1 doctor weighed in:
Why does my heart beat speed up and slow down?
1 doctor weighed in

Dr. Cory Annis
Internal Medicine & Pediatrics
In brief: It depends
Heart rate varies naturally with your breath.
In some folks, it's really obvious & called "sinus arrhythmia" which is not harmful. With that, your pulse consistently slows when you breathe in and speeds up when you breath out. However, there is such a thing as "too fast" usually over 100 at rest, and "too slow", usually under 50 at rest. See your md if you are not sure.

In brief: It depends
Heart rate varies naturally with your breath.
In some folks, it's really obvious & called "sinus arrhythmia" which is not harmful. With that, your pulse consistently slows when you breathe in and speeds up when you breath out. However, there is such a thing as "too fast" usually over 100 at rest, and "too slow", usually under 50 at rest. See your md if you are not sure.
Dr. Cory Annis
Dr. Cory Annis
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