Efficiency Index at Functional Threshold (EI@FT)
Efficiency Index at Functional Threshold (EI @ FT) is your EI when running at your FTP.
In endurance running, training to be more efficient is one of the most effective ways to improve. If you use a running power meter, you have access to a metric called EI, which rates your efficiency. When you run at your Running FTP, your EI can tell you whether or not your efficiency is improving at your FTP intensity, which is an important indicator of your current level of fitness.
Find it in SportTracks
How to test your EI @ FT with SportTracks: Go for a run and try to maintain your current Running FTP. Afterward, when analyzing in SportTracks, you can determine if your EI improved or not by filtering your Workouts page by sport and date, and adding EI to the page by clicking on the gear icon. Compare this run with other identical workouts:
If your EI isn’t improving at your FTP, train to improve your running form and test again.