adaptation of the respiratory system to long term of exercise

1. Respiratory
Adaptations
Dr. Khaled Alkhodary

2. Long-term effects of
exercise on the
respiratory system
The muscles demand
more oxygen and as
a result more CO2 is
produced. To combat
this the body adapts
by:

3. 3. Increased
strength of
the
respiratory
muscles
1-
Increased
Lung
Ventilation
2. Increase
lung
capacity
4.
Capillaries
in the lung
5.
Alveoli
6. Gas
Exchange
7. VO2
MAX

4.  In lower intensity exercise due to increase
in tidal volume
 In a higher intensity exercise due to tidal
volume and increase in breathing rate
1- Increased
Lung
Ventilation

5.  Increase the tidal volume: (tidal volume is the volume of air
moved between one normal inhalation and one normal exhalation)
Receptors in blood vessels sense the arterial blood
concentration of H+ and CO2 signal the brain to change
breathing depth to suit the demands of the activity, and the
body will adapt naturally with a higher normal tidal volume .
 Decrease of the inspiratory reserve volume and
expiratory reserve volume

6. Average Normal Values of tidal
volume :
normal breathing 500 ML
in exercise 1000 ML
in athletes 2000 ML

7.  Increase in breathing rate : this is more an
adaptation from anaerobic fitness and muscular
endurance training or higher intensity aerobic fitness
training . This enables more air to move in and out of the
lungs enhancing gas exchange

8.  this increase can begin even before exercise starts.
It is thought to be the result of a central neural
command initiated by the respiratory control center
located in the brain. The response serves as a feed-
forward signal to assist in meeting the future energy
needs of muscle contraction.

9.  Lungs increase their ability to expand enabling a
greater quantity of air to move in and out (this is
a similar adaptation to the increase in stroke
volume in the cardiovascular system).
2. Increase
lung
capacity:

10.  The diaphragm and intercostal muscles increase in
strength. This allows for greater expansion of the thoracic
(chest) cavity.
 This results in an improved ability to breathe in more air,
for longer with less fatigue .
 Aerobic training tends to improve the endurance of respiratory muscles
 Anaerobic training tends to increase the size and strength of respiratory muscles
3. Increased
strength of the
respiratory
muscles :

11.  Increase number and size of capillaries in the
lungs over time allowing more blood to flow in
and out of the lungs. This improves the uptake of
oxygen as there is a greater surface area for
blood to bind with hemoglobin .
4.
Capillaries
in the lung
:

12.  The numbers of alveoli in the lungs
increase to enable more gas exchange to
occur.
5.
Alveoli :

13.  The exchange of oxygen and carbon dioxide improves as
the gradient between each becomes larger. This occurs
because the more oxygen used in the tissues and the more
carbon dioxide produced creates a larger
difference/gradient between the blood and tissues.
6. Gas
Exchange
:

14.  Aerobic fitness training tends to improve the efficiency of
the body’s tissues at absorbing O2 and removing CO2, while
anaerobic fitness and muscular endurance training tends to
improve the capacity for this gas exchange

15.  VO2 MAX is improved as a result of aerobic training – it can be
improved between 5 to 30 %.
 Improvements are a result of:
 -Increases in cardiac output
 -Increased Red blood cell numbers
 - Increased muscle and alveoli capillarisation
 - Increased gaseous exchange
 - More O2 coming in and being used
 - More CO2 leaving the blood and the body
 - Greater oxygen extraction by muscles
7. Increased
Maximum
Oxygen Uptake
(VO2 MAX)

16. 8. Increased Anaerobic or Lactate
Threshold :
 As a result of improved O2 delivery & utilisation a higher
lactate threshold (the point where O2 supply cannot keep
up with O2 demand) is developed.
 Much higher exercise intensities can therefore be reached
and LA (lactic acid) and H+ ion accumulation is delayed.
The athlete can work harder for longer