Your Maximum Heart Rate is generally determined by your age (220 minus your age). This is not a random number based on your fitness as you get older, but is based on the heart’s ability to contract due to its aging muscle fibers (among other things). I used to think that if I tried hard enough, I could achieve the same Maximum Heart Rate as I did when I was 20. This is not possible! Unfortunately, as we age our hearts do have maximum upper limits.
What do we use the Maximum Heart Rate for? Using your age, you can determine your Maximum Heart Rate and then your Target Heart Rate based on your conditioning goals. Target heart rate during moderate intensity activities is about 50-70% of maximum heart rate, while during vigorous physical activity it’s about 70-85% of maximum. As an example, if you are walking for fitness (as compared to a leisurely walk), you should try to get your heart rate up to the 50-70% range. But if you are jogging or running, you should target 70-85% of your Maximum Heart Rate
This table shows both the maximum and target heart rate zones for different ages. In the age category closest to yours, read across to find your target heart rates. The figures are averages, so use them as a general guide.