Dr. Myerburg answers the question: 'How Do Pacemakers Know To Pace Faster?' — -- Question: How do pacemakers know when I need a faster heart rate, for example when I am exercising or anxious?

Understanding your heart rate is crucial for more than just reaching optimal fitness–it can also help to reduce injury and stress, and even predict illness ...

You can also test the accuracy of your numbers out on the run, for example by running at what feels like a hard pace (using the ‘talk test’, you should only be able to get two or three words out at a ...