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Title: TWIN FOR GOOD, TWIN FOR BAD:
THE HEART AND THE LUNGS WORK
TOGETHER
Date:Thursay, February 4,2010
Time:4.00 pm Prompt
Professor V.I Iyawe
107th Inaugural Lecture series
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DEDICATION
This lecture is dedicated:- To the Trinity, God the Father , Jesus Christ my redeemer and
saviour and the Holy Ghost, my instructor and guide.
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To my late parents, Mr William Igbinomwanhia Iyawe and Princess Victoria
Evbayowieru Iyawe (nee Okundia Ezomo) who exerted strict discipline on
me and made extreme sacrifice to educate me.
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To my wife Helen Okhuosuri Iyawe (nee Bazuaye) who has been my best friend,
great supporter and encourager, and chief confidant.
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To my lovely children who are all young pastors: Dr Osahon, Dr Ikponmwosa, Mr
Osama, Engr Idahosa and Miss Osemwonyenmwen. You have made me proud and
given me great joy and peace.
TWIN FOR GOOD, TWIN FOR BAD: THE HEART AND THE LUNGS WORK TOGETHER.
INTRODUCTION:
God created man in the likeness of His image to be the master of all He had created (Gen
1:26-27). He took time to fashion and order every cell, every tissue and every organ in the
body. There are 100 trillion cells, 206 bones and 600 muscles, and 22 internal organs
in the human body. The cells, tissues and organs are organized into many systems.
The systems of the human body are:
1. Blood and Body Fluid System (blood cells, plasma, water)
2. Cardiovascular System (heart, vessels)
(1+2 = Circulatory System).
3. Respiratory System (nose, trachea, bronchi, lungs)
4. Immune System (many types of proteins, cells, organs, tissues)
5. Skeletal System (bones, cartilages)
6. Excretory System (lungs, large intestine, kidneys, skin)
7. Urinary System (bladder, kidney, urethra)
8. Muscular System (muscles)
9. Endocrine System (glands, cells)
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10. Alimentary / Digestive System (mouth, esophagus, stomach, intestines, liver)
11. Reproductive System (male and female reproductive organs)
12. Nervous System (brain, spinal cord, nerves)
The organs and systems of the body are neatly fitted and well coordinated, thus making
the whole body function as one unit. Hence we can say we are fearfully and wonderfully
made and packaged by God. (Psalm 139:14). The body is designed for excellent fit. God
put in our body many vital organs. Of the organs, the brain, heart, lungs and kidneys are
most notable. Of these organs, the heart is twinned with the lungs. They function
and work together. It will become obvious at the end of this lecture that in health and
during various interventions, the heart and the lungs act together. In disease, they also
suffer together.
Today, I will focus largely on these two organs, the heart and lungs, which God encased
closely in a compartment called the CHEST, thus setting up a special relationship between
them.
Fig 1:
The Heart and the Lungs Encased in the Chest
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The lungs and the heart are related and serve the same purpose, essentially to cooperate
and deliver nutrients to the body. Both interrelate to deal with gas and blood. The heart
pumps blood to the lung. The lung filters waste (CO2) away from the blood,
sends the gas into the atmosphere, adds the life-giving nutriment (O2) to the blood and
sends it back to the heart for onward delivery to the other organs and tissues of the
body(circulation). In a healthy person, the volume of blood pumped by the heart to the
lungs is the same volume delivered by the lungs to the heart. This is approximately equal to
5 litres every minute.
The heart and the lungs are vital to life and this is evident both at the beginning and end of
life. They kick start life for the baby (New born) to cry and when they cease to function it will
be obvious even to the non-expert that life has come to an end (Death). There will be no
chest movement signifying that breathing has stopped. At the same time there will be no
pulse, HR or BP signifying that the heart has stopped. No wonder the Bible says, “ a sound
heart is the life of the flesh” Prov. 14:30
Because of their proximate anatomical locations and functional relationships, whatever
adversely affects the lungs may have deliterious consequences on the heart. Similarly,
many of the problems of the lungs are the sequelae of a sick heart. . It is difficult to change
heart function and blood circulation without affecting the breathing process and vice versa.
In exercise, as we shall see later, both the cardiovascular and respiratory systems adjust
positively and simultaneously (Whipp et al 1982, Iyawe et al 1983, and Cummin, Iyawe et
al 1986)
It is also divinely arranged that the two organs are controlled and regulated from centres in
the same part of the brain called medulla oblongata which is a distinct portion of the brain
stem. (Boxers are not allowed to hit this part of the body because of the adverse effect it
will have on the functions of the heart and lungs). The centres and neurons in the medulla
which control the functions of the heart and lungs are closely located and inter-related. The
input and output tracts are essentially the same… the ix and x cranial nerves i.e.
Glossopharyngeal and Vagus respectively.
Little wonder that the heart and lungs work together as we shall see in the course of this
lecture. When all is well with the body, both organs are well. When one organ is sick, the
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other will most certainly be affected sooner or later. Invariably, one drags the other along in
health and in disease conditions.
“TWINNESS” OF THE HEART AND LUNGS
How can we say there is twinning when we have 3 organs – one heart and two lungs. Now,
this is why we can talk of twinning, that is, the heart is twinned with the lung(s). The two
lungs are one. In certain pathological conditions, segments, lobes or even a whole lung can
be removed from a human being e.g. in bronchial carcinoma and severe lung abscess. In
these conditions, removal of the affected lobe (lobectomy) is the accepted procedure or
treatment of choice.
Apical
Upper Lobe
Apical
Upper Lobe
Anterior
Upper Lobe
Apical
Middle Lobe
Lateral
Middle Lobe
Inferior
Lingular
Anterior
Lower Lobe
Posterior
Lower Lobe
Lateral
Lower Lobe
Fig 2:
Posterior view of Broncho Pulmonary Segments of the Lungs
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Apical
Upper Lobe
Posterior
Upper Lobe
Anterior
Upper Lobe
Apical
Middle Lobe
Medial
Lower Lobe
Medial
Middle Lobe
Anterior
Middle Lobe
Posterior
Lower Lobe
Anterior
Lower Lobe
Lateral
Lower Lobe
Fig 3:
Anterior View of Broncho – Pulmonary segments of the Right lung
The alternative treatment in bronchiogenic Ca is major/extensive pulmonary resection (total
or radical pneumonectomy) i.e. the whole lung on one side is removed. In the elderly,
however, those above 65 years of age, this total pneumonectomy increases the risk of
morbidity and mortality because of the greater ventilatory handicap imposed on the patient.
If the patient is much younger, there is usually, little hesitancy about removing the entire
lung; especially if the lung function studies are satisfactory.
A young man of 48 years who was suffering from epidermoid Ca of the bronchus, but had
excellent lung function before surgery still lived a vigorous lifestyle after the removal of his
lung (resection or pneumonectomy). He was able to play gulf 3x a week, 3 years post-op,
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without signs of loss of function. That a man can cope with one lung is evidence that one
healthy lung can provide near perfect function. Hence we can say the two lungs are one
and that the lungs and heart are twins. The lungs are two in one, function as one, and
are twinned with the heart which has two sides in one organ.
Some of the experiments in this lecture will further lend credence to this assertion .So far,
the basis for the “twinnesss” of the heart and lungs can be summarized thus:
* Encased in one compartment- the chest.
