Maximum heart rate is the fastest that your heart will beat during maximum effort running. There are many formulas for estimating maximum heart rate, this formula is the most accurate (Robergs and Landweher 2002) 206 minus .7 times your age. As an example, using this formula, as a 54-year-old female my predicted Maximum Heart Rate is 168.2 [206 – (.7 x 54)].
The intensity ranges in Table 1 are approximate and caution should be advised as a multitude of factors can impact the reliability of your heart rate and your heart rate monitor. Because each day is different and other variables can influence your heart rate when running, it’s important to remember that sometimes your heart rate can be high even though you feel fine. Variables that can impact your heart rate include
Heat and humidity, hydration, caffeine, alcohol or nicotine, altitude, energy levels, rest, stress and anxiety, medication and medical conditions, hormones, time of day terrain.