Respiration during exercise

ventilation

mechanical process of moving air into and out of the lungs

diffusion

random movement of molecules from an area of high concentration to low concentration

alveolar gas exchange

movement of respiratory gases between alveolar region and blood

systemic gas echange

diffusion of respiratorry gases from the blood into the cells

alveoli

site of gas exchange

visceral pleura

membrane on outer surface of lung

parietal pleura

membrane lining thoracic wall

conducting zone parts

trachea, bronchial tree, bronchioles

conducting zone function

moves air to respiratory zone and humidifies and warms air

respiratory zone parts

respiratory bronchioles and alevolar sacs

surfactant

prevents alveolar collapse

inspiration accessory muscles

sternoclediomastoid, scalenes, pec minor

expiration accessory muscles

abdominals, internal intercostals

intraplural pressure decreases

volume of lungs increases

intraplural pressure decreases

lung volume decreases

intralveolar pressure vs intraplural pressure

keeps lungs from collapsing

fatigues respiratory muscles

prolonged exercise and high intensity training

airflow=

(P1-P2) / resistance

main factor of resistance in airway

radius of airway

tidal volume

amount of air moved per breath

breathing frequency

breaths per minute

alveolar ventilation

volume of air that reaches respiratory zone

dead-space ventilation (anatomical)

volume of air remaining in conducting airways

vital capacity

max gas that can be expired after max inspiration

residual volume

volume of gas remaining in lungs after max exhalation

total lung capacity

amount of gas in lungs after max inspiration

VC =

TV+IRV+ERV

forced expiratory volume

volume of air expired during 1 second during max exhalation

healthy FEV/VC ratio

>80%

barometric pressure at sea level

760 mmHg

rest fresh PPO2

159

rest fresh PPCO2

0.3

rest alveolar PPO2

104

rest alveolar PPCO2

40

rest deoxygenated PPO2

40

rest deolxygenated PPCO2

46

rest oxygenated PPO2

95

rest oxygenated PPCO2

40

rest tissue PPO2

40

rest tissue PPCO2

46

lower pressure in pulmonary due to

lower vascular resistance

standing at rest

most blood to base of lungs

blood flow during exercise

more blood to apex of lungs

V/Q at apexof lung

>1 underperfused

V/Q at base of lung

<1 overperfused

V/Q with heavy exercise

missmatch ratio due to lack of time

1 gram Hb

1.34ml O2

O2 transported bound to Hb

99%

4 O2

per 1 Hb

lungs

high PO2

tissues

low PO2

O2 usage at rest

25%

O2 usage during exercise

90%

% HbO2 sat arteries at rest

98%

% HbO2 sat veins at rest

75%

shift O2Hb curve right

pH, temp, 2-3 DPG

myoglobin

shuttles O2 from cell membrane to mitochondria

CO2 dissolves in plasma

10%

CO2 bound to Hb

20%

CO2 as bicarbonate

70%

carbonic anhydrase

involved in formation of bicarbonate

VT

point where breath efficiency is sacrificed for overall capacity

prebotzinger complex

main driver of rhythm

retrotrapezoidal nucleus, pneumotaxic center, and caudal pons

fine tuning of respiration

inspiration

contraction of diaphragm

expiration

passive recoil of lungs

humoral chemoreceptors

central (medulla) and peripheral (aortic & carotid bodies)

nueral input

motor cortex and skeletal muscle receptors

driving urge to take a breath

CO2

hypoxic threshold

65 mmHg

arterial PCO2

linear increase w intensity