Pulmonary ventilation (5)

Question 1

tidal volume

Answer 1

air moved during the inspiratory or expiratory phase of each breathing cycle (.4-1L)

Question 2

inspiratory reserve volume

Answer 2

inspiring as deeply as possible following a normal inspiration

Question 3

expiratory reserve volume

Answer 3

after a normal exhalation, continuing to exhale and forcing as much air as possible from the lungs

Question 4

forced vital capacity

Answer 4

total volume of air voluntarily moved in one maximal breath, it includes TV plus IRV and ERV

Question 5

residual lung volume

Answer 5

air volume remaining after a forced maximal exhalation
allows an interruption exchange of gas between the blood and alveoli to prevent fluctuations in blood gases during phases of the breathing cycle

Question 6

RLV + FVC =

Answer 6

total lung capacity

Question 7

forced expiratory volume (FEV)

Answer 7

maximal airflow measured over 1s

Question 8

valsalva maneuver

Answer 8

closing glottis following a full inspiration while maximally activating expiratoruu muscles, creating compressive forces that increase intrathoracic pressure above atmospheric pressure

Question 9

physiologic consequences of performing the valsalva maneuver

Answer 9

performing a prolonged one during static, straining-type exercise dramatically reduces venous return and arterial blood pressure
diminishes brain’s blood supply, producing dizziness or fainting

Question 10

Arteriovenous Oxygen Difference`

Answer 10

the difference between oxygen content of arterial blood and mixed-venous blood

Question 11

as the body engages in intense aerobic exercises, venous O2 content

Answer 11

decreases in order to supply tissues with more oxygen

Question 12

what limits aerobic capacity?

Answer 12

oxygen supply, not muscle oxygen use

Question 13

a small increase in PCO2 in inspired air triggers

Answer 13

a large increase in minute ventilation

Question 14

during light to moderate exercise, VE

Answer 14

increases linearly with Vo2 and vCO2

Question 15

ventilatory threshold

Answer 15

point where pulmonary VE increases disproportionately to VO2 during graded exercise

Question 16

lactate threshold

Answer 16

highest VO2 or exercise intensity before a 1.0 mM increase in blood lactate concentration above the pre-exercise level

Question 17

onset blood lactate accumulation

Answer 17

when blood lactate concentration systemically increases to 4mM

Question 18

3 reasons to measure LT

Answer 18

1. sensitive indicator of aerobic training status
2. predicts endurance performance, often with greater accuracy than VO2 max
3. establishes effective training intensity geared to active muscles’ aerobic metabolic dynamics