Some Workout mode Feedback

(Jim Hansen (Seattle)) #1

I have some suggestions about Workout Mode.

  • Please, please, PLEASE , for all that is good an holy,  allow us to ‘pause’ a workout. Without the ability to do this, having a workout more than about 45 minutes is useless.  For me personally, I’m rehabbing from a serious shoulder injury. I’m just back on the bike and attempting long slow rides, re-acclimating myself to the bike.  The fact that I’m failing workouts because I need to stop and stretch a sore shoulder, neck, or take some pressure off the seat, is downright ludicrous.  The ‘pause’ would be optional. If people think it’s cheating (themselves!), then by all means, DON’T USE IT.  For me right now, this is a deal breaker for workouts in Zwift.   Please enable a simple ‘Pause Workout’ button.
  • ERG Mode is almost useless in most situations.  I use a KICKR and find that between Zwift and the KICKR, the resistance changes are too slow to accommodate transitions. Especially for short segments that involve large power changes (i.e. Sprints)
  • As a follow on to the ERG mode comment, please remove ‘pass/fail’ criteria from workout segments if ERG mode is enabled.  The ‘system’ determines my power output (as long as I’m pedaling), so I have no control over whether I pass or fail a segment.    I find I’m continually failing segments (especially cooldown segments) in ERG mode because the power transitions are sloppy and slow.


(Jon Mayfield) #2

Hi Jim.

Good news - pausing a workout is a feature being released within the next week (if you have the phone app).

I disagree about erg mode being “almost useless in most situations”, and  I’d argue it works great in 95% of all the situations.  The slow transition is down to your device - each trainer changes between erg modes at different speeds. It isn’t within Zwift’s control at all.   We’ve been in talks with Wahoo to see if they’d be able to expose control to us for that “blend time” between different erg values. Other trainers hit harder (Computrainer), some blend softly (like the Cycleops, which probably take the longest time).  Wahoo is on the softer side.

As for the pass/fail, the first 7 or 8 seconds of any workout block do not count at all towards pass/fail.   Is your kickr taking longer than that amount of time to adjust?

(Jim Hansen (Seattle)) #3

Thanks for responding Jon.

Thanks for the news on the Pause feature.  My butt and my bladder are particularly happy about this. =)

Perhaps you are right. I might have overstated the issue with ERG mode, but it’s still very frustrating.  I’d also argue that ‘95%’ might be overstating it’s usefulness.  That would be a stretch even if it worked perfectly (some workouts are just not well suited to it).

It’s interesting that you say it’s the device.

I do ERG mode workouts on a KICKR in Perf Pro Studio at my local bike shop every Monday/Wednesday/Friday morning, and have never noticed this ‘lag’.   I also personally used to use Trainer Road and never noticed it there either.

One possible explanation is that I notice it more in Zwift because it causes me to “Fail” a segment on occasion.

As far as 7 or 8 seconds… that’s an eternity in a 20 or even 30 second sprint segment.

The shorter the segment, and the lower the power requirement of the segment, seems to be a contributing factor (i.e. low power cooldown segments seem to be affected more).  I admit that my sample size is small.  I’ve done a half dozen or so workouts now. (I’d love to do more though).

If I might ask, what is the purpose of the pass/fail thing? What criteria is used?

It seems to be that the determination of whether or not I successfully performed a training segment should be entirely up to me (and my coach/trainer) based on criteria we determine based on my training goals (heart rate, recovery, sustained power over time, etc…).   Certainly the consistency of my power output during a cooldown segment is not a criteria that I would use to evaluate the success of my workout.  

Perhaps in a future update, you could just make the pass/fail thing an option the user can toggle on/off per segment or per workout (or even per session)?

Given a choice, I’d certainly turn it off entirely.


Thanks for listening. =)



(Pete GameCock WBR (D)) #4

Taking away ERG mode would be as bad as taking away my birthday. I use a Tacx Vortex and have hit virtuall all of the targets up to week 8 of the 12 week FTP builder. I like seeing the stars and bonus points. I look forward to every workout. Keep up the good work

(Michael Henasey) #5

ERG is primary reason for using a smart trainer.

I have a KICKR. If you took away ERG mode I’d sell my KICKR on eBay and go back to riding rollers.

There is a lag with resistance changes in ERG mode. I’d say about 2-3 secs. Do I wish it was instantaneous? Yes. But it’s not a big deal. I know 2-3 sec. into an interval the resistance will change and 2-3 sec after an interval the resistance will change. I’m still completing the interval at the correct duration and I still get my stars :slight_smile:

@Jim, I wrecked my shoulder last March and while Zwift didn’t have a workout mode and ERG mode then, I wish it did. It would have made my rehab time easier to deal with if I could just set the resistance and ride along without having to deal with changing gears. Good luck with your rehab.