* Controlled and regulated from the medulla.
* Input and output tracts/nerves are the same.
* Both are volume pumps, one for blood, one for air.
* What affects one invariably affects the other.
(On another note, just as there is a right and left lung, the heart has a right and a left side)
My researches have largely concentrated on the relationship between the two organs or
systems. A few of the researches deal with the cardiovascular system only, but most of my
recent works have focused on the lungs. I have done several other works on smooth
muscle, blood, breast milk, hearing, the eyes etc. in collaboration with colleagues in this
University and outside. Time will not permit me to go into those other areas. I worked with
collaborators like Professors Ebeigbe, Aloamaka, Ighoroje and Orie who are renowned
physiologists, Prof. Ogisi of ENT, Drs Ajayi and Akinlabi of the Department of Optometry,
Ehigiegba of the Dept of Obstetrics and Gynaecology, and Egbagbe of the Department of
Medicine. Also on this list is Dr (Mrs.) M. Oseji of the Ministry of Health, Asaba. One of my
works with Dr. Akinlabi who is my PhD student was on the effect of mushroom extract on
Ocular hypertension. The article from this work won the award for the best article in 2008
College of Medical Sciences Journal. In this group is Prof. Steve Ufearo, Dean of Basic
Medical Sciences, Nnamdi Azikiwe University. He was our PhD student, co-supervised
with Ighoroje and did some work on breast milk which this lecture will not address. There
are several other research works, which will not be mentioned. For example, I wrote a book
together with Professors Ojeme and Oshodin (our respected VC) on several aspects of
Physical Exercise, and Health Education which cannot all be accommodated within the
scope of this lecture.
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Doppler Ultrasound Measurement of Cardiac Output (C.O)
We were among the first group of researchers to use the Doppler ultrasound method to
determine rapid changes in blood flow in the human body. We showed that with the
ultrasound technique it is possible to measure C.O. non – invasively in humans at rest and
even more novel, during exercise. (The beauty of this method is that nothing is injected into
the patient or subject and nothing is inhaled by the patient or subject). Cardiac output was
derived heart-beat to heart-beat by measuring blood flow in the ascending aorta using a
velocity meter, and aortic diameter with M-mode echocardiography.
Fig 4: Location of transducers and direction of ultrasonic beams for Doppler and M-mode
echo measurements – the Doppler transducer at the supra-sternal notch and the echo
transducer at the 4th intercostals space.
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We measured C.O. with this technique in normal people who exercised (high cardiac
output) and in patients with heart failure (low cardiac output) being treated in Intensive Care
Unit (ICU). The technique was used simultaneously with other conventional, but invasive
techniques like thermodilution and rebreathing methods. Over a wide range of C.O. (0.5 –
10L/min) we obtained excellent overall correlation between C.O. from our new technique
and the older invasive techniques. (Mehta, Iyawe et al 1985).
Fig 5: Concordance Plot of C.O. Values Determined by a New and an Old Method.
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Fig 6: Comparison of C.O. Values from Doppler Compared with Thermodilution and N2O.
The high correlation or agreement in C.O. measurements gave us the confidence to use this
Doppler method. The Doppler ultrasound technique offers an excellent temporal resolution
in blood flow throughout the cardiac cycle and it is therefore invaluable in documenting
transient and rapid changes in various cardiovascular flow parameters. It is useful in both
on – and off – transient situations i.e. condition in which C.O. is changing rapidly. Its 2 key
advantages are:
(1)
(2)
It is non-invasive and non-injurious, and
It is possible to measure C.O. frequently and obtain a wide range of
C.O. values (50-70 values) in one minute, at rest.
Ordinarily, we hear of few areas in which the ultrasound technique has gained popularity in
use. In Cardiology, it is useful in assessing the heart and its chamber sizes, septal defects
and vavular functions or dysfunction. In Obstetrics and Neonatology, it is useful in the
diagnosis of multiple pregnancies, tubal pregnancy, evaluation of fetal size (growth and
retardation) and movement, identification of sex, organ aberrations and developmental
abnormalities in the fetus. It is also used in the diagnosis of tumours i.e. abnormal
growths in various organs of the body e.g. fibroid in the uterus.
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Aside from these well known uses, the Doppler ultrasound technique has been found to be
useful in many other physiological and clinical conditions (Iyawe 1999). We were
particularly interested in its use for the measurement of blood flow and blood volume. In
this regard, the ultrasound method is now used in the following areas:
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√ Measurement of C.O. in health and diseases.
√ Changes in Cerebral Blood Flow (CBF) during exercise, postural
maneouvres and drug application.
Assessment of CBF during cognitive tasks.
Monitoring of neurosurgical emergencies e.g. head injury, subarachoid
haemorrhage and changes in intracranial pressures.
Tracking and detecting cerebral emboli.
Evaluating blood vessel activities during migraine.
Assessment of fetal heart rate and measurement of maternal and fetal
blood flow.
Pre - and post – operative assessment of blood vessels.
Measurement of penile blood flow etc.
We were the first to use the Doppler technique to measure cardiac output during
exercise (Mehta, Iyawe et al, 1985).
RELATION BETWEEN CARDIAC OUTPUT AND VENTILATION
First, it is necessary to define the two most important parameters which were measured in
many of the experiments to be described, namely Ventilation and Cardiac Output.
1. Ventilation (V) is the volume of air that can be taken into or given out of the lungs
over a period of one minute. In the humans, the average ventilation rate is 6
liters/minute. V is a good indicator of lung function.
2. Cardiac Output (C.O.) is the volume of blood pumped out by the left or right ventricle
in one minute. In the humans, the average cardiac output is 5 liters/minute. C.O. is
an index of the functional state of the heart.
In several of my experiments, both indices i.e. V and C.O. were measured pari-pasu to
ascertain the relationship between the heart and the lungs. The experiments provided
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convincing evidence for a positive interaction between C.O. and V (Iyawe 1989). A
change in one function affected the other, a relationship predicated on the proximate
locations of the two organs.
Physical Exercise (Cycle Ergometer)
Dynamic exercise was used. In dynamic exercise e.g. running and cycling, the muscles
used are contracting and relaxing alternately throughout the exercise. In the first few
seconds of this exercise, there is an abrupt increase in V. During the first 20 seconds of this
exercise, C.O. and Venous return upon which C.O. depends also increase. We then asked
ourselves if there was any relationship between the increase in V and the increase in C.O.
at the onset of exercise i.e. is there a cardiodynamic increase in V? To test this hypothesis
we needed to do simultaneous measurements of V (breath by breath) and C.O. (beat by
beat).
Fig 7: Experimental Set Up
We had used the Fleisch Pneumotachograph (integrated) to measure V, breath to breath,
and as mentioned earlier, we developed a continuous wave Doppler ultrasound technique to
measure beat to beat flow in the ascending aorta (Mehta,Iyawe et al 1985).
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Fig 8: Integrated Airflow (top) and Blood Flow (bottom)
What did we find? During rest to exercise transition, the pattern and volume of the
increases in C.O. were similar to the increases in V in the first 20 seconds of exercise
(Iyawe et al 1983 and Cummin, et al 1985).
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Fig 9: Time Course of the Changes in V and C.O.(Q)
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Fig 10: Regression of V on C.O.
