Cardiovascular Exercise Physiology Flashcards
Layer of the heart that is muscle is the ___________
Myocardium
_______ divides heart into left and right halves
Septum
_______ regulate blood flow between the chambers
Valves
_____ system includes the coronary arteries
Coronary circulation
Coronary arteries branch directly off the ______, supplying blood to the myocardium
aorta
_______ communicates with the heart via Acc. nerve and vagus nerve
medulla
2 nerves parasympathetic and sympathetic are ________ & _________
Accelerator nerve & vagus nerve
RBC’s are removed by the ______
spleen
Measures blood cells over the volume of blood: ______
Hematocrit test
What layer of muscle includes * Vasoconstriction
* Vasodilation:
________
Smooth muscle layer
Pressure exerted by the blood on the walls of the vessels
– Monitored by _________
Baroreceptors
_____ :pressure in arteries when heart contracts
systolic
_______: pressure when heart relaxes
diastolic
What theory/concept includes this:
* If The Ventricle Stretches,it will contract with more force
* Due to ↑VR from improved muscle pump
Frank-Starling Mechanism
- Circulating Exercise Hormones
– ie. epinephrine
means that ________
Increased myocardium contractility
Explain the physiology of a myocardial infarction and explain a stress test?
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.
Explain why CO2/O2 exchange only takes place in the capillaries.
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
Explain four (4) mechanisms we have that ensures adequate venous return.
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
Explain varicose veins and a typical cause for their appearance.
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.
Explain 2 main reasons behind a spike in blood pressure during a maximal contraction?
- Muscle contractions
- narrows the blood vessels - “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.
Using an example, explain the cardiac output response of performing exercise in a reclined/horizontal position opposed to in an upright position.
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.
