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What Would You Do - FTP Edition and Bad Data?
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Had a short effort that usually takes me ~40 minutes that my coach had planned for today to see where my fitness was after a serious few blocks. My training has been good and so has my recovery, but during today's effort ended up a few minutes faster at 37:47. My HR was exactly where it would normally be during a serious effort likes this, but I set all time 1, 5, 10, 20 and 37:47 (call it 40) minute power bests. Just using the 20 minute x .95 calculation gives me a number that I've never been able to be within 20 watts of even during peak fitness. I am 1.5 kilos heavier so maybe that actually helped me, but I honestly don't trust my data. My coach thinks he should set my training zones using this data for the next 6 weeks until I have an actual test, but I don't agree.

My power meter is an SRM and has never let me down that I've noticed. It is calibrated and the batteries are fine reportedly, but I also highly doubt this data is right. I've heard of potential stray readings with SRMs that have low batteries. Has anyone else with an SRM seen any data anomalies under any circumstance?
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Re: What Would You Do - FTP Edition and Bad Data? [turdburgler] [ In reply to ]
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Never for me. I guess if i really messed up the zero offset , I could get it to show whacky numbers... but not with a good offset
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Re: What Would You Do - FTP Edition and Bad Data? [dcohen24] [ In reply to ]
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That's what is bugging me. I've never seen weird data. I did my zero offset twice before like I always do so I feel like its good.

I'm just worried that if we set my next 6 weeks based on this and its wrong, I'm going to end up hurting myself again and taking a step back. FWIW, the wind today was calmer than normal so that may have helped the time.

I guess I have a coach so I don't go nuts with this time of stuff. We will see in a few weeks how I respond to the updated training.
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Re: What Would You Do - FTP Edition and Bad Data? [turdburgler] [ In reply to ]
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My coach thinks he should set my training zones using this data for the next 6 weeks until I have an actual test, but I don't agree.
---

So, your coach wants you to step up a level and you're resistant?






Take a short break from ST and read my blog:
http://tri-banter.blogspot.com/
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Re: What Would You Do - FTP Edition and Bad Data? [Tri-Banter] [ In reply to ]
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My coach wants me to step up to and FTP 40 watts higher than I am now. 20 watts higher than I've ever been.

Like I said on my last post I'm going to go with it and see what happens.
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Re: What Would You Do - FTP Edition and Bad Data? [turdburgler] [ In reply to ]
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Could you, I dunno, try again and see if you can get anywhere close?

I'm always flabbergasted when people have no idea where their ftp is. Your training should include regular efforts in the ~.95 ftp range. Try one and see how it feels. If it's doable then you're in good shape, if it's intolerably hard go back to your old ftp values.

Honestly this is one of the drawbacks of all the misinterpreted 80/20 training out there. Those efforts just below threshold are hugely valuable in monitoring fitness.
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Re: What Would You Do - FTP Edition and Bad Data? [Karl.n] [ In reply to ]
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I know exactly what it has been for years upon years and that is why I dont trust this. Literally a decade of data. Not suggesting I dont know my ftp. I live and die with my power.

3 weeks ago I did a 65 minute effort that was 40 watts less than the test of today would suggest I could do for an hour. That is what I dont trust.

I am going to do another effort tomorrow. I'm fried today and already ran after.
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Re: What Would You Do - FTP Edition and Bad Data? [turdburgler] [ In reply to ]
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what's the offset differences (in terms of Hz/Nm) during the interval? when's the last time you checked slope?

the slope could drift, independent of battery condition. I've had it drift 3% on me)

edit 2: if i were in your shoes, i would:

determine if there's any offset drift during your effort, and measure the current slope. If both checks out, or if at least the latter checks out and you don't suspect the former to be off, instead of setting FTP at 40W over current, do 20W over current, and see how you complete those intervals. In the mean time, watch offset like a hawk.
Last edited by: echappist: Mar 17, 19 12:23
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Re: What Would You Do - FTP Edition and Bad Data? [turdburgler] [ In reply to ]
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turdburgler wrote:
I know exactly what it has been for years upon years and that is why I dont trust this. Literally a decade of data. Not suggesting I dont know my ftp. I live and die with my power.

3 weeks ago I did a 65 minute effort that was 40 watts less than the test of today would suggest I could do for an hour. That is what I dont trust.

I am going to do another effort tomorrow. I'm fried today and already ran after.

Fair enough.

To answer your original question about power meters, I've had all types of power meter and read significantly off. Powertap (low battery, 75% low), quarq (got wet, 50% high), SRM (auto offset, 50% low), stages (who knows, it was a stages). So it could be a misread or it could be fitness. Either test the PM or test your legs.
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Re: What Would You Do - FTP Edition and Bad Data? [echappist] [ In reply to ]
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This might be the answer. I've always thought slope is not affected by changing chainrings and that still rings true mostly...except for solid chainrings.

I put an Absolute Black 1x solid chainring on this week yesterday. I will recalibrate and re-test.

