The Circulatory System And Exercise

What Happens To The Heart During Exercise?

Task

• Think of as many different responses your body has during exercise!

• 5 minutes and list them NEATLY!

• Write the heading Responses to Exercise

The Heart and Cardiovascular System

• The Heart is a 4 chamber organ. Two Atria and Two Ventricles.

• HEART RATE – The number of times your heart beats in a minute.

• STROKE VOLUME – The amount of blood pumped by the heart in one beat.

• CARDIAC OUTPUT – The amount of blood that leaves the left Ventricle in one minute.

• To Calculate :

Cardiac Output = Stroke Vol x Heart Rate

Blood Vessels

There are 3 main types of blood vessels that carry blood around the body

• Arteries (Oxygenated blood)• Capillaries• Veins (Deoxygenated blood)

Arteries are the largest blood vessel in the body, then Veins and the smallest are capillaries

Diagrams of Blood Vessels

The Movement of Blood Around the Body

Blood with a poor oxygen supply is pumped to the lungs

Oxygen is transferred into the blood at the lungs and travels to the heart

The heart pumps blood around the body delivering oxygen to the working muscles

Once the oxygen has been delivered to the body and waste products have been collected the blood returns to the heart

To work effectively the Heart and Lungs need to work together smoothly

Remember!

Oxygen-Loaded blood goes into the Left side of the heart.

Oxygen-pooR blood goes into the Right side of the heart.

Recap From Last Lesson

• What is-• Heart Rate• Stroke Volume• Cardiac Output• The Heart• What are the 3 main blood vessels. List them

according to size (largest first)• Describe the movement of blood around the body

How can we measure Heat Rate?Take your Pulse at…..

• The Carotid Artery (Where is this?)

• The Radial Artery (Where is this?)

As the Heart beats the Artery walls expand, then contract and this is called a PULSE.

• Why do we never feel for a pulse using a thumb?

• What is your Resting Heart Rate now?

• Average HR is around 72bpm (60-80bpm). Top athletes?

• What factors may effect Heart Rate?

How Blood is Pumped Around the Body

1. The arterioles branch into tiny tubes called capillaries. The thin walls allow food and oxygen to pass out to body cells, and carbon dioxide and other waste to pass in. (This happens in the muscle)

2. The artery walls are made of muscle and elastic tissue. They stretch when blood is pumped in, then contract, squirting it along.

3. From the venules it flows into a vein, which carries it back to the heart.

4. The heart pumps blood at high pressure into the arteries.

5. The artery branches into smaller tubes called arterioles.

6. Next the blood flows into larger tubes called venules. It has given up its oxygen. It is deoxygenated.

How Blood is Pumped Around the Body

4) The heart pumps blood at high pressure into the arteries.

2) The artery walls are made of muscle and elastic tissue. They stretch when blood is pumped in, then contract, squirting it along.

5) The artery branches into smaller tubes called arterioles.

1) The arterioles branch into tiny tubes called capillaries. The thin walls allow food and oxygen to pass out to body cells, and carbon dioxide and other waste to pass in. (This happens in the muscle)

6) Next the blood flows into larger tubes called venules. It has given up its oxygen. It is deoxygenated.

3) From the venules it flows into a vein, which carries it back to the heart.

What Changes Occur In The Body During Exercise?

• There is more Carbon Dioxide in the blood due to increased cellular respiration.

• The lungs work harder to remove it and replace it with Oxygen.

• The Brain tells the Heart to beat faster so HR increases.

• Cardiac Output rises as more blood is pumped to the muscles.

These are all short term effects of exercise/activity

Other Changes you will experience….

• Blood is shunted to where it is needed. (Vascular Shunt). Blood is diverted to the working muscle as a priority and is limited to other areas of the body like the stomach

. • Exercise generates Heat so the

blood heats up. The body moves more blood near to the skin to cool it down. As a result your skin reddens.

• You sweat which helps to cool you down by evaporation.

• Again these are short term effects

The Long Term Effects of Exercise on the Circulatory system

• The Heart is a Cardiac Muscle, when we regularly exercise or train muscles they grow and become stronger. This means:

1. The amount of blood pumped from the heart in one beat will increase (Stroke volume)

2. The total amount of blood pumped in one minute will increase (Cardiac output)

3. Resting heart rate will lower as the heart will pump the blood as required in fewer beats.

• The more blood that can be pumped the more oxygen it can carry to the muscles that require it.

Regular exercise

Small HeartLarger stronger Heart

LONG TERM LONG TERM EFFECTS OF EFFECTS OF TRAININGTRAINING

CIRCULATORY CIRCULATORY IMPROVEMENTSIMPROVEMENTS

CARDIAC CARDIAC (HEART) (HEART)

RESPONSERESPONSE

RESPIRATORY RESPIRATORY RESPONSERESPONSE

EFFECT ON TENDONS, EFFECT ON TENDONS, LIGAMENTS AND LIGAMENTS AND

BONESBONES

RECOVERY RECOVERY RESPONSERESPONSE

Long Term Effects cont’d

• The number of red blood cells increase to cope with the demands of carrying extra oxygen. (Altitude training).

