I have been diagnosed as sinus tachycardia in ecg but no cases is found in echo, I mean echo is normal. For this I am taking metoprolol succinate xr 25 mg. After taking few days, my resting heart beat rate is 70 to 75 normally. Two days ago I have done light exercise like jumping. On morning I have pain in leg area. That may be due to muscle spasm as I think. On that day my resting heart rate is above 90. Is increase heart rate related to that pain or what might be causing the problem.