If you finished the FTP Ramp Test workout from your training plan, and you noted the wattage of the last step completed and the duration of an uncompleted step, you can estimate your Functional Threshold Power (FTP) using the following steps and referring to an example below.
- Step duration: 150 seconds (or 2:30 min)
- Step increment: 25W (given you set your FTP to 200W, as recommended in test protocol)
Example test data (replace it with your numbers):
- Last Step Completed: 250W (or step No. 6)
- Duration of an uncompleted step: 30 seconds
- Calculate your MAP (Maximal Aerobic Power)
- step completion percentage = duration of an uncompleted step / step duration, e.g. 30s / 150s = 0.2
- part uncompleted = step completion percentage * step increment, e.g. 0.2 * 25W = 5W
- MAP = last step completed + part uncompleted, e.g. 250W + 5W = 255W
- Your estimated FTP (Functional Threshold Power) is 82.5% of MAP, e.g. 255W * 0.825 = 210W
FTP Ramp Test workout and all the calculations are based on https://gplama.blogspot.com/2016/07/how-to-do-step-test-on-zwift-pb-hptek.html post.