If you are/become a WKO user, the 2 metrics (in addition to FTP) that I would suggest you monitor are your TTE and FRC. Building your TTE (a measure of how long you can hold your FTP) is a good measure of your short term fatigue resistance (Stamina is a measure long term fatigue resistance, typically useful for century riders).
FRC (Functional Reserve Capacity), measured in Kj, is a good metric of what you have in the tank for late in the event. FRC is typically very useful for road racers (i.e. to know what they have left for a sprint finish), but is probably pretty good for CX/XC due to bursty (over threshold) demands. Long term, it will be great if they can accurately model anaerobic battery (dFRC) and make it available real time (but Tim Cusick said that this part is not a WKO initiative).
Well I know the TTE definition and heard about it in webinars. Iām really not sure what to make of TTE, sometimes I think of it as a vanity metric because my hard rides tell me more. For example during a season I cranked out a bunch of 2 hour rides at .9 IF and watched my TTE jump around between 37 minutes and 60 minutesā¦ Long hard ride - TTE jumps to ~60 minutes. Three weeks later and it falls to ~40 minutes for a week or two. Then another hard ride and TTE jumps back to ~60 minutes. Over and over again, as I do a really hard ride about every 4 weeks. My set FTP and mFTP were almost identical during that time period. I wasnāt even using WKO at the time. Not finding TTE metric particularly useful, maybe if you only do 20-minute SS-threshold intervals? I donāt know. There is a lot of stuff I could monitor, this one doesnāt make the cut.
Time to Exhaustion (TTE) is simply the maximal duration you can hold power equal to FTP. Numerous research studies have determined this to typically fall in a range of 30-70 minutes. TTE is simply the point you drop off of FTP power and will not recover (small red box in image). Of the Power Duration Curve (PDC) metrics it is the most sensitive. Why? Well think about the PDC (or even your MMP curve) it tends to be very flat from around 8-10 minutes out to TTE. This means small changes in watts / performance can have larger effects on TTE due to this āflatnessā. Meaning adding a few watts at some time point, say 1 hour might move the curve slightly but push the inflection point out significantly. This typically will not happen when you have a robust data set of 60-90 days but when using WKO initially (or restarting) it takes a bit of time and efforts to smooth it out. With a robust data set TTE is pretty solid and can be used to help plan training TIZ. For data sets that are not as robust or more variable, I would use more as a guide and think about it this way: 30-40 min TTE short, 40-50 min TTE med, 50-60 min TTE long.
The case study is this. Take two athletes i coach. One is a TT specialist and the other a Crit racer. I track TTE for both. For the TT racer, we train a fair amount of time at FTP and have a robust data set. We use our event time target (say USA nationals predicted at 32 minutes) as a key target. I really donāt try to raise TTE beyond that, we focus on power for those 32 minutes. We use TTE to target Time in Zone on workouts. For the Crit racer, the data set is also robust and general stable but more stochastic / variable. I basically use her TTE as a guide for time in zone training but do not measure the output as precise, just basically track if she is āshort, med or longā as stated above.
Thank you! Iām actually signed up for your webinar tomorrow (Aus time)ā¦ āBuilding FTP, TTE, and Stamina with WKO5ā so looking forward to learning more about this
(Hoping to learn more about how to plan and direct TiZ based on the metrics)
There are some things in WKO that have obvious value if I were coaching 5 or 10 athletes, and TTE is one of them. As a self-coached athlete primarily using WKO as a flexible tool to do my own data mining, I have a different opinion.
Thanks Tim, really appreciate you dropping in. Also wanted to thank you for the webinars, they are a great resource!
If I buy this version it will reside on an older macbook pro with highest available RAM and an aftermarket SSD. Is it pokey and irritating or ānot horribleā. Iāll be coming off WKO3 and an antique PC.
Am 100% not going to a cloud based solution and have danced with GC a few times and find it interesting but not what I want for daily use as my computational skills arenāt there (my issue not GCās)
Even after letting it āsettleā, it was still slow for me on a fairly high-spec 27" iMac. Granted I do have 15+ years of power data, but it was just too frustrating to use. The new features werenāt worth it for me so I decided to stay with WKO4.
