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 System

What 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 Volume

SV = 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/beat

X X X

HR 70 beats/min

130 beats/ min

= = =

COElite REST MAX

EXERCISE

SV 100ml/beat 200ml/beat

X X X

HR 40 beats/ min 180 beats/ min

= = =

CO

heart 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 rate

With 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. Systolic

2. Diastolic

Research 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 hypertrophy

2. Increased SV

3. Increased CO

4. Decreased resting HR

5. Capillarisation

6. Increase in blood volume

7. Reduction in resting BP

8. Decreased recovery time

9. 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