These findings suggested that there was a matching of the changes in V with the changes
in C.O. in early exercise. The findings were compatible with the cardiodynamic drive of V,
even though the link did not appear to be simple. Based on our findings, we accepted the
central command theory or a central feed – forward drive for both V and C.O. as proposed
by Eldridge et al 1981. In addition, we put forward a positive feed-back as a further
regulating mechanism during the controlled amplification of both V and C.O. which must
occur in exercise. The combination of a feed-forward drive with both negative and positive
feed-back loops as an explanation for the simultaneous increase in both V and C.O. was
novel. With rapid measuring tools, we were the first to scientifically explain the increases in
both V. and C.O. at the start of dynamic exercise and to establish the positive relationship
between them (Cummin, Iyawe et al 1986). Thus, I can say categorically that the effects of
exercise on the respiratory and circulatory systems occur together in an integrated
fashion during the early phase of exercise.
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Voluntary Hyperventilation
Subjects hyperventilated voluntarily (force-breathed or increased their breathing on their
own volition for 45 seconds (Iyawe et al 1985 and Cummin et al 1986). Because V=BR x VT
(i.e. breathing rate x tidial volume), to increase V, you either increase BR or increase VT or
increase both.
The following protocols were used:
i
increase in BR with VT kept constant,
ii
increase in VT with BR kept constant.
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increase in both BR and VT. In all protocols, end-tidal PCO2 was not controlled, and
this fell by 4 to 8mmHg. C.O. increased in all 3 protocols, as V increased.
Another protocol was performed in which the subjects increased both VT and BR, but with
PCO2 maintained at a constant level (38+-2mmHg). In these experiments, C.O. increased to
the same proportion as it did when PCO2 was not controlled.
Our earlier proposition from dynamic exercise study was that the increase in V was
cardiodynamic i.e. increasing C.O. had possible positive effect on V. The experiment on
hyperventilation showed that increases in V by this method also caused increases in C.O.
The experiment provided further evidence for our hypothesis involving a stable positive
feedback relation between V and C.O. In otherwords, when V increases, C.O. increases,
and invariably, when C.O. increases, V also increases. An increase in one causes the
other to increase.
Posture and Changes in V and C.O.
To see what happened to ventilation when cardiac output changes, we changed venous
return transiently by postural manoeuvres and by creating lower body positive pressure.
This work was published in J. Physiol (London; 1986). The Medical Anti-shock Trouser
(MAST) was used to create positive pressure in the lower abdomen and limbs in order to
increase C.O. This technique has assumed prominence recently in the management of
difficult labour in addition to its regular use in increasing C.O. and treating circulatory shock.
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Fig 11: Medical – Antishock Trousers (MAST)
Fig 12: Medical – Antishock Trousers (MAST)
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MAST was used to deliver positive pressure (at 40 and 80 mmHg inflation) and V was
measured breath-to-breath and C.O. measured beat-to-beat by a Doppler ultrasound
technique. The procedure was done with subjects lying either head-up or head-down tilted.
In a similar experiment, we measured transient/immediate changes in V and C.O. on raising
and lowering the legs.
Both experiments which involved increase in C.O. which is dependent on an increase in
venous return, showed that there is a link between V and C.O, when C.O. changes rapidly.
We were unable to dissociate entirely increasing V from increasing C.O. since the changes
in both were approximately in phase. Once again, we showed that V and C.O. are related
and interdependent. (Iyawe, 1987)
A SHIFT FROM DYNAMIC TO ISOMETRIC EXERCISE
In the earlier experiments, we used dynamic/aerobic exercise in which there is frequent
contraction and relaxation. In the experiments I am about to describe, we used
isometric/static exercise, in which the exercising muscle stays contracted for a while without
relaxation, to test the relationship between C.O.and V.
At this point, it is pertinent to make clearer the difference between Dynamic (Isotonic)
exercise and Static (Isometric) exercise. Dynamic exercise primarily involves the
contraction and relaxation of muscles (movement of joints in involved) – walking, running,
swimming and cycling are good examples. In isometric contraction the muscles are static
(no movement of joints). Weight lifting and load carrying are good examples of isometric
exercise.
During dynamic exercise of brief duration, and below anaerobic threshold, that is not
severe, the increase in C.O. is matched by the increase in V, such that there is little change
in CO2 levels in the arteries (CO2 levels affect both V and blood flow in the body). The
question to answer was this. Does the matching in the increase in V and C.O. take place
during isometric exercise? In other words, are the increases in V and C.O. proportional ?
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To answer this question, the effect of hand grip isometric exercise on V, PCO2, BP, H.R and
cerebral blood flow was studied (Lawton, Iyawe et al 1996, Imms, Iyawe et al 1998, Iyawe
2000). Cerebral blood flow velocity was measured in the middle cerebral artery, as usual,
with the Doppler ultrasound method. The isometric exercise was performed combined with
LBNP of – 20 mmHg and -40 mmHg. In most subjects, cerebral artery velocity, BP, HR and
V increased (with PCO2 not changing significantly) but the increase in blood flow was not
proportional to the increase in V, and the increases were not affected by LBNP. Indeed,
some subjects hyperventilated i.e. increased ventilation out of proportion to the work done.
However, in subjects who hyperventilated and dropped their PCO2 significantly, mean
cerebral blood flow velocity also decreased significantly below control levels; and more so
when exercise was combined with LBNP (CO2 levels are useful in the control of vessel size
and blood flow). Hyper V or over-breathing, occurred more frequently in the elderly (people
above 65 years), in whom postural hypotension and orthostatic intolerance are common.
Because C02 levels fall easily in the elderly, their brain vessels dilate.
The decrease in brain blood flow (i.e. cerebral hypoperfusion) is dangerous because
it can lead to dizziness, fainting and even a fall. Hence the elderly men/women who
are 65/70 years and above are generally advised not to perform isometric exercise
e.g. carrying a heavy load like a block, a bag of cement, or carrying a bucket full of water
even for a short distance. Of course, there are other possible deleterious effects on the
waist and spine in the elderly e.g. slipped disc is a common problem together with
unexplained back and waist pain.
CAFFEINE STUDY
Iyawe et al 1990 found that a cup of coffee, containing 250mg of caffeine has a stimulant
effect on the Respiration and the Heart. Caffeine causes broncho-dilation, thus
enhancing airflow in the lungs, stronger and increased heart contraction, and better
blood flow. These effects occur maximally, 39 to 45 minutes after oral ingestion of the
caffeine. In otherwords, the beneficial effects of caffeine are noticed within an hour of the
consumption of coffee. Interestingly, doubling the dosage of caffeine or increasing the
number of cups does not bring about proportional increase in bronchodilation and airflow.
In fact, we found no significant difference between the response to 250mg and 500mg of
caffeine in non-regular caffeine users. In those who are habituated or addicted to caffeine,
a much higher dosage is required if respiratory or cardiovascular stimulation is to be
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observed. But a word of caution! Chronic usage of caffeine and a heavy dosage of it can
cause bronchoconstriction and vasoconstriction. Such high dosage is therefore not good for
the elderly, and patients with Asthma, Hypertension, Arrhythmias and other cardiovascular
diseases.
