Ramp Test - is 20 Minutes the Magic Number?

I’ve done ramp tests and 4DP tests in the past. Just did the first one today as a newbie to TR. I failed at 20:30. Before the test I didn’t really do any looking at the formulas, and it appears that if I’m understanding it correctly, your old estimated FTP is pretty much around a fail at 20 minutes, or just shy. Am I understanding it correctly? The test today bumped my FTP about a 5% difference.

Not really a big question…just curious if I’ve got the logic in my head. If I’m getting it correctly, seems like it’s a great mental goal to not just hang on at the end, but rather to push anything you’ve got above 20 minutes…to really wring out all ya got!



As above, 19:30 is the “break even” point, but that assumes adherence to the power target.

If you are notably higher or lower than the power target in the 18:30 to 19:30 time range (since the FTP is calculated on the best 1-minute power), you may be above or below the starting FTP value by whatever that power difference is in that minute.


The math also implies that you’ll see a 1% increase in estimated FTP for every additional ~13 seconds that you hang on (at target power). If you have a 250 W FTP going in, this means 1W every 5 or 6 seconds.


good to know!