The arteries (red) carry oxygen and nutrients away from your heart, to your body's tissues. The veins (blue) take oxygen-poor blood back to the heart.
Increases in peripheral resistance, blood volume, and cardiac output result in higher blood pressure. Conversely decreases in any of these factors lead to lower blood pressure. Three main sources of peripheral resistance: Blood vessel diameter, blood viscosity, and total vessel length.
Cardiovascular Response to Exercise. As muscles begin exercising, the arterioles serving the muscle dilate to provide more blood flow. However, arterial pressure does not decrease because other parts of the cardiovascular system are adjusted to support the increased blood flow to the muscles.
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