f, TV, VE and its response to exercise

Question 1

What is the symbol for breathing rate?

Answer 1

f

Question 2

What is the average resting breathing rate?

Answer 2

12-15 breaths

Question 3

Definition of breathing rate

Answer 3

The number of inspirations or expirations (breaths) per minute

Question 4

What is the symbol to represent tidal volume?

Answer 4

TV

Question 5

What is the average resting tidal volume?

Answer 5

500ml

Question 6

Definition of tidal volume

Answer 6

The volume of air inspired or expired per breath

Question 7

What is the piece of equipment used to measure lung volumes?

Answer 7

Spirometer

Question 8

What is the symbol used for minute ventilation?

Answer 8

VE

Question 9

What is the equation to calculate minute ventilation?

Answer 9

VE = TV x f

Question 10

Definition of minute ventilation?

Answer 10

The volume of air inspired or expired per minute

Question 11

What is the average resting minute ventilation?

Answer 11

6-7.5 l/min

Question 12

Why may an aerobic athletes VE be lower?

Answer 12

They have more efficient gaseous exchange and transport, they can meet the demands for oxygen more efficiently at rest

Question 13

What is the comparison of values of f, TV and VE for an untrained and trained athlete at rest

Question 14

What is breathing rate response to exercise?

Answer 14

-Increases in proportion to exercise intensity
-Increases to about 40-50 breaths per minute for untrained, 50-60 per minute for training
-Can plateau once demand is met in sub-maximal work

Question 15

What is TV response to exercise?

Answer 15

-Increases in line with exercise intensity (up to 3 litres)
-Plateaus at sub-maximal intensity as demand is met

Question 16

What is the values of TV at maximal intensity exercise for a trained and untrained performer?

Answer 16

Untrained - 2.5-3l
Trained - 3-3.5l

Question 17

What is minute ventilation response to exercise?

Answer 17

-Increases in line with exercise intensity
-During sustained sub-maximal work VE can plateau, this represent oxygen demand and waste removal being met
-TV will reach its capacity but breathing frequency will continue to increase

Question 18

What is the values of VE at maximal intensity exercise for a trained and untrained performer?

Answer 18

Untrained - 100-150 l/min
Trained - 160-210 l/min

Question 19

What is the values of f at maximal intensity exercise for a trained and untrained performer?

Answer 19

Untrained - 40-50
Trained - 50-60

Question 20

Explain according to the graph the response of VE to light exercise intensity?

Answer 20

1. an anticipatory rise in VE prior to exercise due to release of hormone adrenaline
2. a rapid increase in VE at the start of exercise due to increased breathing frequency and tidal volume to increase oxygen delivery and waste removal in line with exercise intensity
3. A steady state VE throughout the sustained intensity exercise as oxygen supply meets demand
4. An initial rapid and then more gradual decrease in VE to resting levels as recovery is entered and oxygen demand dramatically reduces

Question 21

What is the different in VE for light and maximal intensity exercise?

Answer 21

-During maximal intensity, VE does not plateau as exercise intensity continues to increase, growing demand for oxygen and waste removal which VE must meet
-There will be a rapid decrease followed by a more gradual decrease in heavy-intensity exercise

Question 22

What are the mechanics of inspiration at rest?

Answer 22

-Active process
-External intercostals muscles contract lifting the ribs up and out (internal intercostals relax)
-Diaphragm contracts and flattens
-Volume inside the thoracic cavity increases
-This lowers the pressure below atmospheric air pressure and forces air into lungs
-As gases move form a high pressure to low pressure

Question 23

What are the mechanics of expiration at rest?

Answer 23

-Passive process
-External intercostals muscles relax, ribcage and sternum move in and down
-Diaphragm relaxes, returns to dome shape
-Decreased size of thoracic cavity
-Pressure increases above atmospheric air, so air is forced out of lungs

Question 24

What are the mechanics of inspiration during exercise?

Answer 24

-Active process
-More muscles are recruited to increase breathing rate, more forceful contractions
-Sternocleidomastoid recruited, contracts to lift the sternum
-Pectorialis major recruited, contracts to life ribs more
-External intercostal muscles contract with more forceful contractions, whole internal intercostals relax, ribs move up and out more
-Volume of thoracic cavity increases more, pressure decreases more, larger concentration gradient, air enters lungs quicker

Question 25

What are the mechanics of expiration during exercise?

Answer 25

-Active process -Change from passive to active process due to increase depth and frequency of breathing during exercise -External intercostal muscles relax -Internal intercostals contract, pulls ribs down and in -Diaphragm relaxes -Rectus abdominus contracts, push diaphragm up with more forces -Volume of thoracic cavity decreases more, increase in pressure above atmospheric pressure, larger concentration gradient, air forced out of lungs quicker