TOPIC 1 - Lesson 1: The effects of training on the heart and the cardiac conduction system

Question 1

Define Diastole.

Answer 1

Term used to describe the relaxation phase of the cardiac cycle. The heart ventricles are relaxed and fill with blood.

Question 2

Define Systole.

Answer 2

Term used to describe the contraction phase of the cardiac cycle - the ventricles contract and pump blood to the arteries.

Question 3

Define Stroke Volume (SV).

Answer 3

The volume of blood that leaves the heart during each contraction.

Question 4

Define Health.

Answer 4

A state of complete physical, mental and social well being and not merely the absence of disease and infirmity/injury.

Question 5

Define Fitness.

Answer 5

The ability to meet and cope with the demands of the environment.

Question 6

Define Physical Activity.

Answer 6

Being active and taking part in exercise - can directly benefit your health and well being.

Question 7

Define Heart Rate (HR).

Answer 7

The number of times the heart beats per minute.

Question 8

Define Anticipatory Rise

Answer 8

Slight increase in heart rate usually before activity starts due to the expectation of exercise.

Question 9

Define Cardiac Output.

Answer 9

The volume of blood pumped out by the heart ventricles per minute.
Q=SV x HR

Question 10

How does exercise and maintaining fitness improve your physical health?

Answer 10

• Cardiovascular and respiratory improvement.
• Increases heart and lung strength.
• Develop more red blood cells.
• Reduces health risk factors - cardiovascular disease, diabetes (type 2), cancers.
• Can influence life span.
• Increase metabolic rate.
• Bone health improvement.
• Weight loss.

Question 11

Parts of the heart.

Answer 11

• Superior vena cava/ Inferior vena cava
• Aorta
• Pulmonary artery
• Pulmonary vein
• Right Atrium/ Left atrium
• Tricuspid valve/ Bicuspid valve
• Chordae tendineae
• Right ventricle/ Left ventricle
• Semilunar septum
• Inter ventricular septum

Question 12

Pathway of Blood.

Answer 12

1. Vena cava (superior and inferior)
2. Right Atrium
3. Tricuspid Valve
4. Right Ventricle
5. Pulmonary Semilunar Valve
6. Pulmonary Artery
7. Lungs
8. Pulmonary Veins
9. Left Atrium
10. Bicuspid Valve
11. Left Ventricle
12. Aortic Semilunar Valve
13. Aorta
14. BODY

Question 13

Individual Differences -
Trained vs Untrained

Answer 13

Trained:
• Training increases number of red blood cells - provides oxygen to the working muscles.
• Cardiac hypertrophy - heart muscle gets bigger and stronger.
• Chambers become stronger - increased stroke volume (more blood ejected).
• Trained person SV = 130-180ml.
• Resting HR = below 40bpm
(bradycardia - term used for those with a resting HR below 40pm).
• Lower HR sub-max.
• Slower HR increase.
• Lower HR during exercise.
• Faster return to resting HR.

Untrained:
• Average person SV = 112ml
• Untrained person resting HR = 90bpm

Question 14

Order of the conduction system.

Answer 14

1 - SAN (sino atrial node)
2 - Atrial systole
3 - AVN (atrio ventricular node)
4 - Bundle of His
5 - Bundle branches
6 - Purkinje fibres
7 - Ventricular systole

Question 15

The heart is described as being myogenic. What does this mean and discuss how the cardiac system works.

Answer 15

The heart is said to be MYOGENIC because it has the ability to generate its own electrical impulses which originate in the heart muscle itself with an electrical signal in the SAN.

• This impulse spreads across the heart like a Mexican wave and is called a WAVE OF EXCITATION.

• This causes ATRIAL SYSTOLE.

• The impulse then passes through the AVN where it is delayed for approximately 0.1s to enable the atria to fully contract before the ventricles contract.

• The impulse then travels through the BUNDLE OF HIS which then divides into two branches (BBUNDLE BRANCHES) and then again into the PURKINJE FIBRES.

• This allows the impulse to spread throughout the ventricles causing them to contract. This is known as VENTRICULAR SYSTOLE.