Training heart rate has become a confusing concept. There is so much conflicting data on what your exercise heart rate should be, you want to smash your heart rate monitor with that large stack of training guides. It is really not that complicated. Training heart rate will vary depending upon your physical condition and what your fitness or athletic goals are. A trained athlete preparing for an event may exercise at levels as high as 90 to 100 percent of maximum heart rate. That same athlete may have sessions with training heart rate below 60% of maximum heart rate. Individuals with current low fitness levels should exercise at between 50 and 70% of maximum heart rate.