Now can I change my values ?

giannip

I know I've asked before and on advice from others, I have waited untill a few more races were nder my belt.

latest race stats:

Peak 60min 283NP

Peak 20min 312NP

While I know this is not exactly a 60 or 20min TT I think now I may have enough proof that my ftp is no longer 250.

I think it's time to change...not ?

daveryanwyoming

NO, YOU MAY NOT CHANGE YOUR FTP ESTIMATES

Seriously it sounds like you're due for an FTP bump. Have you looked at the histogram for say the last two to three weeks to see if you have a noticeable step down? How about your long L4 intervals, do they support the new higher number? I rarely go full out during 20 minute L4 repeats, but find I consistently ride them within 10 to 15 watts of my current FTP based on race NP and histogram step down. How about your longer L3 and SST intervals. I know my FTP has increased when I can suddenly do hour or longer uninterrupted L3 intervals comfortably at a power output I had been calling L4. If you've really increased your FTP to 283 or above you should have no problem holding 250 for a really long time.

It sounds like 250 is no longer accurate, but there should be a lot more evidence than the single race if you go looking for it.

-Dave

giannip

No this isn't a decision after one race. It's been quite a while now I have noticed a change and over the last weeks (4 weeks at least) "felt" that 270 was around the new mark.


Yesterday's race took us up a climb of around 10min and that's where my 20min power values kicked in on the graph. The climb felt hard but I was able to stay in the group without thinking would be dropped.

I'm definitely maintaining higher values than before so I'm sure it's time to change. There is a 40km TT coming up on Tuesday which I could use as a test but not sure if I'm mentally up to it after Sunday.......maybe I'm just being lazy....

Ergoman

Why don't you just ride a 20 min test and find out for sure?

rmur17

possibly 'cause 20-minutes sustainable power ain't FTP

__________________
rmur

Ergoman

Educate yourself. See page 50 "Training and Racing with a Power Meter". I refer to this 20 minute test.

rmur17

wow I'm ashamed of myself .... duly noted sir Egoman ...

__________________
rmur

giannip

Because as it's the racing season;


a) I don't feel as motivated to do a 20min test

I would prefer to try and stay mentally fresh for the Sat / Sunday races.

We alos have mid-week (1hour) races coming up so I don't want to overdo things.

Not sure if a 20min test would cause me to overdo thing....but mainly it's the motivational thing.

daveryanwyoming

You might want to bone up on FTP estimates as well. For instance the coauthor of that very same book who happens to hold a doctorate in exercise physiology doesn't consider the 20 minute test to be a very accurate FTP predictor. Once again here's a link to Andy's 7 deadly sins piece on best ways to estimate FTP. Notice the 20 minute x 0.95 approach doesn't make the list?

http://lists.topica.com/lists/watta...l?mid=910290920


Read up on Monod-Scherrer CP curves and you'll understand why a swag like 0.95*20 minute power just can't work across the board. On another forum Andy gave a great example comparing his 20 minute to FTP relationship (~0.98 during general endurance training, dropping a bit when he focused on pursuit training) and his wife (0.92 with her very high AWC). That's a pretty wide variation in terms of estimating FTP from 20 minute power. For someone in the OPs power range that's roughly a 20 watt difference depending on his personal AWC to CP relationship.

Given where rmur checks in on the FTP poll (380 watts, ~4.5 w/kg and that was a while ago) I bet he understands a thing or two about FTP estimation

-Dave

Ergoman

It's really amusing how all the experts come out of the woodwork when it comes to power and FTP. It's even more interesting how the experts disagree with each other and with themselves. Dr. Coggan apparently disavows more that's written in his book than he agrees with. What's a simple bike racer to believe? Bottom line: The 20 minute test is simple and quick and will definitely shed more light on the OP's FTP than all the analysis and discussion posted here.

BTW. Having a high FTP does not necessarily confer any knowledge or understanding of FTP. It may just indicate a power meter out of calibration.

daveryanwyoming

Good point, the guy who coined the term FTP, developed the NP and TSS algorithms couldn't possibly understand accurate vs. inaccurate ways to estimate FTP. On the other hand you read a book so the 20 minute approach must be better........

BTW the recommendations given above such as histogram step down for recent rides and sustainable long interval power are both faster and easier since they rely on data already collected. Andy also suggests both as well as NP from a hard one hour race (the OPs starting point) as more accurate than 20 minutes x 0.95 . He's not making it hard to know what to believe, he's freely posting these recommendations on forums like this one. The info is there if you go looking for it and I wouldn't be rubbing your nose in it if you hadn't gone there first with your arrogant comment towards rmur who beyond his power numbers has consistently demonstrated his knowledge of the subject and his willingness to help others. Just surf through the last two and a half years of his posts if you're not convinced.

giannip

Thanks everyone. To be honest I'm not sure that doign a 1hr TT or even a 20min TT is going to push me like riding the race I did on Sunday as it's probably the second hardest course of the year.

Even if the figures are slighly lower (surely not by much) than what I would do on my own, that to my mind isn't a bad thing. I'd rather not overdo things by training right on the edge.

Does this make any sense ?

rmur17

I'd suggest to keep the 1.05 factor in mind when it comes to NP (60min) versus FTP. The majority of the data (Dr. Coggan's that I've read about) indicates an 'error band' of about 5% at the hour mark.

When I set a new NP for an hour duration or thereabouts, I look at a few things:
1. What was the AP for that time frame? What's VI or simply NP/AP for that period?
2. What's FTP currently set at? What's the differential between NP(60) and that FTP? Or what's the potential increase?
3. What are my recent L4 workouts telling me about FTP?

One case is simple:
1. AP > FTP and NP ~ AP -> set new FTP based only on AP. Gold standard FTP.

Others less so:

2. AP > FTP, NP > AP and VI is typical -> I would set new FTP based on average of {AP, NP}. This is a fairly conservative approach.

3. AP < FTP, NP > AP and VI is typical -> consider recent L4 workouts before increasing FTP.

4. AP << FTP, NP > AP and VI is high -> re-test before changing FTP unless recent L4 workouts have been very strong.

There are other combo's but in general I'd suggest keeping that 1.05 rule in mind, not taking NP blindly especially in high VI cases, and keeping recent L4 workouts in mind. For me, recent L4 work is the simplest tell on where FTP is heading. When I'm struggling, FTP is stagnating or dropping. When they're going well, FTP is very likely on the rise and a race opportunity simply confirms that.

FWIW, I don't believe any of the commonly available commercial PM's are THAT accurate yet so I always round FTP to the nearest 5W. Whether it's 299, 300, or 301 in reality, 300W is plenty close enough.

All the foregoing assumes a properly calibrated and zeroed PM of course. Nothing worse than a super performance turning out to be an artefact.

hopefully that's of some help,

__________________
rmur

acoggan

The best predictor of performance is performance itself.



Not to mention physiological (e.g., day-to-day) variability.

I wonder if WKO+ should be reconfigured to only allow changes in functional threshold power in 5 W increments?

Last note: As far as I am concerned, Rick Murphy is certified in power-based training, and when he speaks, everyone should listen.