2x20, FTP vs. CTL/TSB

May 3, 17 11:46

Post #1 of 17 (3090 views)

So...I'm getting back into tri after many years off---due to forced medical reasons. I'd only just acquired a LYC PowerTap when I had to give it all up. So, I never got much experience with power training. I'd read one or two articles regarding CTL/ATL/TSB/TSS back then...but, hadn't really made sense of how to use it.

Anyway, I've been back at it since September of last year..and, have been doing FTP intervals since November. I started with 2x10 @169watts, and am currently at 3x17 @210. Anyway, one of the things that is always a struggle is how to normalize a result to previous results. I see a strong correlation between my avg watts and bCTL (R=.85). I see a stronger correlation between Watts/BPM (efficiency factor) and bCTL (R=.89).

But, some weeks just seem to be "off", and others seem to be "ON!!". Eg, last week I did 3x15 @220watts, and felt like I could have done 4x15. This week....I added 2 minutes to each interval (based on feeling strong the week prior). However, I saw a decline in avg watts across each rep (215, 210, 206)...and, it was alls-i-could-do to finish that last one.

My target power for these is 90-95% of my FTP. But, if the effort feels "easy" I'll ramp up a few watts and see how it goes. But if it feels hard, I try and suffer through. I do not look at HR during the effort, just watts and cadence. But, my avg HR for all efforts going back to last year is 155-157, with an average of 156.3 across all efforts.

Generally the "down" weeks correspond with greater -TSB. Continuing with the above example: last week my bTSB was -6 tss...this week, -14 tss. So, I'm curious what those more experienced (and with more data) have seen with respect to good/bad weeks and CTL/TSB or other factors that influence realized performance week over week?

To be clear, I'm pretty happy with the advancement made for the bCTL invested (FTP=182 @ 27bCTL to FTP=220 @ 47 bCTL). I'm just curious any factors others have found that correspond with the occasional OFF weeks.

Last edited by: Tom_hampton: May 3, 17 11:51

Re: 2x20, FTP vs. CTL/TSB [Tom_hampton] [ In reply to ]

May 3, 17 13:11

Post #2 of 17 (2928 views)

Tom_hampton wrote:

Anyway, I've been back at it since September of last year..and, have been doing FTP intervals since November. I started with 2x10 @169watts, and am currently at 3x17 @210. Anyway, one of the things that is always a struggle is how to normalize a result to previous results. I see a strong correlation between my avg watts and bCTL (R=.85). I see a stronger correlation between Watts/BPM (efficiency factor) and bCTL (R=.89).

Many have tried to make that leap but there is no real link between ctl and ftp. When you think about the causation, the is no reason to think so either.

Quote:

But, some weeks just seem to be "off", and others seem to be "ON!!". Eg, last week I did 3x15 @220watts, and felt like I could have done 4x15. This week....I added 2 minutes to each interval (based on feeling strong the week prior). However, I saw a decline in avg watts across each rep (215, 210, 206)...and, it was alls-i-could-do to finish that last one.

My target power for these is 90-95% of my FTP. But, if the effort feels "easy" I'll ramp up a few watts and see how it goes. But if it feels hard, I try and suffer through. I do not look at HR during the effort, just watts and cadence. But, my avg HR for all efforts going back to last year is 155-157, with an average of 156.3 across all efforts.

Generally the "down" weeks correspond with greater -TSB. Continuing with the above example: last week my bTSB was -6 tss...this week, -14 tss. So, I'm curious what those more experienced (and with more data) have seen with respect to good/bad weeks and CTL/TSB or other factors that influence realized performance week over week?

Generally tsb and recent tss trends will connect to how you feel, but it's really hard in tri to document everything perfectly bc rtss doesn't necessarily equal btss.

Re: 2x20, FTP vs. CTL/TSB [Tom_hampton] [ In reply to ]

May 3, 17 14:53

Post #3 of 17 (2817 views)

The charts are extremely helpful in terms of maximizing odds.. not absolutes.

You won't ever find that every time you train at "xyz tsb, or ctl, or atl, or % of FTP" you feel a certain way. Rather, you will start to find that, most of the time you feel good when training at "xyz, etc etc".

