Revision 7T · Full Tutorial Edition · Updated 1 September 2026
PWR-048 · SUPERVISED full tutorial
Train one measured signal, then check whether learning survives without the display
Biofeedback can make selected body signals trainable; every claim belongs to a particular person–sensor–feedback–task system. Closed-loop biofeedback shows a measured body signal and lets Jo test one response strategy. Jo's EMG therapist selects a valid sensor, target and dose; Jo calibrates, practises in short blocks, names artefacts and tests a hidden-feedback block. A display change is not automatically a health change. In Jo's surface-EMG fixture, Jo learns the visual signature of quiet muscle activity, purposeful contraction and cable-motion artefact before trying to lower unnecessary shoulder recruitment during a reach.
What you will produceIn a qualified session, Jo completes baseline, feedback, correction and display-hidden blocks for one declared signal with artefacts and symptoms recorded.
Method10 numbered Power-specific steps
Practice authorityFull method with qualified supervision where stated
Full step-by-step individual tutorial · TLU-PWR-048
In a qualified session, Jo completes baseline, feedback, correction and display-hidden blocks for one declared signal with artefacts and symptoms recorded.
Classify the clinician-recorded quiet-muscle, gentle-contraction and cable-motion traces before using the display during a supported foam-puck reach.
Try the therapist-selected shoulder-release cue on matched visible-feedback reaches and then repeat one reach with the display hidden.
Report reach phases, EMG artefacts, task quality, discomfort and assistance without equating a low graph with better function.
Qualified help is required for
Selecting the muscle/site, preparing skin, placing electrodes, checking impedance/signal quality and distinguishing movement artefact from muscle activity.
Choosing the supported reach, cue, display scale, interval count, rest, symptom stops and whether feedback is clinically appropriate.
Interpreting EMG change, altering rehabilitation load or using therapeutic electrical/biofeedback equipment beyond this recorded session.
Never do this from the page alone
Move an electrode, change gain/filtering or tug a lead during a scored comparison to make the trace look quieter.
Brace, hold the breath or sacrifice the puck reach merely to drive the displayed line downward.
Use surface EMG to diagnose a condition or change treatment, medication, load or device settings without the responsible clinician.
2 · Get ready
Gather what you need and check the starting conditions
What you need
One provider-approved sensor system for a single signal, such as surface EMG, peripheral temperature or respiratory rate.
Manufacturer instructions and a calibration or signal-quality check.
A supportive task position and provider-set timer.
A block record for raw signal summary, cue, artefact, symptom, feedback state and functional outcome.
Before you start
Name the single signal, target direction and reason for training; do not mix several displays into one score.
The provider checks contraindications, skin, device integrity, privacy and whether the signal has a clinically meaningful use.
Agree one low-effort strategy and one stop rule before the baseline.
Keep medication, prescribed devices and ordinary supports unchanged.
3 · The method
Follow these steps in order
Name the loop
Say what the surface electrodes measure, how EMG display represents it, what action you will try and what outcome matters beyond EMG display.
Why: A clear person-sensor-feedback-task loop prevents vague “body control” claims.
Check: Jo can point to each link and name the measurement unit.
Check signal quality
Jo's EMG therapist places surface electrodes, follows EMG unit check and asks Jo to make a known small action to confirm that EMG display responds as expected.
Why: Poor contact, motion and electrical noise can masquerade as physiology.
Check: EMG trace is stable at rest and changes appropriately during the check.
Capture a quiet baseline
Complete a therapist-timed EMG interval without using shoulder-release cue. Record posture, support, signal and artefacts.
Why: A baseline shows drift and normal variation before feedback learning.
Check: The raw baseline remains visible and is not discarded for looking untidy.
Apply one strategy
Use only the agreed action, such as releasing a selected muscle or making an easy breathing change, during the feedback block.
Why: Changing several things at once hides which action affected EMG waveform.
Check: Shoulder-release cue is observable and stays within comfortable effort.
