which division of the nervous system speeds up your heart rate
The parasympathetic branch of the autonomic nervous system (ANS) has nerve fibers that originate in the cranial (top) and sacral (bottom) segments of the spinal cord. The parasympathetic branch calms the body, which is the precise opposite of the sympathetic branch. The parasympathetic system promotes routine activities, such as digesting your food. It slows the heart rate, whereas the sympathetic system speeds it up. It sends blood to the digestive tract, while the sympathetic system sends it to the muscles.