Use a heart rate chart to determine the heart rate that is appropriate for your desired treadmill workout. For example, according to the heart rate chart on DigiFit.com, running at 60 to 70 percent of your maximum heart rate helps build endurance, while running at 70 to 80 percent of your MHR builds stamina.
Use a heart rate chart along with a heart rate monitor to determine the ideal speed and elevation settings. Start by determining your maximum heart rate. A healthy person's MHR is usually around 220, minus the person's age. For example, a 30-year-old woman has an MHR of roughly 190 beats per minute. In general, your target heart rate during exercise should be between 50 and 80 percent of your MHR.
DigiFit allows users to input their age and MHR to view customized charts showing a heart rate goal for each type of exercise. Heart rate levels are divided into five different "zones," each denoting a different level of physical intensity. Zone five is the most intense. Exercising in this zone helps build anaerobic capacity, improving performance for exercises such as sprinting.
To design an interval treadmill workout, determine 70 to 80 percent of your MHR. Spend two minutes at this level, then recover to about 50 percent of your MHR. Repeat five times.