Your heart has kept you alive all this time with a nice normal rhythm at an appropriate rate. The structure responsible for such a dependable personal cardiac history is called the sinoatrial (SA) node or sinus node. It can only be defeated if invaded or overpowered. This article has been written to acquaint you with the function of this little node during all of the activities of your life, including your workout, when it protects your organs by supplying you with an appropriate sinus tachycardia.
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