Lung Volumes and
Capacities
Learning Objectives
 Be familiar with the concepts of, and be able to measure
lung volumes and capacities.
 Understand the concepts of minute ventilation, tidal volume
and ventilation rates during quiet breathing and during
exercise.
 Account for the differences in lung volumes and capacities
between untrained and trained sportspersons.
Lung Volumes
 During normal quiet breathing, we inspire approximately 500ml of
air. The same amount is exhaled during the process of expiration.
 The volume of air inspired and expired is known as TIDAL
VOLUME.
 Of this 500ml, only about 350ml makes its way into the alveoli. The
other 150ml remains in the passageways of the nose, throat and
trachea and is known as dead space.
 The volume of air which is inspired or expired in one minute is
called MINUTE VENTILATION and is calculated by multiplying tidal
volume by the number of breaths taken per minute.
 On average we breathe 12 to 15 times per minute, so our
resting minute ventilation can be calculated as follows:
 VE = T.V x f
= 500ml x 15
= 7,500ml/min (7.51/min)
Lung volume Capacity
Definition
Approximate normal values (ml)
Changes during exercise
Tidal volume (TV)
Volume inspired or expired per
breath
500
Increases up to 3-4 litres
Inspiratory reserve volume (IRV)
Maximal volume inspired from
end inspiration
3,300
Decreases
Expiratory reserve volume
(ERV)
Maximal volume expired from
end expiration
1,000-1,200
Slight decrease
Residual volume (RV)
Volume remaining at end of
maximal expiration
1,200
Slight increase
Total Lung Capacity (TLC)
Volume in lung at end of
maximal inspiration
Up to 8,000
Slight decrease
Vital Capacity (VC)
Maximal volume forcefully
expired after maximal
inspiration
5,500
Slight decrease
Inspiratory capacity (IC)
Maximal volume inspired from
resting expiratory level
3,800
Increase
Functional residual capacity
(FRC)
Volume in lungs at resting
expiratory level
2,400
Slight increase
Dead space
Volume of air in the trachea etc
that does not take part in
gaseous exchange
150
None
Minute ventilation
Volume of air inspired/ expired
per minute
TE= TV x F
7,500
Large increase (200L/min) in
trained athletes
Ventilation during exercise
 When we exercise depth and rate of breathing
increases
 Tidal volume increases by using Inspiratory reserve
volume and expiratory reserve volume.
 These volumes decrease, while tidal volume
increases- up to 6 x
 Minute ventilation increases
Tidal Volume
(TV) x
frequency
(breaths/min)
= minute
ventilation
Rest
500ml (0.5L) x
15
=7.5L/min
Maximal work
4,000 (4.0L) x
50
= 200L/min
Ventilation during exercise
 Changes in ventilation occur before exercise
begins
Anticipatory rise
 Result of hormones, stimulating the respiratory
centre- adrenaline
 Once we start to exercise there is a rapid rise in
ventilation due to nervous stimulation
 Sub max exercise- this slows down and steady
state is reached
 Maximal exercise- ventilation increases until
exercise is finished.
Ventilation during exercise
 If intensity continues to rise to a point near
the athletes VO2 max (maximum amount of
oxygen that can be taken in, transported
and utilised in one minute) is reached, they
cant get enough oxygen to working muscles
so will have to slow down or stop.
Recovery…
 During recovery- ventilation drop
rapidly at first followed by a
slower decrease
 More intense the preceding
exercise- longer the recovery
 Removal of lactic acid
Guess Who??




Choose from one of the key words from today's lesson.
Write it on the post it note and stick to your partners head.
They have to guess which key word they are by asking questions
You are only allowed to answer ‘Yes’ or ‘No’
 Tidal volume (TV)
 Inspiratory reserve volume (IRV)
 Expiratory reserve volume (ERV)
 Residual volume (RV)
 Total Lung Capacity (TLC)
 Vital Capacity (VC)
 Inspiratory capacity (IC)
 Functional residual capacity (FRC)
 Dead space
 Minute ventilation
 Steady state
 VO2 max
 Anticipatory rise
 Adrenaline
 Spirometer