the maximum heart rate is the highest heart rate achieved during maximal exercise one simple method to calculate your predicted maximum heart rate uses this formula 220 your age predicted maximum heart rate example a 40 year old s predicted maximum heart rate is 180 beats minutethere are other formulas that take into account the variations in maximal heart rate with age and gendersually this is when your exercise heart rate pulse is 60 to 80 percent of your maximum heart rate in some cases your health care provider may decrease your target heart rate zone to begin with 50 percent