1. EFFECTS ON MUSCULAR
SYSRTEM
A skeletal muscle is composed of
thousands of fibres bound together with connotive tessues. Regular and heavy
muscular work thickens and toughens the sarcodema (wall of the muscle fibre)
and increases the amount of connective tissues that bound them together. This
change enlarges the individual muscle fibres and increases circulatory and
respiratory activities.
2.
GAIN IN STRENGTH: Strength is
defined as the ability to exert force or tension against a resistance. The
structural changes in the sarcolemma, fibres and capillaries as a result of
exercise facilitates adequate circulation through the muscle tissues with more
available fuel and oxygen for the release of greater energy.
3.
Greater muscle endurance
4.
Greater capillary network
5.
Fast nerve impulses from the
motor-end-plate to the motor-nerve-ending
6.
Increase in phosphor-creative
content
EFFECTS ON RESPIRATION
1.
Greater expansion of chest
2.
Greater air volume in the chest
cavity
3.
Slower rate of breathing
4.
Greater concentration of oxygen
5.
Greater exposure of blood to
oxygen
6.
Greater depth of chest cavity
during breathing
The purposes of respiration are to provide oxygen for metabolism in
the body and to eliminate carbon dioxide resulting from oxidation. With
exercise, the respiratory mechanism is adjusted to carry out its functions
effectively.
EFFECTS ON THE
CARDIO-VASCULAR SYSTEM
During exercise, there is increased
oxygen requirement of the contracting muscles.
The blood therefore carries nutrients
to and waste from all parts of the body. The heart in large part supplies the
necessary force to propel the blood.
1.
Increase in blood circulation
2.
Greater output of blood
3.
Greater expansion and
contraction of the heart
4.
Enlarged heart
5.
Cardiac muscle becomes
strengthened and toughed
6.
Reduction in lactic acid
formation in the muscles. Greater output of work
EFFECTS ON STROKE
VOLUME
Stroke volume is the volume of blood ejected by each ventricle of
the heart during a single systole. A normal individual at rest has about seven
litres of blood in circulation. Research on such Olympic athletics, e.g. De
Mer, the great Marathon runner, shows that his heart pumped twenty-two litres
of blood as compared to 10.2 litres in an untrained person.
1.
Increase in stroke volume
2.
Better diastolic filling of the
heart
3.
Increase in arterical pressure
4.
Increase in capacity of heart
5.
Greater ejection of blood
EFFECTS ON PULSE RATE
Pulse rate is the number of heart beats per minute. In a normal person,
it is between 70-80 per minute. (72) On the average.
1.
Low pulse rate
2.
Rapid return to normal pulse
rate
EFFECTS ON BLOOD (R.B.C) (ERYTROCYTES)
On the average, the
number of red blood cells (R.B.C) in the blood of a resting man is about
5million per mm
1.
Increase in R.B.C formation
2.
Greater carriage of oxygen by
haemoglobin
3.
Greater release of energy for
more work
4.
Better development of red bone
marrow
5.
Lower formation of lactic acid
6.
Reduction in the osmotic
resistance of R.B.C due to rise in body temperature
ON W.B.C (LEUCCOCYTES)
1.
Increased in the number of
W.B.Cs
2.
Decreased in foreign materials
invading the blood
ON THE DIGESTIVE SYSTEM
1.
Increased demand for appetite
2.
Increased in digestion
3.
Early removal of waste products
from the stomach
4.
Increased in the persitalic
action of the alimentary canal due to fast secretion of acid
ON EXCRETORY SYSTEM
1.
Early removal of sweat by the
skin; carbon dioxide by the lungs and urine by the kidney
2.
Dilation of vaso-dilators for
the release of body heat
3.
Constant body temperature
SOME DIFFERENCES BETWEEN A TRAINED AND UNTRAINED
PERSON
TRAINED PERSON
|
UNTRAINED PERSON
|
1.
Lower oxygen consumption
|
Higher oxygen consumption
|
2.
Lower pulse rate
|
Higher pulse rate
|
3.
Large stroke volume
|
Low stroke volume
|
4.
Less rise in blood pressure
|
Greater rise in blood pressure
|
5.
Greater crythrocyte and
leuccocyte count
|
Lower erythrocyte formation
|
6.
Slower rate of breathing
|
Quicker rate of breathing
|
7.
Lower rate of lactic acid
formation
|
Faster rate of lactic acid formation
|
8.
