Every
cell, tissue and organ in our bodies serves a purpose. To understand how our
bodies work, we need to go deep into the body, to see and get to know the
mechanisms on how to most effectively lose weight.
Optimal
fitness performance is something we hear more and more each and every day. The
techniques vary greatly, not to mention the diet and rest to exercise ratio
(time spend resting versus time spent working out).
Optimal
fitness can be divided into three components: cardiovascular endurance,
muscular strength and flexibility. If you want to achieve optimal fitness, you
need to develop all three of the components equally. Today I will focus on the
cardiovascular endurance.
Cardiovascular
fitness had many different names, which mean pretty much the same thing. Among
them are cardiorespiratory endurance or, more commonly known, aerobic fitness.
It describes the ability of cardiac (heart), respiratory (lungs) and vascular
(blood vessels) system to deliver an adequate supply of oxygen to muscles. No
matter what name you use, you can always be sure, that all three of these
systems are included.
Let us
begin at the base of your lives – the heart. The heart is a muscle that starts
working when we are still in the womb and it continues to work until the day we
die. The hearts main job is to keep a constant blood flow through arteries,
veins and smaller capillaries.
It is
divided into four main parts: Left atrium, left ventricle, right atrium and
right ventricle. The left and the right sides are separated by the septum, and
the atrium and ventricles by valves. The left side pumps oxygenated blood
(blood that is filled with oxygen) and the right side transports deoxygenated
blood (blood filled with carbon dioxide).
Not to
bore you with physiological details too much, I’ll just skip over to the
important part.
The
heart creates a so called Cardiac output (Q). that is the amount of blood that
flows from each ventricle in one minute. If you want to know how much blood
pumps through your veins per minute you need to know the stroke volume (SV),
which is the amount of blood each ventricle pumps in one heartbeat. Now, If you
multiply SV with how many beats per minute (BPM) the heart makes, you get your
cardiac output.
Example
1:
When you
are resting your heart beats with a speed of around 60 BPM. The stroke volume
of your heart is 70 ml. Now, if we put the data in the equasion
Q = BPM
* SV
where
BPM is 60 and SV is 70 we get:
Q = 60
BPM * 70 ml
Q= 4200
mL
Q = 4,20
L
While
resting, our heart pumps a bit more than 4 liters of blood every minute!
I'll tell you more on the function of the human heart next week.
I'll tell you more on the function of the human heart next week.
Until
next time, keep strong and be kind.
Picture taken from: http://en.wikipedia.org/wiki/File:Diagram_of_the_human_heart_(cropped).svg
.svg){kind=link}
Heart is really an amazing part of our body! Do you have any data on normal values of BPM and blood pressure during several conditions - sleeping, sitting, running, cardio, etc.?
ReplyDeleteCan you explain in a simple way, how BPM of a heart is controlled by brains, hormones or other functions?
Ok in simple terms, the heart is a self controled muscle. The cells in the sinoatral nodule (SA) in the right ventricle depolarize and the depolarizing wave spreads through every cell in the heart, stimulating each of them to contract. If there is a problem with that nodule, the atrio ventricular (AV) nodule takes over, but the rythm it produces is much slower (around 30 - 50 BPM).
DeleteThe brain isn't as important in the regulation of the heart as the periferal nervous system is (stimulation of the vagus nerve, which is a part of the symphathetic nervous system, decreases the heart rate).
As for hormones, the most important one is adrenalin, which is produced in the adrenal glands increases the heart rate. Acetylcholine on the other hand, slows the heart rate down.
And lastly for other functions, the most important one is blood pressure. If the blood pressure is too high, the heart rate slows down (to reduce the cardiac output). The oposite happens if the blood pressure is too low. This is known as the "nervous reflex of the heart".
I hope this has helped you.