EXSS3070 Week 11 Lecture

Slide 1 – Title & Context

• Unit/Lecture: EXSS3070 | Advanced Exercise Programming & Delivery – “Respiratory (Patho)physiology – a Refresher”.

• Presenter: Dr Troy J Cross, PhD, Senior Lecturer, Discipline of Exercise & Sport Science, The University of Sydney.

• Signals that respiratory content underpins later exercise-for-asthma programming.

Slide 2 – Initial Learning Objectives

1. Purpose of breathing – gas exchange and non-respiratory roles.

2. Respiratory anatomy – conducting vs respiratory zones, airway walls.

3. Pulmonary function tests (PFTs) – spirogram, volume-time, flow-volume.

4. Disease spectrum – restrictive, obstructive, mixed.

5. Hallmark obstructive symptoms – cough & dyspnoea.

Slide 3 – Resources

• ESSA position statements (link shown on slide) summarise best-practice assessment & exercise prescription for respiratory disorders. Download and file them for future clinical placement use.

SECTION 1 | Fundamentals of Breathing

Slide 4 – Respiratory Purpose

• Primary goal: maintain arterial gases within narrow limits: PaO₂ ≈ 80–100 mmHg, PaCO₂ ≈ 35–45 mmHg; stabilises arterial pH at 7.35–7.45 via CO₂ buffering.

• Requires tight V̇A/Q̇ (ventilation-perfusion) matching and intact alveolar–capillary diffusion.

Slide 5 – Non-Respiratory Roles

• Valsalva-like maneuvers for emesis, defecation, parturition.

• Airflow for phonation & swallowing.

• Thoracic pump modulates venous return & cardiac output.

• Thermoregulation via evaporative heat loss in expired air.

Slide 6 – Macro-Anatomy Overview

• Upper airways: nasal/oral cavities → pharynx → larynx.

• Lower airways: trachea → 1° bronchi → 23 generations of branching to alveolar sacs.

• Distinct conducting vs respiratory zones introduced.

Slide 7 – Conducting vs Respiratory Zones

Slide 8 – Tracheal Cross-Section

• C-shaped cartilage prevents collapse; posterior smooth muscle permits oesophageal expansion.

• Mucociliary escalator sweeps debris cephalad; smoking destroys cilia → chronic cough.

Slide 9 – Airway Branching & Surface Area

• 23 generations create ~300 million alveoli; exchange surface ≈ 70–100 m².

• Parallel branching multiplies cross-sectional area → velocity of airflow plummets distally, aiding diffusion & particle deposition.

Slide 10 – Airway Wall Layers

1. Inner mucosa: ciliated epithelium + goblet cells (mucus).

2. Submucosa & cartilage/CT: glands, vessels, nerves.

3. Airway smooth-muscle (ASM): constricts/relaxes lumen; hypertrophies in asthma.

SECTION 2 | Pulmonary Function Testing

Slide 11 – Spirogram Graph

• Annotated lung volumes & capacities:
  

  • Static: TLC, FRC, RV.

  • Dynamic: VT (~500 mL), IRV, ERV, VC (~80% TLC).

• Emphasise “capacity = two or more volumes”.

Slide 12 – Spirometric Definitions & Norms

• TLC ≈ 6 L (♂) / 4.2 L (♀).

• FRC = RV + ERV; baseline lung volume at end-tidal expiration.

• Clinical: ↓TLC & VC with normal FEV₁/FVC suggests restriction; ↓FEV₁ & ratio suggests obstruction.

Slide 13 – Volume-Time Manoeuvre Protocol

1. Inspire to TLC.

2. Explode into forced expiration (no pause).

3. Continue ≥ 6 s or until plateau.

4. Optional reinspiration to TLC shows flow-volume loop closure.

• Must coach maximal effort; sub-max blows under-diagnose obstruction.

Slide 14 – Key Indices from Volume-Time

• FEV₁: volume exhaled in 1 s; ↓ in asthma/COPD.

• FVC: maximal exhaled volume.

• FEV₁/FVC (Tiffeneau index): < 0.70 (post-bronchodilator) ⇒ obstructive disease.