BTW, I still long for how fast WKO3 was. Not sure itās just due to having more power data, but seems that each major release just gets slower and slower.
I have a 2013 MacBook Pro and have had no speed issues since the first day of use (I purchased it soon after the launch).
Regarding usability: It took a bit of getting used to having come from WKO4, particularly the colors on black (WKO4) vs colors on white (WKO5), but now very much used to it and indifferent to it.
Todayās webinar was the final in the 4 part WKO5 introductory series:
Getting Started with WKO5
Individualizing your Training with WKO
Building Pmax and FRC with WKO
Building FTP, TTE and Stamina with WKO (todayās webinar - fantastic!)
Important note re: future webinars:
At the conclusion of todayās webinar, @TimWKO announced that in mid-October he will begin a new series of webinars on Advanced Training with WKO. HOWEVER, unlike webinars to date, you will need to be a WKO5 user in order to register. Your WKO5 registration code will be required at webinar registration sign up.
MacBook Pro 2016 with 2TB SSD and 16GB RAM (2.9GHz Intel Core i7). This is basically the top-of-line MBP.
Approximate load times of āWorkout Dashboardā
WKO4 takes ~3.5 sec
WKO5 takes ~4.5 sec
Every single panel shows āWorking on itā¦ā and in particular, āPower TiZā is really slow. And Power TiZ is 0.5+ seconds slower to load in WKO5 (versus WKO4).
Comparisons:
open web browser, go to TP (Iām using free to feed WKO4), click a workout, then click analyze and it loads in under 1 second
rarely use Golden Cheetah, but launched it just now and switching between workouts the charts load almost instantly
So Iām not hallucinating, charts take 1+ seconds to load and then Power TiZ sits there for another 3+ seconds before it loads. And it loads faster on WKO4, so that makes WKO5 feel slower. Plus in both trials (July launch, and right now), I can consistently and repeatedly crash WKO5. Where do I sign up for the beta testers group? Can I get a discount? My fault for buying WKO4 earlier this year, because my software marketing āspidey senseā knew WKO5 was coming soon.
Like I said a little annoying compared to other apps on this same computer - earlier comment I was mainly thinking of complex PowerPoint or Word docs but did a little investigation to backup my earlier statement.
Not sure if you are doing this, but if you are switching back and forth between WKO4 and WHO5 you will see slower performance due to the way the files are cached.
Iāve been running WKO5 for 2 days or so, and then just performed some stopwatch benchmarking. After the launch I learned my lesson and made sure WKO5 cached everything.
The Power TiZ loading time was so painful that I finished doing some tests, quit WKO5, and started WKO4 for comparison. WKO is just slow at refreshing charts, always has been from where I sit. It is the only āslow appā on this MacBook Pro. Iām not a software dev, but routinely compile stuff that takes 20 minutes to 8 hours. It is not that slow, and Iām generally patient with software, so maybe sluggish is a better word.
I took advantage of the 2 week trial but donāt think Iāll be making the purchase. The info is nice to have, but didnāt really tell me anything that I didnāt know from TP. I can also see getting some analysis paralysis and spending lots of time micromanaging my training that could be spent on the bike.
Oddly enough my mFTP in WKO5 and Stravaās FTP estimate (which I didnāt even realize was a feature) have been matching perfectly across various timelines
yup. I mainly use WKO4 to help analyze previous training and it has helped in that regard. Iād see more value using WKO if coaching a bunch of athletes. But for my own day-to-day training Iām all in on using TrainerRoad plans with modifications.
Question for the forum - does anyone know why time in Classic Coggan endurance level does not align with time in endurance iLevel? At endurance level the power range for classic and iLevels is identical, however the WKO4/WKO5 graphs donāt show that. Here is a WKO5 graph (WKO4 is similar):
Maybe they will hang onto Facebook group a little longer, in a quest to increasingly ratcheted up friction with customers 
pay me now or pay me later 
