Transcript File - margolis sport exercise

IB
Sports,
exercise and
health science
Exercise physiology
2.1.1 List the principal structures of the
ventilatory system
Topic 2
Exercise
Physiology
Sub-topics
1. Structure &
function of the
ventilatory
system
2. Structure &
function of the
cardiovascular
system

The principle structures of the respiratory system
are:
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Nose/Mouth
Pharynx
Larynx: voice box
Trachea
Bronchi
Bronchioles
Lungs
Alveoli
IB
Sports,
exercise and
health science
Topic 2
Exercise
Physiology
Exercise physiology
2.1.1 List the principal structures of the
ventilatory system
Sub-topics
1. Structure &
function of the
ventilatory
system
2. Structure &
function of the
cardiovascular
system
http://www.umm.edu/respiratory/images/respiratory_anatomy.jpg
IB
Sports,
exercise and
health science
Exercise physiology
2.1.1 List the principal structures of the
ventilatory system
Topic 2
Exercise
Physiology
Sub-topics
1. Structure &
function of the
ventilatory
system
2. Structure &
function of the
cardiovascular
system


Smooth muscle tissue is found on the walls of
some of our internal hollow organs It produces
smooth, rhythmical actions.
We can not consciously control the action of
smooth muscle. It is subsequently termed
involuntary.
e.g. movement of blood and air in the lungs
DET PDHPE Distance Education Programme
IB
Sports,
exercise and
health science
Exercise physiology
2.1.1 List the principal structures of the
ventilatory system
Topic 2
Exercise
Physiology
Sub-topics

1. Structure &
function of the
ventilatory
system
2. Structure &
function of the
cardiovascular
system

The trachea is a thin walled tube about the
diameter of an average garden hose. It is
composed of very thin, tough connective tissue
and is strengthened at intervals by incomplete
rings of cartilage.
The trachea muscle runs down the posterior wall
of the trachea. This is an example of smooth
muscle.
Solomon & Davis
IB
Sports,
exercise and
health science
Topic 2
Exercise
Physiology
Exercise physiology
2.1.2 Outline the functions of the conducting
airways
Sub-topics

1. Structure &
function of the
ventilatory
system
2. Structure &
function of the
cardiovascular
system
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The nostrils are fringed with coarse hair, which
strains large particles out of the airstream and may
also serve to protect the nasal cavity from invasion
by insects.
The interior of the nasal cavity contains projections
of considerable surface area. These projections,
nasal conchae, make the airstream turbulent and
subsequently warm and hydrate it.
Thanks to the structure of the nose, air entering the
trachea is virtually 100% humidified.
Solomon & Davis
IB
Sports,
exercise and
health science
Topic 2
Exercise
Physiology
Exercise physiology
2.1.2 Outline the functions of the conducting
airways
Sub-topics
1. Structure &
function of the
ventilatory
system
2. Structure &
function of the
cardiovascular
system
www.nlm.nih.gov
IB
Sports,
exercise and
health science
Topic 2
Exercise
Physiology
Sub-topics
1. Structure &
function of the
ventilatory
system
2. Structure &
function of the
cardiovascular
system
Exercise physiology
2.1.2 Outline the functions of the conducting
airways
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Air passes through the 3 portions of the pharynx,
which provides a low resistance path for airflow, to
the trachea via the larynx.
In addition to it’s function as the voice box the larynx
protects the trachea from invasion by foods and
fluids.
The cartilaginous trachea, branches into the two
main bronchi.
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The lining of the tracheobronchial system is designed
to protect the lungs from dehydration and invasion by
foreign particles, including micro-organisms.
Solomon & Davis
IB
Sports,
exercise and
health science
Topic 2
Exercise
Physiology
Exercise physiology
2.1.2 Outline the functions of the conducting
airways
Sub-topics