Read trends, not flicker
Watch the therapist-selected EMG trend and ignore isolated spikes. Pause when movement, speech or sensor contact creates an artefact.
Why: Closed-loop learning depends on valid feedback, not chasing noise.
Check: Artefact periods are marked and excluded under the predeclared rule.
Correct one error
Use the EMG therapist’s feedback to change one feature—posture, effort, cue timing or sensor contact—and repeat a matched block.
Why: One controlled correction makes cause and effect easier to interpret.
Check: EMG waveform log names the error and the single correction.
Hide EMG display
Repeat a matched block with EMG display hidden or delayed if Jo's EMG therapist approves, while using the same shoulder-release action.
Why: This tests immediate dependence on feedback.
Check: Feedback state is labelled and the rest of the configuration is unchanged.
Check function and recovery
End the shoulder-release cue, inspect electrode site and complete the therapist-chosen supported-reach or symptom check.
Why: A better trace matters only if burden, safety and intended function are not worse.
Check: Skin is intact, symptoms remain acceptable, and the supported-reach result is recorded separately.
Label three EMG signatures
While the arm is supported, Jo's EMG therapist records a quiet-muscle segment, one gentle shoulder activation and one deliberately marked lead-motion segment that does not pull on the skin. Jo names which trace segment is physiology and which is artefact before training begins.
Why: Jo cannot use an EMG graph safely if a cable bump and a muscle response look equally meaningful.
Check: Quiet, activation and marked artefact segments are retained with time labels, and Jo classifies all three correctly.
Compare matching reach phases
Divide each supported reach into start, lift, place and return. Compare the chosen shoulder cue only within matching phase across resting-trace, visible-screen and hidden-screen intervals; do not compare a moving phase with quiet sitting.
Why: Surface EMG varies with shoulder action being performed, so phase matching is needed before a smaller trace can be attributed to the cue.
Check: Every interval has matching object, reach distance, pace and four phase markers, with discomfort and movement quality recorded beside EMG trace.
4 · Worked example
See the whole method used once
Scenario
An occupational therapist uses surface EMG biofeedback to help Jo notice excess upper-shoulder tension during a supported reach.
Walkthrough
Jo's EMG therapist explains that the electrodes measure local muscle electrical activity, not stress as a whole.
Jo rests for a baseline, then reaches once while Jo's EMG therapist marks motion artefact.
Jo repeats the reach while gently releasing the shoulder rather than forcing it down.
After one posture correction, Jo repeats with EMG display hidden.
Jo's EMG therapist records EMG summary, reach quality, discomfort, assistance and skin condition.
Before coaching, Jo's EMG therapist saves three labelled snippets: supported rest, gentle shoulder lift and a cable-motion artefact; Jo correctly distinguishes the broad activation rise from the sharp lead disturbance.
For the reach comparison, Jo's EMG therapist marks start, lift, place and return on every trace so Jo compares the lift phase with the lift phase rather than with resting baseline.
Result
Jo changes the selected EMG pattern during this supported reach and partly retains it without the EMG screen. The result belongs to this muscle, sensor placement and task; it is not proof of global relaxation or treatment success. The labelled trace snippets and phase-matched reaches show exactly what Jo learned from this EMG loop without turning the display into a general health reading.
5 · Right and wrong
Compare correct or safer execution with the common wrong version
Right and wrong comparison
Moment
Right / safer
Wrong / riskier
Why it matters
Signal definition
Use one named signal with units and a declared target.
Combine heart rate, temperature and a wellness score as if they were interchangeable.
Different signals have different meanings and artefacts.
Sensor quality
Verify placement and mark motion or contact artefact.
Treat every spike as a body response.
Noise can drive false learning.
Strategy
Change one comfortable action at a time.
Strain, hold the breath or change posture repeatedly to move EMG display.
Multiple or extreme actions obscure the mechanism and can cause symptoms.
