What causes peripheral resistance?

Answer 1

Peripheral resistance is the force against blood flow. In most cases, an increase in peripheral resistance would be caused by an increase in vasoconstriction, which would decrease blood flow. Other factors can influence vasoconstriction, such as circulating angiotensin II levels, cortisol levels, drugs such as cocaine and other adrenergic agonists, blood volume, atherosclerosis, emboli, renal diseases and increased intra-cranial pressure. An increase in blood pressure will also be caused by vasoconstriction and the mentioned factors.

Answer 2

The heart has to push blood around the body through a network of blood vessels which get smaller as they get further away - towards the peripheral parts and deeper into the tissues of all the body parts. It requires a lot of force to push blood thru all these channels especially small ones. Further, these small arterioles can change size getting narrower and therefore increasing the peripheral resistance that the heart has to push against as it pumps. The control of the size of these vessels is a means by which the body (and drugs) alter peripheral resistance - resulting in a change in blood pressure.

Answer 3

Exercise.

Answer 4

In