Adjust ftp?

chrisjohnsen

Hi. I recently did a FTP-test, resulting in a FTP of 271 watts. The test was done on a fairly flat road. When going up a hill the other day I did 290 watts for 14 minutes, which according to my ftp would be zone 5. To me this seems like a long (too long?) time in that zone. From what I have read, more than 8 minutes should be hard, if not impossible. So, what I am asking is if I should adjust my ftp a bit up, an if so, what seems reasonable?

Thanks for any thoughts on this.

pblakeney

I thought FTP was what you could sustain, not maximum.
20 minutes IIRC. Someone with more knowledge will be along...

napoleond

Sounds ok to me.
Do another test if you're concerned.

AK_jnr

If you did 290 watts for 20 minutes it would be an FTP of 275 so not sure what you are going on about really. Lol.

w00dster

Hi Chris,
At the end of your 20 minute test you then need to divide your average power by 5% to work out your FTP. So if over 20 minutes you averaged 271 that would give you an FTP of 258.
I think a lot of amateur cyclists have different power levels that we can put out dependent on the terrain / scenarios. For example I know outdoors (especially in a race) that I can put out more than my measured FTP (measured using a power meter not strava). My FTP Tests are done indoors and I really struggle with motivation on the indoor trainer, I'm less comfy on the bike and more fidgety, a lot sweatier etc. Outdoors I can push myself that little bit more.

thomasmorris

FTP isn't a fixed number, it's a notional value for an output you can maintain for relatively long time without blowing up. That relatively long time has no fixed definition so no test can claim to the definitive FTP test.

However, there are several tests which aim to estimate your FTP, so you can set training zones / monitor training stress etc. The accuracy of the test for setting training zones isn't that important, so unless you're making massive improvement it's probably okay to be out by 10-15 watts in that estimate.

The traditional tests are:
- 1 hour maximum, then take that average power as your FTP (still an estimate of FTP though)
- 20 minute max, then take 95% as your FTP (sometimes a 5 minute VO2 max is recommended before).
- 8 minutes tests (not sure on the calculation to get from 8 min max to FTP estimate).
- Tools which take your power curve over all duration and find the point of greatest change in slope etc.

Obviously, the other reason for testing is to measure improvement. So, I'd say pick a test which is most closely related to the event you want to do well in, not the one that gives you the highest FTP estimate. Remember, the FTP estimate is only for setting training zones, so doesn't have to be spot on, however, you'll want to know you're improving over a duration that is closely matched to the racing you do. If you do 25 mile TTs do the hours test, if you do 10 miles TTs do the 20 minutes, if you're a road man / track endurance do the 8 minute.

As for the OPs numbers. If you did a FTP estimate test that gave a result of 271 (assuming the correct weighting was applied) then you'd expect ~285 for 20 minutes, and probably 290-300 for 14 mins. So in conclusion, it looks like the ftp estimate is roughly right (not that getting it spot on to the nearest watt is important anyway).

It's also worth noting that power output can vary a lot with whether you're going up hill, down hill, outside, inside, rough surface / smooth road, headwind / tail wind. Don't let this worry you too much, just try to keep testing consistent so you can measure improvements, the absolute FTP number isn't critical as far as setting training zones are concerned.

Grill

I can do 300w for 20min but only 250w for and hour. Point is, it's a rough guide and shouldn't be treated as gospel.

supermurph09

No I'd leave it, this way you'll accrue more TSS thus have a higher CTL an be able to willy wave on various forums.

Seriously though, you did 290W for 14 minutes, assuming your FTP of 271 was done via a 20 minute test then it's not clear if you would have blown after 15,16 or 17 minutes etc. FTP tests are a guide imo, if you are new to training and are responding well then you'll know when to retest. But if you have been training for quite sometime you'll know within +/- 5W what you can achieve so chances are you'll still be training in the right zones without having to fine tune your FTP.

sloppyschleckonds

AK_jnr wrote:

If you did 290 watts for 20 minutes it would be an FTP of 275 so not sure what you are going on about really. Lol.

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