Slide 15 – Flow-Volume Loop Patterns

(Text not visible in preview; expanded for completeness)

• Normal: rapid peak flow then linear descent.

• Obstructive: scooped-out expiratory limb, ↓PEF.

• Restrictive: narrow loop, PEF preserved, volumes compressed.

• Loop analysis quickly differentiates pathologies during clinical screening.

SECTION 3 | Pulmonary Disorders

Slide 16 – Spectrum Overview

• Disorders classified by predominant pathophysiology: restrictive, obstructive, mixed.

• Flow-volume archetypes shown for each.

Slide 17 – Restrictive Disorders (Pathophysiology)

• Intrinsic: interstitial fibrosis, pneumonitis → stiff parenchyma.

• Extrinsic: kyphoscoliosis, neuromuscular weakness, pleural effusion.

• Spirometry: ↓TLC, FRC, RV, VC; flows often normal/↑ relative to volume.

Slide 18 – Obstructive Disorders (Pathophysiology)

• Primary issue = airflow limitation on expiration.

• Episodic (asthma) vs chronic (COPD = chronic bronchitis + emphysema).

• Hyperinflation ↑FRC/RV; diaphragm flattens.

Slide 19 – Mixed Patterns

• Combines low volumes and low flows; e.g., pneumoconiosis with airway inflammation.

Slide 20 – Flow-Volume Morphology Examples

(Assumed visuals)

• Learning point: recognise “coving” (obstruction) vs “compressed but tall” (restriction).

Slides 21 & 22 – Visual Chest X-ray/CT Comparisons

• Restrictive: reticular opacities, small lung fields.

• Obstructive: hyperlucent lungs, flattened diaphragms.

Slide 23 – Obstructive Disorders Focus (Asthma/COPD)

• Transition to detailed mechanism slides.

Slide 24 – Airway Narrowing Mechanisms

1. Mucous plugging from goblet cell hyperplasia.

2. Wall thickening: ASM contraction + oedema + remodelling.

3. Loss of radial traction: parenchymal destruction removes tethering.

Slide 25 – Hallmark Obstructive Symptoms

• Cough & Dyspnoea: shared across asthma, COPD, bronchiectasis.

Slide 26 – Cough Physiology

• Protective reflex powered by rapid-flow “expiratory blast” (high intrathoracic pressure).

• Effective cough clears secretions (expectoration).

Slide 27 – Acute vs Chronic Cough Aetiology

• Acute (< 3 wk): viral URTI, allergic rhinitis.

• Chronic (> 3 wk): smoking-related COPD, uncontrolled asthma, GORD, ACE-inhibitors.

Slide 28 – Intact Mucociliary Clearance

• Healthy cilia transport ~100 mL mucus/day to oropharynx → swallow; cough frequency low.

Slide 29 – Impaired Ciliary Function

• Smoking/pollutants destroy cilia → retained secretions → productive cough becomes main clearance route.

Slide 30 – Dyspnoea: Multidimensional Symptom

• Sensory components: work/effort of breathing, air hunger, chest tightness.

• Affective components: anxiety, fear, depression; dyspnoea-anxiety-dyspnoea spiral mirrors chronic pain cycles.

Slide 31 – Formal Definition

• “Subjective experience of breathing discomfort comprising qualitatively distinct sensations varying in intensity.”

Slide 32 – The Dyspnoea Spiral

• ↓Activity → deconditioning → ↑ventilatory drive at low workloads → worse breathlessness → further inactivity. Exercise training aims to break this loop.

Slide 33 – Measuring Dyspnoea: Overview

• Situational (during exercise) vs baseline (ADL).

Slide 34 – MRC & mMRC Scales

• Grade 0 (no dyspnoea except strenuous exercise) → Grade 4 (too breathless to leave house).

• mMRC widely used in COPD severity classification (GOLD guidelines).

Slide 35 – Visual Analog Scale (VAS)

• 100 mm line; patient marks perceived intensity. Reliable if standardised descriptors used.

Slide 36 – Category-Ratio 10 (Modified Borg)

• Non-linear anchors: 0 = nothing, 10 = maximal.

