FTP test: effect of wind on validity? Other feedback?

I'm a proponent for doing tests on the trainer, but if you're going to do it outside, I think the riding into the wind or uphill for the 20 minute test is a good thing.  You're testing for power, not speed, so ensuring that you have constant resistance is key.  A downhill route or one with dips on the road will result in periods of either coasting or less force being applied to your pedals. 

Solid ride!  I love using Power to train, but make sure you remember to head out and ignore the wattage once and a while!

Wind doesn't effect power unless you are effected with really strong wind that makes you unable to push watts with tail wind. Did you do out and back for 20' and which way was the wind compared to riding. One thing with wind if it moves or gusts it can be hard to keep power steady and your vi will be higher.

I used to do the Coggan method of testing but find the CP doing a long and short test to be more accurate. The 95% of the 20' test I find over estimates FTP. Once your zones are set with all the riding you do you can feel if the zones feel right or not. I can almost always tell when my FTP has gone up (or down after injury or time off) as zones don't match up with RPE.

I use trainer testing for trainer rides. I find after winter of riding on the CT, once I get outside and ride for about 6 weeks my FTP normally goes up 10-15% usually 12-13%. If I used trainer testing for outdoor zones, my zones would be to low.

Enjoy training with power John. If you like numbers you will find it fun.

kathy, the wind was solid in my face or off my shoulder the whole way, no tailwind on the testing segment. I tried to keep power steady, at most I would click down a gear on the crosswind stretches and back up one in the headwind. I think for a first test I was fairly constant. started a little too strong, power ebbed a little in mid-test, fell from about 252 watts average at 10 minutes in to about 243 at the 17-minute mark but then made a concerted effort over the last three minutes and got it back up a little. Was fairly spent after that.

Yeah seems like a lot of people test on the trainer, but I can tell you the next 90-minute effort i do indoors will be my first. Might even be my first over an hour (see my "took the winter off" comment). I'm going to do my training outdoors i just as soon do the testing outdoors.

From my limited eperience, I completely agree with Fred:

* I test indoors for indoor training, outdoors for outdoor training.

* Testing into the wind, or up a hill, is a good thing.

Average power and xPower are pretty close -- I'd say it looks like a pretty good test.

You may have been typing as i posted previously, but the tailoff was more just after the midpoint, probably more to lack of focus and uncertainty about completion. Last three minutes were on a section without turns straight into the wind and i pushed with all i had left.

Good test.

Agree with others that wind shouldn't affect your test as long as it's fairly consistant.  If it's gusting then becomes still off and on, then your power numbers will jump all over the place which makes testing more difficult...but doesn't necessarily prove the test "invalid".

I agree.  Unfortunately, I have yet to find a good place to do a good test outdoors.  Finding an open road without intersections and/or rolling hills is a very hard thing to do!  I compensate by putting a lot of effort into ensuring my trainer test is as optimal as possible; kick the A/C down to ~60, 2 large fans, music to pump me up, etc..  I've found my indoor results results to be fairly accurate both indoor and outdoor. 

Looking at your vi per wko+ is key to seeing how steady you are.  VI is ratio of NP/average power. If you are over about 1.03 your test execution could be better. First few times testing there is a learning curve to how to execute well.

My last tests I started out to easy and my power went up throughout both my 3' and 20' test which means execution was off. I hadn't been doing Z4 or Z5 intervals much so my feel was off a bit. You can tell by looking at your graph. Sounds like end of middle your focus fell off a bit and you were able to pick it up at the end well.

Very solid work and I'll look forward to see how your FTP changes over the season.

Your FTP can vary day to day and how much fatigue you are carrying and other factors make a difference. Some coaches have folks test at the end of recovery weeks which makes FTP as high as possible. Other coaches test during normal training week so fatigue is similar to normal rides.

Where/how would I find that on Golden Cheetah (or Garmin Connect)?

Awesome...yeah, so you can smooth that out a bit on golden cheetah, but overall you can kind of tell that there are some bumps in the middle of your time trial.  That curve should be as smooth as you can make it.  The little hills affect it here and there also.  I think it's just tough to maintain a constant power and focus on pushing that hard, while trying not to get killed by a car or something.  I did the one below inside as my first indoor time trial.  Obviously I couldn't keep it that constant either.

(Power test.jpg)

That is valid test, results are solid. You executed it correct. It is typical to see the fade at the moment where you had it, first few times. With further testing you will learn to even it out.

Your numbers look valid. 

It is always easier to achieve higher watts into the wind and uphill than opposite. If the combination of gearing, wind and cadence is optimum for you, more likely you will put higher numbers than on an out and back, ie. upwind/downwind. There is a metabolic cost issue if the combination of above is putting you at sub optimum cadence for you for the test time, you are bound to fade faster into the wind, only if that is the case. If your gearing and wind fell together to allow for your optimum, than you are golden.

Test method chosen. Stick with what ever you chose and don't change for the sake of consistency. All of them are good. The above mentioned Monod CP 3min/20min test had me overestimating my FTP entire last year, so methods can be individual. I switched to EN 2x20min(2min) and it seems to be more accurate in my case. No need for you to change.

Software. GC and Race Day have the same author. You do notice your xP being consistently lower than AP, that is not the way it should be, unless you had significant periods of no pedaling during the test. That is what torques me about the software. I have been a Race Day user for over a year now, I found that part unsat. Same counts for GC. Your normalized power during efforts will always be higher than average power unless, as stated above. Even on the trainer this thing displays xP lower than AP. You are going to have to decide how are you going to use the AP vs. xP with GC, I take it with great reservation.  

 I test on a flat loop course to get exposure to wind in all quadrants. Those are hard to find, but I have an airport 30min away and I loop there. Keep the test site consistent also, even if it not perfect, it will be consistent.

On the final note, always document temp and humidity. They will greatly affect power generation and metabolic cost of what you are producing. Much like running pace, power begins to drop off with rise in heat or humidity but at a lesser rate than run pace as the cooling effect on the bike mitigates some of it.

Testing on the trainer is a valid alternative, however unless you are cooling yourself well, those numbers will not come close to your outdoors watts.