Learning test
Add a matched display-hidden block.
Claim learning from feedback-visible trials alone.
A screen-dependent change may disappear when feedback is removed.
Outcome
Record signal, function, symptoms, plus burden separately.
Call a prettier graph proof of health improvement.
A proxy signal is not the functional outcome.
A sharp EMG excursion when electrode lead moves
Mark the lead-motion interval as artefact and repeat after electrode lead is secured.
Treat the spike as a successful muscle contraction or a symptom flare.
A disturbed lead can change the displayed voltage without representing intended shoulder action.
Visible-screen and hidden-screen transfer
Match foam puck, reach distance, pace and reach phase before comparing EMG traces.
Compare a seated rest value with an active reach and call the difference loss of control.
Action phase is part of the EMG measurement configuration.
6 · Common mistakes
Spot the error and apply the correction
Common mistakes and corrections
Mistake
Fix
Electrode or probe contact changes between baseline and guided intervals.
Recheck placement marks and signal quality before comparing intervals; label any reattachment as a new configuration.
Jo watches individual pixels and changes strategy after every spike.
Use Jo's EMG therapist-selected interval trend and wait through EMG waveform’s response delay before judging the cue.
Breathing, posture, facial tension and limb effort all change together.
Return to baseline, choose one observable regulation cue and hold other posture and breathing features constant.
Motion artefact is celebrated because it moves EMG graph in the target direction.
Mark movement/speech epochs, exclude them under declared rule and repeat only after EMG trace stabilises.
A successful visible-screen interval is called learning.
Require a matched hidden-screen interval and a separate functional check before describing retention or usefulness.
EMG waveform target becomes an absolute normal value copied from another person.
Use Jo's EMG therapist-defined direction and personal task baseline; do not turn a training display into diagnosis.
7 · Practice
Turn the steps into a usable skill
First session
Jo and the EMG therapist name the upper-shoulder electrode site, supported foam-puck reach, shoulder-release cue and symptom stop.
Save a quiet-muscle waveform, gentle-activation waveform and marked lead-motion artefact; Jo classifies all three before coaching.
Record one supported reach without the screen cue, marking start, lift, place and return on the EMG trace.
Run two visible-screen reaches with the same puck, distance and pace; change only the shoulder-release cue after the first comparison.
Repeat one matched reach with the EMG screen hidden, then inspect the electrode site and score reach quality, discomfort and assistance.
Repeat plan
Jo's EMG therapist sets signal-specific sessions and dose. Progress only after stable sensor quality and reproducible, symptom-free performance; then fade feedback or vary one task feature. Screen-hidden retention and functional value must be tested directly. For the next appointment, repeat matching supported object transfer and phase markers before changing reach distance or load; fade EMG screen only when artefact classification remains accurate.
Progress when
Jo correctly distinguishes quiet muscle activity, gentle activation and marked lead-motion artefact before changing the shoulder cue.
The start, lift, place and return phases are marked consistently on every supported foam-puck reach.
Lift-phase EMG changes in the intended direction on matched visible-screen and hidden-screen reaches without worse discomfort, assistance or movement quality.
Do not progress when
The resting EMG waveform drifts, an electrode detaches or cable artefact cannot be separated from muscle activation.
Jo must brace, hold the breath, force the shoulder downward or worsen pain to move the display.
The waveform changes but the supported reach becomes less accurate, more effortful or more distressing.
8 · Check the result
Measure what changed
Signal-specific learning, screen-hidden retention, functional transfer, burden and harms
How: Jo's EMG therapist records electrode site plus sensor type, calibration, block summary, artefact time, feedback state, the shoulder-release action, symptoms, burden and the separate supported-reach outcome. For Jo's surface-EMG fixture, retain the three signature snippets and phase markers for start, lift, place and return; report excluded cable-motion time separately from valid muscle activity.
Good result: A reproducible signal-specific change appears in matched blocks, persists at least partly without visible feedback and does not worsen intended function or symptoms.
