Efficiency Factor

Efficiency Factor (EF) is calculated as Normalized Power divided by Average Heart Rate and represents the number of watts you can produce per heartbeat – higher EF number is better. If you can increase the watts for each beat, you're improving efficiency.

Example: 236W Normalized power / 147 Average Heart Rate = 1.60 EF

How to use the Efficiency Factor (EF)?

The Efficiency Factor is often used in the base training for tracking your aerobic fitness – a productive aerobic base training should result in increased EF over a few weeks.