Transcript INTRODUCTION TO SPORT SCIENCE

INTRODUCTION TO SPORT
SCIENCE
SESSION 3:
BLOOD
PRESSURE
Contents
1) Theory (20min)
2) Practical (20 min)
Learning Objectives
• Understand how and why blood is
pumped around the body
Blood
• Blood is the liquid medium that flows throughout
our bodies
• Blood has many extremely import functions and
it is therefore vital that it gets transported around
the body
Functions of Blood
• Transport of O2 and CO2
• Tissue repair
• Blood Clotting
• Heat transfer
• Immune functions
• Acid-base buffering
• Transport of hormones
• Transport of nutrients
The Heart
• The heart pumps blood
around the body
• It’s the only muscle that
never stops working
during our lifetime
• The pressure the heart
creates is crucial for the
function of the heart and
the rest of the body
Superior vena cava
Arch of aorta
Pulmonary trunk
L pulmonary veins
Left atrium
Right atrium
Right ventricle
Inferior vena cava
Left ventricle
Apex
BLOOD PRESSURE
The pressure within the cardiovascular
system generated by the pumping of
blood by the heart
Systole and Diastole
There are two phases to blood pressure
Systole:
Phase during which the left ventricle of the
heart is contracting and is pumping blood
into the aorta and then around the body
Diastole:
The left ventricle is relaxing. As it relaxs it is
being filled with blood coming back from the
lungs
Systolic BP
Systolic pressure: the maximum pressure exerted in
the arteries when blood is ejected
into them during contraction
(systole)
Provides an estimate of the work of the heart and of
the strain on the blood vessel walls when the heart is
contracting.
It is around 120 mmHg in healthy individuals
It is the first number given in a blood pressure check,
e.g. 120/80
Diastolic BP
Diastolic pressure: the pressure within the blood
vessels when heart is relaxing.
The heart muscle receives it blood supply during
diastole
It is around 80 mmHg in healthy individuals
It is the second number given in a blood pressure
check, e.g. 120/80
Blood Pressure in Different Body
Positions
AIM: Difference in blood pressure between lying down, sitting and
walking
METHODS:
Equipment
Automatic blood pressure monitor
Protocol
Take the blood pressure of a partner with him/her lying
down,sitting up and following 5 minutes of brisk walking
RESULTS
Is there any difference in blood pressure?
DISCUSSION
Try to explain these differences.
Teacher Resource
 Force of gravity is the single most important factor explaining
the difference in blood pressure between lying down and
seating.
 When lying down (supine), the heart is at the same level as
the rest of the body. Therefore the work load is less here since
it doesn’t have to overcome the gravity.
 During exercise the heart contracts with more force and
pumps a greater volume of blood into the aorta. This will result
in an increase systolic blood pressure
 Diastolic blood pressure does not changes very much