16. McArdle ch. 12

Question 1

what is tidal volume? (Vt)

Answer 1

volume of air inspired or expired with each normal breath.

Question 2

what is inspiratory reserve volume(IRV)?

Answer 2

extra volume of air that can be forcefully inspired over and above VT.

Question 3

what is expiratory reserve volume(ERV)?

Answer 3

maximum extra volume of air that can be forcefully expired over and above VT.

Question 4

what is residual volume(RV)?

Answer 4

volume of air remaining in lungs after forceful expiration.

Question 5

what does residual lung volume allow for?

Answer 5

Allows an uninterrupted exchange of gas between the blood and alveoli, which prevents fluctuations in blood gases during phases of the breathing cycle

Question 6

how does residual lung volume increase temporarily?

Answer 6

increases from an acute bout of either short-term or prolonged exercise due to:

• Closure of the small peripheral airways
• Increase in thoracic blood volume

Question 7

what are the 4 pulmonary capacities?

Answer 7

• inspiration capacity(IC)
• functional residual capacity(FRC)
• forced vital capacity(FVC)?
• total lung capacity(TLC)

Question 8

what is inspiration capacity(IC)?

Answer 8

maximum amount of air that can be inspired from end of normal expiration (= VT + IRV).

Question 9

what is functional residual capacity(FRC)?

Answer 9

amount of air remaining in lungs after normal expiration (= ERV + RV).

Question 10

what is forced vital capacity(FVC)?

Answer 10

maximum amount of air that can be forcefully inspired and expired (= IRV + VT+ ERV).

Question 11

what is total lung capacity(TLC)?

Answer 11

maximum amount of air comprised in the lungs (= IRV + VT + ERV + RV).

Question 12

what doe dynamic ventilation depend on?

Answer 12

-Maximum “stroke volume” of the lungs (FVC)
-Speed of moving a volume of air (breathing rate):
which is Determined by lung compliance, or the resistance of the respiratory passages to air and the “stiffness” imposed by the chest and lung

Question 13

what does max voluntary ventilation evaluate?

Answer 13

-Evaluates ventilatory capacity with rapid and deep breathing for 15 seconds
:Extrapolated to the volume if the subject continued for 1 minute

Question 14

what is the gender difference in lung measures?

Answer 14

women have a reduced lung size and airway diameter, a smaller diffusion surface and static and dynamic lung function measures

Question 15

what does a smaller lung size lead to in women?

Answer 15

This leads to expiratory flow limitations, greater respiratory muscle work and use of ventilatory reserve during maximal exercise, particularly in highly trained women

Question 16

Does regular endurance exercise stimulate large increases in the functional capacity of the pulmonary system?

Answer 16

Regular endurance exercise does not stimulate large increases in the functional capacity of the pulmonary system

Question 17

Dynamic lung function tests indicate the severity of obstructive and restrictive lung diseases, but provide _____ information about aerobic fitness or exercise performance when values fall within the normal range

Answer 17

little info

Question 18

how can minute ventilation be increased?

Answer 18

by an increase in the rate or depth of breathing, or both

Question 19

In moderate exercise, well-trained athletes maintain alveolar ventilation by increasing ____ with only a small increase in breathing rate

Answer 19

tidal volume

Question 20

true or false? Attempts to modify breathing during running or other general physical activities offer no benefit to exercise performance

Answer 20

true

Question 21

what is the ventilation/perfusion ratio?

Answer 21

the ratio of alveolar ventilation to pulmonary blood flow

avg=0.84 ratio

Question 22

what is anatomical dead space?

Answer 22

anatomical structures of the respiratory system that are not directly involved in gas exchange, generally ranges between 150-200 mL

Question 23

what is physiological dead space

Answer 23

The portion of the alveolar volume with a ventilation–perfusion ratio that approaches zero:
the alveoli may not function adequately in gas exchange because of:
-Underperfusion of blood
-Inadequate ventilation relative to the alveolar surface

Question 24

In certain pathologic situations, physiologic dead space increases to ___% of the tidal volume

Answer 24

50%

Question 25

Adequate gas exchange becomes _____ when the dead space of the lung exceeds ___% of total lung volume

Answer 25

impossible

60%

Question 26

what is Hyperventilation?

Answer 26

An increase in pulmonary ventilation that exceeds the O2 consumption and CO2 elimination needs of metabolism

Question 27

what is Dyspnea?

Answer 27

An inordinate shortness of breath or subjective distress in breathing

Question 28

what is valsalva maneuver?

Answer 28

Closing the glottis following a full inspiration while maximally activating the expiratory muscles, creating compressive forces that increase intrathoracic pressure above atmospheric pressure

Question 29

what is the physiological consequence of performing the valsalva maneuver?

Answer 29

Performing a prolonged Valsalva maneuver during static, straining-type exercise dramatically reduces venous return and arterial blood pressure
which:
-This diminishes the brain’s blood supply, often producing dizziness or fainting
-Once the glottis reopens and intrathoracic pressure normalizes, blood flow reestablishes with an “overshoot” in arterial blood pressure