Pain is a SIGNAL, not an enemy
A familiar scene: mid-session, a student stops short and winces: "Here… it hurts." In that one second a great many teachers fall into one of two WRONG reflexes:
- Reflex 1 — "Keep going, no pain no gain": pushing the student to grit their teeth through the pain → easily pushing them straight into injury.
- Reflex 2 — "If it hurts, stop altogether": ordering the student into complete rest → with chronic pain, the more they lie still the weaker and the sorer they get.
Both can harm a student. The problem is that we were never taught to READ what the pain is saying.
Reassurance before we begin: this lesson will NOT turn you into a doctor, and it does not ask you to memorise medical terms. It hands you a compass for reading pain signals safely — knowing when to carry on, when to modify, when to stop, and when a student must be sent to be examined. Start from exactly where you are.
The guiding line of the lesson: pain is the brain's alarm system, there to PROTECT you — not an enemy, and not a measuring stick for how damaged the tissue is. Learning to 'translate' that signal is the skill that closes Stage 2.
🎁 A gift from Tuấn Anh to teachers who want to master the craft.
What is pain, really?
The biggest idea of the lesson in one sentence: pain is made by the BRAIN to protect you; it is not a pin stuck in the sore spot.
Picture the body with a fire alarm system. Sensors in the skin, muscles and joints (called nociceptors) detect something out of the ordinary and send a signal to the spinal cord and the brain. But here is the crux:
- A signal is not pain. What is sent up is only raw data. It is the BRAIN that interprets it into the experience of 'pain', based on how much DANGER it judges there to be.
- Pain does not measure tissue damage. How much pain a person feels is not proportional to the damage visible on an X-ray or MRI. Some people have badly damaged tissue and little pain; others have healed tissue and still hurt severely.
- Pain is 'constructed' by the brain, but it is NOT imaginary. The pain is real — it simply does not live purely in the tissue.
Why does the same injury hurt one person a great deal and another barely at all? Because the brain decides according to context, emotion, memory, level of stress and fear as well. Pain is an assessment of danger, not an objective measurement.
What this gives you: when a student panics, "it hurts, something must be badly broken", you have grounds to reassure them: a great deal of pain does not mean a great deal of damage. This is the first reframe that defuses the panic, so they are calm enough for you to read the other signals.
Pain does not stand alone. It is one channel in the vast sensory network the body uses to 'report' to the brain — alongside position sense (ligament, tendon and muscle reporting continuously where a joint is and how taut a muscle is) and danger sense (which is 'pain'). In every joint capsule, the nociceptors belong to the same family as the sensors reporting angle, pressure and the limits of range.
In other words, pain is a normal information channel of the body, not a random enemy breaking in.
What this gives you: this is the physiological ground for "listen to your body". Pain and discomfort are an immediate statement to be listened to and adjusted for — not something to block out and push through, and not a reason to panic and flee.
Pain is the body's fire alarm. The trouble is that sometimes the alarm is too sensitive — shrieking away when nothing in the kitchen is burning at all.
Pain is a signal the brain constructs to protect you — it does not directly measure tissue damage.
ACUTE pain vs CHRONIC pain — two kinds, two opposite handlings
The line to keep in your pocket: ACUTE pain says "rest"; CHRONIC pain says "start moving again". Handle it the wrong way round and you harm the student.
Acute pain is new pain, usually under about three months, attached to a clear event: a sprain, a slip and a fall, a sudden overstretch of a muscle.
- The typical yoga example: kicking the leg forward, or forcing a split, without enough warm-up → the hamstring group is lengthened suddenly and the muscle fibres tear. This is tissue genuinely damaged.
- The body is repairing itself: scar tissue grows to knit the tear. Load that newly injured region hard and you spoil or slow the healing.
- The handling: give it TIME to heal — rest that region, avoid or modify the poses that load the painful area, and only then build back gradually.