(Duane Gran [Vision]) #6

Do I wish it was instantaneous? Yes.

Be careful what you wish for.  It is really quick on the CompuTrainer and if the transition is steep (going from 100w to 450w, for example) it can be quite challenging in ERG mode.  I’ve personally found that short and intense efforts are best done in sim mode but I know preferences are all over the map on this matter.

(Michael Henasey) #7


For “sprint” or “bursts” I usually setup a free-ride block in a custom workout. 

I can somewhat agree with your warning about an instantaneous ERG mode. If the change was not anticipated, yes, it would be quite jarring to go from 100W to 500W. However, the portals and the countdown timer gives me ample warning that the interval is changing and I can anticipate the change in power (e.g speed up cadence, stand, etc.).

If they (i.e. Zwift and Wahoo) could make ERG mode instantaneous, then they could make it the same way in SIM mode when you are just riding the island and the gradient changes in-game would be reflected in sync with resistance changes. The short & steep dip in the Esses is a perfect example. The resistance changes are sharp but out-of-sync with what I see in-game and that certainly does detract from the overall experience. 


(Jim Hansen (Seattle)) #8

I’m not advocating taking away ERG mode at all.  It definitely has it’s purpose, and it can be disabled for workouts if I choose not to use it.

I’m just trying to understand how I can fail a (segment in a) workout while in ERG mode.  The ‘system’ determines the resistance. As long as I’m pedaling, the power output is (supposed to be) the same, regardless of my cadence.Short of not pedaling at all, I don’t see any reason to fail someone in ERG mode,but it continues to happen to me, particularly on cooldown/recovery segments.

(Michael Henasey) #9

@Jim I don’t believe your experience is normal. I haven’t heard of others reporting a problem with being able to maintain wattage in ERG mode and often failing blocks. the only time I fail a block is if I stop pedaling for about that 7-8 second time period Jon M. mentioned above. that has generally happened when I needed to stretch or adjust my shoe. now with the new pause feature added today, should be a non-issue.

is your KICKR calibrated? latest firmware?

is your ANT+ signal strong? experiencing dropouts?

when riding in ERG mode with the KICKR, what gear are you in? I have found that riding in a large gear works best. this keeps the flywheel spinning faster. I ride around a 52/16 all the time. right in the middle. minimal chain line deflection. keeps the flywheel spin high.

have you opened a support ticket with Zwift?

can you provide a video showing how you fail these blocks?


(Jim Hansen (Seattle)) #10

I don’t have any video. I might have a screenshot or two of the failures.

My KICKR is calibrated. I run a spindown once a week or so.

When I ride in ERG mode, I usually ride in my biggest gear (50/11) for the reasons you mentioned.

My ANT receiver sits under my bike via a USB extension cable, and all of my connectivity seems to be fine (not having trouble with other sensors, and the KICKR works fine).

I’m not new to indoor training. I’ve been cycling since the mid-80’s. Indoor training (rollers, fluid trainer) has been part of my off season for many years. I’ve owned a KICKR for over a year, and ride in a indoor cycling training class in my local bike show a few times a week during the offseason (also on the KICKR).

I generally ride with my cadence fairly stable (about 80 or so), although I might change it up (higher cadence for some threshold segments, or lower cadence for short, high power climbing simulations).

I’ve not noticed any issues with ERG mode workouts using other programs (i’m experienced with PerfPro Studio from the rides at the shop, and used Trainer Road at home quite a bit last year). That isn’t to say those programs work flawlessly with ERG workouts. It’s possible that similar issues exist. It’s just not as obvious to me since those don’t ‘fail’ me on a segment if my power output is low or high (I’m not even sure what the pass/fail criteria is for Zwift Workouts, which is part of my frustration).

The segment failures have happened several times now. Almost all (if not all) of them were in recovery/cooldown segments. I don’t recall having trouble with higher power segments or sprints, etc… although i rarely do workouts with hard/short sprints in ERG mode.

I’m not sure if it factors in, but I am probably an outlier in terms of my rider weight. I am 6’ 5" and a little over 250lbs.

Also, I’m currently riding with my FTP set a little low (around 225) intentionally. This means the power requirements for the cooldown/recovery segments I’m having trouble with is particularly low. I’m doing this because I’m rehabbing from a serious shoulder injury, and I’m really just re-acclimating myself to the bike after six months off. I’m going for longer, lower power workouts (when I have time) rather than shorter, threshold work.

