Hello there,
I just registered to xert and find the overall experience (website, concept, apps, …) very very nice.
I have one question about smart workouts though:
Given I train with erg mode on a smart trainer: how can the workout adjust on the fly? How does it know if I barely hit the targets and hang on for dear life or if I ride free handed browsing through my smartphone? Since I’m in erg mode the algorithm shouldn’t know, should it? What am I missing?
I may completely misunderstand you, but no matter the mode, you will be reporting the Watts you generate to the app.
In ERG mode, it may be harder to hit your target, but that’s a personal thing, also depending on what type of training you do. I.e. with lots of short high power intervals, or longer sub TP ones.
In Smart mode, the Xert app controls your trainer and adjusts the Watts. Some trainers respond better than others, but it’s also a matter of anticipating the changes, by slowly adjusting your RPM, just before intervals start.
Thank you for your answer. You’re right, there is a misunderstanding. Let me try to rephrase:
If I understand correctly, xert’s feature “smart workouts” adjusts the interval targets during the workout, based on what I’m capable right in that very moment, ehich is not necessarliy what my fitness signature suggested when I started the workout. Maybe I feel great and smash every interval (then it would give me higher targets), maybe I feel terrible and struggle (then it would give me lower targets). Am I understanding this correctly?
If the above is right, how can the “smart workout” know if I’m feeling great or if I’m struggling? The only way I can think of, is if I stop pedaling, then obviously the numers were too high. But how does it know I managed an effort just barely or if it was easy? Analyizing the power data of the interval (spikes and drops which indicate a struggle) can not be the answer if using erg mode.
Hi Chewie,
Here is the guidelines for SMART workouts…
Taken from that…
When a workout is opened in the Workout Designer, intensities and durations are auto-calculated using your Fitness Signature. Rather than using simple %FTP and fixed duration intervals, Xert adjusts your targets and the interval durations to fit your specific abilities. For some, this means higher intensities and for other it means lower intensities. Some intervals get extended. Some get shortened. Workouts adjust to you automatically by our algorithms.
Ok, that answers my first question basically with “yes” 
–> Xert adjusts your targets and the interval durations to fit your specific abilities
I might add: Xert adjusts your targets in real time in that very second you perform the workout
However: How does it know how to adjust? How does the algorithm know what my “specific abilities” are in that very moment? Say I have a 10 minute interval at 250 watts prescribed. If I hold exactly 250 watts for 10 min (which you do when using erg mode), how can the algorithm tell if the 10 min at 250 watts were “just right”, “too easy” or “too hard”?
I think you have a misunderstanding of what a smart workout is. One of the admin guys should be along soon and could perhaps provide you with further information.
I indeed think you are right.
One more point of clarification:
“Rather than using simple %FTP and fixed duration intervals, Xert adjusts your targets and the interval durations to fit your specific abilities.”
Ok, so basically what Sufferfest does with it’s 4DP model just that xert adjusts on a daily basis and more maxpower datapoints yada yada
Where it gets interesting and sets xert really apart is this:
“Workout players also use advanced mathematical models, in real-time, to adjust either interval power or duration to assist the athlete in meeting the goals of the workout.”
I just can’t get my head around how the interval power could be adjusted in real time
If you take a look at the sections “Dynamic Duration Smart Intervals” and “Dynamic Power Smart Intervals” this explains how it works…
Makes more sense - in the meantime, others have chipped in on the topic of ‘smart’ workouts, so I’ll take my leave 
Thanks for pointing me towards the right articles. Why read them myself if I could also ask stupid questions, right? 
Let me phrase this extra provokingly just for the arguments sake:
If (and only if) I manage to perform my workouts exactly as prescribed, “smart workouts” have absolutly no benefit.
I don’t think so. IMHO, they wouldn’t be ‘smart’ if you can execute them exactly as prescribed. Any of those, will most likely be executed differently every single time you do them.
Then again, I’m not that smart, so I might be wrong 
like it
And this is exactly what I doubt massively. Take what I have prescribed today “Smart - Save yourself 90”
On a trainer with responsive erg, I reckon I do this 100% as prescribed today, tommorrow and in 2 weeks.
Maybe you could, given that this is one (of several) less obvious smart workouts, since it targets LTP and has fixed/even intervals. Even then, you could still have different outcomes any day, when looking at 40 XSS per hour, buy okay…
Try Tabata’s or something like Raining Blood…
Ride some more and you’ll see why and how it works. 
Here’s my take on it –
No ERG workout is exactly on target for the duration of the interval. No trainer responds that fast and neither do your legs. It’s constantly up and down and dependent on how smooth you pedal, cadence, and how fatigued you are.
Some smart workouts only include smart efforts (the work portion). Others only include smart recoveries. Some include both.
Watch what happens if you coast during a smart recovery. Suddenly a 60 sec recovery gets a LOT shorter because you stopped pedaling (recovered faster). The same principal applies in reverse. Push harder on the work portion and it will shorten the effort. How much so likely varies by rider based on their equipment (power meter or trainer), pedal stroke, and fitness signature.
Bingo! I encourage people to test with the workout designer and workout players to see how our concepts work.
Thanks for the numerous responses. Just trying to wrap my head around how it could technically work.
For the rest of what xert offers - I decided not to use the 30 day free trial but to subsribe right away. Even if I don’t end up using it, I think the platform deserves the 10 dollars
So yesterday I did SMART - The dog days are over.
If you look at the workout designer you can see which intervals are meant to be dynamic in duration. In this workout it’s only the micro-micro sets (where recovery duration is to a % reserve MPA) starting at 25min (for the first set), and that’s not actually the part of the workout where you did your surges etc.
Try something like ‘SMART - Iron Man 45’ for a workout that has % Reserve MPA enabled for both work and recovery segments of the intervals.
Or ‘SMART - Ride the Lightning’ for something more severe.
