CVR Physiotherapy › Technique cards › Breathing and breathlessness
Respiratory muscle training
Asked as "two types of inspiratory muscle training" (S18, 3 marks), "therapeutic exercise programme to strengthen respiratory muscles" (W22, 7 marks) and within diaphragm strengthening (S21). Know the types, the dose (30% or more of maximal inspiratory pressure) and who benefits.
- Syllabus
- Ch 4(j) Therapeutic exercise program to strengthen respiratory muscles; practical: ventilatory muscle training
- Priority
- Moderate. In 3 of 20 papers (2016–2026).
- Asked as
- 7m S21W22 3m S18
- Usual split
- 3-mark types; 7-mark programme
- Checked against
- ATS/ERS statement on respiratory muscle testing (2002); meta-analysis of inspiratory muscle training in COPD (2011); IMT in COPD trial (2018); IMT and weaning review (2015). Full list under Sources.
- Content checked
- 19 October 2026. Next review due October 2027.
- My revision
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1Why train the breathing muscles
Breathing muscles can be weak (low strength) or overloaded (stiff lungs, airway obstruction, hyperinflation), and both cause breathlessness, poor exercise tolerance, a weak cough and failure to wean from a ventilator. Like limb muscles, they get stronger with progressive overload.
- Measure: maximal inspiratory pressure (MIP or PImax) and maximal expiratory pressure (MEP) with a mouth pressure meter. A MIP stronger than about −80 cmH₂O usually rules out important inspiratory weakness; in COPD, a MIP weaker than about 60 cmH₂O marks the patients who gain most from training.
- Who benefits: COPD with inspiratory muscle weakness, heart failure, before high-risk heart, lung or abdominal surgery, weaning failure in ICU, neuromuscular disease and spinal cord injury (early stages), dysfunctional breathing, athletes.
2Types of training (3 marks in S18)
| Type | How it works | Points |
|---|---|---|
| Threshold (pressure-threshold) loading | A spring-loaded valve opens only when the patient breathes in hard enough to reach a set pressure | Load does not depend on how fast the patient breathes; easy to set as a % of MIP; the most used type (handheld threshold trainers) |
| Inspiratory resistive (flow-resistive) training | Breathing in through a small opening; smaller holes give more resistance | The load depends on flow, so the patient must keep a set breathing pattern (or use a target device) |
| Normocapnic hyperpnoea (endurance training) | Breathing at a high minute ventilation for 10–30 minutes, with a rebreathing bag to keep CO₂ normal | Trains endurance; needs equipment and supervision |
| Electronic tapered-flow resistive loading | A device adjusts the resistance through each breath | Allows heavier loads comfortably; costly |
| Expiratory muscle training | Threshold device on the breath out | Cough, voice and swallowing in neuromuscular disease, Parkinson's disease, multiple sclerosis |
Older textbooks also describe abdominal weights (small weights on the upper abdomen in supine) and diaphragmatic resisted breathing by hand.
3Dose
| Part | Inspiratory muscle training (threshold) |
|---|---|
| Intensity | Start at about 30% of MIP; progress towards 50–60% or more as tolerated; re-measure MIP every 1–2 weeks |
| Volume | About 30 breaths (or about 15 minutes), twice a day |
| Frequency and duration | 5–7 days a week for at least 6–8 weeks, then a maintenance dose |
| Technique | Sitting upright, nose clip if needed, a quick strong breath in through the device, then a slow relaxed breath out; rest between sets |
4Precautions and contraindications
- Recent or untreated pneumothorax; recent lung or chest-wall surgery not yet healed.
- Acute exacerbation of COPD or asthma; unstable heart failure; recent heart attack.
- Perforated eardrum; raised intracranial pressure; active haemoptysis.
- Watch for fatigue (especially in neuromuscular disease, where overwork can harm weak muscles), dizziness and breathlessness; stop if they appear.
Classic answer vs current evidence: IMT in COPD
Classic
Give inspiratory muscle training to every COPD patient.
Current
On its own, IMT improves inspiratory strength, endurance, breathlessness and walking distance, most in patients with weak inspiratory muscles (meta-analysis, 2011). Added to a full pulmonary rehabilitation programme, it improved muscle strength but not exercise capacity in a 2018 trial. It is an add-on for weak patients, not a replacement for whole-body exercise. In ICU, IMT helps patients who fail weaning (review, 2015).
Write in the exam
"IMT at 30% or more of MIP, about 30 breaths twice a day for at least 8 weeks, for patients with inspiratory muscle weakness, alongside general exercise training."
5Exercise programme to strengthen respiratory muscles (7 marks in W22)
- Assess: MIP and MEP, breathing pattern, chest expansion, peak cough flow, breathlessness (Borg, mMRC), posture.
- Diaphragmatic breathing with facilitation and manual resistance, progressing from half-lying to sitting and standing.
- Inspiratory muscle training with a threshold device at the dose above.
- Expiratory muscle training and huffing practice where cough is weak; abdominal muscle strengthening (bracing, curl-ups as allowed).
- Accessory and postural muscles: scapular and upper-limb exercise (arm ergometry, resisted arm patterns), thoracic mobility.
- Whole-body aerobic training (walking, cycling): the ventilatory load of exercise also trains the breathing muscles.
- Endurance: normocapnic hyperpnoea where available; singing or wind-instrument games for children.
- Progress and review every 1–2 weeks; re-measure MIP; adjust load.
6Exam corner
Past questions (MUHS, 2016–2026)
- 7-mark questionsDiaphragm recruitment and strengthening (S21; see the breathing exercises card). Therapeutic exercise programme to strengthen respiratory muscles (W22).
- 3-mark questionWrite two types of inspiratory muscle training (S18).
Test yourself
3 mDifferentiate threshold loading from resistive training.
Threshold: a spring valve opens at a set pressure, so the load is fixed whatever the flow. Resistive: breathing through a small hole, so the load rises with faster flow and the breathing pattern must be controlled.
MCQA common starting intensity for inspiratory muscle training is:A. 5% of MIPB. 30% of MIPC. 90% of MIPD. 150% of MIP
B. About 30% of MIP, progressed as tolerated.
Sources
- MUHS BPTh syllabus (2012) and MUHS IV BPTh question papers 2016–2026 (muhsonline.com, unofficial archive; Dhole Patil College of Physiotherapy past-paper page).
- American Thoracic Society/European Respiratory Society. ATS/ERS statement on respiratory muscle testing. Am J Respir Crit Care Med 2002;166:518–624.
- Gosselink R, et al. Impact of inspiratory muscle training in patients with COPD: what is the evidence? Eur Respir J 2011;37:416–25.
- Charususin N, et al. Randomised controlled trial of adjunctive inspiratory muscle training for patients with COPD. Thorax 2018;73:942–50.
- Elkins M, Dentice R. Inspiratory muscle training facilitates weaning from mechanical ventilation among patients in the intensive care unit: a systematic review. J Physiother 2015.
- Hulzebos EHJ, et al. Preoperative intensive inspiratory muscle training to prevent postoperative pulmonary complications in high-risk patients undergoing CABG surgery. JAMA 2006.
- Structure and classical content: Frownfelter & Dean (2022); Pryor & Prasad (2008).
Educational notes for exam preparation. Not medical advice.
Version 1. Content checked 19 October 2026. Next review October 2027.