Figuring out your target heart rate requires a little bit of math, but it’s worth it once you know the reason why you’re doing it.
Knowing how hard you’re working your body while exercising helps you get the most out of each hour you put into it, challenging your cardiovascular system without overtaxing it.
Comparing your actual heart rate, or number of beats per minute, to your maximum heart rate is a good guide, along with paying attention to what your body is telling you.
This magic number varies with age, and certain medications can affect heart rate. The trick is learning your maximum heart rate, then keeping your heart rate somewhere between the 50th and 85th percentiles of that range.
Maximum heart rates are generally calculated by taking a person’s age and subtracting it from the number 220. You can use this chart as a guide to finding your approximate maximum and target heart rates.
Moderate-intensity physical activity is usually defined as maintaining a heart rate between 50% and 70% of your maximum heart rate, while vigorous activity gets you in the 70% to 85% range.
If you’re new or recently returned to working out, the American Heart Association recommends starting out nearer to the 50% point. After some conditioning you can start pushing yourself forward and eventually reach the point where you can comfortably reach the 85% level.
An activity tracker or monitoring treadmill is the quickest way to know your current heart rate, but you can find it manually by taking your own pulse — press the inside of your wrist, just under your jaw or at the top of your foot. Count the pulses for 15 seconds and multiply by four (or do it for 30 seconds and multiply by two).