This does not prove: A changed surface-EMG waveform does not diagnose stress, prove whole-body relaxation or establish transfer to another muscle, electrode placement, task or clinical outcome.
Self-check
Can you demonstrate “Check signal quality”? EMG trace is stable at rest and changes appropriately during the check.
Can you demonstrate “Read trends, not flicker”? Artefact periods are marked and excluded under the predeclared rule.
Can you demonstrate “Check function and recovery”? Skin is intact, symptoms remain acceptable, and the supported-reach result is recorded separately.
Can you point to the saved quiet-muscle, gentle-activation and cable-artefact snippets and explain why only first two reflect muscle-state examples?
Can you compare lift with lift and return with return instead of comparing an active reach with supported rest?
9 · Stop, adapt or get help
Keep the safety boundary practical
Stop and get help
Stop for chest pain, faintness, severe breathlessness, neurological symptoms, panic, painful muscle spasm or a new concerning symptom.
Stop for broken skin, allergic reaction, heat, shock sensation or EMG-unit malfunction or an electrode-site problem.
Seek qualified review when feedback provokes compulsive monitoring, distress or a worsening clinical symptom.
Accessibility and adaptations
Provide audio, haptic or simplified colour-safe feedback instead of a dense graph.
Place sensors and supports around Jo’s mobility, skin and communication needs.
Allow a support person to manage the equipment while Jo performs the chosen shoulder-release action.
10 · Evidence and limits
Why these instructions are here
primary research
A randomised trial compared HRV biofeedback with other stress-reduction approaches, supporting signal- and protocol-specific interpretation.
The sensor, preprocessing, feedback rule and task form one versioned system; proxy validity and device-off performance must be tested separately.
Unsupported claim: hack your nervous system.
Unsupported claim: a high HRV score means health.
Unsupported claim: wearables diagnose stress.
Performance with one sensor, placement and task does not establish direct control of an organ, diagnosis, cure or transfer to another biofeedback system.
Paul M Lehrer; Evgeny Vaschillo; Bronya Vaschillo; Shou-En Lu; Dwain L Eckberg; Robert Edelberg; Weichung Joe Shih; Yong Lin; Tom A Kuusela; Kari U O Tahvanainen; Robert M Hamer · 2003 · Primary research
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Step-by-step learner mode
Each activity includes its success check, a nearby accessible alternative and an “I’m stuck” correction path. Alternatives preserve the target where possible; when they change the task, Titan labels them as related rather than equivalent.
01
Name the loop
Say what the surface electrodes measure, how EMG display represents it, what action you will try and what outcome matters beyond EMG display.
Why this step exists
A clear person-sensor-feedback-task loop prevents vague “body control” claims.
Success check
Jo can point to each link and name the measurement unit.
I’m stuck on this step
Reset: Re-read this authored instruction — “Say what the surface electrodes measure, how EMG display represents it, what action you will try and what outcome matters beyond EMG display.” — and its success check, then attempt only this step.
Possible snag: The result from “Say what the surface electrodes measure, how EMG display represents it, what action you will try and what outcome matters beyond EMG display.” does not yet meet this declared check: Jo can point to each link and name the measurement unit.
Correction: Return to the start of “Name the loop”, reduce complexity or pace, and repeat only the part needed to satisfy: “Jo can point to each link and name the measurement unit.”
Stop / get help: Stop for chest pain, faintness, severe breathlessness, neurological symptoms, panic, painful muscle spasm or a new concerning symptom.
02
Check signal quality
Jo's EMG therapist places surface electrodes, follows EMG unit check and asks Jo to make a known small action to confirm that EMG display responds as expected.
Why this step exists
Poor contact, motion and electrical noise can masquerade as physiology.
Success check
EMG trace is stable at rest and changes appropriately during the check.
I’m stuck on this step
Reset: Re-read this authored instruction — “Jo's EMG therapist places surface electrodes, follows EMG unit check and asks Jo to make a known small action to confirm that EMG display responds as expected.” — and its success check, then attempt only this step.