All we can hope for is to maximize our odds of success... but there are never any guarantees. You look to be doing all the right things in tracking all of this data so that when you get to race day, you can go in with the best possible odds of success based on your historical data and trends you've noted.

You're basically creating your own bell curve so to speak. Every athletes will differ a touch. Sometimes you'll have an outlier performance, but again... play the odds and go with those trends that you find to be most beneficial to your training and racing.

--------------------------------------------------------------------
COROS Sports Science

Re: 2x20, FTP vs. CTL/TSB [ddalzell] [ In reply to ]

May 4, 17 6:42

Post #4 of 17 (2627 views)

Thanks.

So far my "best" days seem to occur when I'm just slightly negative on bTSB (around -5 TSB) vs. significantly negative (< -10 TSB) or positive. I only have a couple of data points where TSB is >0, but they are all "below the trendline". That said, there is always a reason that TSB is >0 (I have not tapered for anything this year), and that has typically been either illness or a business trip...so, its just as (or more) likely that the poor performances were caused by the illness/week-off.

Re: 2x20, FTP vs. CTL/TSB [Karl.n] [ In reply to ]

May 4, 17 7:33

Post #5 of 17 (2569 views)

Karl.n wrote:

Tom_hampton wrote:

Anyway, I've been back at it since September of last year..and, have been doing FTP intervals since November. I started with 2x10 @169watts, and am currently at 3x17 @210. Anyway, one of the things that is always a struggle is how to normalize a result to previous results. I see a strong correlation between my avg watts and bCTL (R=.85). I see a stronger correlation between Watts/BPM (efficiency factor) and bCTL (R=.89).

Many have tried to make that leap but there is no real link between ctl and ftp. When you think about the causation, the is no reason to think so either.

Hmmm....not implying a causation, but there is a strong correlation, and it is kind of the whole point of Bannister's model (and TSS which is derived from Bannister)...(properly applied) accumulated stress leads to increased performance.

I had a whole period from January to March where my bCTL was pretty flat (23 -> 27). It was more of a swim/run focus period (plus a business trip, and getting the flu). My weekly FTP intervals were equally stagnant at 182 watts...from 11 Jan thru 13 March. From March to now my bCTL has increased from 27 to 47, and my weekly FTP interval watts has increased to 211 avg (with a best effort of 222 last week). My FTP intervals have been 3x15 since 4 Feb, which encompasses the bulk of the stagnant and growth periods. I only switched to 3x17 on Tuesday (as noted it didn't go well...but, that's probably from the total fatigue of the last two weeks).

What changed after 13 March? I changed the character of my Wednesday bike, and my long bike. Prior to 15 March the Wednesday bike was a 90 min Z2 ride, and the long ride was 2.5 hrs in z2. At this time, I changed these to add significant Z3 time. The Wed ride became 45 min in high Z3 (0.9 IF), followed by z2 to fill out the TSS target. And the long ride became 60 minutes at 0.85 IF, followed by enough z2 to round out the TSS target. I've been gradually increasing the Z3 time in each as the weeks progress. Yesterday, I spend 60 minutes at 0.91 IF with a total 102 TSS for the ride.

Could I do it with the same total TSS/ride with all z2 effort? I don't know---I don't have the time to do it that way...so, I add the intensity to gain the added TSS/d instead (hopefully with some level of intelligence).

Re: 2x20, FTP vs. CTL/TSB [Tom_hampton] [ In reply to ]

May 4, 17 7:46

Post #6 of 17 (2542 views)

Your FTP improves when you ride more in the long term and in the shorter term when your TSB is worse, you ride worse.

I guess I don't see what the question is.

Re: 2x20, FTP vs. CTL/TSB [Tom_hampton] [ In reply to ]

May 4, 17 7:58

Post #7 of 17 (2523 views)

I agree that with the above, that your bad weeks don't sound "bad" if your TSB indicated you had a lot of acute training stress. "Bad" is when you have unexplained lack of performance. You seem to have an explained lack of performance.

I think one issue you're having is that you seem to be using FTP intervals as both a workout and a test. If you want to test with more consistency, do it with less frequency (maybe monthly), pick one test protocol (rather than varying interval count and time), and moderate training stress prior to the test.

