In blue we have depcted your heart rate. Heart rate is important because the heart's function is so important. The heart circulates oxygen and nutrient-rich blood throughout the body. When it's not working properly, just about everything is affected. Heart rate is central to this process because the function of the heart (called "cardiac output") is directly related to heart rate and stroke volume (the amount of blood pumped out with each beat).

A normal heart rate is usually stated as 60 to 100 beats per minute. Slower than 60 is bradycardia ("slow heart"); faster than 100 is tachycardia ("fast heart"). But some experts believe that an ideal resting heart rate is closer to 50 to 70. Regardless of what is considered normal, it's important to recognize that a healthy heart rate will vary depending on the situation.