Idiosyncrative effects of caffeine are well known. That is, whereas it gives physical and
mental strength and improves lung and cardiovascular function in some individuals, a few
grains of coffee may cause sleeplessness for days in other individuals. Overall, the benefits
of a mild dose of caffeine (one cup) once in a while are more than the unlikely damage.
Recently it has been found that caffeine reverses memory impairment in mice. Prof. Gary
Arendash (2009) and team of the University of South Florida (USA) showed that caffeine
decreased abnormal levels of the protein linked to Alzheimer’s disease both in the brain and
in the blood of mice exhibiting symptoms of the disease. Thus, it is plausible to suggest that
mild to moderate consumption of caffeine (not more than 500mg, that is one or 2cups) daily
may benefit those destined to develop Alzheimer’s disease (memory loss). Drinking coffee
could also cut the risk of prostate cancer and lower the risk of developing adult onset
diabetes.
The frequent use of caffeine and a high concentration of it is the real problem! Caffeine
intoxication is marked by nervousness, anxiety, insomnia (sleeplessness), tremors, g.i.t
upset, tachycardia (rapid heartbeats), psychomotor agitation (restlessness and pacing),
arrhythmias (irregular heartbeats) and in extreme cases, death.
GARCINIA CONRAUANA (Bitter Kola)
The work of Dr Ebomoyi on bitter kola during her doctoral thesis gave similar results to that
of caffeine (Ebomoyi and Iyawe, 2000 and 2003). Mild doses of this kola decrease airway
resistance and improve airflow in the lung. We also found that mild doses of bitter kola
improved lung function in Asthmatics (Ebomoyi et al 2004). This publication won the award
of the best article in the College of Medical Sciences in 2004. Like coffee, excessive
consumption of bitter kola is harmful.
STUDY ON CIGARETTE SMOKE
Cigarette has been known to be dangerous to the health of humans. Cigarette smoking can
aptly be described as an act of preparation for suicide. Virtually all the organs and
systems of the body are affected by the more than 4,000 chemicals in cigarette
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(Winstanley et al, 1995). More specifically, nicotine (and its metabolite cotinine) and carbon
monoxide are frontline tissue and cell destroyers. The cardiovascular and respiratory
systems which are directly in the pathway of the chemicals are most adversely affected.
Common adverse conditions are Coronary Heart Disease and Hypertension for the
cardiovascular system and Chronic Obstructive Airway Disease and Bronchial carcinoma
for the lungs.
Usually, it is the chronic use of any substance that does damage to the human body.
Immoderate use and consequent accumulation of the substance causes disease. This is
the mechanism by which nicotine and other substances in cigarette bring on ill-health. For
nicotine, not even a little use or moderation is advisable. It should be completely avoided.
Cigarette smoke is so dangerous that even exposure to Environmental Tobacco Smoke
(ETS) or secondary smoking in the course of time leads to reduced lung function, increased
risk of lower respiratory illnesses, increased risk of asthma and acute exacerbation of
asthma. In adults, there is increased risk of cancer and acute and chronic respiratory
symptoms which can improve after the cessation of exposure.
ETS promotes tumour growth and angiogenesis. Cigarette smoke also causes destruction
of cilia and decreased mucus clearance. The complications, including the so-called
“smoker’s cough”, are particularly noticeable when a person smokes over a long time. The
smoker is unable to remove mucus normally from the airways, because of the increased
volume of mucus and the destruction of cilia.
We therefore decided to see what happens in the airways when a single suck or puff of
cigarette smoke is taken (Iyawe et at 2007). Peak Expiratory Flow Rate (PEFR) was
measured following a single puff of cigarette smoke. Healthy young non-smokers took a
single puff also. The result was very revealing.
Following one suck, there was an increase in airway resistance which manifested in a
significant decrease in PEFR, especially in the non-smokers. A decrease in PEFR is
an indication of narrowing of airway, resulting in difficulty in breathing (Iyawe et al
2007). It was like a shock treatment to the airway! What is the message here? It is (1)
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Don’t smoke, (2) Don’t associate with anyone who smokes, and (3) Go far away from where
people are smoking.
In the study, both heart rate and blood pressure (indices of CVS) also reactively
increased, showing that both the respiratory and cardiovascular systems would be
adversely affected.
What does this study point to? If a single puff of smoke can cause significant airway
narrowing, repeated smoking over time will progressively narrow and damage the airways.
Furthermore, if tobacco contents (nicotin, cotinin etc.) in cigarette, pipe or snuff adversely
affect healthy humans, it must be harmful and awful for asthmatics and hypertensives to
smoke, directly or secondarily. Of course, it endangers the life of the baby in the uterus in
the pregnant woman who smokes, or inhales the smoke from other people.
In addition to reducing lung function, we have also, like other workers, found that
smoking made respiratory symptoms (chest pain, mucus production, cough etc.) much
worse-Ugheoke et al 2006. Fortunately, smoking is no longer a serious problem, as it has
become culturally unfashionable and unacceptable.
INDUSTRIAL HEALTH (Industrial hazards and lung function)
We found a decrease in lung function (PEFR, FEV1, and FVC) in cement factory workers
(Alakija, Iyawe et al, 1990). The nature of the job done in the cement factory and the
duration of service were important in the progressive loss of function. Workers at the quarry
site, mill feeders and loaders who were in direct contact with coarse and fine cement dust
particles suffered more than the administrators, plant technicians, laboratory staff, security
men and other support staff. Those who had worked for more than 10 years in the factory
had a significantly lower lung function than newly employed staff, inspite of the fact that both
groups were mostly of the same age (between 30 and 40 years). Definitely, inhalation of
cement dust over a long period impairs lung function. Also, there were more
hypertensives among those who were in direct contact with cement dust (Iyawe et al.
2000)
In another study on spray painters, we found that paint fumes significantly reduced PEFR
and thus have negative effects on respiratory function (Agoreyo and Iyawe, 2007). The
spray painters were, to some extent, aware of the likely effects of spray paint fumes. In
spite of taking precautionary measures like using nose mask, their PEFR were much lower
than those of non-spray painters, of the same age, height, weight and working in the same
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environment e.g. automobile mechanics and electricians. Thus, spray paint fumes
increase airway resistance (i.e. airway narrowing) and in the course of time will cause
difficulty in breathing. In this study, spray painters also had a higher blood pressure than
non-spray painters.
Workers in the sawmill industry who had direct contact with saw dust had reduced
PEFR, an indication that airway resistance increased and airflow decreased (Ughoeke,
Ebomoyi, Iyawe 2006). In addition to the reduced lung function the sawmill workers who
smoked were worse, as they had a myriad of respiratory symptoms like chest pain,
excessive sputum production and cough. A combination of the inhalation of dusts, for
example cement or saw dust, and cigarette smoke is a recipe for disaster.
Repeated inhalation of smoke whether from cigarette (as reported above) or from other
sources, causes a reactive airway dysfunctional syndrome, but the carcinogenic effects
of cigarette are well documented. We found an increase in respiratory symptoms (cough,
sputum production, breathlessness and chest-pain) and reduction in PEFR in women who
cooked with fire wood compared to women of higher social class who cooked with gas
and electric cookers (Ibhazehiebo et al 2007a). The increase in respiratory symptoms and
the low PEFR in women following exposure to chronic domestic wood smoke, the severity
of which was related to exposure time, indicate that prolonged exposure to wood smoke
is capable of impairing lung function. Obviously, cleaner sources of fuel for domestic
cooking and the use of well-ventilated kitchens are recommended. The increases in BP
found in these women were related more to age and stress than the smoke.
