Hello. I appreciate you exercise regimen and the fact that you have maintained your health so well even at this age. Athletes do have a slower than normal heart rate. However, If you are experiencing palpitations, which cause you discomfort, it needs investigations. There are certain rhythm disturbances which arise with changes in shape of the chambers or valves of the heart either due to age or with certain medical conditions like diabetes, hypertension, cardiomyopathies or idiopathic i.e. with no known specific cause. These irregularities when identified, can be controlled effectively with medicines. However, sometimes if the irregularities of heart beat remain uncorrected, it may have disastrous complications like a cardiac arrest or a stroke. Hence, I advise you to get basic heart investigations like EKG with long strip, and echocardiogram and a stress test if necessary. If these are relatively normal, you may be attached to a Holter monitor for a day to observe the heart rhythm continuously. Apart from heart issues, other conditions which may give rise to palpitations are thyroid disorders especially hyperthyroidism, anemia or even anxiety. You can rule out these conditions by blood tests or by psychiatric or self evaluation. Hope this helps. Wishing you good health. Regards, Dr Geeta