RESPIRATORY RESPIRATORY RESPONSE TO RESPONSE TO

EXERCISEEXERCISEbyby DIPAYAN SEN DIPAYAN SEN

33RDRD YEAR YEAR

MEDICAL COLLEGE, KOLKATAMEDICAL COLLEGE, KOLKATA

Respiratory system: Its significance Respiratory system: Its significance in exercisein exercise

EXERCISEEXERCISE

1. Anaerobic 1. Anaerobic ExerciseExercise

2. Aerobic 2. Aerobic ExerciseExercise

Respiration is Respiration is of relatively of relatively little concernlittle concern

Respiration is Respiration is critical for critical for maximal maximal

performanceperformance

Lung VolumesLung Volumes

Tidal VolumeTidal Volume

Inspiratory Reserve VolumeInspiratory Reserve Volume

Expiratory Reserve VolumeExpiratory Reserve Volume

Residual VolumeResidual Volume

Forced Vital Capacity Forced Vital Capacity (FVC)(FVC)

FEV1FEV1

FEV1 FVC

Oxygen Consumption in Oxygen Consumption in Exercise (VOExercise (VO22 max) max)

CONDITIONSCONDITIONS

MAXIMAL MAXIMAL OXYGEN OXYGEN

CONSUMPTION CONSUMPTION (ml/min) (ml/min)

Untrained average Untrained average malemale 36003600

Athletically trained Athletically trained average maleaverage male 40004000

Male marathon runnerMale marathon runner 51005100

Limits Of VentilationLimits Of VentilationPulmonary Ventilation at maximal Pulmonary Ventilation at maximal

exerciseexercise100-110 100-110

L/min L/minMaximal Breathing CapacityMaximal Breathing Capacity 150-170 150-170

L/minL/min

Abnormalities Abnormalities in the in the

respiratory respiratory systemsystem

Special conditionsSpecial conditions

Exercise at Exercise at high altitudeshigh altitudes

Exercise under Exercise under very hot very hot

conditionsconditions

Changes In Ventilation During ExerciseChanges In Ventilation During Exercise

The pOThe pO2 2 of arterial of arterial blood drops from blood drops from 40mm to <25mm 40mm to <25mm

HgHg

Blood flow per min Blood flow per min rises from 5.5 L/min rises from 5.5 L/min

to 20-35 L/minto 20-35 L/min

Recruitment of Recruitment of new capillaries at new capillaries at

tissue leveltissue level

Increased Increased OO22 delivery delivery to tissuesto tissues

Ventilation Ventilation

Increases abruptly with the Increases abruptly with the onset of exercise onset of exercise

More gradual increase.More gradual increase.

Arterial blood gases during Arterial blood gases during exerciseexercise

Increase in Increase in ventilationventilation

Increased Increased oxygen oxygen demanddemand

Increased Increased body body

temperaturetemperature

Increased Increased plasma plasma

potassium potassium levelslevels

Increased Increased neural neural

sensitivity to sensitivity to partial pressure partial pressure

of COof CO22

Increased Increased plasma Hplasma H++

ion ion concentrationconcentration

Role of ORole of O22??????

Mainly shows Mainly shows increase in increase in

both rate and both rate and depth of depth of

respirationrespiration

Mainly shows Mainly shows increase in increase in

depth of depth of respirationrespiration

ExerciseExercise

Moderate Moderate exerciseexercise

Severe Severe exerciseexercise

Ventilation and heart rate with Ventilation and heart rate with exerciseexercise

Oxygen DebtOxygen Debt

Replenishment Replenishment of ATPof ATP

Removal of Removal of lactic acidlactic acid

Replenishment Replenishment of myoglobin of myoglobin

with Owith O22

Replenishment Replenishment of glycogenof glycogen

VEN

TIL

ATIO

N R

ATE

VEN

TIL

ATIO

N R

ATE

Excess Post-exercise Oxygen Excess Post-exercise Oxygen ConsumptionConsumption

Oxygen Diffusing CapacityOxygen Diffusing Capacity

Fick’s law of diffusionFick’s law of diffusion

V gas =A/T x D x (P1 – P2) V gas =A/T x D x (P1 – P2) V gas = rate of diffusionV gas = rate of diffusion

A = tissue areaA = tissue areaT = tissue thicknessT = tissue thicknessD = diffusion coefficient of gasD = diffusion coefficient of gasP1 – P2 = difference in partial pressureP1 – P2 = difference in partial pressure

Maximal OMaximal O2 2 diffusing capacity of diffusing capacity of

different personsdifferent personsNonathlete at rest Nonathlete at rest 23 mL/min23 mL/min

Nonathlete during maximal exercise Nonathlete during maximal exercise 48 mL/min48 mL/min

Speed skaters during maximal Speed skaters during maximal exercise exercise

64 mL/min64 mL/min

Swimmers during maximal exercise Swimmers during maximal exercise 71 mL/min71 mL/min

Oarsman during maximal exercise Oarsman during maximal exercise 80 mL/min80 mL/min

Maximal ExerciseMaximal Exercise

Increased blood flow through the lungsIncreased blood flow through the lungs

All the pulmonary capillaries are perfused at All the pulmonary capillaries are perfused at their maximal rates their maximal rates

A far greater surface area available through A far greater surface area available through which oxygen can diffuse into the pulmonary which oxygen can diffuse into the pulmonary

capillary bloodcapillary blood

Increased diffusion Increased diffusion capacity of Ocapacity of O22

Oxygen-Haemoglobin Dissociation Oxygen-Haemoglobin Dissociation Curve in ExerciseCurve in Exercise

...................... CURVE CURVE

IN IN EXERCISEEXERCISE

………………..NORMAL NORMAL CURVECURVE

Fatigue of respiratory musclesFatigue of respiratory muscles

Do respiratory muscles fatigue during Do respiratory muscles fatigue during exercise?exercise?

Yes they do!!!Yes they do!!!

Effect of Smoking on Pulmonary Effect of Smoking on Pulmonary Ventilation in ExerciseVentilation in Exercise

SMOKING (Nicotine and other irritants)SMOKING (Nicotine and other irritants)

Constriction of Constriction of the terminal the terminal bronchiolesbronchioles

IncreasesIncreases the the resistance of resistance of

airflow airflow

Increased fluid Increased fluid secretion and mucosal secretion and mucosal

oedemaoedema

Paralyses the mucociliary Paralyses the mucociliary escalator systemescalator system

Increased Airway Increased Airway ResistanceResistance

Decreased Decreased expiratory flowexpiratory flow

Chronic smokingChronic smoking

Chronic Obstructive Pulmonary Chronic Obstructive Pulmonary Disease (COPD)Disease (COPD)

COPDCOPD

Chronic bronchitisChronic bronchitis(Excessive mucous (Excessive mucous

blocks airways)blocks airways)

EmphysemaEmphysema(Dilatation of alveolar (Dilatation of alveolar

sacs, airway collapse and sacs, airway collapse and increased resistance)increased resistance)

Smoking is equivalent to suicide…Smoking is equivalent to suicide…

Please try to quit smoking…Please try to quit smoking…

THANK YOUTHANK YOU