Exercise changes the nerve nuclei that regulate the heart in rats Scientists from the University of Bristol have found that moderate aerobic exercise changes the structure of nerve cells that regulate heart function in rats. The changes appeared to be different on both sides of the body, and further research was needed to understand similar processes in humans. The function of the heart is controlled by the autonomic nervous system, which controls vital functions. The stellate ganglia, located in the neck and chest, play a key role in regulating the heart rate. Telegram Max.