The Benefits of exercise on the CV System.

Mr. P. Leighton

GCSE PE

Today’s Session…

• All of you: will understand the benefits of regular exercise on the CV system.

• Most of you: Will understand the key terms Cardiac Output and Stroke Volume when talking about the CV System.

• Some of you: Will be able to attempt the exam style question at the end of the session.

Recap: 5mins- So what happens to the body during exercise?

BreathingFaster and

Deeper

Muscles begin To ache

Sweating starts

Blood Pressure Increases

Adrenaline occurs

Increased HR

EXERCISECAUSES…

While all this is happening…

• Lactic acid builds up during exercise.

• It is poison to you body- it can cause cramp and eventually stop muscles working.

• The reason it is used is because Glycogen stores in muscles are depleted.

• Athletes must rest to allow the blood to bring fresh O2

So we can produce energy…

With Oxygen in AEROBIC RESPIRATION

Without Oxygen in ANAEROBIC RESPIRATION

So what happens if you carry on exercising?

• Decrease in HR.

• Heart recovery rate increases

• Increased Stroke Volume

• Cardiac Output increases.

• Blood Pressure is reduced.

• Healthy arteries and veins

Decrease in Heart Rate…

• Resting HR gives an indication of fitness.

• The heart is a muscle- the fitter you are the bigger and stronger it gets.

• It can then supply the same amount of blood with fewer beats.

Heart Rate Recovery Increases...

• The faster the recovery rate, from WORKING to RESTING HR, the fitter the person.

• Christine Ohuruogu working HR could be like yours- her resting HR is as low as 40bpm

Increased Stroke Volume…

• Stroke Volume is the amount of blood pumped by the heart per beat.

• When a person exercises regularly, Stroke volume increases; both at rest and at work.

• At rest it can be 85ml.

• At work stroke volume could be 130ml: half a cup of water every beat!

Cardiac Output Increases…

• Cardiac Output is the amount of blood ejected from the heart in one minute.

• It is governed by the heart rate (pulse) and stroke volume.

• The equation to calculate cardiac output is…

Cardiac Output

(CO)

Stroke Volume

(SV)

Heart Rate

(HR)

Blood Pressure Reduces…• Regular exercise reduces blood pressure.

• Exercise can help with weight loss.

• Extra weight puts strain on the heart and increase blood pressure.

• Factors which can affect blood pressure are age, sex, muscular development, stress and tiredness.

• Is there anything else that can affect it?

Healthy Veins and Arteries…

• Fitness increases the number of capillaries within the heart muscle.

• It also makes blood vessels more flexible and efficient.

• What happens if you have a heart attack?

Exam Question…

Recap…

• All of you: will understand the benefits of regular exercise on the CV system.

• Most of you: Will understand the key terms Cardiac Output and Stroke Volume when talking about the CV System.

• Some of you: Will be able to attempt the exam style question at the end of the session.