BR / TV / MV Flashcards
What letters represent breathing rate, tidal volume and minute ventilation?
F, TV, VE
Define ‘breathing rate’
Number of inspirations or expirations per minute
Define ‘tidal volume’
Volume of air inspired or expired per breath
Define ‘minute ventilation’
The volume of air expired per minute
How is minute ventilation calculated?
Tidal volume x breathing rate
What is the average resting breathing rate?
12-15
What is the average resting minute ventilation?
6-7.5l/min
What is the average resting tidal volume?
500ml
What is meant by the term ‘dead space’?
The volume of air inhaled that is not involved in gaseous exchange because it remains in conducting airways or reaches poorly perfused alveoli
How does minute ventilation respond to sub-maximal exercise and why?
As intensity increases so does VE but plateaus as the performer reaches a steady state to supply oxygen demand
How does tidal volume respond to sub maximal exercise and why?
Increases linearly with exercise intensity up to 3l but plateaus at sub max because there is not enough time to inspire and exhale efficiently
For a trained performer at maximal intensity, what is their average breathing rate?
50-60
For a trained performer at max intensity, what is their average minute ventilation?
169-210l/min
For a trained performer at max intensity, what is their average tidal volume?
3-3.5l
For an untrained performer at max intensity, what is their average breathing rate?
40-50
