32/yo.m 318lbs. been exrcsing/eating rite for 2wks now. i know im outta shape bt i feel my heart pound hard when i do cardio after only 5-10min. i take atenolol 50mg of atenolol @ morn & workout @ nite. not sure if its wearing off or palps r serious?

Hold the cardio: for now, and kindly see your doctor/ cardiologist for evaluation, you may need to have a stress test first, or advice on which exercise best suited for your condition, good luck

There is only: one way to determine if the palpitations you have during your workouts are potentially serious and that is a EKG/ECHO monitored Exercise Tolerance Test! Many Cardiologists perform these in their offices. Hope this is helpful! Dr Z