What this gives you: with a fresh or acute injury, the reflex of "keep practising and you will get used to it" is wrong. You modify to avoid that region and give the student time; you do not push.
Chronic pain is pain lasting beyond the usual healing time (usually more than about three months) — a great many back-pain cases belong here.
- Its nature is entirely different: by now the tissue may be healed, or have very little actual damage left. The problem lies in an alarm system that has gone faulty and over-sensitive — the bell keeps ringing though nothing in the kitchen is burning.
- The handling is the OPPOSITE of acute pain: generally it needs no more rest; in practice the student usually needs MORE MOVEMENT, because safe exercise reduces chronic pain and the stress that comes with it.
- Why lying still does harm: avoiding movement → loss of fitness, weak muscles, stiff joints → the pain never resolves → and it hurts more. (Detail in Part 4.)
| Criterion | ACUTE pain | CHRONIC pain |
|---|---|---|
| Duration | New, usually < 3 months | Lasting > about 3 months |
| Tissue | Genuinely damaged | Usually healed / little damage |
| Nature | The alarm is CORRECT | The alarm is over-sensitive |
| Handling | REST / examination / modify and avoid | MOVE again, with control |
A note against complacency: 'chronic pain' does NOT mean the tissue is 100% healed. Some conditions (arthritis, for instance) still have an active process in the tissue. So moving again is the right direction, but you must still screen for red flags (Part 6) — do not assume that 'chronic means practise freely'.
What this gives you: do not mistakenly 'prescribe rest' for a chronic case (which weakens them further), and do not mistakenly 'push practice' on an acute one (which makes it worse). Asking about the timeline and how it started is the first step of classification.
The same word 'pain' covers two opposite things: ACUTE pain tells you to 'rest', CHRONIC pain tells you to 'start moving again' — treat one as the other and you do harm.
Acute = tissue being damaged → REST or get it examined. Chronic = an over-sensitive alarm → MOVE again, with control.
Good pain vs bad pain — the three-second test
This is the three-second test you can use mid-class. Every teacher's first question — is this "good pain to be borne" or "bad pain signalling injury"? — has a readable set of criteria:
| Signal | GREEN LIGHT · carry on | RED LIGHT · stop, come out |
|---|---|---|
| Location | Mid MUSCLE BELLY, even on both sides | At the JOINT, or SPREADING away |
| Sensation | A pulling stretch, warm, moderate | SHARP, STABBING, burning, electric, NUMB |
| Breath | Still even and smooth throughout | Having to HOLD THE BREATH / GRIMACE |
| How it develops | Eases as the pose is held | Grows worse the longer it is held |
Anchored by the knee: in deeply bent-knee seated poses, a strong stretching sensation in the muscle is normal, but pain in the knee joint is a DIFFERENT sensation — the knee is an unforgiving joint, and pain there means coming out IMMEDIATELY.
What this gives you: teach your students this very filter. The safe everyday phrase: "A stretch in the muscle and you can breathe — hold it; a twinge in the joint or you have to hold your breath — come out a little."
Turning the criteria into actions:
- In SLOWLY, try a little, then back off: enter the range gradually and stop at a comfortable stretch; do not charge straight to the maximum.
- The breath is the 'gauge' of effort: if the breath turns shallow and irregular, that is the sign of straining too hard and the body will grip; the session should be lighter. A smooth breath = still inside the safe zone.
- The threshold is INDIVIDUAL: in the same pose, what is 'too far' for one person is safe for another. Do not compare range with the person next door — follow each body's own signals.
The DOMS clock — handling the message "I'm sore after yesterday": delayed-onset muscle soreness (DOMS) is a normal adaptive response of muscle, not an injury: worst at 24–72 hours, resolving by itself within 5–7 days, felt as a dull ache spread evenly through the muscle belly.
- The warning flags, where it is no longer 'healthy soreness': pain lasting more than a week; pain in a joint rather than in the muscle belly; sharp or stabbing pain; or clear swelling and heat.