Possible snag: Electrode or probe contact changes between baseline and guided intervals.
Correction: Recheck placement marks and signal quality before comparing intervals; label any reattachment as a new configuration.
Possible snag: EMG waveform target becomes an absolute normal value copied from another person.
Correction: Use Jo's EMG therapist-defined direction and personal task baseline; do not turn a training display into diagnosis.
Stop / get help: Stop for chest pain, faintness, severe breathlessness, neurological symptoms, panic, painful muscle spasm or a new concerning symptom.
03
Capture a quiet baseline
Complete a therapist-timed EMG interval without using shoulder-release cue. Record posture, support, signal and artefacts.
Why this step exists
A baseline shows drift and normal variation before feedback learning.
Success check
The raw baseline remains visible and is not discarded for looking untidy.
I’m stuck on this step
Reset: Re-read this authored instruction — “Complete a therapist-timed EMG interval without using shoulder-release cue. Record posture, support, signal and artefacts.” — and its success check, then attempt only this step.
Possible snag: The result from “Complete a therapist-timed EMG interval without using shoulder-release cue. Record posture, support, signal and artefacts.” does not yet meet this declared check: The raw baseline remains visible and is not discarded for looking untidy.
Correction: Return to the start of “Capture a quiet baseline”, reduce complexity or pace, and repeat only the part needed to satisfy: “The raw baseline remains visible and is not discarded for looking untidy.”
Stop / get help: Stop for chest pain, faintness, severe breathlessness, neurological symptoms, panic, painful muscle spasm or a new concerning symptom.
04
Apply one strategy
Use only the agreed action, such as releasing a selected muscle or making an easy breathing change, during the feedback block.
Why this step exists
Changing several things at once hides which action affected EMG waveform.
Success check
Shoulder-release cue is observable and stays within comfortable effort.
I’m stuck on this step
Reset: Re-read this authored instruction — “Use only the agreed action, such as releasing a selected muscle or making an easy breathing change, during the feedback block.” — and its success check, then attempt only this step.
Possible snag: The result from “Use only the agreed action, such as releasing a selected muscle or making an easy breathing change, during the feedback block.” does not yet meet this declared check: Shoulder-release cue is observable and stays within comfortable effort.
Correction: Return to the start of “Apply one strategy”, reduce complexity or pace, and repeat only the part needed to satisfy: “Shoulder-release cue is observable and stays within comfortable effort.”
Stop / get help: Stop for chest pain, faintness, severe breathlessness, neurological symptoms, panic, painful muscle spasm or a new concerning symptom.
05
Read trends, not flicker
Watch the therapist-selected EMG trend and ignore isolated spikes. Pause when movement, speech or sensor contact creates an artefact.
Why this step exists
Closed-loop learning depends on valid feedback, not chasing noise.
Success check
Artefact periods are marked and excluded under the predeclared rule.
I’m stuck on this step
Reset: Re-read this authored instruction — “Watch the therapist-selected EMG trend and ignore isolated spikes. Pause when movement, speech or sensor contact creates an artefact.” — and its success check, then attempt only this step.
Possible snag: Jo watches individual pixels and changes strategy after every spike.
Correction: Use Jo's EMG therapist-selected interval trend and wait through EMG waveform’s response delay before judging the cue.
Possible snag: Motion artefact is celebrated because it moves EMG graph in the target direction.
Correction: Mark movement/speech epochs, exclude them under declared rule and repeat only after EMG trace stabilises.
Stop / get help: Stop for chest pain, faintness, severe breathlessness, neurological symptoms, panic, painful muscle spasm or a new concerning symptom.
06
Correct one error
Use the EMG therapist’s feedback to change one feature—posture, effort, cue timing or sensor contact—and repeat a matched block.
Why this step exists
One controlled correction makes cause and effect easier to interpret.
