What Is Power Phase and How Is It Measured?

Power Phase (PP) is a Cycling Dynamic metric which is recorded when using a Rally or Vector dual-sided pedal power meter system. This metric describes where in the pedal stroke a rider starts and stops producing driving forces (power) separately for the left and right leg. Power Phase also indicates where the peak region of work is performed during this phase.

The goal of recording the Power Phase metric is to specifically describe where a cyclist creates power.  You can view power phase metrics displayed graphically on Edge devices and on Garmin Connect.

Power phase is measured as a combination of degrees and arc length, with 0 degrees representing the 12 o’clock position and 180 degrees representing the 6 o’clock position. The length of the power phase is measured by the difference between the starting and end angles. For example, a power phase starting angle of 5 degrees and a power phase end angle of 220 degrees would represent a power phase arc length of 215 degrees. With dual-sensing pedals, this information is provided for both your left and right legs. Then you can view where the majority of power is produced using the peak power phase metric (PPP).