FTP Question

rozzer32

So I did my last ftp test about 5 weeks ago on the turbo. I did my 4th cross race of the season yesterday and I did a pb for 20 min average power which gave me an improved ftp by 5 watts.

Now should I disregard this as it was a cross race and so a lot more on/off then a 20 min effort on my turbo. Or should I use my new ftp. I suppose it's not behond the realms I've improved 5 watts in 5 weeks.

Should I just plan in a ftp test in the next couple of weeks?

viktor

I'd perform an FTP test again see how it compares.

It's also worth keeping in mind that there might be a gap between performance outside and indoors on the turbo.

BrandonA

Were the same power meters used for both tests? Its possible (likely probably) that if you have two then they will be a couple of watts difference in the results they generate.

Also, I find FTP tests quite hard. In order to get the best possible result you need to be fresh and your passing needs to be good. If either are not optimal you will get a lower value. Maybe during the race you got either or both of these nailed better than the FTP test.

rozzer32

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19721692#p19721692]BrandonA[/url] wrote:

Were the same power meters used for both tests? Its possible (likely probably) that if you have two then they will be a couple of watts difference in the results they generate.

Also, I find FTP tests quite hard. In order to get the best possible result you need to be fresh and your passing needs to be good. If either are not optimal you will get a lower value. Maybe during the race you got either or both of these nailed better than the FTP test.

Yes I only have one PM.

I'll schedule in another FTP test on the turbo in the next couple of weeks and see how I get on.

markhewitt1978

It's quite a well known effect that you'll get lower power results on the turbo than you would do outside.

Tom Dean

...or higher

philbar72

my turbo results are consistelntly 3-4% higher than what i can regularly acheive on the road. i'd aim for a test every 4 weeks during your competetive season, and then perhaps every 6 when you are doing base or the equivalent of winter training. seems to work for me.

rozzer32

Yea definitely think I need a retest. Just been looking at my file for the race and my normalised power for the hours race was 30 watts more than my FTP.

okgo

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19721892#p19721892]rozzer32[/url] wrote:

Yea definitely think I need a retest. Just been looking at my file for the race and my normalised power for the hours race was 30 watts more than my FTP.

Personally I wouldn't bother testing all that often, just train and race, its quickly obviously in training and races where your FTP is to within 10 or so watts, you don't need to do these formal tests everyone seems obsessed with. I get that its worth doing something to get a sense of where you're at when you're new to power, but beyond that I don't think I've done one for about 3 years and I know what my FTP is to a useable level of accuracy (I'm sure it doesn't actually matter whether you're 15W off anyway given the broad range of the zones that people follow).

Also, a cross race is likely to have a lot of high bursts of power, and potentially a fair bit of non pedalling time (running?) etc, either way its the type of riding that is likely to give you a high normalised power, one that may well over-inflate where you think your FTP is. I do crit racing at Crystal Palace over summer and I've had NP figures for the 50-60 min race probably 20-30w higher than what I think my FTP is roughly (again, not that worried to the digit), its a lot of surgey efforts and sprints with a lot of freewheeling thrown in.

napoleond

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19721719#p19721719]markhewitt1978[/url] wrote:

It's quite a well known effect that you'll get lower power results on the turbo than you would do outside.

Except for those that get higher power on the turbo... Like me...

For the sake of 5 watts I'd leave it where it is for now and test again in a few weeks.

My last FTP test was my last 25 mile TT a month ago. I don't really bother testing, I just leave Training Peaks to manage it for me.

markhewitt1978

Yes. Strange isn't it! I guess it depends on so many factors, cooling, the trainer itself and your own physiology.

As for FTP I think Strava via Fitness & Freshness makes a decent go as estimating your FTP based on your power output and heart rate just via normal riding.

okgo

It relies on you having done some properly full on efforts though. If you don't it will never know what you're capable of, but my point is that through racing you'll do that at some point most likely. I would think my strava estimate is within 15w of what I think it is, perhaps a touch on the low side as I produce less power in TT position than road and most of my maximal efforts are on TT - and the way strava calculates NP or its version isn't the same.

Actually looking at it, its pretty good, it shows the 15W increase I've generally been seeing on the yearly average from 2014 to 2015.

amaferanga

5W = noise/error.

It'll make so little difference to your training levels that there's no point in worrying about it.

How variable was the 1 hour NP and what was the AP for the hour?

rozzer32

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19722438#p19722438]amaferanga[/url] wrote:

5W = noise/error.

It'll make so little difference to your training levels that there's no point in worrying about it.

How variable was the 1 hour NP and what was the AP for the hour?

My variability index was 1.15.

Average power for the hour was 2 watts below my FTP. NP was 30 watts above my FTP. But some of that will be due to the on/off nature of cross.

okgo

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19722472#p19722472]rozzer32[/url] wrote:

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19722438#p19722438]amaferanga[/url] wrote:

5W = noise/error.

It'll make so little difference to your training levels that there's no point in worrying about it.

How variable was the 1 hour NP and what was the AP for the hour?

My variability index was 1.15.

Average power for the hour was 2 watts below my FTP. NP was 30 watts above my FTP. But some of that will be due to the on/off nature of cross.

I'd just leave as is for now, wait till you have more data. You won't be missing out on much by being a handful of watts out. Last time I bothered to check (I tend to ride to effort vs absolute watts in training) Z3 had a span of 40 or 50 watts, which is obviously more than enough to cover FTP as long as you have a rough idea I reckon.