Success check
EMG waveform log names the error and the single correction.
I’m stuck on this step
Reset: Re-read this authored instruction — “Use the EMG therapist’s feedback to change one feature—posture, effort, cue timing or sensor contact—and repeat a matched block.” — and its success check, then attempt only this step.
Possible snag: Breathing, posture, facial tension and limb effort all change together.
Correction: Return to baseline, choose one observable regulation cue and hold other posture and breathing features constant.
Stop / get help: Stop for chest pain, faintness, severe breathlessness, neurological symptoms, panic, painful muscle spasm or a new concerning symptom.
07
Hide EMG display
Repeat a matched block with EMG display hidden or delayed if Jo's EMG therapist approves, while using the same shoulder-release action.
Why this step exists
This tests immediate dependence on feedback.
Success check
Feedback state is labelled and the rest of the configuration is unchanged.
I’m stuck on this step
Reset: Re-read this authored instruction — “Repeat a matched block with EMG display hidden or delayed if Jo's EMG therapist approves, while using the same shoulder-release action.” — and its success check, then attempt only this step.
Possible snag: The result from “Repeat a matched block with EMG display hidden or delayed if Jo's EMG therapist approves, while using the same shoulder-release action.” does not yet meet this declared check: Feedback state is labelled and the rest of the configuration is unchanged.
Correction: Return to the start of “Hide EMG display”, reduce complexity or pace, and repeat only the part needed to satisfy: “Feedback state is labelled and the rest of the configuration is unchanged.”
Stop / get help: Stop for chest pain, faintness, severe breathlessness, neurological symptoms, panic, painful muscle spasm or a new concerning symptom.
08
Check function and recovery
End the shoulder-release cue, inspect electrode site and complete the therapist-chosen supported-reach or symptom check.
Why this step exists
A better trace matters only if burden, safety and intended function are not worse.
Success check
Skin is intact, symptoms remain acceptable, and the supported-reach result is recorded separately.
I’m stuck on this step
Reset: Re-read this authored instruction — “End the shoulder-release cue, inspect electrode site and complete the therapist-chosen supported-reach or symptom check.” — and its success check, then attempt only this step.
Possible snag: The result from “End the shoulder-release cue, inspect electrode site and complete the therapist-chosen supported-reach or symptom check.” does not yet meet this declared check: Skin is intact, symptoms remain acceptable, and the supported-reach result is recorded separately.
Correction: Return to the start of “Check function and recovery”, reduce complexity or pace, and repeat only the part needed to satisfy: “Skin is intact, symptoms remain acceptable, and the supported-reach result is recorded separately.”
Stop / get help: Stop for chest pain, faintness, severe breathlessness, neurological symptoms, panic, painful muscle spasm or a new concerning symptom.
09
Label three EMG signatures
While the arm is supported, Jo's EMG therapist records a quiet-muscle segment, one gentle shoulder activation and one deliberately marked lead-motion segment that does not pull on the skin. Jo names which trace segment is physiology and which is artefact before training begins.
Why this step exists
Jo cannot use an EMG graph safely if a cable bump and a muscle response look equally meaningful.
Success check
Quiet, activation and marked artefact segments are retained with time labels, and Jo classifies all three correctly.
I’m stuck on this step
Reset: Re-read this authored instruction — “While the arm is supported, Jo's EMG therapist records a quiet-muscle segment, one gentle shoulder activation and one deliberately marked lead-motion segment that does not pull on the skin. Jo names which trace segment is physiology and which is artefact before training begins.” — and its success check, then attempt only this step.
Possible snag: The result from “While the arm is supported, Jo's EMG therapist records a quiet-muscle segment, one gentle shoulder activation and one deliberately marked lead-motion segment that does not pull on the skin. Jo names which trace segment is physiology and which is artefact before training begins.” does not yet meet this declared check: Quiet, activation and marked artefact segments are retained with time labels, and Jo classifies all three correctly.
