Page 1 of 1

Strange power numbers for LT test

Posted: Fri Feb 05, 2010 7:58 pm
by peter foster
I have been getting some confusing data while attempting to do LT tests on the bike the past couple of weeks.

Last year my LT power was in the 205-220 Watts range and the corresponding HR was 148-152. Speed was in the 20-21 mph range. I am 51 years old and a back of the pack triathlete.

I got on my bike around new year to start the seasons training and I can't get either my power or HR up at all.

Typically I cannot go over 135 for HR and power is around 120. Speed is around 19mph. My legs just won't deliver any more.

My running and swimming are tracking as per previous years. LTHR for running is 150.

I suspect I am doing the bike tests while still tired from running the day before, or am I just plain unfit? Can I lose that much power in a few months? I rode through October last year, then focused on running. I have checked the set up for the power meter and the parameters seem OK. Coast downs worked OK and the 4 mile ride. It has been very cold and windy here in Texas, might that upset the ibike?

Todays file attached, plus a race file from last summer

Any ideas appreciated.

Re: Strange power numbers for LT test

Posted: Sat Feb 06, 2010 4:06 pm
by bex
Hi there
I am sure there will be other, better answers for you but I thought I would chip in. I just did a community coaching course for triathlon and want to get some more Ibike knowledge under my belt.
Am I on the right track?
What does your perceived effort feel like?
What is interesting is that you would usually expect HR to be high if you were over-trained or too tired from previous work outs (wouldn't you?)
How about your breathing? Hard for the effort or not so bad?
Hopefully, Coach Boyd will offer up some sage advice for you.
Did you change your position on the bike, maybe you changed something off season and lost power as a result?
Now that I have looked at the test in IB software:
Looking at the ride file, I would say the route for the test was perhaps not conducive to a LT test, I could be wrong though. Cadence drops off a little too often maybe? Try to keep your cadence in the mid 80's through the ride, I believe that is best suited to triathletes (except Chrissie Wellington....., shes a monster:-)
I wonder if your Crr is correct? Ride file is .0001 and profile is .0058 not really sure what that means or if its significant.
And there was a tail wind in the last three miles as well as the majority of the first portion of the ride, was it an out and back?. Average wind was -4.6 So I would say that explains the low heart rate.
Not sure any of this is going to be any use to you, I would appreciate some critique from the experts on the forum.
So, in a nutshell, do the test again is my suggestion, nothing wrong with you, just find a better route.

Cheers for now

Bex

Re: Strange power numbers for LT test

Posted: Sat Feb 06, 2010 5:58 pm
by peter foster
Good points.
Yes I have a slightly new set up: new saddle, dropped seat height down about 1 cm and back about 1 cm. Its more comfortable. Got a fit done at the bike store. Perceived effort was about 7 or 8 out of ten. The route snaked into and with a strong wind. Not out and back. I was chasing watts with the tail wind, but doing up to 26 mph.
I am going to do another set of coast downs tomorrow and then re-test.

Re: Strange power numbers for LT test

Posted: Sat Feb 06, 2010 6:24 pm
by bex
It would be interesting to put your seat back to where it was and then run the test again, same route and compare.
Ensure you mark/note where the seat was before you do (bin there done that)
The trade off for comfort can sometimes be power, thats the reason I make the suggestion.
Please keep us updated. Not too many triathletes on here I think, it all helps.

Bex

Re: Strange power numbers for LT test

Posted: Sun Feb 07, 2010 10:54 am
by coachboyd
Your crr number was a negative in both files which is not good. I took the liberty of creating a profile for you (I also noticed you still have a Gen 2, moving to a Gen 3 will help with having to get the tilt perfect before every ride).

I can definitely see better fitness in the file from last year. Under similar conditions, you were fairly quicker last year. . .and the watts show. If you apply this profile to both files, all the data looks good.

You can use this profile for now. Save it to your computer and then open the iBike software. Go to profiles->edit profiles->import. Then you can select this file and send to iBike. This should give you much better results (although the tilt correction in the Gen 3 really makes a big improvement on the road).

Re: Strange power numbers for LT test

Posted: Sun Feb 07, 2010 5:21 pm
by peter foster
Thanks for the input and the file. I will tell you how it goes in a few days.

