For most adults, a typical heart rate will range 60-100. During situations of increased oxygen requirement of the body (e.g. exercise), the heart rate will increase to compensate. This can also occur during anxiety
, pain, or oxygen deprivation. Conversely, increase activity of the parasympathetic nervous system via the vagal nerve can decrease the heart rate. This most commonly occurs during sleep. Additionally, young individuals or those who undergo frequent, vigorous exercise often have pulse rates in the 40-50 range. It is important for you to be evaluated by your physician to determine if this is a normal of abnormal pulse rate for you.
There are several pathologic conditions that can cause an abnormally low pulse. These are commonly due to abnormalities of the heart's intrinsic electrical system. Some such conditions include types of heart block, such as first degree heart block, second degree heart block (Mobitz type I and II), and complete heart block. These are generally uncommon for someone your age. However, some individuals can have congenital complete heart block, which is most commonly associated with mothers suffering from lupus. It is important for you to be evaluated by your physician with a thorough history and physical exam. They may also check an EKG
to determine if this is a normal or abnormal pulse.