One can conclude on this section on Industrial Health that it is unfortunate that there is very
minimal knowledge by industrial workers of the health hazards in Nigerian industries and
that the practise of occupational safety in these industries leaves much to be desired as we
found in a study of one Textile Mill (Oseji et al 2005)
EXERCISE AND CARDIO-RESPIRATORY HEALTH.
Man has evolved for a physically active mode of life and for regular bouts of sustained
submaximal exercise. He is by nature a standing, walking, running, jumping and climbing
creature. Indeed the early man and woman were created extremely active, that is, a
gardener, farmer, hunter or normadic shepherd. In the modern world, however, man walks
on belts, runs on wheels, jumps on lifts, climbs on escalators and lets the fingers do the
walking. While technology is taking the drudge out of his life, giving him more time to relax
(in his airconditioned bedroom, car and office), his body misses its natural exercise and thus
becomes unfit. Fitness is the capacity to perform heavy exercise with the least
disturbance of physiological mechanisms. In other words, fitness is the capacity to
24
enjoy moderate to severe endurance activity without a feeling of discomfort (Iyawe
1993). Many of us cannot climb straight to the 3rd floor of a high rise building without having
cardio-respiratory disturbances like palpitation, breathlessness, panting and weakness of
the legs, and even stopping on the way to have some rest. Some of us prefer the ground
floor of an office block to the 4th or 5th floor.
Muscular exercise imposes the most potent of all physiological stresses on the heart and
lungs and yet the systems controlled by these organs benefit maximally from exercise. The
effects of exercise on the cardiovascular and respiratory systems occur together in
an integrated fashion.
Regular and adequate exercise is of great benefit to the heart and lungs and is a natural
defense of the body against certain diseases. Even when diseases have occurred, exercise
can be a non-pharmacological way of treating some diseases, for example high BP, Chronic
Obstructive Airway Diseases, Stroke and muscle weakness from other causes. Generally,
exercise helps to maintain or increase body stamina, strength and flexibility.
In preparation for life’s adventures and vicissitudes, a heightened awareness of health and
training method that promote physical fitness is now widespread. A large number of
Nigerians are gradually engaging in some form of daily exercise. The high social class who
are financially endowed, visit commercial gymnasia. However, exercise or work and its
benefit can be obtained free, by gardening, walking round the house, running up and down
the staircase etc.
A word of caution! Every one, especially an adult, going into exercise needs medical
examination. This presents an excellent opportunity to assess any factors that might affect
performance or prevent participation in exercise altogether. Cardiac patients and those with
incipient, latent and potential heart problems should be advised on exercise routine, but not
totally restricted. Those with unexplained cardiac enlargement, systolic murmur and a
variety of ECG abnormalities should be carefully monitored (Iyawe, 2000)
Importantly, blood pressure levels must be monitored in those going into exercise or
competitive sports. It is not the custom of physicians to restrict participation in sport to
anyone with initial diastolic blood pressure in the range of 90 to 105 millimeters of mercury.
The type of sporting activity and the athlete’s response to it during a period of follow-up are
very important factors in making this decision. If athletic activity seems to be associated
with worsening of the blood pressure, curtailment of the activity in question is advisable.
Fortunately, many studies show that endurance training reduces both systolic and
diastolic blood pressures in persons with borderline, mild and moderate essential
hypertension, (Iyawe et al, 1996), not severe or malignant hypertension.
25
In our 1996 study on Nigerian hypertensives, who walked on treadmill and rode on cycle
ergometer regularly for 16weeks, systolic pressure decreased by 15mmHg in young
hypertensives and by 10 mmHg in older hypertensives; and diastolic pressure decreased by
8 mmHg in young hypertensives and by 4 mmHg in older hypertensives after 16 weeks of
regular exercise. Recently, we also found this reduction in BP in young obese nonathletic undergraduate students (Ibhazehiebo et al 2007b) with normal BP and borderline
hypertension.
On the respiratory side, gas exchange problems and increased airway resistance during
exercise are the conditions to worry about. Sports and physical activities in the lives of
asthmatics should play a role identical to that in normal subjects, and, if properly
approached can have very beneficial effects. Therefore asthmatics should not be
unnecessarily restricted,` (Wilson,1983). Asthmatics can exercise, depending on what
triggers off the asthma. Care should be taken, however, in those with exercise – induced
asthma. With suitable control, even those with exercise-induced asthma can compete with
distinction.
Environmental factors, altitude, temperature and humidity should be considered for those
going into exercise. Heat can be a major cause of morbidity and mortality among athletes
and those exercising or participating in competitive sports especially if the sports is outdoor.
Mild exercises like walking, gardening and cycling do not need special precautions under
normal environmental conditions.
Finally, to maintain physical conditioning, exercise must be continued on a regular
basis. Adults should engage in about 30 minutes of physical activity 3 or 4 days, and
preferably all days of the week. The 30 minutes can be divided into short bursts of 8 to
10 minutes, three times a day, as long as the activities are of moderate intensity. Two
weeks of detraining may be associated with some reduction in working capacity. Moreover,
if exercise is discontinued, cardio-respiratory fitness may decrease by 50 percent
within one to three months.
EXERCISE, THE HEART AND BLOOD VESSELS
Fletcher et al 1974 reviewed evidence for a good correlation between physical activity and
lowered risk of coronary heart disease. Epidemiological studies on London transport
workers showed that bus drivers had many more heart attacks than bus conductors who got
much more exercise going up and down the stairs of double decker buses, all day (Morris,
1953). In another study exercising monkeys fed with fat, developed larger hearts and
cleaner arteries, that is, no fatty plaques, while the sedentary monkeys fed with fat, showed
26
marked atheroma. The isolated working hearts of trained rats also demonstrated an
increased resistance to hypoxia, showing less O2 damage (Barnard, 1975)
In the circulatory system, exercises which are well planned, structured, repeated and
adequate lead to reduction of both systolic and diastolic blood pressure in the long term
(Iyawe et al 1996). The beneficial effect of exercise on blood pressure (BP) are well
documented. In Nigeria, Akinkugbe et al (1969) showed that urban dwellers have higher
levels of BP than their rural counterparts. Oviasu (1980) also indicated that the area of
residence and the type of occupation, especially occupation involving strenuous activities as
opposed to sedentary occupation are important factors affecting BP.
As a matter of fact, it has been shown that BP decreases in association with increased
cardiovascular fitness induced by moderate to intense exercise (Choquette et al 1973).
Our 1996 report also showed that with regular exercise, there is a rise in high density
lipoproteins (HDL) and a fall or no change in the low density lipoprotein (LDL). High levels
of HDL lower the risk of developing coronary heart disease and atherosclerosis while high
levels of LDL are directly linked to a high risk of heart disease. Put simply, exercise
prevents the build up of fatty plaques in blood vessels in the heart and elsewhere. During
exercise, BP actually goes up, opening up capillaries which have been inactive thereby
increasing the rate of blood flow and nutrient supply to the heart muscle, other muscles and
organs. Exercise training might stimulate the development of the side branches of coronary
arteries (that is collaterals) and so increases the flow of blood to the heart or bye pass any
obstruction (Schoop, 1964).
