eli5: How or why does slow deep breathing slow your heart rate?

Question

eli5: How or why does slow deep breathing slow your heart rate?

In: 13

Answer 1

When you slow your breath rate you allow less oxygen in your bloodstream than you would if you were breathing faster so, to compensate this, your body slows pretty much everything down in order to save energy and use less oxygen.
That’s the reason why when we are sleeping our heart rate can go way under the average bpm’s we have during the day.