Re: 2x20, FTP vs. CTL/TSB [Kevin in MD] [ In reply to ]

May 4, 17 7:59

Post #8 of 17 (2522 views)

If that's it, then that's fine. That is the essence of my question. As I noted, I don't have a lot of experience with it...just the last 6 months of data. Basically 18 data points. And this was the first point with an unexpected downward trend.

I was just a bit surprised by the change from last week to this week. Not just the power and inability to hold it across each work interval, but also the RPE...with what seemed like "only" a small difference in tsb (-6 to -14). I guess I'm learning what my legs consider to be significant.

Last edited by: Tom_hampton: May 4, 17 8:02

Re: 2x20, FTP vs. CTL/TSB [trail] [ In reply to ]

May 4, 17 8:19

Post #9 of 17 (2499 views)

trail wrote:

I think one issue you're having is that you seem to be using FTP intervals as both a workout and a test. If you want to test with more consistency, do it with less frequency (maybe monthly), pick one test protocol (rather than varying interval count and time), and moderate training stress prior to the test.

Yes, that's probably true. I don't really look at it as a "test" per se, but more of looking for trends across the sequence. By that I mean, I don't assume my FTP has changed based on any single event...but rather look at the trendline over time. I generally only adjust my FTP after the trend has exceeded the error bars from the current setting, and only then to the value of the "trend".

But, you make a good point...and its one I've been thinking about as I've been planning weeks, recently. Its not the "test" itself so much as the "moderate training stress prior to the test" part of the plan that I end up struggling with. So, I end up trying to keep my weeks relatively consistent (I try not to need recovery weeks) and use the trending approach above.

Re: 2x20, FTP vs. CTL/TSB [Tom_hampton] [ In reply to ]

May 4, 17 8:36

Post #10 of 17 (2480 views)

Higher CTL leading to better performance in the long term and low TSB leading to worse performance in the short term is pretty much the essence of the Banister model. So you are right there.

You are right in that there are things that would throw you off of the prediction, but I don't really see any yet.

Things that can happen:
*You don't recover from every TSS point as well as every other necessarily. Which gets to one of your questions, will I respond to 100 TSS points of easy riding in the same time frame as 100 points of threshold riding? Not exactly no, but within a certain fudge factor yes.

*Work and life stress certainly can affect your performance in testing, and it isn't reflected in the CTL or TSB score.

So it seems like up til now, the CTL and TSB pretty well correspond to what you are seeing.

Re: 2x20, FTP vs. CTL/TSB [Tom_hampton] [ In reply to ]

MergeMultisport

May 4, 17 9:31

Post #11 of 17 (2430 views)

I too like to over complicate things

I wish people would remember 2 things

1) FTP is a measurement taken from ONE day
2) we are NOT machines

These 2 things should lead us to realize that some days we will stronger and others we won't. When you start factoring in sleep, nutrition, hydration status, how heavy has your training been, etc...so many variables.

I wish people would just shut up and train

Side note-yes, I do have a power meter. Yes, I do use it to help measure my efforts. No, I do not solely rely on it to gauge my efforts training and racing.

Merge Multisport Founder & Head Coach
USAT Level 2 - Short & Long Course
Ironman Certified
Brevard, NC

Re: 2x20, FTP vs. CTL/TSB [Tom_hampton] [ In reply to ]

May 4, 17 9:49

Post #12 of 17 (2398 views)

Tom_hampton wrote:

But, you make a good point...and its one I've been thinking about as I've been planning weeks, recently. Its not the "test" itself so much as the "moderate training stress prior to the test" part of the plan that I end up struggling with. So, I end up trying to keep my weeks relatively consistent (I try not to need recovery weeks) and use the trending approach above.

For your trending method, then I'd expand the time scale over which you gauge improvement to months. E.g. over longer time periods even your "off" days will be better than the "off' days 3 months earlier. Don't try to compare this week to last week.

Re: 2x20, FTP vs. CTL/TSB [T.Skelton] [ In reply to ]

May 4, 17 9:56

Post #13 of 17 (2390 views)

T.Skelton wrote:

I wish people would just shut up and train

come on now! I manage to shut-up WHILE training...but, that's only good for 3 hours on Wednesday, 4 hours on Saturday...and 1-2 hours on the other days---the usual 12-14 hours a week. That still leaves a LOT of time for endless data-mining, over-analysis, and useless blather on ST.