Re: Strange power numbers for LT test

Posted: Thu Feb 11, 2010 10:01 pm
by Morocco Mole
bex wrote: What is interesting is that you would usually expect HR to be high if you were over-trained or too tired from previous work outs (wouldn't you?)
Bex
Actually you will normally find that when over trained or tired you HR will be lower. Sometimes you muscles are not fully recovered from a previous workout, and you simply do not have the energy to elevate your HR to usual levels. Note, I'm talking about Threshold or Sub-maximal HR while you are exercising, not your resting HR which some studies have shown to be elevated when over trained.

Re: Strange power numbers for LT test

Posted: Thu Feb 11, 2010 11:32 pm
by Ratman
Morocco Mole wrote:
bex wrote: What is interesting is that you would usually expect HR to be high if you were over-trained or too tired from previous work outs (wouldn't you?)
Bex
Actually you will normally find that when over trained or tired you HR will be lower. Sometimes you muscles are not fully recovered from a previous workout, and you simply do not have the energy to elevate your HR to usual levels. Note, I'm talking about Threshold or Sub-maximal HR while you are exercising, not your resting HR which some studies have shown to be elevated when over trained.
Morocco,

I'm interested in heart rate response to exercise. I've always seen mention of elevated heart rates produced from fatigue, although the most memorable instances were to morning resting pulse rates (upon first awakening from sleep). Do you have a reference from a peer-reviewed scientific journal article that has reported a depression of threshold and/or submax exercising heart rate attributable to overtraining/fatigue?

Thanks!

Re: Strange power numbers for LT test

Posted: Fri Feb 12, 2010 7:45 am
by bex
Certainly my comment was based purely on anecdotal situations, myself included.
What I have found/noted was certainly the case following a series of hard run or bike sessions where intensity was higher than it was supposed to have been (the more is better syndrome:-) thus causing the over training.
Then, when it came to doing an easy spin or run, heart rate could not be kept down, but breathing was easy, as expected for the session.
Because of this, I now try to always wear a heart rate monitor for running and of course have the Ibike for cycling.
Perceived effort is not enough and can let you down, in my opinion.

Bex

Re: Strange power numbers for LT test

Posted: Sun Feb 14, 2010 10:13 pm
by Morocco Mole
Ratman wrote:
Morocco,

I'm interested in heart rate response to exercise. I've always seen mention of elevated heart rates produced from fatigue, although the most memorable instances were to morning resting pulse rates (upon first awakening from sleep). Do you have a reference from a peer-reviewed scientific journal article that has reported a depression of threshold and/or submax exercising heart rate attributable to overtraining/fatigue?

Thanks!
Here is one article I quickly found, all the various references are listed at the document footer. http://www.powerbar.com/articles/49/Ove ... falls.aspx

Specifically:

(3) Baumert M, Brechtel L, Lock J, Hermsdorf M, Wolff R, Baier V, Voss A. Heart rate variability, blood pressure variability, and baroreflex sensitivity in over trained athletes. Clin J Sport Med. 2006 Sep;16(5):412-7.

I'm sure my recollection of this was from either Friels books or articles on his blog. Certainly mirrors my own personal experiences that when fatigued or over reaching I am unable to elevate my Threshold HR to normal levels.

P.S another reference

http://journals.lww.com/acsm-msse/Abstr ... e,.17.aspx

Re: Strange power numbers for LT test

Posted: Sun Feb 14, 2010 11:47 pm
by Ratman
Thanks, Morocco -- I appreciate the effort digging those references up and look forward to reading the articles (I work as a Personal Trainer, so I'm "in the business." :)

Re: Strange power numbers for LT test

Posted: Mon Feb 15, 2010 2:50 pm
by peter foster
Ok, Managed to do a new set of coast downs and recalibrate the ibike computer.
I did an out and back of 6 miles where I started to see familiar HR and power numbers, getting up in the 140's for HR and pushing through the 200's in power.
The HR readout was a little erratic, I might not have been getting good contact or the battery is low ( haven't changed it in at least 2 years). Got new baterries today.
Waiting on some decent weather to re-dothe LT HR test. But feeling much better about what is going on.
6 mile calibration ride file attached.