Intensity Factor® (IF)* is an indication of how hard or difficult a ride was in relation to your overall fitness. IF® values are calculated by taking your Normalized Power® (NP) and dividing it by your Functional Threshold Power (FTP).
Typical IF® values can range from 0.75 to 1.15 with 0.75 being the easiest and 1.15 being the hardest.
The IF® system compares the energy exerted from one training session to another and lets you check for changes in your FTP. A ride of 1.0 would be equal to your FTP. An IF® value more than 1.05 for a one hour race typically means that a rider's FTP is now higher. Therefore, changes in FTP can be revealed without the need of frequent formal testing.
Here is an example of how this entire system could be used:
Your NP® is 300 Watts. Your FTP is 310 Watts. The IF® for that ride would be 0.97.
If the same ride is performed later in the year and your FTP had risen to 320 Watts, your IF® would be 0.93. This would mean the same workout required you to exert less energy.
The IF® will show on:
If IF® it does not appear as an optional data field, update the software using Garmin Express.
You will find IF® in Garmin Connect on the activity's Details page.
*In order to receive an accurate IF® calculation, you will need to set your accurate FTP in Garmin Connect's power zones. For further details on IF®/FTP, view the Training Peaks website.
Normalized Power® (NP), Intensity Factor® (IF), and Training Stress Score® (TSS) are registered trademarks of Peaksware, LLC.
Garmin Express - https://connect.garmin.com/en-US/start/
Peaksware, LLC - http://trainingpeaks.com/