This number is an estimate of how fast your heart is capable of beating. The goal of a complete cardiovascular workout is to aim to be within your target heart rate zone, which is typically 50 to 70 percent of your maximum heart rate.

At the beginning of a new exercise regimen, aim for the lower end of the target heart rate zone and gradually ramp up to the higher end. For example, a 30-year-old male just beginning a fitness routine should aim for a heart rate close to 95 and should work up to a heart rate around 133. Achieving a heart rate within this zone has been shown to help decrease body fat, blood pressure and cholesterol, all with a relatively low risk of injury.

The "talk test" can help gauge if you are exceeding the target zone. If you are at the lower end of your target zone, around 50 percent of your maximum heart rate, to you should be able to talk easily while exercising but still feel like you are exuding a good effort into your workout. At the upper end of your zone, closer to 70 percent of your maximum heart rate, it will become difficult to carry on a conversation during exercise. This is simply a guide and not a substitute for being aware of what your body tells you throughout any exercise program.

The more conditioned your heart becomes, the more challenging it is to elevate your heart rate. The healthy heart rate zone is adjustable, depending on the level of fitness desired. For more intense fat-burning, endurance and performance workouts, the scale will shift approximately 10 percentage points, respectively. It is recommended that you only work toward these goals under the guidance of a physician or certified trainer.

A treadmill stress test is another accurate method of determining your heart health and should be considered for those who are overweight, have a history of heart disease or are over age 35.