Re: 2x20, FTP vs. CTL/TSB [Tom_hampton] [ In reply to ]

MergeMultisport

May 4, 17 11:12

Post #14 of 17 (2332 views)

Tom_hampton wrote:

T.Skelton wrote:

I wish people would just shut up and train

come on now! I manage to shut-up WHILE training...but, that's only good for 3 hours on Wednesday, 4 hours on Saturday...and 1-2 hours on the other days---the usual 12-14 hours a week. That still leaves a LOT of time for endless data-mining, over-analysis, and useless blather on ST.

Touché!!!

I do love when people manage to be get their panties wadded up!

12-14 hours a week? Sounds like somebody needs less ST and more pedaling! ;-)

Merge Multisport Founder & Head Coach
USAT Level 2 - Short & Long Course
Ironman Certified
Brevard, NC

Re: 2x20, FTP vs. CTL/TSB [Tom_hampton] [ In reply to ]

May 4, 17 11:34

Post #15 of 17 (2310 views)

Tom_hampton wrote:

...(properly applied)

...

Could I do it with the same total TSS/ride with all z2 effort? I don't know---I don't have the time to do it that way...so, I add the intensity to gain the added TSS/d instead (hopefully with some level of intelligence).

That's what I'm saying, you probably couldn't. You are properly applying specificity with threshold intervals and seeing a corresponding increase in ftp.

Think about it this way, riding at 300 watts for an hour will yield the same tss as riding at 175 watts for 3 hours. Do they have the same physiological effect?

Re: 2x20, FTP vs. CTL/TSB [T.Skelton] [ In reply to ]

May 4, 17 11:52

Post #16 of 17 (2290 views)

Quote:

12-14 hours a week? Sounds like somebody needs less ST and more pedaling! ;-)

:-) Once upon a time I was young enough to train 20+ a week. Maybe in a year or two I might be able to recover-rinse-repeat like that again...not so much at the moment.

Besides back then I lived 10 miles from the office and was able to bike/run commute, every day---the options were endless for combining the commute with training (bike in, run home, drive back, bike home, etc) while still being able to get home quickly in most circumstances (I could extend either direction to add 20-30 miles...and keep the other direction to a 30min recovery ride, if needed). That job also had showers at the office.

I'm 35 HIGHWAY miles from the current office, and don't have showers available. So, the logistics are much more complicated now (or I have less options for realistically combining commuting with training). But, that's all just whining and complaining---which is not my usual M.O.

Re: 2x20, FTP vs. CTL/TSB [Karl.n] [ In reply to ]

May 4, 17 13:22

Post #17 of 17 (2230 views)

Yes, but...simply doing threshold intervals didn't change my FTP one single watt after I hit 182 and my bCTL was constant. Continuing to increase the training load and the corresponding bCTL increase is what correlates with my FTP change. Its not a weak correlation either. I certainly get the specificity thing...that's part of the reason I chose to add the intensity (the other being time limitations, as discussed above).

Regardless it wasn't really the thing I was intending to ask about. I really only included that data for context. Rather, I was wondering what to look for as proximal causes of a poor performance (other than TSB)...the reason being to make adjustments (whatever those might be) to avoid downward trends in the future. My goal for high intensity intervals (FTP, VO2max, etc) is to meet or exceed the target power and durations. When that doesn't happen I look for what I could have done differently to ensure I hit those targets.

I haven't had any unusual work/life stresses (things are pretty low key ATM), and nutrition/hydration has been very good. Outdoor conditions weren't identical week over week...but, they weren't winter vs. summer, either. My scheduling wasn't "ideal" over the last 14 days due to family conflicts. That caused me to move some workouts around a little. I ended up compacting some bigger days, that I probably shouldn't have done---which resulted in some excess ATL (both bike and run), and thus the greater -TSB in week2. I knew that going into it, I just didn't expect the effect to be as big as it was---now I know. Next time that happens, I'll insert an extra recovery day to ensure I'm properly fresh so I can hit those targets.

All things considered, I'm back on a normal schedule now---so recovery should return to normal over the next week. And I made some solid gains. Maybe I learned something at the same time.

Thanks, all.

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