Functional threshold power or FTP is one of those terms that veteran cyclists and coaches toss around casually, but it can be confusing for newer riders. Once you get a grasp of this commonly-referenced cycling metric, though, you can use it to optimize your training and coaching.

Simply put, FTP is the average number of watts that a rider can sustain in an hour, and acts as a current measure of fitness. Ideally, it refers to a steady effort, not the up-and-down levels you might see looking at your power from a hilly ride or cyclocross race.

FTP, which is typically calculated by a 20-minute test.