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LONG TERM EFFECTS OF EXERCISE ON THE BODY SYSTEMSPhysiology of Fitness Andrew Roberts
Long Term Effects of Exercise on the Body Systems What body
systems do we mean?
1. Cardiovascular2. Respiratory3. Energy systems4. Muscular5. Skeletal
6. CREMS
As you exercise regularly your body adapts – you become fitter – more able to cope with the demands of exercise. We are going to look at what changes occur in the heart, lungs, muscle, skeleton and energy systems.
Learning Outcomes Identify the 5 main body systems that
are affected by long term exercise Describe 3 key changes to the
cardiovascular system after long term exercise (e.g. after 6 weeks)
Identify 2 changes to the energy systems as an adaptation to long term exercise
Examine and record our current level of cardiovascular fitness
Long Term Effects of Exercise on the Cardiovascular SystemWhat is the CV system?
The heart and blood vessels of the circulatory system
Task In pairs list what aspects of the
cardiovascular system may change as a result of regular long term exercise?
In fours, compare results and see if you can add to your original list.
Heart Cardiac Hypertrophy
The heart increases in its size and blood volume.
The wall of the left ventricle thickens ..why?to increase the strength potential of its contractions In sedentary, middle aged individuals it may be as high as 100 beats/min.
Normal heart rate (HR) 60-80 beats / min
Elite endurance athlete’s HR 28 – 40 bpm
CV system cont... Increase in Stroke
VolumeSV = The amount of blood
that can be pumped by the heart per beat.
This means the heart can now pump more blood per minute.
Why is this beneficial?Increased blood flow allows
for faster and more efficient delivery oxygen and nutrients
In untrained individuals stroke volume at rest it averages 50-70ml/beat increasing up to 110-130ml/beat beat during intense, physical activity.
In elite athletes resting stroke volume averages 90-110ml/beat increasing to as much as 150-220ml/beat
CV system cont...Increased Cardiac
Output (CO)SV X HR = CO
As SV and HR increase during exercise CO will increase.
In a trained heart both SV and HR have increased capacity.
SV does increase to a point – however the significant increases in CO are caused by a bigger increases in
Untrained
REST MAX EXERCISE
SV 60ml/beat 120ml/beatX X X
HR 70 beats/min
130 beats/ min
= = =CO
Elite REST MAX EXERCISE
SV 100ml/beat 200ml/beatX X X
HR 40 beats/ min 180 beats/ min= = =
COheart rate
4200ml/min 15600ml/min
4800ml/min 36000ml/min
CV system cont...
Discussion
Eg An untrained student’s heart rate was measured at 140bpm while running 6mph on the treadmill
After 6 weeks of exercise (running for 30 mins 3 times per week) I would expect HR to
1. Why?2. What physiological changes would
have occurred?
increasedecrease
CV system cont... Decreased resting
heart rateWith regular training
your resting HR falls.Also your HR returns to
normal quicker after exercise.
How could you measure these improvements over your 6 week program?
Capillarisation Capillary networks
increase to your cardiac and skeletal muscle.
This improves blood supply to the active muscles and improves the muscles’ efficiency
CV system cont... Increase in Blood
Volume Your blood volume is
the amount of blood circulating in your body
It increases as an adaptation to regular exercise
It increases as a result of capillarisation
Reduction in Resting Blood Pressure
What are the 2 measurements of BP?
1. Systolic2. DiastolicResearch shows that the
quicker your BP returns to normal the fitter you are.
How could you measure this?Regular exercise can contribute
to lowering BP.
CV system cont... Decreased
Recovery Time HR recovery is a
measure of how much your HR falls the first minute after exercise.
Fit people can recover more quickly. How?
The CV system has adapted and become more efficient through the demands of regular exercise
Increased Aerobic Fitness
This occurs as a result of what kind of training?
Aerobic training e.g.? Running, cycling... Aerobic fitness refers to
endurance, or the ability to sustain work for prolonged periods.
How can you measure an improvement in aerobic fitness?
Recap
TASK In pairs, recall at least 3 key changes to your CV system as a result of long term exercise?
1. Cardiac hypertrophy2. Increased SV3. Increased CO4. Decreased resting HR5. Capillarisation6. Increase in blood volume7. Reduction in resting BP8. Decreased recovery time9. Increased aerobic fitness
Long Term Effects of Exercise on the Energy System
Task In pairs Exercise can cover a wide
range of meanings ....what exercise are we considering? On a flip chart write exercise in the middle and jot down what exercise means to you.
Type Intensity Frequency
Duration
Long Term Effects of Exercise on the Energy Systems Type Intensity Frequency Duration What systems does our body use to
supply energy to our muscles? ATP-CP Lactic Acid energy system Aerobic Energy system
1-10 secs
10s – 2mins
2 mins +
Long Term Effects of Exercise on the Energy Systems At cellular level
muscles need what to contract?
What adaptations may occur at cellular level ?
1. Increase in level of enzymes for aerobic and anaerobic systems.
2. Increase in size of mitochondria.
Increased use of fat as an energy source
Fat combustion powers almost all exercise at 25% of aerobic power.
Fat oxidation increases if exercise extends to long periods as glycogen depletes
Trained athletes burn more fat as fuel than non-trained athletes.
ATP
Long Term Effects of Exercise on the CV & Energy Systems
Paired Task Identify 2 changes to the energy systems as an adaptation to long term exercise
Describe 3 key changes to the CV system and how you may examine record those changes before and after a 6 week training program
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