1. Structure &
function of the
ventilatory
system
2. Structure &
function of the
cardiovascular
system

The lungs themselves develop at the end of the
bronchi. They are elastic spongy organs.
Gas exchange is carried out by a complex of
structures at the end of each terminal bronchioles.
They are simple thin walled structures which also
have numerous thin-walled outpocketings called
alveoli, which are specialised for the function of
gaseous exchange.
Solomon & Davis
IB
Sports,
exercise and
health science
Topic 2
Exercise
Physiology
Exercise physiology
2.1.3 Define respiratory terms
Sub-topics
1. Structure &
function of the
ventilatory
system
2. Structure &
function of the
cardiovascular
system

Pulmonary ventilation: is commonly referred to as
breathing. It is the process of air flowing into the
lungs during inspiration (inhalation) and out of the
lungs during expiration (exhalation). Air flows
because of pressure differences between the
atmosphere and gases inside the lungs.
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DET PDHPE Distance Education Programme
IB
Sports,
exercise and
health science
Topic 2
Exercise
Physiology
Sub-topics
1. Structure &
function of the
ventilatory
system
2. Structure &
function of the
cardiovascular
system
Exercise physiology
2.1.3 Define respiratory terms
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Air, like other gases, flows from a region with higher
pressure to a region with lower pressure. Muscular
breathing movements and recoil of elastic tissues create
the changes in pressure that result in ventilation.
Pulmonary ventilation involves three different pressures:
• Atmospheric pressure
• Intraalveolar (intrapulmonary) pressure
• Intrapleural pressure
Atmospheric pressure is the pressure of the air outside the
body. Intraalveolar pressure is the pressure inside the
alveoli of the lungs. Intrapleural pressure is the pressure
within the pleural cavity. These three pressures are
responsible for pulmonary ventilation.
http://training.seer.cancer.gov/module_anatomy/unit9_2_resp_vent_mechanics.html
IB
Sports,
exercise and
health science
Topic 2
Exercise
Physiology
Exercise physiology
2.1.3 Define respiratory terms
It is important to understand the various volumes
and capacities of the lungs in order to appreciate the
effects of exercise on the respiratory system.
Sub-topics
1. Structure &
function of the
ventilatory
system
2. Structure &
function of the
cardiovascular
system
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Total lung capacity can be calculated by adding vital
capacity to residual volume of the lungs.
During normal, quiet respiration, about 500mL of air
is inspired. The same amount of air moves out with
expiration. This volume of air is called the tidal
volume.
When we forcibly take a deep breath, we can take in
up to 3100mL above the tidal volume. This additional
air is the inspiratory reserve volume.
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Browne et. al 2001
IB
Sports,
exercise and
health science
Topic 2
Exercise
Physiology
Exercise physiology
2.1.3 Define respiratory terms
Sub-topics

1. Structure &
function of the
ventilatory
system
2. Structure &
function of the
cardiovascular
system

We can also forcibly exhale. This is termed the
expiratory reserve volume.
Even after the expiratory reserve volume is expelled,
some air is still trapped in the lungs because of
pressure. This is called the residual volume.

