Sympathetic nervous system stimulation causes vasoconstriction of most blood vessels, including many of those in the skin, the digestive tract, and the kidneys. This occurs as a result of activation of alpha-1 adrenergic receptors by norepinephrine released by post-ganglionic sympathetic neurons.
Cardiorespiratory fitness assessments include the treadmill stress test which determines your oxygen intake all throughout the test. Spirometry is a test
