Workout Mode - ERG not providing enough resistance

(Michael O) #1

Hi there!

During my first experience with workout mode there were a couple of instances where no matter how quickly I pedaled, or what gear I shifted into, I was not able to maintain the target wattage. It was like all of the sudden the trainer’s brake turned off and I was spinning at 130 rpm bouncing around in the saddle trying to put out a measly 185 watts. Although comical, I was a bit confused as to why you’d want me to spin my brains out for 5 minutes at such a low wattage.

My trainer (tacx vortex smart) was also reporting very low cadence during the beginning of the ride - like 23 rpm. My avatar looked like it was barely moving its legs. It finally caught up when I shifted into the big ring, but the cadence was constantly inaccurate, as compared to the regular non-ERG mode - is there a particular ring / ratio I should be in while in ERG mode for the most accurate info?

Another question regarding the ERG mode - should I ever need to shift gears during a workout, or will the trainer always adjust accordingly? 

Also, there was no suggested cadence during the workout. This led me to slog through parts of the workout at 60 rpm, sometimes lower, that is until I realized that in ERG mode the trainer automatically adjusts to an increase in power/cadence. Are there any plans to include a cadence target during workouts? It felt like there was some sort of cadence / watt control going on, as sometimes I’d find it very easy to pedal and needed to rapidly increase my cadence (up to 130+ rpm) just to maintain my wattage output. If there is an internal cadence control, and not just a wattage target, it is not clear, and doesn’t seem to be working correctly.

As mentioned in other posts, having the upcoming events on the left side was nice, but I still had no idea what the next watt target was going to be once inside a block. This meant for the SST training I wasn’t sure if at the end of a section I was about to rest or kick it up a notch. It would be nice to be able to see the whole workout visually to allow me to be a bit more psychologically prepared for what’s to come.

I also want to say thanks for putting all the hard work into developing this app - I’m totally hooked just after a few rides, and I’m glad to help in any way I can to make it better for all of us Zwifters!

tl;dr noob spins legs real fast, gets confused. is curious about cadence targets during workouts and is really grateful for the zwift team’s hard work.

(Dominic Moran) #2

Michael I have the same issue with respect to really low resistance when I select a workout program. You end up just bouncing in the saddle doing a stupid cadence and producing little watts. 

I have now dropped a training program as it simply wasn’t giving me a workout and I just do a ride which correctly adjusts resistance with respect to gradient etc as it’s the only real way of putting some watts/effort in.

Therefore it would not seem to be a problem with my bike set up but the ERG workout programs.

It would be great if the team at Swift could resolve this as I think this is an important part of indoor training that I need to do in the dark winter months?




(Rod Olliver) #3

I’m on a vortex too.  I haven’t had the spinning issue, you guys have had, I don’t think.  One thing I notice is the cadence seems to be more accurate when using a bigger gear than 39x25, may just be me…  Maybe would be good to use a different source for cadence?  I haven’t managed to get my garmin cadence sensor to pair.

Was there a workout in particular you had problems with?

Re: No suggested cadence during the workout

  • I am doing the 12 week Winter plan, on week 5 now and there are cadence workouts, yesterday was doing high cadence (130+ for 1 minute), today it was low cadence, where there is a suggested cadence of 50.

  • I usually ride at 90-100RPM and the ERG adjusts the power to match what’s in the workout.  Often I increase to 105-110, when doing some endurance work just to break things up and try and be more efficient, power adjusts no problem

- I did have some really hard 1 leg drills, (1 minute/leg @ 180W)

My problem that brought me here today is that it seems the Vortex in Erg-mode has a minimum cadence of 60, where if you pedal slower than that, it just tells you “More Power”, as soon as you hit 60, but the workout (week 5 day 2, 12 wk winter) asks for a cadence of 50.  If I pedal at 50, it says to go harder.  Instead I just did at 60rpm

Pretty happy with workout mode, there have been some little issues, but it’s still new.  Ride on!

(Jin Park) #4

I have elite smart digital B and have similar kind of issues.  I am in too high of gear for the given power I am doing for SST.  Also seems like the resistance control is turned off… or set at certain pre-determined value and doesn’t respect the slope I am riding against.  I would imagine upping the resistance for higher wattage would work nice too… too keep optimal cadence for lot of us if not going to reflect the terrain…?  Is this some kind of oversight or…?

(Jason Prosseda) #5

Tacx Neo

John’s Short Mix for example:

I’ll miss 3 or 4 of the 10s 700W even if I try all kinds of cadence tricks before and during the interval.

I am even missing some of the 30s 115W rests because I think something goes wrong coming down off that high power.

In general, when I vary cadence the erg does not adjust to me fast enough to give me a full star for that part of the workout.

I also assume the resistance of hills setting does not get used in erg mode, correct? And instant or 3 second power average has nothing to do with resistance?

(Gus Goad ZHR (G)) #6

It seems a year on from the last post that nothing has changed. 

I have a Tacx Vortex and experience these very problems. I have a separate cadence sensor but ERG workouts are a complete waste of time. Zwift have raised a ticket but have no answers yet.

The same thing happens on Trainer Road and the Tacx Training app.

(Thomas Heidbrier) #7

I have a wahoo kicker ver 2 that is doing the same thing. Opened a ticket with wahoo this evening. Zwift didnt have an answer.

(Gus Goad ZHR (G)) #8

I have worked out that ERG on my Vortex works OK at relatively steady intervals around threshold. High power spikes, however, forget it. 

I now workout with ERG switched off -  a bit of a faff finding the right gears but at least I can get a workout.