breathing and heart rate

[plumb]

does not breathing properly cause your heart rate to increase?

[cali-iso]

Breathing and heart rate are connected, but it's a little more complex. From what I understand (bio major), shallow breathing and rapid heartbeat are both a symptom of something else (such as stress, anxiety, excitement), but it's a feedback loop, so once you start doing it it just feeds into the stress/excitement so your heart beats even faster and you breathe even faster. So really the way to decrease heart rate and slow breathing is to try and calm your body, which can be done through taking slow deep breaths. So it's less the breathing causing your heart rate to increase, and more the stress causing your breathing to become fast and heart rate to increase, which then causes your heart to rate to increase even more and your breathing to become more shallow. They feed off each other- does that make sense?
Sorry if that was kind of confusingly written :p