If you are taking an easy stroll through the mall or around the block, strive to be at 50 to 60 percent of your maximum heart rate. If, however, you are doing a fitness walk, you want your target heart rate to be at 60 to 75 percent of your maximum heart rate. During a high-energy walk, you want your target heart rate to be at 75 to 95 percent of your maximum heart rate.