DET PDHPE Distance Education Programme
Browne et al 2001
IB
Sports,
exercise and
health science
Topic 2
Exercise
Physiology
Exercise physiology
2.1.4 Explain the mechanics of ventilation in
the human lungs
Sub-topics
1. Structure &
function of the
ventilatory
system
2. Structure &
function of the
cardiovascular
system
To understand how a person breathes, you need to know that
a substance called pleural fluid lies between the lungs and the
chest wall.
Have you ever put two pieces of wet glass together (e.g.
microscope slides) and found that you could not easily pull
them apart. This phenomenon results from a combination of
forces – surface tension, molecular cohesion and atmospheric
pressure.
Solomon & Davis
IB
Sports,
exercise and
health science
Topic 2
Exercise
Physiology
Sub-topics
1. Structure &
function of the
ventilatory
system
2. Structure &
function of the
cardiovascular
system
Exercise physiology
2.1.4 Explain the mechanics of ventilation in
the human lungs
Think of the walls of the chest and the lungs as the two wet
slides and the pleural fluid as the film of water. When the
chest expands during breathing, the film of pleural fluid
causes the membranous walls of the lungs to be pulled
outward along with the chest walls. This means the space
within the lungs increases. The air molecules in the lungs now
move momentarily farther apart, so that the pressure in of
the air in the lungs falls below the pressure of the atmosphere
outside the body.
Consequently, air from outside rushes down the trachea and
into the lungs until the two pressures are equal again. This is
the process of inspiration.
Solomon & Davis
IB
Sports,
exercise and
health science
Topic 2
Exercise
Physiology
Sub-topics
1. Structure &
function of the
ventilatory
system
2. Structure &
function of the
cardiovascular
system
Exercise physiology
2.1.4 Explain the mechanics of ventilation in
the human lungs
Observation of the skeleton reveals that each rib pivots
about a vertebral joint. If it is lifted upward it also
swings outward, with the thoracic cavity being enlarged
anteriorly and superiorly. This is the task in quiet
breathing of the external intercostal muscles.
At the same time the ribs are lifted, the diaphragm (the
muscular floor of the thoracic cavity) contracts
downward enlarging the thoracic cavity inferiorly. This
process enlarges the cavity twofold.
Solomon & Davis
IB
Sports,
exercise and
health science
Topic 2
Exercise
Physiology
Exercise physiology
2.1.4 Explain the mechanics of ventilation in
the human lungs
Sub-topics
1. Structure &
function of the
ventilatory
system
2. Structure &
function of the
cardiovascular
system
Expiration is almost entirely a passive process that
depends on the elasticity of the lungs and chest
structures, as well as fluid film surface tensions within
the lungs. When inspiratory muscles are relaxed, air
simply leaves the lung, much as it would leave an
untied balloon.
Solomon & Davis
IB
Sports,
exercise and
health science
Exercise physiology
2.1.4 Explain the mechanics of ventilation in
the human lungs
Topic 2
Exercise
Physiology
Sub-topics

1. Structure &
function of the
ventilatory
system
2. Structure &
function of the
cardiovascular
system

This above description is for quiet breathing. When one
speaks or runs, the abdominal muscles press upon the
abdominal contents, squeezing them upwards against
the diaphragm. The internal intercostal muscles oppose
the external intercostals and pull the ribcage
downward, helping to decrease the thoracic cavity
volume and forcibly empty the lungs. The diaphragm
may also function in forcible expiration.
In laboured inspiration (e.g. accompanying exercise)
many of the muscles of the upper trunk are also
recruited. They are only indirectly attached to the ribs
and are inefficient as respiratory muscles. E.g.
Pectoralis major and minor, Trapezius, Rhomboideus.
Solomon & Davis
IB
Sports,
exercise and
health science
Topic 2
Exercise
Physiology
Exercise physiology
2.1.4 Explain the mechanics of ventilation in
the human lungs
Sub-topics
1. Structure &
function of the
ventilatory
system
2. Structure &
function of the
cardiovascular
system
http://www.lib.mcg.edu/edu/eshuphysio/program/section4/4ch1/4ch1img/page17.jpg
IB
Sports,
exercise and
health science
Exercise physiology
2.1.5 Describe the significance of carbon
dioxide in the control of pulmonary ventilation
Topic 2
Exercise
Physiology
Sub-topics
1. Structure &
function of the
ventilatory
system
2. Structure &
function of the
cardiovascular
system

The entire respiratory system would be useless unless
the alveolar air were regularly changed. Since humans
do not possess a one-way system for air circulation
through the lungs, inhaled an exhaled air must be
mixed to some degree. This does not normally produce
any difficulty, since the respiratory system possesses a
two to threefold margin of safety and is ordinarily far
more effective than it needs to be in regard to oxygen
absorption.

Solomon & Davis
IB
Sports,
exercise and
health science
Exercise physiology
Topic 2
Exercise
Physiology
2.1.5 Describe the significance of carbon
dioxide in the control of pulmonary ventilation
Sub-topics

1. Structure &
function of the
ventilatory
system
2. Structure &
function of the
cardiovascular
system

This is less true, however for carbon dioxide removal,
which is an equally important task of the respiratory
system. Fortunately, carbon dioxide diffuses through the
alveolar walls far more readily than oxygen, but dissolved
carbonic acid does not readily breakdown to form carbon
dioxide. Were it not for the enzyme carbonic anhydrase,
which speeds the dissociation of carbonic acid as well as
it’s formation, the elimination of this gas would be
hopelessly inadequate.
As it is, carbon dioxide excretion is far more easily
hindered than is oxygen absorption. Thus breathing is
governed not by oxygen, but the carbon dioxide content
of the blood.