• CR10 preferred during incremental tests (e.g., CPET) because near-linear relation with log-ventilation.

Slide 37 – Multidimensional Dyspnoea Profile (MDP)

• Separates sensory quality, immediate discomfort, emotional response.

• Impractical mid-exercise but valuable in research or pulmonary rehab assessment.

Slide 38 – Learning Objectives Checkpoint (ticks)

• Slide shows completed objectives; confirms end of physiology section.

SECTION 4 | Asthma Part 1 – Fundamentals

Slide 39 – New Title: “Exercise Considerations for Asthma”

• Marks shift from generic respiration to asthma-specific programming.

Slide 40 – Asthma Section Objectives

1. Define asthma & prevalence.

2. Diagnostic pathway.

3. Pharmacological & non-pharmacological treatment.

4. Exercise programming nuances.

Slide 41 – Epidemiology

• 2 million Australians diagnosed; male bias (3:2) in childhood; prevalence peaks in first decade then stabilises.

Slide 42 – Definition & Core Pathology

• Chronic inflammatory disorder of ASM → airway hyperresponsiveness (AHR) + reversible bronchoconstriction episodes.

Slide 43 – Common Triggers

• Allergens (dust mite, pollen), cold dry air, respiratory infections, exercise, air pollutants, drugs (β-blockers, NSAIDs); chloramines in indoor pools, tobacco smoke.

Slide 44 – Exercise-Induced Bronchoconstriction (EIB)

• Mechanism: high ventilatory rates → airway dehydration & cooling → ↑osmolarity → mediator release (leukotrienes, prostaglandins) → ASM contraction. Symptoms during or ~5–10 min post-exercise.

Slide 45 – Frequent Comorbidities

• Rhinitis/rhinosinusitis, GORD, obesity, OSA, depression, anxiety. Addressing these improves asthma control.

Slide 46 – Mechanistic Triad of Airway Narrowing

1. ASM bronchoconstriction.

2. Wall thickening (inflammation, oedema).

3. Excess mucus production.

SECTION 5 | Asthma Part 2 – Diagnosis

Slide 47 – Diagnostic Step 1: Symptom History

• Dyspnoea, cough, wheeze, chest tightness, nocturnal awakenings; ask about pattern & triggers.

Slide 48 – Step 2: Baseline Spirometry Decision Tree

• Compare FEV₁, FVC, ratio to LLN (lower limit normal). Normal spirometry does not exclude asthma if quiescent.

Slide 49 – Step 3: Bronchodilator Reversibility

• Post-salbutamol ↑FEV₁ or FVC > 10 % predicted (or > 200 mL absolute) = reversible obstruction.

Slide 50 – Step 4: Bronchoprovocation Testing

• Required when baseline spirometry ± reversibility inconclusive.

Slide 51 – Direct Challenge (Methacholine/Histamine)

• Escalating doses until FEV₁ falls 20 % (PD₂₀). High sensitivity; positive test confirms AHR but doesn’t prove active asthma.

Slide 52 – Indirect Exercise Challenge

• 6–8 min at 80–90 % HRmax breathing dry air (≤ 10 mg H₂O·L⁻¹). Serial spirometry @ 5, 10, 15, 30 min post. ≥ 10 % FEV₁ fall = EIB; classify mild < 25 %, moderate 25–49 %, severe ≥ 50 %.

Slide 53 – Additional Indirect Tests

• Mannitol inhalation, eucapnic voluntary hyperventilation (EVH), hypertonic saline. Useful when exercise lab unavailable.

SECTION 6 | Asthma Part 3 – Management

Slide 54 – Management Goals

• Symptom control, prevent exacerbations, maintain lung function, minimise medication side-effects.

Slide 55 – Pulmonary Function Monitoring

• Document at diagnosis, again 3–6 months after therapy initiation, then periodically (≥ annually).

Slide 56 – Patient Responsibilities

• Education on disease, inhaler technique, adherence (target > 80 % although typical ≈ 70 %), written action plan, peak-flow diary, regular medical reviews.

Slides 57 & 58 – Pharmacotherapy Ladder

(content implied)

• Relievers: short-acting β₂-agonists (SABA).