Believe be guys, I hope my new FTP is right! The reality is that I've seen how I respond over time and this jump would be very big. I do believe based on all of my training its ~20 watts higher. ~40 watts seems like a reach.

Thanks for the replies.
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Re: What Would You Do - FTP Edition and Bad Data? [turdburgler] [ In reply to ]
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You are now wattburgler. At least now you have a new Internet Watts value.
Last edited by: trail: Mar 17, 19 12:36
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Re: What Would You Do - FTP Edition and Bad Data? [trail] [ In reply to ]
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lol. Unfortunately I think its shite myself! So here we are!

But todays value would adhere with the internets +20 watt rule.
Last edited by: turdburgler: Mar 17, 19 12:39
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Re: What Would You Do - FTP Edition and Bad Data? [turdburgler] [ In reply to ]
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how does your 37:xx power best compare to "watt" your coach wants to set FTP to? should be fairly close
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Re: What Would You Do - FTP Edition and Bad Data? [turdburgler] [ In reply to ]
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What kind of effort was this? It seems really fishy that you would do your best 1min and +30min power bests in the same workout. I wouldn´t use this data for planning training without doing some more tests first.
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Re: What Would You Do - FTP Edition and Bad Data? [turdburgler] [ In reply to ]
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You're not going to hurt yourself, you're just going to be unable to complete the workouts if your FTP is set too high. Then you'll know if it's too high or just right.
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Re: What Would You Do - FTP Edition and Bad Data? [echappist] [ In reply to ]
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Thank you Ecchapist for getting me thinking in the right direction. It was the type of chainring change that necessitated re-calibration and there was a difference. I'm going to re-ride later today and see.
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Re: What Would You Do - FTP Edition and Bad Data? [fb] [ In reply to ]
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It was a rolling TT course that I've used before. There are points where I do get out of the saddle and hammer down to keep speed so seeing high 1 and 5 minute power doesn't really surprise me.
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Re: What Would You Do - FTP Edition and Bad Data? [jaretj] [ In reply to ]
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jaretj wrote:
You're not going to hurt yourself, you're just going to be unable to complete the workouts if your FTP is set too high. Then you'll know if it's too high or just right.

I get that, but I also have a history where I was horrendously overtrained that did hurt me for months. I have a tendency to just stick to the plan and suffer through. Yes if it was too high I would occasionally, but a lot of the workouts I would just be overstretching until I broke.

Going to re-test in a few hours after today's calibration.
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Re: What Would You Do - FTP Edition and Bad Data? [turdburgler] [ In reply to ]
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Seems you should take this advice... I have no idea what my FTP is and why I would even need to know???

https://team.homeoftriathlon.ch/en/teams/home-of-triathlon/blog/triathlon-s-biggest-addiction
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Re: What Would You Do - FTP Edition and Bad Data? [Shambolic] [ In reply to ]
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meh. My concern isn't so much an obsession. Without power I WILL train to hard and compromise performance. With inaccurate power I WILL do the same. I will take my power meter thank you.
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Re: What Would You Do - FTP Edition and Bad Data? [turdburgler] [ In reply to ]
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turdburgler wrote:
Thank you Ecchapist for getting me thinking in the right direction. It was the type of chainring change that necessitated re-calibration and there was a difference. I'm going to re-ride later today and see.

you are welcome, though I was really hoping you could have used the inflated power to good use,say, by opened a few cans of whoop-arse on Zwift ;)
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Re: What Would You Do - FTP Edition and Bad Data? [echappist] [ In reply to ]
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Sadly no watts were burgled in the making of that test. A nice bump, but not what yesterday indicated.

Although on Zwift I'm like 20 kgs with a 980 watt FTP. ;)
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Re: What Would You Do - FTP Edition and Bad Data? [turdburgler] [ In reply to ]
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I suggest bumping it up 50 watts, telling your friends and the internet, come up short on a couple workouts, then quietly bump it back down 10 watts and calling it good.
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Re: What Would You Do - FTP Edition and Bad Data? [Shambolic] [ In reply to ]
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Shambolic wrote:
Seems you should take this advice... I have no idea what my FTP is and why I would even need to know???

https://team.homeoftriathlon.ch/en/teams/home-of-triathlon/blog/triathlon-s-biggest-addiction

Because it represents the highest rate of (metabolically) sustainable power output. It's useful for training as it is for racing.

Endurance coach | Physiotherapist (primary care) | Bikefitter | Swede
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Re: What Would You Do - FTP Edition and Bad Data? [mortysct] [ In reply to ]
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A oval ring like the absolute black will make the powermeter read high. When you say calibrate, you are lugging out a precise weight or are you talking about setting the 0.
Regardless, if your SRM is reading high, ride to those numbers and adjust your ftp +40watt.
If you are keen to keep your oval ring, maybe have it calibrated and the battery replace by SRM (you can do both yourself, I changed a srm battery the other day, 20min solder job (because I was careful) I think you need a a SRM head unit to calibrate it)
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