Abstract: A system and method for relating heart rate and power output during exercise includes subjecting an individual to a physical activity that involves maintaining power output at a substantially constant level during a time period while monitoring heart rate. For an initial portion of the time period, there is a generally parallel correlation between power output and heart rate. Subsequently, a separation point occurs at which heart rate increases at a relatively rapid rate while power output remains relatively constant, which provides an accurate indication of the individual's anaerobic threshold. The separation point may be used to determine an exercise regimen for the individual, which may be used in a variety of ways, including in weight loss or maintenance, athletic training, physical therapy, etc. The physical activity may involve operation of an item of exercise equipment, such as a cycling exerciser, which includes means for sensing power output by the individual.