• Controllers: inhaled corticosteroids (ICS) ± long-acting β₂-agonists (LABA).

• Add-on: leukotriene receptor antagonists, monoclonal antibodies for severe eosinophilic asthma.

Slide 59 – Exercise Training as Adjunct Therapy

• Aerobic conditioning ↓V̇E (ventilation) at given workload → less airway dehydration → ↓EIB severity; improves QoL and anxiety.

SECTION 7 | Asthma Part 4 – Exercise Prescription

Slide 60 – “ExRx?” Prompt Slide

• Sets stage to translate pathophysiology into FITT guidelines.

Slide 61 – Criteria for

Well-Controlled

Asthma

• No nocturnal or morning symptoms, no rescue inhaler use, unrestricted ADL, no recent exacerbations. Only under these conditions follow standard ACSM guidelines.

Slide 62 – General FITT Recommendation

• Frequency: 3–5 d·wk⁻¹.

• Intensity: 40–59 % HRR progressing to 60–70 % as tolerated.

• Time: 20–60 min; interval format (e.g., 10 min bouts) reduces EIB risk.

• Type: Rhythmic large-muscle aerobic (cycling, brisk walking, swimming) + 2 resistance sessions/wk to offset corticosteroid myopathy.

Slide 63 – Medication Timing & Access

• Administer controller & preventer meds ~(15 min) pre-exercise; carry reliever inhaler at all times during sessions.

Slide 64 – Mode/Environment Considerations

• Swimming: warm, humid air → least “asthmagenic”; prefer non-chlorinated or outdoor pools (↓chloramines).

• Cold/dry weather: encourage nose breathing or mask; schedule indoors on high-risk days; check bush-fire & thunderstorm asthma alerts.

Slide 65 – Pollution & Allergen Exposure

• Road cycling → particulate matter (PM2.5) aggravates bronchoconstriction; choose low-traffic routes/times.

Slide 66 – Behavioural & Adherence Strategies

• Individualise activities for enjoyment; include goal setting, symptom tracking, positive reinforcement.

Slide 67 – Over-Training Syndrome (OTS) Risk

• Excessive load suppresses immunity → infection flare-ups; integrate periodisation & monitor RESTQ-Sport or HRV.

Slide 68 – Contra-Indications

• No reliever available ⇒ cancel session.

• Recent peak-flow or FEV₁ < 75 % personal best ⇒ reschedule.

• Standard ACSM absolute/relative cardio contraindications also apply.

Slide 69 – Read ESSA Position Statement Prompt

• Provides evidenced-based tables of exercise dosage, screening, and safety algorithms – download for quick reference before clinical placement.

SECTION 8 | Closing Slides

Slide 70 – Final Learning Objective Checklist

• Visually confirms all asthma goals met (tick marks).

Slide 71 – Summary Graphic / Key Take-Home

• “Asthma control → safe, beneficial exercise” emphasised; integrate physiology with programming.

Slide 72 – Questions / Discussion Cue

• Prepare to discuss: adapting FITT for cold-weather sport, inhaler technique coaching, comorbidity management.

Slide 73 – Thank-You / Contact Details

• Email: troy.cross@sydney.edu.au (assumed format).

Slides 74–77 – Spare / Backup (no core content)

• Some presenters keep additional figures or references; not examinable unless explicitly shown in class.

Rapid-Reference Tables (optional paste into your study sheet)

1. Spirometry Interpretation Cheat-Sheet
   

   • FEV₁/FVC < 0.70 (post-BD) ⇒ obstructive.

   • FVC ↓ < 80 % predicted with normal ratio ⇒ restrictive.

   • Bronchodilator ↑FEV₁ ≥ 10 % pred (≥ 200 mL) ⇒ reversible.

3. EIB Severity Classification
   | FEV₁ Fall from Baseline | Severity |
   |———————––|–––––|
   | 10–24 % | Mild |
   | 25–49 % | Moderate |
   | ≥ 50 % | Severe |

4. Modified Borg (CR10) Anchors
   0 = nothing, 0.5 = just noticeable, 3 = moderate, 5 = severe, 7 = very severe, 10 = maximal.