Correction: Return to the start of “Label three EMG signatures”, reduce complexity or pace, and repeat only the part needed to satisfy: “Quiet, activation and marked artefact segments are retained with time labels, and Jo classifies all three correctly.”
Stop / get help: Stop for chest pain, faintness, severe breathlessness, neurological symptoms, panic, painful muscle spasm or a new concerning symptom.
10
Compare matching reach phases
Divide each supported reach into start, lift, place and return. Compare the chosen shoulder cue only within matching phase across resting-trace, visible-screen and hidden-screen intervals; do not compare a moving phase with quiet sitting.
Why this step exists
Surface EMG varies with shoulder action being performed, so phase matching is needed before a smaller trace can be attributed to the cue.
Success check
Every interval has matching object, reach distance, pace and four phase markers, with discomfort and movement quality recorded beside EMG trace.
I’m stuck on this step
Reset: Re-read this authored instruction — “Divide each supported reach into start, lift, place and return. Compare the chosen shoulder cue only within matching phase across resting-trace, visible-screen and hidden-screen intervals; do not compare a moving phase with quiet sitting.” — and its success check, then attempt only this step.
Possible snag: A successful visible-screen interval is called learning.
Correction: Require a matched hidden-screen interval and a separate functional check before describing retention or usefulness.
Stop / get help: Stop for chest pain, faintness, severe breathlessness, neurological symptoms, panic, painful muscle spasm or a new concerning symptom.
Correct versus incorrect execution
These accessible process diagrams are built from the tutorial’s own right/wrong teaching. They are not anatomical illustrations and do not add technique beyond the canonical tutorial.
Signal definition — Different signals have different meanings and artefacts.
Correct / safer
Use one named signal with units and a declared target.
Wrong / riskier
Combine heart rate, temperature and a wellness score as if they were interchangeable.
Sensor quality — Noise can drive false learning.
Correct / safer
Verify placement and mark motion or contact artefact.
Wrong / riskier
Treat every spike as a body response.
Strategy — Multiple or extreme actions obscure the mechanism and can cause symptoms.
Correct / safer
Change one comfortable action at a time.
Wrong / riskier
Strain, hold the breath or change posture repeatedly to move EMG display.
Learning test — A screen-dependent change may disappear when feedback is removed.
Correct / safer
Add a matched display-hidden block.
Wrong / riskier
Claim learning from feedback-visible trials alone.
Outcome — A proxy signal is not the functional outcome.
Correct / safer
Record signal, function, symptoms, plus burden separately.
Wrong / riskier
Call a prettier graph proof of health improvement.
A sharp EMG excursion when electrode lead moves — A disturbed lead can change the displayed voltage without representing intended shoulder action.
Correct / safer
Mark the lead-motion interval as artefact and repeat after electrode lead is secured.
Wrong / riskier
Treat the spike as a successful muscle contraction or a symptom flare.
Visible-screen and hidden-screen transfer — Action phase is part of the EMG measurement configuration.
Correct / safer
Match foam puck, reach distance, pace and reach phase before comparing EMG traces.
Wrong / riskier
Compare a seated rest value with an active reach and call the difference loss of control.
Method-structure checklist
10 of 10 structural checks present
✓ Ordered, Power-specific instructions — present
✓ Every activity has a success check — present
✓ Materials or supplied records are declared — present
✓ Measurement or assessment rule is present — present
✓ Tutorial-specific troubleshooting is present — present
✓ Stopping or escalation boundary is present — present
✓ Every activity has an adjacent alternative — present
✓ Correct-versus-incorrect comparison is present — present
✓ Evidence context is bound to the Power record — present
✓ Planning metadata is present — present
The method-readiness band and presence checklist assess tutorial presentation and are separate from evidence quality for the underlying Power. They are automated editorial aids, not human approval.
Manual editorial sign-off: Pending. This tutorial must not display a human-approved state until an identified editor signs the exact content hash.