What is FTP?

Functional Threshold Power is roughly the highest power you can sustain for about an hour. YourIntervals sets every target as a percentage of it, so a 90 % interval means 225 W at an FTP of 250 W.

You can estimate FTP with a short test. The Ramp Test raises power every minute until you can't hold it; the 20-Minute Test asks for one long, even effort.

Both tests are built into YourIntervals: the Ramp Test (free) estimates FTP as 75 % of your best one-minute power, the 20-Minute FTP Test as 95 % of your 20-minute average.

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