1. THE HEART ACTS AS TWO SEPARATE PUMPS RESPONSIBLE FOR 2 CIRCULATORY NETWORKS OF BLOOD VESSELS.

DRAW & LABEL A DIAGRAM TO SHOW THE 2 CIRCULATORY NETWORKS

(5)

RA RV

PULMONARY ARTERY

LUNGS

LV LA

BODY

(VENULES)

(CAPILLARIES)

(ARTERIOLES)

AORTA PULMONARY VEINS

(VENULES)

(CAPILLARIES)

(ARTERIOLES)

2. The amount of blood that the heart manages to pump out a crucial factor during exercise.

Define the terms STROKE VOLUME, HEART RATE & CARDIAC OUTPUT

• HEART RATE – THE NUMBER OF TIMES THE HEART BEATS IN ONE MINUTE

• STROKE VOLUME – THE VOLUME OF BLOOD PUMPED BY EACH VENTRICLE IN ONE CONTRACTION

• CARDIAC OUTPUT – THE VOLUME OF BLOOD PUMPED BY EACH VENTRICLE IN ONE MINUTE / = STROKE VOLUME X HEART RATE (Q = SV X HR)

3. HOW IS CARDIAC OUTPUT INCREASED?

• VENOUS RETURN IS INCREASED

• RELEASE OF ADRENALINE STIMULATES SA NODE

• VOLUME INCREASES WHICH STRETCHES VENTRICULAR WALLS WHICH WILL INCREASE SROKE VOLUME

• SYMPATHETIC NERVE (ACCELERATOR) SPEEDS UP SA NODE

4. THE BLOOD IS RESPONSIBLE FOR SUPPLYING THE VITAL INGREDIENTS NEEDED FOR THE MUSCLES TO WORK , AS WELL AS FOR CARRYING AWAY WASTE PRODUCTS FROM THE WORKING MUSCLES.

HOW ARE OXYGEN & CARBON DIOXIDE TRANSPORTED IN THE BLOOD?

OXYGEN• Red blood cells contain haemoglobin• Haemoglobin has an affinity for 02• 97% of O2 combines with Hb (to form

oxyhaemoglobin)• 3% of O2 dissolves in the plasma

CARBON DIOXIDE• 8% of carbon dioxide dissolves in plasma• 20% of C02 combines with haemoglobin• 72% of C02 dissolves in water to form carbonic

acid

6. DEFINE BLOOD PRESSURE & USING THE CORRECT UNITS GIVE

AN AVERAGE VALUE FOR A YOUNG ADULT AT REST

• BLOOD PRESSURE = BLOOD FLOW X RESISTANCE TO FLOW

• PRESSURE EXERTED BY BLOOD ON WALLS OF BLOOD VESSELS

• 120/80

7. WHY IS GOOD VENOUS RETURN BENEFICIAL TO

PERFORMANCE?

• GREATER VOLUME OF BLOOD RETURNED TO THE HEART

• SV & Q IS DEPENDENT UPON VENOUS RETURN

• GREATER VR WILL INCREASE SV & A LARGER SV WILL INCREASE Q

• GOOD VENOUS RETURN MAINTAINS BLOOD PRESSURE

• MORE BLOOD/OXYGEN WILL BE SUPPLIED TO MUSCLE

8. SKETCH A GRAPH TO SHOW THE HEART RATE OF AN ATHLETE WHO

COMPLETES A 30 MIN AEROBIC TRAINING RUN.

SHOW HEART RATE PRIOR TO THE TRAINING RUN, DURING THE RUN AND

FOR 10 MIN AFTER THE RUN.

• Resting heart rate around 40/90 beats per minute

• Rise in HR prior to exercise/anticipatory rise

• Steep rise at beginning of exercise and Plateau during exercise (115-180b/min range)

• Initial fast fall during recovery

• Followed by gradual decline towards rest value

REST EXERCISE RECOVERY

50

100

150

200

9. DESCRIBE HOW HORMONAL CONTROL IS

USED TO ALTER HEART RATE DURING THE TRAINING RUN

• ADRENALINE/NORADRENALINE IS RELEASED

• STIMULATES THE SA NODE

• INCREASES THE HEART RATE

• ALSO INCREASES STRENGTH OF CONTRACTION/STROKE /CARDIAC OUTPUT.

10. DESCRIBE THE MECHANISMS OF VENOUS

RETURN THAT ENSURE ENOUGH BLOOD IS

RETURNED TO THE HEART DURING THE TRAINING

RUN.

• SKELETAL MUSCLE PUMP (MUSCLES CONTRACT TO SQUEEZE BLOOD BACK TO THE HEART)

• VALVES/DIRECT BLOOD FLOW BACK TO THE HEART/PREVENT BACKFLOW.

• RESPIRATORY PUMP

• BLOOD ABOVE THE HEART WILL RETURN DUE TO THE EFFECT OF GRAVITY

• VENOCONSTRICTION OF VEINS RETURNING BLOOD TO THE HEART.

11. WHY SHOULD THE PERFORMER WARM UP BEFORE THE TRAINING

RUN?

• An increase in muscle temperatureThis allows greater stretch in the muscles/02 dissociates from haemoglobin quicker

• Decreases risk of injury• Nerve conduction quicker• Improves muscle contraction speed/faster

reaction time/ improved co-ordination of antagonistic pairs

• Increase in heart rate/respiratory rate/stroke volume/cardiac output

• Increase enzyme activity• Blood vessels dilate• Reduces blood viscosity so blood flow quicker

12. During exercise more oxygenated blood is required by the muscles.

Define cardiac output and give a maximum value for a 17 year old endurance performer.

Definition:

The total amount of blood ejected from the left ventricle per minute/ Q= SV X HR.

Value:

Range 20 – 40 Litres (per min)

13. Following a training session a coach will require the performer to complete a cool down.

How would a cool down aid the vascular system?

• Flushes out lactic acid/repays oxygen debt.

• Keeps capillaries dilated/maintains blood flow.

• Maintains skeletal muscle pump/respiratory pump

• Prevents blood pooling

• Maintains venous return

• Maintains Stroke Volume/Q

• Maintains blood pressure

14. Describe how blood travels through the heart during the following stages of the cardiac cycle:

DIASTOLE/ATRIAL SYSTOLE & VENTRICULAR SYSTOLE

DIASTOLE • The atria/ventricles/heart are relaxed• Semi lunar valves closed• Blood flows into right & left atrium via • pulmonary vein & vena cava• Pressure rises and forces blood into ventriclesATRIAL SYSTOLE • The atria contract forcing the blood into ventricles• Through AV valves VENTRICULAR SYSTOLE• The ventricles contract• AV valves shut to prevent backflow• Blood forced through pulmonary artery and aorta• Semi lunar valves forced open

15. Whilst exercising a greater amount of blood is ejected during ventricular systole.

Why is this beneficial to performance?

• More oxygen/blood supplied to muscles

• Greater amounts of C02 waste products removed/delay OBLA.

• Delays fatigue/maintains/prolongs aerobic performance