I think the best solution for me is to just ignore those silly stars, at least until I figure out what’s going on. The entire thing has gotten a little over blown (perhaps too much hyperbole on my part). The first time the failure happened, kinda laughed about it… “How can I fail a segment in ERG mode”… I posted about it here, and it kinda snowballed from there.


(Kevin Carlson) #11

95% of the time its working? I find that hard to believe… Every workout I “Fail” according to Zwift on my Tacx… where is the documentation that explains the algorithm on Pass/Fail? Perhaps the user interface is not allowing us to understand what makes a pass or fail. Perhaps after a workout explain why we failed… 

I just did a workout and according to Zwift I failed miserably, but I kept my wattage way above my intended wattage for the short intervals due to the 5 second lag in adjusting the power on my tacx. Interestingly the recovery sessions I never fail… its just the 1 min and shorter intervals. 

(Jon Mayfield) #12

Hi Kevin.  The first 7 seconds of each interval don’t count at all for stars either way so I wouldn’t worry about that.

What you should do is try to do the interval as prescribed.  Going “way above” the prescribed wattage will cause a fail, just as going below it will.   It’s not about the average, it’s about the time spent doing it at the prescribed value.

(Jim Hansen (Seattle)) #13


Why would you fail someone for going above an effort on a workout?  You aren’t just not giving them a star.  You are also not giving them experience for that segment.  This seems a bit harsh, when someone might be feeling a little extra the end of a workout and want to push themselves.


Not everyone who is using the workout system is doing textbook training programs.  Sometimes we are just wanting to have a goal, or, I my case, I use workouts to maintain a steady effort over a long steady ride.

If I end up too tired towards the end, or feel particularly strong, I shouldn’t be punished by being denied XP.  This is especially painful if the segment is long.

(Michael Henasey) #14

You color outside of the lines, you don’t get a star.

(Kevin Carlson) #15

John I will try what your suggesting but I know already that in this workout I did do, the earlier intervals I tried to do as “prescribed” failed me as well because my Tacx was not allowing me to hit the numbers that were being subscribed due to Zwift not showing the correct numbers. It seems there is more than a 6 second lag between Zwift and Tacx updating. 

I tend to also agree that you should not be decremented based on going over thresholds, if someone for example was constantly going over thresholds and still successfully completing the entire workout as such, then perhaps suggest a new FTP test rather than decrement or FAIL. 

Likewise if an individual was to go hard in the beginning (as a beginner rider) they will soon realize they cannot hold the numbers and will FAIL… this should be the expected procedure. 

(Steve C) #16

I have to disagree about being ‘allowed’ to go over power in an workout. Zonal and interval training stresses different parts of your physiology. If you’re hitting the interval too hard, you’re not working the parts of your system the workout plan is intended for.

(Jim Hansen (Seattle)) #17


That’s great if were doing that kind of workout.  Most of us are just hacks, using workouts to add a little structure to our riding.   I am all for having some feedback, or even a nice report at the end of a workout to tell me how I did on each segment.  Just don’t take away my game “experience” (leveling) for not completing a segment withing the HIDDEN parameters.   

At this point, we don’t even know what criteria the “game” is using to determine pass/fail. Is it average speed over time? over distance?  some combination of criteria?  What is the acceptible range? We also aren’t giving any visual feedback to know if we are above or below whatever the criteria is.  Should I speed up? slow down?  stay the same?  

Take away the star, I’m fine with that, but don’t not give me XP for ‘failing’ when I don’t even know what it means to ‘pass’.

(Kevin Carlson) #18

Steve you might be mistaken on some of your statement above: First having some education on the subject your comment on: “Zonal and interval training stresses different parts of your physiology. If you’re hitting the interval too hard, you’re not working the parts of your system the workout plan is intended for.” 

Anything above threshold is for the most part… Above aerobic/vo2. So you’re just engaging more type 2 A 

Which is the point. So if the workout is set to 120% of your FTP, this workout is essentially taking you to your max and your adding capillary and mitochondrial density, if your able to go above the 120% then GREAT… You still succeed you have still engaged your fast twitch, as these intervals are mostly short HIT. (If you cannot finish your workout due to going to hard then YOU FAIL)

Now if you were to say have an athlete go out for a 3 Hour Tempo Ride… and they go above tempo then YES, you would be negating the need to ride tempo, and now have engaged in anaerobic training. Thus the reason on these workouts with ZWIFT I never fail the recovery… because they are usually longer and steady. 


(Kevin Carlson) #19

So John, Going “Way above” on short 15 second ceiling intervals should NEVER fail… They would only ever fail if you are way UNDER… the intended high interval

(Dan Schaeffer) #20

How do I pause a workout?