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The standard formula for calculating maximum heart rate (MHR) – 220 minus your age – has been used for decades, but a new study found that this math might not be accurate for all women, especially those over the age of 35.
Luckily, the study authors devised a more precise formula for this demographic: 206 – (0.88 x your age)
If you were to apply this formula to a 35-year-old woman, for example, the results would look like this: 206 – (0.88 x 35) = 175.2 MHR
Remember: For optimal fitness, work at 65 to 85 percent of your maximal heart rate during cardio sessions, but always pay attention to your body’s physical cues to determine if you are working too hard – or not hard enough.