Cardiac muscle hypertrophy and cardiac volume increases
Answer the following 3 questions (100-200 words)
1. Explain how regular resistance training that considerable elevates blood pressure during a two-arm curl with 80 lb in the early phase of training can ultimately blunt this blood pressure response as training progresses?
2. Explain the following statement: Task-specific, regular aerobic physical activity not only trains the cardiovascular system, but also “trains” the neuromuscular system, but also “trains” the neuromuscular system to facilitate physiologic adjustments specific to the activity mode.
3. In what way does the Fick equation fully explain the physiologic components that determine VO2max?
Respond to the 3 post below (100-200 words)
1. I really liked the opening question covering cardiac output; “if heart rate decreases at rest and during submaximal exercise and stroke volume increases, what is the net effect on cardiac output (Anderson, J. (2018, May 20)?” In this example, the cardiac output for the most part remains the same and decreases slightly during an endurance training. However, if you are in a maximal exercise then your cardiac output increases.
With all of that being said, “Cardiac output during submaximal exercise does not increase after training, but studies using high-speed treadmills and measurement of cardiac output at maximal heart rates may reveal improvements in maximal oxygen uptake due to increased stroke volumes, as occurs in humans (Evans, D. L. (1985, December)).” Over 3-6 month training period your body will start to adapt to the training.
2. Several changes occur within the cardiovascular system which effect cardiac output as a result from exercise. Cardiac output is the product of stroke volume and heart. Any improvements in these two measures will also improve cardiac output. Some other changes which have a more indirect effect on cardiac output are:
• Arterial and venous blood flow improvements • Cardiac muscle hypertrophy and cardiac volume increases • Decreased blood pressure
After a 3-6 month training program (assuming the program was a mixture of steady state aerobic exercise, resistance exercise and high intensity interval exercise) we would expect to see an increase in cardiac output capacity. This means we can do more work because we have more blood being delivered per minute as compared to before the training period.
3. Cardiac output is the total volume of blood pumped by the left ventricle of the heart per minute. It is the product of heart rate and stroke volume. Cardiac output during submaximal exercise has yielded improvements in maximal oxygen uptake due to increased stroke volumes. Progressively viable redistribution of heart yield to more effective redistribution of cardiac output to muscles by expanded capillarization and increasingly effective oxygen dispersion to cells. This in terms increases oxygen uptake after training. Within 3-6 months if the rate of work increases, the cardiac output increases in a steady manner. This will ultimately increase oxygen demand to max capacity. All in all cardiac output rises during exercise due to increased stroke volume and heart rate.