What is the proper heart rate training zone for fat burning versus aerobic exercise?

To find your training zone, find your age at the bottom of the heart rate chart (ages rounded to nearest ten years). The three numbers above your age define your zone: the lowest is for fat burning, the middle for maximum fat burning, and the highest for aerobic exercise. For fat burning, keep your heart rate near the lowest number; for aerobic exercise, keep it near the highest number.