What this gives you: reply to a student's message on solid ground instead of guessing. An even ache for 1–3 days that then goes → reassure them, they can carry on with light practice. Joint pain, sharp pain, or more than a week → rest that region and consider referring them (Part 6).
(Note: the DOMS timeline is general exercise-physiology knowledge, used to orient your response — it is no substitute for examination when there are red flags.)
A three-second test for whether to carry on or stop: a warm stretch in the muscle belly, easing as you breathe → carry on; sharp, stabbing, numb, or joint pain → stop.
A warm stretch in the MIDDLE OF THE MUSCLE BELLY + a smooth breath = CARRY ON. Sharp, stabbing, numb, or JOINT pain + held breath and a grimace = STOP.
'No pain no gain' and 'if it hurts, lie still' — both are wrong
This line is both wrong and dangerous — and there is physical as well as neurological evidence against it.
- Yoga's founding principle is AHIMSA (non-harm) — walking beside medicine's oath to "first do no harm". The golden rule: avoid anything that causes pain or increases existing pain. The point of yoga is not a perfect asana.
- The physical ground (the stress–strain curve): in the elastic zone tissue stretches and returns to normal; past the yield point into the plastic zone, tissue does NOT recover; further still is complete rupture. A sharp pain in a stretch is not 'the joint about to open' — it is tissue about to leave the elastic zone.
- The neural mechanism that makes fast, forceful pushing backfire: the muscle spindle, pulled quickly, orders that very muscle to CONTRACT → bouncing or jerking in a stretch leaves you stiffer the next day, not more flexible.
- Forcing through pain = switching off the alarm that is warning you of danger. That is not progress; that is the recipe for an injury.
What this gives you: when a student asks "can I make progress without pain?", the answer is: results come from CONSISTENCY and CORRECT TECHNIQUE, not from enduring pain. Draw the line clearly: discomfort and stretch are normal; pain (above all sharp pain) is a signal to stop.
True for acute pain, but WRONG for chronic pain. With chronic pain, avoiding movement starts a vicious circle:
THE FEAR-AVOIDANCE SPIRAL:
- ① Fear of pain → not daring to move
- ② Little movement → weak muscles, stiff joints, pain never resolved
- ③ The brain feels pain more often → it gradually loses the ability to modulate the signal (the alarm grows more sensitive)
- ④ Physical and emotional health decline → back to ①, and it hurts more
A concrete anatomical example: someone with a rotator cuff tear usually does not want to move the arm. That immobility is what makes the scar tissue grow in a direction that maintains the immobility, forming adhesions → leading to a frozen shoulder. But if the injured region is moved even minimally, the new fibres grow in a direction that supports movement.
What this gives you: with a chronic-pain student avoiding every action, do not let them lie still. Draw them back into movement that is gentle, controlled and built up a little at a time, with reassuring language. Yoga's role in breaking that spiral is the subject of Part 5.
'No pain no gain' — the slogan millions believe is the studio's most dangerous misunderstanding, and physiology has refuted it.
Forcing through pain = ignoring the alarm → injury. Lying still with chronic pain = falling into the fear-avoidance spiral → growing weaker.
Yoga 'recalibrates' the alarm system — and rebuilds trust in the body
The aim is NOT to 'switch off' the alarm, but to teach the nervous system to tell real danger apart again. Chronic pain is largely a problem of regulation — a faulty alarm. Yoga does that through:
- Movement within capacity, repeated: every safe movement with no consequence is one more message to the brain that this movement is NOT dangerous → the alarm lowers its sensitivity.
- In slowly, held long, so the neural 'safety valve' opens: when a stretch is held gradually (usually 30 seconds or more), the sensory nervous system raises its tolerance to stretch and so lets the muscle release (partly through the Golgi tendon organ), and the sensors recalibrate to the new length — the stretch becomes effective and comfortable. This is 'talking' to the nervous system, not crude mechanical forcing.
