Heart Rate And Cardiac Output Essay

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During exercise, the first graph shows the relationship between cardiac output, work, and oxygen uptake. Breaking down the following variables as work increases:

Cardiac Output: (Q= SV*HR) increases with exercise intensities and allows more blood to pass through the body to meet the demand of the muscles’ increased demand for oxygen. Once cardiac output is at its max, it is similar to VO2max and typically plateaus. Since this is a relationship between both hearth rate and stroke volume; the initial increase of cardiac output begins with the increase heart rate, which then, furthers the increase of stroke volume at higher intensities.

Heart Rate: has a directly proportional relationship with work/exercise intensity. As work increases, heart …show more content…

Once a sympathetic stimulation is and/or heart rate increases, stroke volume increases with more force (Frank Starling mechanism) with intensities (depending on body positions) and typically plateaus.

Similarly, with support of the factors of the first graph, oxygen uptake is proportional to its use for oxidative energy. Therefore, increase of O2 use also increases the (a-v)O2 difference. This increase is also known from the rise of carbon dioxide and H+ in the muscles and affects the rise of (a-v)O2 difference, leading to the oxygen unloading in the muscles used in exercise.
This process helps regulate neural adaptions to balance oxygen needs with exercise demands without overusing muscles to breathe.

From breaking down these variables in response to exercise, relationships are proportional to increasing exercise intensity. At rest, heart rate is around 60-80 beats/min. Sympathetic stimulation effects fuel an anticipatory response that cause the heart rate to rise until a maximum heart rate. During max exercise, stroke volume increases in preload and contractility, but decreases in

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