• The capillary networks in muscles start to grow more and more branches and are therefore able to transport more blood. (Capilliarisation)

AFTER AEROBIC TRAININGAFTER AEROBIC TRAINING

CIRCULATORY IMPROVEMENTSCIRCULATORY IMPROVEMENTS

INCREASED BLOOD VOLUMEINCREASED BLOOD VOLUME (RBC) – increased levels (RBC) – increased levels of haemoglobin. Increased oxygen carrying capacity of the of haemoglobin. Increased oxygen carrying capacity of the bloodblood

ImprovedImproved REDISTRIBUTION OF BLOODREDISTRIBUTION OF BLOOD to active to active muscles.muscles.

INCREASED CAPILLARY NETWORKINCREASED CAPILLARY NETWORK surrounding the surrounding the muscles, therefore more blood is transported to the muscles.muscles, therefore more blood is transported to the muscles.

ARTERIAL WALLSARTERIAL WALLS becomebecome MORE ELASTICMORE ELASTIC – – allowed allowed greater flow of blood to the working muscles. greater flow of blood to the working muscles.

THE CARDIAC (HEART) RESPONSETHE CARDIAC (HEART) RESPONSE

HEARTHEART becomesbecomes andand ..

in resting heart rate.in resting heart rate.

Increased thickness and strength of the Increased thickness and strength of the VENTRICULAR WALLVENTRICULAR WALL causes an increase in thecauses an increase in the STROKE STROKE VOLUMEVOLUME and a lowering of the resting pulse rate.and a lowering of the resting pulse rate.

Larger stroke volume also means that there is an increase in Larger stroke volume also means that there is an increase in maximalmaximal OUTPUT OUTPUT..

After exercise, the Heart Rate returns back to its normal After exercise, the Heart Rate returns back to its normal resting levels faster than it did before trainingresting levels faster than it did before training ( (IMPROVED IMPROVED

THE CARDIAC (HEART) RESPONSETHE CARDIAC (HEART) RESPONSE

HEARTHEART becomesbecomes LARGERLARGER andand STRONGERSTRONGER..

DECREASEDECREASE in resting heart rate.in resting heart rate.

Increased thickness and strength of theIncreased thickness and strength of the LEFT LEFT VENTRICULAR WALLVENTRICULAR WALL causes an increase in thecauses an increase in the STROKE STROKE VOLUMEVOLUME and a lowering of the resting pulse rate.and a lowering of the resting pulse rate.

Larger stroke volume also means that there is an increase in Larger stroke volume also means that there is an increase in maximalmaximal CARDIAC OUTPUTCARDIAC OUTPUT..

After exercise, the Heart Rate returns back to its normal After exercise, the Heart Rate returns back to its normal resting levels faster than it did before trainingresting levels faster than it did before training ( (IMPROVED IMPROVED RECOVERYRECOVERY).).

RESPIRATORY RESPONSERESPIRATORY RESPONSE

MoreMore ALVEOLIALVEOLI in the lungs can be utilised – greater in the lungs can be utilised – greater surface area for gaseous exchange.surface area for gaseous exchange.

GreaterGreater CAPILLARISATIONCAPILLARISATION of the alveoli – oxygen of the alveoli – oxygen transfer further enhanced.transfer further enhanced.

THE EFFECT ON TENDONS / LIGAMENTS / CARTILAGETHE EFFECT ON TENDONS / LIGAMENTS / CARTILAGE

TheThe TENDONSTENDONS, , BONESBONES andand LIGAMENTSLIGAMENTS get stronger to get stronger to cope with the increased load.cope with the increased load.

CARTILAGECARTILAGE may increase to cope with the increased may increase to cope with the increased impact.impact.

RECOVERY RESPONSERECOVERY RESPONSE

This is a combination of the improvements witnessed in theThis is a combination of the improvements witnessed in the HEARTHEART andand LUNGSLUNGS..

The effect of this improvement is to allow moreThe effect of this improvement is to allow more OXYGENOXYGEN to become available forto become available for RECOVERYRECOVERY more rapidly at the end more rapidly at the end of exercise.of exercise.

Coupled with the improved transportation of oxygen is the Coupled with the improved transportation of oxygen is the improved transport ofimproved transport of CARBON DIOXIDECARBON DIOXIDE from the working from the working muscles to the lungs.muscles to the lungs.

Therefore improving the process ofTherefore improving the process of LACTATE LACTATE REMOVALREMOVAL..