What happened to the DUMB workouts? Two that I do regularly this time of year have changed DRAMATICALLY! Both Take Me to Church - 180 and Lucy in the Sky with Diamonds - 180 have raised the power on the major blocks by 14% in the ZWO workout files!
I simply cannot complete LITSWD - 180 at 14% higher than last year and doubt very many can. This is using the same FTP setting in Zwift despite Xert (erroneously) claiming my Threshold Power is some 17% higher than last year at this time. What is going on with Xert???
Hi Brian, they haven’t changed at all. ZWO format requires all intervals to be defined by %FTP. Xert defines many workout intervals by your entire fitness signature (e.g. XSSR, Target MPA, 5 min power, LTP, etc.) If your signature has changed dramatically since you originally exported the workout, then it may need to be re-exported. I’d start by doing that first.
I keep copies of every workout I do. The versions I did last year are about 14% lower %FTP than the ones shown today. How much would my fitness signature have to change to cause such a HUGE change in workouts that are described as “long slow distance” and “pure endurance?” The intervals in Lucy 180 went from from 71% to 94% FTP and Church 180 went from 71% to 85% on the 12 minute intervals!
Regarding my fitness signature though - perhaps that is the problem. At the very least, it seems to be a problem. There have been 3 distinct steps up in my Threshold Power as reported by Xert since September 2023. That’s the number I use for my Zwift FTP setting. I see there have also been 3 even larger steps up in Low Threshold Power (which I don’t use for anything, but perhaps is more relevant here?).
After the first step, I thought I was actually making progress but started to get suspicious after the second. The 3rd seemed very fishy. I wasn’t doing any formal workouts during this time and I saw all the talk about “updates” so I ignored it. Then I got back on Zwift for indoor workouts and quickly discovered something was very wrong.
I found one ride with obvious bad data that I flagged. Do I need to manually force an update of my Fitness Signature?
Exporting a Xert workout to ZWO (instead of using EBC) creates a snapshot workout reflecting your fitness signature at time of export. All of the intervals whether TP based or otherwise (XSSR, MPA, LTP, dynamic, MMP, etc.) are keyed to your signature values as of that moment in time. A ZWO export converts Xert intervals to watts and duration targets.
IOW don’t save workouts in ZWO format to use in the future. Correct strain targets won’t apply. Instead export a workout as needed.
Your signature is constantly in flux. ANY activity with power recorded affects your signature regardless of the source or type and regardless of whether a BT is detected. That includes indoor, outdoor, workouts, free rides, or virtual activities.
A lack of activity also affects your signature due to decay.
To view historical changes in your signature, select Activities, Table and sort by date descending.
If you suspect your signature is incorrect first compare your PP/HIE relationship to this bell curve chart.
You can also view the Activity table, add Max Power as a column, and sort by that column. Flag any entries with obvious power discrepancies.
To manually adjust a signature view last activity (or last BT activity), adjust values below chart, and select Save/(Lock). Any adjustments moving forward will be applied to those numbers. And any ZWO exports will use the adjusted signature values moving forward.
Yes, I understand that. I download (and archive) the ZWO file for every workout I do.
Yes, I understand this too. If this is directed at my comment regarding not doing any structured workouts, FYI I was still riding, just outdoors and with a power meter.
I’ve already flagged rides with obvious incorrect PP values. There are MANY others where the PP/HIE falls outside the bell curve but I haven’t flagged them because those values are the same as I’ve seen MANY times in the past when they had no obvious effect on my Fitness Signature. Just looking at the table, I’m not seeing what caused the jumps in my signature. I suppose I could just flag the rides that seemed to trigger the jumps but that wouldn’t be very scientific. What other figure of merit can I look at for the rides that caused the jump or is it just easiest to flag rides that cause jumps? If the latter, why doesn’t Xert do that for me or ignore or at least warn when those happen? Also, do I need to manually force a signature refresh after flagging?
Flagging removes the entry from signature calc and adjusts forward at the same time.
The recent updates to signature calculation include a fix for overstated HIE that some users were experiencing.
Unless your current numbers are outside the bands on PPI/HIE chart you can reasonably expect your signature is in the right ballpark according to Xert’s methodology. That won’t necessarily match other platforms.
If you feel differently adjust the numbers manually and see where things go from there.
Lucy is an over/under LTP workout and that is how it should feel (RPE). On EBC that means conversational breathing during the blues rising into rhythmic breaths during aqua intervals.
Luch is one of my go-to workouts for mindlessly watching something on YT or TV.
If you can’t ride Lucy for 1-2 hours without much fanfare something is off.
Would I ride it for 3 hours? No way. YMMV
I haven’t checked any other platform or used any other tool to compare to Xert. The current PPI/HIE values, and those from about the last month are in line with the bell curve.
Per Lucy in the Sky with Diamonds 180 comments: Long slow distance (LSD) is the best way to target building your Threshold Power. Add large doses of low intensity training load to your training by spending time doing this simple workout that targets an intensity that you can maintain for hours. Try and do these workouts by feel and without trainer control."
In the past, that workout felt like the LSD as described, but your description matches the workout being generated by Xert now. It went from ~79% to 94% FTP for the “over” portion! That’s a HUGE change! What does it show for you?
As if that change alone wouldn’t have been difficult enough to absorb, my LTP went up in even larger steps than TP, at the same time at the erroneous steps up in TP. My LTP is now above what my TP was 3 months ago! That would be wonderful if true, but at 55 years old, I know a 50 watt increase in a few months is a pipe dream!
It looks like the erroneous LTP is what is causing all the trouble for me at the moment.
I think I’ll try flagging the Breakthoughs that I suspect are wrong and see what happens. I’m worried that will just cause a new Breakthrough on a ride following each of those so there will be an endless string of flagged ride data. At least that’s what I’d expect if the power data were bad (and I suppose the right thing to do if it is indeed bad). Other than peak power, I find it really difficult to look at power data and see obvious errors. I guess I just have to be more suspicious of Breakthroughs going forward…
I suggest you file a support request and ask for LTP confirmation/adjustment or raise HIE yourself on last activity, Save/(Lock), then note the LTP change on XO home page.
You could also ride the workout as described in Slope mode by feel (RPE) and estimate what wattage you think your LTP number should be. For most it is close to LT1.
I just flagged a bunch of breakthroughs then chased down the new breakthroughs that popped up and finally got what could be realistic numbers. That’s about all the time I have to spend on this. Hopefully whatever is wrong with Xert sorts itself out soon or just disappears if it was bad power data. I suspect it was the latter but what’s a person to do about it other than buy a new power meter?
YMMV