Exercise and physical training are used in the management of peripheral arterial
insufficiency, for example, intermittent claudication because of the increased blood flow,
together with increased activity of oxidative enzymes in the skeletal muscle (Scherten,
1983). Ultimately exercise has a relaxant effect on the smooth muscle of blood
vessels, decreasing the vessel resistance to blood flow and thus decreasing blood
pressure.
It is now well established that people who maintain their BP at the lower end of pressure
ranges (systolic of 120mmHg or less, and diastolic of 80mmHg or less) have better long
term cardiovascular health than people who do not ( Iyawe et al 1996). Other cardiovascular
indices are also affected. There is decreased HR, increased SV, increased red cell count
and Hb concentration, and reduced blood clotting tendency. For this purpose, mild to
moderate exercise is what is desired not necessarily strenuous exercise, or top athletic
performance. However, the exercise must be adequate, regular, constant and frequent,
and the tempo maintained.
27
EXERCISE AND THE LUNGS
Various indices of respiration improve with training. Transport of gases and their diffusion in
lung tissues are better, ventilation/perfusion ratio (V/Q) becomes more uniform resulting in
more efficient gas exchange in the lung (Bjurstedt et al 1968 and West, 1974).
Vital capacity (VC) has been discovered to be one of the better fitness indices in any
population (Thomas , 1972). Training during adolescence increases VC and total lung
capacity. Though the average VC of athletes is not much larger than normal (5 litres
against 4.5 litres for men), some first class sports men have extremely large lungs with VC
of 6 litres and more (Iyawe and Jarikre,1990). Paradoxically, exercise and physical
training are of great benefit in the rehabilitation of patients with respiratory
impairment including asthma and chronic obstructive airway disease (e.g Chronic
bronchitis and emphysema).
Other respiratory changes that occur with sustained physical exercise include:
-
slight increase in FEVi (Force Exp. Volume in one (1) second)
-
slight increase in MVV (Max Voluntary Ventilation)
-
large increase in VC (Vital Capacity)
-
large increase in MSVC(Max Sustained Ventilatory Capacity)
-
increased respiratory muscle strength and endurance
Functional residual capacity changes with exercise and the changes are such that the capacity to
achieve greater tidal Volume is enhanced (Sharratt et at 1987)
The increase in vital capacity, force expiratory volume, and functional residual capacity, the
improvement in ventilation and perfusion as well as the increase in respiratory muscle strength and
endurance that occur with training are of great benefit to the respiratory system.
SUMMARY OF THE BENEFITS OF EXERCISE
In a more general sense, I worked extensively on body functional changes and benefits
following physical exercise. It is known that exercise brings on a state of fitness and
“look good feeling” or “feel good effect”. When you exercise, the substances released
28
in the body make you feel happy, self confident and relaxed. Your personality and stature
are enhanced and you are better appreciated by other people. My researches were in a
more specific sense on the effect of exercise on the cardiovascular and respiratory systems.
I established a link between exercises and cardiovascular and respiratory fitness (Iyawe,
1993). Other workers have shown it to be true that exercise is extremely beneficial to our
body functions and helps us to live a healthy life. The Book of Wisdom, the Holy Bible
which speaks on all matters of life, admonishes that body exercise profits (1Tim 4:8).
Hence we all need to exercise.
A carefully planned exercise programme:
(1) results in higher fitness levels in healthy individuals
(2) slows down the decrease in functional capacity of the elderly
(3) reinvigorates those who have been ill or have chronic disease.
More specifically, we have established significant decreases in B.P and total serum
cholesterol (but increase in High Density Lipoprotein) in Nigerian hypertensives who
performed graded exercises regularly (Iyawe, Ighoroje, and Iyawe, 1996). Other benefits
of exercise especially on the heart and lung and other allied systems are outlined (Iyawe,
2000).










mild increase in heart muscle size (hypertrophy) and pumping efficiency.
decrease in Heart Rate and increase in Stroke volume at rest.
improved coronary circulation (i.e. blood flow to heart muscle)
decreased O2 demand by the heart
efficient O2 utilization by the heart.
increased vital capacity of the lung
improved gas exchange in the lung.
reduced clotting tendency
destruction of blood clots in those who are predisposed.
reduction in blood pressure, an important risk factor in cardiovascular diseases and
stroke.
In addition to these cardiovascular and respiratory changes, exercise is of benefit to all the
organs and systems of the human body.
29
For Example






Exercise lowers blood glucose levels (of great benefit in Diabetes Mellitus)
Exercise counteracts weight gain and obesity- a risk factor for both diabetes and
coronary heart disease.
Exercise improves lipid profile; i.e. lowers triglyceride levels and raises levels of high
density lipoproteins.
Exercise strengthens muscles, bones and joints (effective in rehabilitating stroke
patients, combating arthritis, and preventing osteoporosis in the elderly).
Exercise improves the immune system and may reduce the risk of developing
cancers e.g. colon, prostate and breast cancer.
Exercise improves memory and helps to prevent mental decline (Alzheimers
Disease) in the elderly.
Because of the numerous benefits of exercise to the body, it is recommended
that physical exercise should be a part of our daily life style; it should be given top
priority among our daily routines. Also new evidence is emerging that age is no barrier to
the benefits accruing from exercise and that physical activity adds years to life, even for
octogenarians (Jacobs J.M. 2009). Working with the elderly in Israel, Jacobs found that
people who had been sedentary but became active, even those who started when they
were well into their 80s, cut their risk of dying and lengthen the amount of time they were
able to live on their own. (Jacobs J.M. 2009). However, it is emphasized that everyone,
especially adults, going to get involved in exercise must as a matter of precaution do
a medical examination and be certified okay.
For exercise to be of significant benefit, it is again emphasized that it must be continuous,
regular and adequate. Even if it is a mild exercise like a walk around the house, a stroll
along the street or a run around the field, it must be done at least 4 times a week. Needless
to say that exercises like running, cycling, swimming, tennis, golfing are more beneficial. If
exercise is so beneficial, why are we becoming more and more a sedentary people? Who
will be the next person in this audience to enlist in a regular exercise regime? Tell your
neighbor – I will be the next. But please, start gradually and do a medical exam, now and
again. Obviously, exercise can be used as a preventive instrument, a therapeutic
procedure to improve cardiac performance as well as a diagnostic method to evaluate the
heart and lung diseases. It is emphasized that, in addition to the heart and lungs, exercise
30
is of great benefit to all organs of the body – the brain, muscles, bones, kidneys, gut, skin
and so on. Let us remember this: many times, it is not how the body looks outside that
the organs look inside. We all need to exercise our bodies.
CONCLUSION.
The heart and the lungs are twinned. This was amply demonstrated in several experiments
during exercise and various interventions like change of posture and use of drugs. They act
together and influence each other. In mild to moderate exercise of short duration, the
pattern of change and the volume of the increases in C.O. were similar to the increases in
V. There was a matching of these changes suggesting that the changes, occur together in
an integrated fashion during the early phase of exercise. The experiments on
hyperventilation and postural changes provided further evidence that C.O. and V are related
and inter-dependent.