- Measurable pain relief: there is evidence that yoga reduces chronic back pain to a clinically meaningful degree; one yoga programme even helped reduce the need for painkillers. Moving a joint through a wide range also 'pumps' the fluid that keeps cartilage healthy.
What this gives you: locate your own role correctly — you are the person who organises safe return to movement, not the person who 'cures' pain. Raise the dose a little at a time, hold poses long enough, go in slowly.
Pain is amplified by fear and by stress — and yoga works on that side too.
- The breath changes the neural state: slow, deep diaphragmatic breathing helps the body shift from alarm (sympathetic) to safety (parasympathetic) — less on guard, and the pain threshold lowered in sensitivity.
- The brain can RELEARN: on the basis of neuroplasticity, repeatedly attending to the breath and to neutral sensation gradually helps the nervous system over-react less to the signal — a mechanism with real grounding, not 'imagine the pain away'.
- Cutting the fear–pain loop: when a student experiences that they can still move, safely, they rebuild their trust in their own body — the single most important link in escaping the spiral.
What the teacher does concretely: use reassuring, inviting language ("soften", "bend a little", "be kind to your knee") rather than forcing anything locked; modify poses to capacity, using props (blocks, straps, a chair, the wall) for support; ask for feedback continuously, and always ask permission before touching.
What this gives you: you become the 'translator' of the signals and a safe companion, helping a student trust their own body again — rather than governing by fear or by "come on, push".
Yoga's real role is not to 'kill' the pain but to use safe movement to teach the alarm system that the body is still safe — and to rebuild trust.
The aim is not to 'kill' pain, but to reteach the nervous system that this movement is safe.
When a teacher MUST let go and refer to a doctor
A teacher does NOT diagnose. On seeing any of the signs below, do not go on adjusting the pose yourself — refer the student to a medical professional:
- Pain SPREADING or STABBING down a limb (a sharp or electric sensation running down an arm or a leg).
- NUMBNESS in a limb (lost or reduced sensation).
- WEAKNESS or PARALYSIS, or loss of control; above all, disturbance of bladder or bowel, which is an emergency.
- Pain AT NIGHT, pain unrelated to position, or pain with unexplained weight loss.
- Pain immediately AFTER A SERIOUS INJURY (a fall, an accident); and after surgery, the surgeon must be asked.
- Severe pain that is getting worse over time.
The golden rule: "Always ask the professional medical team; if in doubt, refer." The causes of pain and compression are many and varied (disc degeneration, bone spurs, arthritis, muscular disorders, injury) → they need a qualified person to diagnose, not a teacher.
What this gives you: this is the professional boundary that protects your student and protects you in terms of liability. Print this list out and learn it by heart. Never keep a case beyond your competence.
The key distinction: localised muscle pain stays within the muscle belly; nerve compression or referred nerve pain spreads along the line of a nerve.
- Sciatica: pain spreading along from the spine down the BACK of the thigh and on down the leg.
- A rounded, hunched neck and shoulder: the neck and shoulder posture compresses the brachial plexus → pain and numbness referred down the arm.
- Beware the blind spot: no local pain ≠ safe. A mechanical disorder can produce no localised pain while dumping load on another joint. Read the alignment and the movement as a whole, not only the painful point.
A note on stretching near a nerve: a sensation of numbness, burning or electricity running down a limb during a stretch is NOT 'about to get more flexible' — it is a trapped nerve under tension, and you must stop at once.
What this gives you: when a student describes pain that 'runs' along a line down the arm or the leg (not a stretch in the muscle), treat it as a neurological signal — be cautious, do not force a stretch into that region, and refer them if it persists.
There are signs that mean a teacher must let go at once and point the way to a doctor: pain and numbness spreading down a limb, weakness or paralysis, pain at night, pain after an injury.
Spreading pain or numbness, weakness or paralysis, pain at night, pain after a serious injury → do NOT handle it with asana. If in doubt, refer.
You are the 'translator' of signals, not the one who forces people through pain
Before teaching a student, feel the difference in yourself.
