraspinatus and teres minor — to rebalance the 'pushing' group at the front and stop the shoulder falling forward.
• With a shoulder already troubled, or a history of dislocation: prefer holding Plank and Downward Dog on the FOREARMS, on the floor or at a wall, and avoid low Plank in the acute phase.

Why not to over-use shoulder stretching: ligament and tendon are almost INELASTIC — forcing a shoulder stretch to an extreme repeatedly can leave the capsule lax, turning a loose shoulder into a chronic one. 'Stretch muscle; do not stretch tendon.'

What this gives you: the answer to the foundational question — it is not enough to correct the cue; you must build shoulder blade and rotator cuff stability alongside it.

To support the upper body we use the 'pushing' group: serratus anterior + pectoralis major. The risk: over-use → the shoulder too far forward, the upper back rounded.

• The key antagonist pair: serratus anterior ⇄ rhomboids govern the position of the shoulder blade. In Chaturanga the serratus must prevail to prevent winging, BUT it must be balanced by the rhomboids so the shoulder does not fall forward.
• Chest-opening counterposes: Cow Face (Gomukhasana) moves and safely stretches all three parts of the deltoid; gentle chest openers release pectoralis major and minor, commonly gripped by a life spent with the arms folded forward.
• Reinforcing the rotator cuff: external rotation work against light resistance (a band) builds infraspinatus and teres minor — the group that protects the joint from impingement.

What this gives you: after a session heavy with Chaturangas, slot in two or three of these counterposes to 'give the balance back' to your students' shoulders.

Four short instructions, tied to the right mechanism, for a group class:

• 'Hands under the elbows, not under the shoulders' — blocks the hands-too-far-forward fault.
• 'Elbows hugging the ribs, pointing back' — blocks the flare and the impingement.
• 'Stop at 90 degrees — shoulders level with the elbows; never let the shoulder drop below the elbow' — blocks lowering too far.
• 'Shoulders sliding away from the ears, chest reaching forward' — lowers the shoulder girdle using the middle and lower trapezius, rather than hitching the shoulders up.

An important nuance (do not teach it rigidly): 'take the shoulders away from the ears' does NOT mean pressing the blades down as far as they will go — pressing down too hard also impinges the shoulder girdle. And no dogmatic cue is correct for every shoulder structure; observe and adjust for each person.

What this gives you: this is your 'read it in class' set — learn it by heart so you need not think while the class is moving.