Mild doses of caffeine and bitter kola positively affected respiratory and circulatory
functions. However, high doses and frequent use of these drugs adversely affected both
systems. The mildest dose of nicotine (a single and short suck of cigarette smoke)
provoked unfavourable responses as there was narrowing of the airway and sudden
increases in heart rate and BP. The results from experiments on workers in the cement
industry, sawmill, textile mill and so forth were similar. The smokers in these industries
were most affected. They had more cough, sputum production, breathlessness, chest pain
and a profound narrowing of the airway i.e “a reactive airway dysfunctional syndrome”. It
was most intriguing that the industry workers knew little or none of the health risks that they
faced simply because industrial safety standards are low in Nigeria.
The overall benefits of exercise were reviewed. Exercise is of great benefit to the heart and
lungs, and to all the organs of the body. It is profitable to the young, the old and even those
crippled by disease. A well –planned exercise training programme leads to a reduction in
both systolic and diastolic B.P especially in those with mild to moderate hypertension.
Those who maintain their BP at the lower end of normal ranges, that is, a systolic of 120
mmHg or slightly less and a diastolic of 80 mmHg or slightly less have better long term
cardiovascular health than those with higher BP in whom there is a quiet and slow damage
to vital organs. Also, I found significant decreases in total serum cholesterol (but increases
in HDL) in Nigerian hypertensives who did graded exercises regularly. Exercise cleans up
the arteries and prevents them from being clogged. Because of the numerous benefits of
exercise to the body, it is recommended that physical exercise should be a part of our daily
life routines.
31
Finally, to enable people relax and exercise, it is recommended that Local Governments in
the country and governments at all levels should create parks and gardens and mini sports
centres or gymnasia in the different communities in Nigeria.
ACKNOWLEDGEMENTS
I am grateful to God for His grace and love towards me. He created the ladder and kept the
ladder in place for me to climb. God used the following categories of persons to build and
influence my life.
SUPERVISORS
My co-supervisors, Prof Kenneth Saunders and Prof John Widdicombe, both of St.
George’s Hospital Medical School, Tooting, London. They gave me a good foundation in
Research and publication during my Ph.D years.
Dr Fred Imms of St. Thomas’ Hospital Medical School, London in whose laboratory I worked
as a Fellow of the Commonwealth.
POST- GRADUATE STUDENTS
All my post-graduate students over the years especially the following whose works were
used in this treatise
1.
Prof John Igweh (University of Nigeria)
2.
Prof Steve Ufearo (Nnamdi Azikiwe University)
3.
Dr Joshua Ugheoke (Ambrose Alli University)
4.
Dr Maureen Ebomoyi (Uniben)
5.
Dr Fred Agoreyo
,,
6.
Dr Kingsley Ibhazehiebo ,,
7.
Mrs. C. Ejindu
,,
8.
Mr. G.A. Lawton (University of London)
There are others, too numerous to mention
COLLEAGUES IN THE DEPARTMENT OF PHYSIOLOGY AND SBMS.
I have worked in all cordiality with the following fine persons over the last 20-30years; Dr
K.A.Onyia, Prof A.B. Ebeigbe, Prof A.C. Ugwu, Dr A.D.A.Ighoroje, Dr M.I. Ebomoyi, and
32
Prof L.F.O.Obika. I appreciate other junior colleagues in the department and non-academic
staff led by Mr. Nosa Ogbomo (Chief Lab Technologist)
Also, I thank all the staff of the young SMBS, my faculty, for their cooperation, including my
Asst Dean, Dr Hetty Oboh who was one of my collaborators.
TEACHERS
My lecturers in the medical school, some of whom were outstanding.
Among these were Prof T. Belo- Osagie, Prof V.O. Oviasu, Prof A.F. Alli, Prof L.N. Ajabor,
Prof. A.A. obuoforibo, Prof. D.P. Photiades, Prof. L.I.L. Indika, Prof. H. Obianwu, Prof J.O.
Ayanru, Prof Ayo Binitie, Prof J.C. Ebie, Prof U. Osime, Prof R.O. Ofoegbu, Prof G.I.
Akenzua, Prof J.A. Omene, Prof F.M. Diejomaoh, Prof A.U. Oronsaye, and others. My
school teachers and principals represented by Mr. G.P. Alufohai and Mr R.A. Williams
deserve special mention.
SPECIAL FAMILIES
Prof& Prof (Mrs.) Emovon, Elder & Elder (Mrs.) Ted Ogboghodo, Rev (Dr) &
Elder (Mrs.) P.E.F. Obadan, Rev (Dr) & Mrs. E.E. Odigie, Rev (Dr) &Rev (Mrs.)
F.I. Obahiagbon, Rev (Engr) & Dr(Mrs.) E. Egbagbe, Pastor & Pastor (Mrs.) S.
Ogbebor-my dear cousins, Prof. Grace Alele-Williams (former VC Uniben), Mr. &
Mrs. Pat Ehimwenma, Mr. and Mrs. Retin Akemien, Dr & Mrs. F.E. Ihama,
Brig(Dr) & Mrs. F. Osho, Prof & Dr (Mrs.) Nosa Eghafona, Rev (Barr) & Dr
(Mrs.) Ezekiel Omeni, Engr & Dr (Mrs.) Dele Uduehi, Prof & Mrs. A.G.
Onokerhoraye(former VC Uniben), Prof & Dr (Mrs.) Chuks Eboka, Prof & Mrs. E.
Onibere, Prof & Barr (Mrs.) E.A.C. Nwanze (former VC Uniben), Rev (Dr) & Dr
(Mrs.) L.O. Udi, Rev (Dr) & Mrs. M.A. Ohiorenoya, Dr & Rev (Dr) Mrs. V.
Aladeselu, Barr & Mrs. M.C. Onosode, Dr & Mrs. D. Okiy(Executive director
NIFOR), Prof & Mrs. A.O. Ilesanmi(CMD, UCH), Prof &Mrs. Michael
Ibadin(CMD, UBTH), Prof & Mrs. U. Okoli, Prof & Mrs. Yomi Odekunle, Ven &
Mrs P. Ayeni and many others.
MATERNAL AND PATERNAL UNCLES
Engr D.O. Uhimwen, Mr. A.I. Aigbekaen, Mr. Ojo Munson, Barr. F.I. Osemwegie, Surv. (Dr)
F.U.Iyawe, Deputy Comptroller Gen. A.O. Iyawe(rtd) and Arc P.A. Iyawe. They inspired and
fired me in my academics. I appreciate the Okundia Ezomo family now headed by Mr.
Solomon Okundia.
PARENTS
My parents, both late, Mr Willams Iyawe and Mrs Victoria Iyawe who gave me a good name
and made extreme sacrifice to train me. In their absence, I recognize the presence of my
33
siblings, Mrs Obaze, Mrs Ogah, Mrs Ogunsuyi, Ebuwa, Benjy and Robert in the USA. I
thank all my in-laws
SPIRITUAL MENTOR
ArchBishop Benson Idahosa who always encouraged me and taught me Biblical principles.