Faster return to normal of
blood pressure and heart rate
|
Slower return to normal
|
9.
Toughened, thickened and
stronger sarcolemma
|
Weak sarcolemma
|
10.
Greater expansion and depth
of chest cavity
|
Little expansion of chest cavity
|
11.
Greater call for appetite
|
Loss of appetite
|
12.
Fast elimination of wastes
from the skin, lungs and kidney
|
Slow elimination of wastes
|
SPORTS AND DRUGS-(ERGOGENIC AIDS)
The rewards of
competitive sports-financial, personal and national prestige are the cause of
determination to win. Drugs are therefore used to improve performance. However,
they have very little effect on performance.
Ergogenic simply
means ‘’work producing’’. The aids can therefore be defined as any substance or
suggestion taken to produce more work. Ergogenics is therefore a scientific
term that describes substance that some athletes ingest, inject, inhale or
apply to the body or skin in order to have beneficial effect on their physical
performance. These aids diverse and have effects that can either be positive or
negative.
REASONS FOR TAKING DRUGS
v Alteration of mood
v Relief of pain or anxiety
v Postpone fatigue
v Promote social adeqatecy and performance
v Continue illusory experience outside reality
v Faster speed
v Greater strength
v Long endurance
v Part of group behaviour
v Vehicles for acting out adolescent rebellion
v Alertness
v Precision
v Calmness
v Accuracy
All authorised
drugs are prescribed for specific illnesses by a physician. He accepts full
responsibility for all effects of the drug, the doses are controlled, and the
supply is limited.
CAUSES OF ERGOGENIC AIDS
v Nutritional- foods and nutritional supplements to athletes diet
v Mechanical- use of oxygen and heart
v Pharmacology- use of drugs hence doping or therapy
v Music
v Motivation
TYPES OF ERGOGENIC AIDS
STIMULANTS- used to delay the onset of fatigue. Make the athlete
look more alert, become physically powerful and improve performance.
Analeptics and psycho tonics
PSYCHOTONICS: They have their effects on the (brain) and the central
nervous system (CNS). The most important are the ampheltamins. E.g. caffeine,
ground in beverages like tea, coffee, cocoa and cola.
They are taken to increase psychological tone, increase motor
activity and to delay feelings of fatigue. The use involves excessive
expenditure of energy, stimulates the metabiolism of skeletal muscles and
increases cardiac output.
EFFECTS:
a)
decreases in pulse rate;
b)
decrease in blood pressure
c)
decreases in respiratory rate
d)
produces nervousness
e)
Improper metabolism of
carbohydrates and proteins needed for energy protection.
f)
Vasoconstriction of the blood
vessels.
ANALEPTICS
They set the cardiac and respiratory regulating mechanisms.
They include drugs of the adrenalin series e.g. epherdrine,
coramine, camphor
SEDATIVES
These are the destimulants or depressants. They are used in events
requiring calmness, precision and control e.g. shooting with pistol, rifle or
bow and arrow. Examples are -diazepam, ethyl alcohol- used in the form of
brandy or rum.
ANABOLIC STEROIDS: they resemble the male sex-hormone, testosterone and are used for
promoting muscular developments in sports. Mostly used by shot putters weight
lifters, boxers and in the events requiring strength and powers. Examples are
dainabol, android, cortisome, and testosterone.
EFFECTS:
·
Liver disfunctioning
·
Sterility in man
·
Male-pattern baldness
·
Masculinity in women
·
Virility growth
·
Liver cancer
·
Deepening of voice in women
ALCOHOL: Widely abused drug in modern societies.
·
Large doses depress in CNS
·
Acts on higher brain centres
that affect decisions, judgement and memory
·
Control of lower brain centre
is lost
·
Reaction time is slowed
·
Athletic performance is
impaired
·
Lost of control in automobile
accidents
MARIJUANA/CANABIS
Marijuana smoking does not improve athletic performance but poses a
great risk to the lungs and heart similar to that of tobacco
EFFECTS
·
Speeds up pulse rate
·
Raises blood pressure
·
Constricts blood vessels
·
Interferes with the ability of
the R.B.C to release oxygen to the body tissues
·
Lung cancer
Heart diseaseBY: V.K TAY
TUTOR SOGAKOFE SENIOR HIGH SCHOOL,SOGAKOFE VOLTA REGION(P.E DEPARTMENT)
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