View this interactive chart on Fortune.com Smartwatches ... it may not be a reflection of your resting heart rate, but an ...

A person’s heart rate may be lower when they are sleeping or higher during exercise. However, some people have an irregular heart rhythm that causes their heart rate to jump between high and low.

Note: The heart rate is different from the heart rhythm, which refers to the thump ... such as: Here is a chart showing how the normal resting heart rate changes with age: In general, a heart ...

This ECG has a narrow QRS complex initally, then a fast heart rate, regular rhythm and no identifiable P wave activity which suddenly turns to a wide complex in a left bundle branch block pattern.

The heart rate increases with inspiration, due to the Bainbridge reflex, and decreases with expiration. The ECG criteria to diagnose sinus arrhythmia is a variation of the P-P interval ...