Cardiovascular Exercise Physiology

Question 1

Layer of the heart that is muscle is the ___________

Answer 1

Myocardium

Question 2

_______ divides heart into left and right halves

Answer 2

Septum

Question 3

_______ regulate blood flow between the chambers

Answer 3

Valves

Question 4

_____ system includes the coronary arteries

Answer 4

Coronary circulation

Question 5

Coronary arteries branch directly off the ______, supplying blood to the myocardium

Answer 5

aorta

Question 6

_______ communicates with the heart via Acc. nerve and vagus nerve

Answer 6

medulla

Question 7

2 nerves parasympathetic and sympathetic are ________ & _________

Answer 7

Accelerator nerve & vagus nerve

Question 8

RBC’s are removed by the ______

Answer 8

spleen

Question 9

Measures blood cells over the volume of blood: ______

Answer 9

Hematocrit test

Question 10

What layer of muscle includes * Vasoconstriction
* Vasodilation:
________

Answer 10

Smooth muscle layer

Question 11

Pressure exerted by the blood on the walls of the vessels
– Monitored by _________

Answer 11

Baroreceptors

Question 12

_____ :pressure in arteries when heart contracts

Answer 12

systolic

Question 13

_______: pressure when heart relaxes

Answer 13

diastolic

Question 14

What theory/concept includes this:
* If The Ventricle Stretches,it will contract with more force
* Due to ↑VR from improved muscle pump

Answer 14

Frank-Starling Mechanism

Question 15

• Circulating Exercise Hormones
  – ie. epinephrine
  means that ________

Answer 15

Increased myocardium contractility

Question 16

Explain the physiology of a myocardial infarction and explain a stress test?

Answer 16

A myocardial infarction leads to heart attacks. This happens due to due to damage/atrophy, blockage in coronary artery (essentially decreased for fully cut off blood flow). An example of a heart attack that can arise from myocardial infarction is ventricular ischemia which is reduced blood flow to the ventricles.

A stress test helps test for potential ventricular ischema by using an EMG to measure PQRST waves. Ventricular ischemia cannot be detected in normal conditions and patient will appear normal on the EMG. However, when under stress ST segment will become depressed.

Question 17

Explain why CO2/O2 exchange only takes place in the capillaries.

Answer 17

CO2 and O2 exchange only takes place in the capillaries for a few main reasons:
- Slow blood flow
- Thin vessel lining
- Capillaries are so narrow so cells have to move in single file

Question 18

Explain four (4) mechanisms we have that ensures adequate venous return.

Answer 18

Venous return: “heart can only pump blood as long as blood can come back to it
1. Valves in Veins
2. Muscle Pump
3. Peripheral Vasoconstriction
4. Respiratory Pump

Question 19

Explain varicose veins and a typical cause for their appearance.

Answer 19

Varicose veins happen when valves in that certain vein aren’t working properly. Veins contain one-way valves that help blood flow upward toward the heart. When these valves become weakened or damaged, blood can flow backward and pool in the veins, causing them to become enlarged and twisted. This pooling of blood increases pressure within the veins, leading to their dilation and the development of varicose veins.

• Exercise is good for varicose veins because of the muscle pump mechanism. In muscle pump when muscles contract valves open naturally creating normal blood flow without any back flow into the vein.

Question 20

Explain 2 main reasons behind a spike in blood pressure during a maximal contraction?

Answer 20

1. Muscle contractions
   - narrows the blood vessels
2. “Valsalva Maneuver”
   - shuts off air:
   The glottis closes, restricting air flow. With huge changes in the respiratory pump and muscle pump the mechanism for EDV have to adjust to rebalance the systems so EDV, preload, and stroke volume increase directly making blood pressure also increase. Eventually if the blocked circulatory or respiratory flow from the isometric movement becomes too much for the mechanisms to control the body will be forced out of the position through fatigue or need to adjust for example taking a breath and losing position.

Question 21

Using an example, explain the cardiac output response of performing exercise in a reclined/horizontal position opposed to in an upright position.

Answer 21

Ex. recumbent bike vs upright bike

HR - decreased in recumbent, increased in standing

SV opposite

B/c venous return is better in sitting/recumbent position. This is important knowledge for example if you were prescribing something for an older client vs an athlete or a beginner vs experienced person in exercise.