He promoted me and prophetically started calling me Professor while I was still a Senior
Lecturer. I recognize others in this University whom he also mentored and we grew up
together in the church;
Profs Okhuoya, Gbenedio, Ibhadode, Idu, Izedonmi, Aisien, Ogboghodo, Egbagbe,
Umweni, Akpata, the Josephs, the Akhigbes, just to mention a few. I thank my pastor,
leader of CGMI and mother in Zion, Mama M.E. Benson-Idahosa for her prayers, counsel
and support. I thank all my co-pastors and members of CGMI present here.
NUCLEAR FAMILY
I salute the Love of my life, the one and only, my wife, Rev (Mrs) Helen O. Iyawe, a Director
of Higher Education in the Ministry of Education. As her name is – Okhuosuri or “ one in a
million”, she has indeed been unique in many ways. After over 30 years of marriage, she
has remained the honey in my coffee.
I thank God for giving us 5 intelligent children. They are a source of joy to us. The 5 godly
seeds are here – Dr Osahon, Dr Ikponmwosa, Mr Osama, Engr Idahosa and Miss Isoken
who is a final year engineering student in the University of Port Harcourt.
Also, I thank all those who assisted with typing the manuscript – Barr (Mrs) Aigbe, Victoria
Adubor, Moye Orhue and Rev. H. Ihongbe. Dr. G. Eze of Anatomy Dept. and Dr. G.
Akinlabi, my Ph.D students were helpful with the figures.
Finally, I thank the University of Benin for giving me in-service-training and the Association
of Commonwealth Universities for the Scholarship to do my Ph.D.
Mr. Vice Chancellor, sir, Principal Officers, members of Senate, distinguished audience, I
am done. Thank you for attending the lecture and for your patience.
God bless you and grant you journey mercies as you go to your homes.
TO GOD BE THE GLORY
34
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37
BIOGRAPHY OF AUTHOR
Vincent Imagbovomwan IYAWE joined the services of the University of Benin
in 1980. He attended Ekhaguere Primary School and Garrick Secondary School,
both in Benin, Hussey College, Warri, University of Ibadan, University of Benin,
University of London (St. George’s Hospital Medical School), and University of
Edinburgh. He obtained MBBS (Benin) Ph.D (London) and Dip Sports Medicine
(Edinburgh). He did his NYSC at Alvan Ikoku College of Education, Owerri
(1979-80). He was appointed Lecturer II in 1980, and Lecturer I in 1985. He was
promoted to Senior Lecturer in 1988 and Associate Professor in 1991.
He took sometime off in the mid-1990s to do research and teach outside Nigeria.
Between 1994-98, during his sojourn abroad, he was a visiting Professor at St
Thomas’ Hospital Medical School, London; Al-Quds University, Jerusalem; and
Women’s Medical College, Dubai. He returned to Uniben in 1998 and was
appointed professor in 2000. He has over 100 publications in reputable local and
international journals. Currently, he is Editor-in-Chief of the Journal of Medicine
and Biomedical Research. He is a reviewer for the British Journal of Sports
Medicine and Nigerian Journal of Physiological Sciences, among others. He has
supervised many students up to the Ph.D level. He is a member of several
professional and scientific organisations. For example, he is a member of the
Nigerian Medical Association, Physiological society of Nigeria, Medical Research
Society (U.K), European Society of Clinical Respiratory Physiologists, British
Association of Sports and Medicine, etc. He was a sports physician to the
Commonwealth Games Federation (1984-86).
He excelled in the University and was a National and University Scholar and later,
a Commonwealth Scholar and Fellow. He is an External Examiner and Assessor to
all first generation Universities in Nigeria, and serves regularly as chairman or
team member on NUC and Medical Council accreditation teams. He has served on
pioneering committees to set up two new medical schools, one of them in Israel.
Prof Iyawe has been H.O.D at various times since 1989. He was Asst Dean
(1989-1993). Currently, he is Dean of School of Basic Medical Sciences and
Deputy Provost of the College of Medicine. Recently, he held the position of
Provost in an acting capacity. He has been a member of the University Senate,
College Academic Board, and Appointment and Promotions Committee at all
levels. He has served on several other College and University Committees and
Boards e.g P-G, Admission, Interfaculty Transfer, and Sports. He has been
38
Chairman of Students Disciplinary Committee, Chairman Ethical Committee, and
Chairman of various investigation panels.
He was a Hall Warden and later Hall Master of Clinical Hostel. He was Chairman,
Centre for Part-Time Programmes. A former external member of Council,
Ambrose Alli University, he is currently a member of Uniben Governing Council,
elected from Senate. He chairs the Council committee on Uniben/Edo state Tax
reconciliation. Also, he is a consultant and adviser to Benson Idahosa University,
Benin City. He was formerly a member of Edo state Post-Primary Education Board
and University of Benin Teaching Hospital Management Board.
Prof Iyawe is a Senior Pastor and Zonal Coordinator, Church of God Mission Int.
He was a close associate of Late Archbishop Benson Idahosa. He was formerly
the Chairman of the Board of Administration of the Church and Faith Mediplex,
the Hospital arm of the Church. He is a patron of Scripture Union and Trustee
of NCGF Tract House. He was a general secretary of the Nigerian Christian
Graduate Fellowship and a past President of the Fellowship of Nigerian Christian
Doctors. A marriage counsellor, he is married to Rev (Mrs) Helen O. Iyawe and
they are blessed with five children, four males, Osahon, Ikponmwosa, Osama,
Idahosa and one female, Oyenmwen.
39
CONCLUSION.
The heart and the lungs are twinned. This was amply demonstrated in several experiments during
exercise and various interventions like change of posture and use of drugs. They act together
and influence each other. In mild to moderate exercise of short duration, the pattern of change
and the volume of the increases in C.O. were similar to the increases in V. There was a matching
of these changes suggesting that the changes occur together in an integrated fashion during the
early phase of exercise. The experiments on hyperventilation and postural changes provided
further evidence that C.O. and V. are related and inter-dependent.
Mild doses of caffeine and bitter kola positively affected respiratory and circulatory functions.
However high doses and frequent use of these drugs adversely affected both systems. The
mildest dose of nicotine (a single and short suck of cigarette smoke) provoked infavourable
responses as there was narrowing of the airway and sudden increases in heart rate and BP. The
results from experiments on workers in the cement industry, sawmill, textile mill and so forth
were similar. The smokers in these industries were most affected. They had more cough,
sputum production, breathlessness, chest Pain and a profound narrowing of the airway i.e a
reactive airway dysfunctional Syndrome. It was most intriguing that the industry workers knew
little or none of the health risks that they faced simply because industrial safety standards are
low in Nigeria.
The overall benefits if exercise were reviewed. Exercise is of great benefit to the heart and
lungs, and to all the organs of the body. It is profitable to the young, the old and even those
crippled by disease. A well –planned exercise training programme leads to a reduction in both
systolic and diastolic B.P especially in those with mild to moderate hypertension. Those who
maintain their BP at the is, a systolic of 120 mmttg or slightly less and a diastolic of 80 mmttg or
slightly less have better long term cardiovascular health than those with higher BP in whom there
is a quiet and slow damage to vital organs. Also, I found significant decreases in total serum
cholesterol (but increases in HDL) in Nigerian.
Hypertensives who did graded exercises regularly. Exercise cleans up the arteries and prevents
them from being clogged. Because of the numerous benefits of exercise to the body, it is
recommended that physical exercise should be a part of our daily life routines.