&gt;  so does this mean I am &quot;naturally&quot; fit without really trying?<p>Doesn&#x27;t mean anything. Could even be the case that you have an existing heart condition which causes brachycardia – this is why many doctors will ask for exams if a patient has a heart rate that low. Or could mean that your heart muscle is stronger than what would be expected with your lifestyle. Only a specialized doctor would know.