- Come into a gentle forward fold. Find the sensation of a warm stretch in the middle of the hamstring belly — breathe evenly, hold, and notice it easing. That is the green light.
- Compare it with the sensation near the knee or the hip joint when you push too far — sharp, pinching, making you want to hold your breath. That is the red light; come out at once.
- Notice the breath at each level: when it turns shallow or you hold it, that is the body telling you it is enough.
The aim: to record in your own body the difference between 'a muscular stretch' and 'joint pain', so you recognise it instantly when watching a student.
- Situation 1: a student writes "both hamstrings have been achy since yesterday, evenly on both sides, better today". → Decision: CARRY ON. This is DOMS (peaking at 24–72 hours, gone within 5–7 days). Reassure them; gentle normal practice is fine.
- Situation 2: mid-class, a student feels a twinge in the knee on bending deeply and has to hold their breath. → Decision: STOP + MODIFY. Come out of the range, support with props, keep the joint in a pain-free zone. Joint pain is an unforgiving boundary.
- Situation 3: a student with back pain mentions that sometimes numbness and a stabbing pain run down the calf, and it occasionally hurts at night. → Decision: REFER TO A DOCTOR. These are neurological red flags; a teacher does not handle them with asana — refer them to a medical professional first.
Bonus — the chronic-pain student who avoids movement: a student with back pain for more than 6 months, already examined with no serious damage found, afraid and avoiding everything. → Do not let them lie still; bring them back into gentle, controlled movement, built up gradually, with the breath and with reassuring language.
See one of the following → stop handling it and refer to a doctor:
- ☐ Pain spreading or stabbing down an arm or a leg
- ☐ Numbness or loss of sensation in a limb
- ☐ Weakness or paralysis, or disturbance of bladder or bowel (an emergency)
- ☐ Pain at night / unrelated to position / with weight loss
- ☐ Pain immediately after a serious injury, or after surgery
- ☐ Severe pain getting worse over time
The golden rule that closes the lesson: a teacher does not diagnose and does not keep a case beyond their competence — if in doubt, refer. That is the mark of a good and responsible teacher, not a weakness.
The more you fear pain and avoid movement, the weaker and the sorer you become — the silent trap called 'fear-avoidance' holds a great many people with back pain captive.
Pain is a companion bringing news. The teacher's job is to read it correctly and act correctly: carry on / modify / stop / refer.
You now have a compass for reading pain signals — knowing when to carry on, modify, stop or refer. But this is still reading the signal. The big question of Stage 3 is: once you know which region is safe, how do you design a session that suits each person, raising the dose correctly so the body grows stronger without tripping the alarm? We step from 'translating a body' to 'architect of safety'. See you in the next lesson.
To unlock Lesson 9
Answer all three correctly to unlock Lesson 9.
1. What are the four walls of the “core canister”?
2. On the IN-BREATH, how do the diaphragm and the pelvic floor move?
3. Engaging the core PROPERLY means:
The road — 31 lessons · 4 stages
You are on Lesson 8. Each lesson opens one real question about the body — understand it, and you practise & teach that much more soundly.
- 1The spine — the axis of all movementAvailable
- 2The six directions the spine movesAvailable
- 3Which muscles each spinal direction uses (SHORTENING ↔ LENGTHENING)Available
- 4Why years of practice still won't get you into the lotus (tension vs compression)Available
- 5Every joint its own kind of hinge (bone – joint – cartilage – ligament)Available
- 6Muscle, tendon, fascia: the factory that makes & transmits forceAvailable
- 7Does stretching really make a muscle "longer"?Available
- 8The core is an "inflatable corset" — breath · diaphragm · pelvic floorAvailable
- 9One shape at the foot frees the shoulder (fascia)Available
- 10Why one cue produces a different shape in every bodyAvailable
- 11Reading the body as a system of forces (putting it together)Available
Which statement describes the nature of pain CORRECTLY?