Solomon & Davis
IB
Sports,
exercise and
health science
Exercise physiology
2.1.5 Describe the significance of carbon
dioxide in the control of pulmonary ventilation
Topic 2
Exercise
Physiology
Sub-topics
1. Structure &
function of the
ventilatory
system
2. Structure &
function of the
cardiovascular
system

Whilst respiration appears at first a voluntary activity, if
that were true it would not continue when were asleep
or inattentive. It is subject to great conscious influence,
but despite the fact it is carried out by such voluntary
muscles as the intercostals and the diaphragm,
breathing is basically an automatic and involuntary
activity.

Solomon & Davis
IB
Sports,
exercise and
health science
Topic 2
Exercise
Physiology
Exercise physiology
2.1.6 Outline the role of hemoglobin in
oxygen transportation
Sub-topics
1. Structure &
function of the
ventilatory
system
2. Structure &
function of the
cardiovascular
system
http://www.nlm.nih.gov/medlineplus/ency/images/ency/fullsize/19510.jpg
IB
Sports,
exercise and
health science
Topic 2
Exercise
Physiology
Sub-topics
1. Structure &
function of the
ventilatory
system
2. Structure &
function of the
cardiovascular
system
Exercise physiology
2.1.6 Outline the role of hemoglobin in
oxygen transportation
Hemoglobin is the iron containing oxygen transport
protein in the red blood cells. It transports oxygen from
the lungs to the rest of the body, such as the muscles,
where it releases it’s load of oxygen.
The name hemoglobin is the concatenation of heme
and globin, reflecting the fact that each subunit of
hemoglobin is a globular protein with an embedded
heme (or haem) group; each heme group contains an
iron atom, and this is responsible for the binding of
oxygen. In humans, each heme group is able to bind
one oxygen molecule with one hemoglobin molecule
can therefore bind four oxygen molecules.
http://en.wikipedia.org/wiki/Hemoglobin
IB
Sports,
exercise and
health science
Exercise physiology
2.1.7 Explain the process of gaseous
exchange at the alveoli
Topic 2
Exercise
Physiology
Sub-topics

1. Structure &
function of the
ventilatory
system
2. Structure &
function of the
cardiovascular
system

Gas exchanges between the air in the alveoli and the
blood capillaries occur across the respiratory
membrane in a process known as pulmonary
diffusion. The most critical factor for gas exchange
between alveoli and the blood is the pressure gradient
between the gases in the two areas.
According to Dalton’s law of partial pressures, the
pressure of a mixture of gases equals the sum of the
individual pressures (partial pressures) of each gas in
the mixture.
Browne et.al
IB
Sports,
exercise and
health science
Exercise physiology
2.1.7 Explain the process of gaseous
exchange at the alveoli
Topic 2
Exercise
Physiology
Sub-topics

1. Structure &
function of the
ventilatory
system
2. Structure &
function of the
cardiovascular
system

If we take a normal breath of air, which contains
nitrogen, oxygen and carbon dioxide, the total
pressure of the air is equal to the sum of the partial
pressures of the individual gases in the blood and the
alveoli create a pressure gradient, so one into the
other (from high partial pressure to low partial
pressure)
The partial pressure of oxygen arriving at the alveoli is
high, and the partial pressure of it in the capillaries is
low. Therefore oxygen diffuses from the alveoli into
the blood. The opposite is true for carbon dioxide.
Browne et.al
IB
Sports,
exercise and
health science
Topic 2
Exercise
Physiology
Sub-topics
1. Structure &
function of the
ventilatory
system
2. Structure &
function of the
cardiovascular
system
Exercise physiology
2.1.7 Explain the process of gaseous
exchange at the alveoli
Be prepared for discussions
• Affect of exercise on hemoglobin at altitude
• What are some of the effects/results of
breathing air at altitude? Below sea level?
• What is the theory behind hyperventilation
for improved breath holding ability?