How does exposing different body parts to cold effect your heart rate?

Answer 1

by exposing the body parts to the cold, you activate peripheral thermoreceptors (which are just little groups of cells in the skin and near the abdominal vessels and viscera that can detect temperature changes). These communicate with the anterior preoptic area of the hypothalamus which then communicated with the posterior hypothalamus. This, then bring about changes in the body to combat the temperature change. Now, exposing to cold will cause a change in blood flow; because one of the main mechanisms of losing heat is through the skin (conduction/convection/radiation into the air). THerefore, the brain will redirect blood away from the skin, and cause the vessels in the skin to constrict, reducing blood flow. WHen you reduce the peripheral blood flow, you increase central blood flow and this causes an increase in central blood pressure. The blood pressure receptors then come in action and detect high BP and respond by decreasing the heart rate in attempting to lowe blood pressure.

Answer 2

Cold Temp. affects the Heart because the heart starts to pump faster to compensate and transfer blood faster to keep the bodies temp. stable.