- originates in the motor cortex or from reflexes initiated in muscle proprioceptors when exercise is anticipated.
- initiates the following changes:
a. Sympathetic outflow to the heart and blood vessels is increased. As a result, heart rate and contractility (stroke volume) are increased, and unstressed volume is decreased.
b. Cardiac output is increased, primarily as a result of the increased heart rate and, to a lesser extent, the increased stroke volume.
c. Venous return is increased as a result of muscular activity. Increased venous return provides more blood for each stroke volume (Frank-Starling relationship, IV D 5).
d. Arteriolar resistance in the skin, splanchnic regions, kidneys, and inactive muscles is increased. Accordingly, blood flow to these organs is decreased.
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Diabetes is a disease that affects the way your body uses food. Normally, your body converts sugars, starches and other foods into a form of sugar called glucose. Your body uses glucose for fuel. The cells receive the glucose through the bloodstream. They then use insulin a hormone made by the pancreas to absorb the glucose, convert it into energy, and either use it or store it for later use. Learn more...