Hello Dr. Maheshwari, Could you please help me with these two questions. What should my heart rate be when I am resting, and after I have played tennis for an hour? What is the easiest way for me to calculate my heart rate? Thank you, Tasha Age 12   Dear Tasha, Sure....your heart rate should be around 75-85 beats per minute at rest and can increase to 120-150 beats per minute when you play tennis depending on how fit you are (!). You can place your hand on your chest or your pulse on your wrist and count the number of beats in 1 minute and that would be your heart rate. Keep tennising away! Dr Sunita Maheshwari ABP, ABPC (USA) Consultant Pediatric Cardiologist and HOD Narayana Hrudayalaya & RXDX