Drawbacks and/or benefits of ERG mode

Triathlon Forum
1

I’ve been thinking about this for a while and recently listened to an Empirical Cycling Podcast about this very topic.

My question is this: what is the benefit of ERG mode, especially for triathletes?

As an athlete and a coach, I really see not benefit. If anything, I see it as a hinderance to listening to our bodies and dialing in efforts. Many folks plug in a certain wattage, but the fact is our FTP (or CP) fluctuates daily based on recovery or fatigue. Having a wattage range and fitting a given set of intervals within a range is far better than sitting on one certain number. We obviously don’t have ERG mode when riding outside, and getting too tied to it probably hampers performance when riding outside. We never ride at one specific wattage, even on a very flat course or area, watts always fluctuate. I feel it’s much better to get accustomed to a bit of variability and listen to our bodies instead of zoning out.

I’m curious to hear from those who think there is a benefit to ERG mode.

2

I think it can benefit.

-Can zone out on easier paced efforts without the watts dropping off.
-Can help you push right towards the end of harder intervals.

I agree using it all the time probably isn’t great if you don’t ride outdoors much.

The software apps are easy enough to dial the intensity up or down a bit depending on feel.

One of those things that if it helps you enjoy training more then can only be a benefit?

3

I don’t have an issue with erg mode but I do think it’s not good to lock most of your training into it, as you’ll miss the edges of what your body can deliver if you really push when it counts.

A practical issue I’ve run across that also limits the utility of erg mode is that that smooth erg line your Kickr or whatever power device draws, may not be as accurate as it seems. At least with my early-gen Kickr, the erg mode power line looks super smooth if reading off the Kickr powermeter, but if I read off my Favero Assiomas at the same exact time, there’s a lot more fluctuation. Given that I’m racing withe Assiomas and not the Kickr, this is a minor problem - doesn’t kill erg mode which is still in the range I want, but it’s not as accurate to the watt as I’d previously believed.

4

When I first got my Core 4 years ago I was excited to use ERG mode but after a few times using it I stopped. Never used it again. I just did not like it. It felt off to me. And part of what I liked about being on the trainer was changing gears and really being in tune with the ride. It also helped pass time. And the few times I tried I realized that it did not help me at all. I could hit the watts or I couldn’t. ERG mode did not help me “push” to get to the interval watts it just made it more annoying.

5

I think that the benefit depends on the individual and how they train. In my case, it makes a massive difference in overall training effectiveness (all my workouts in general, not just zeroing-in on a single workout).

I have to do almost all my training indoors, and it is mind-numbing. So, I prefer to watch streaming shows while doing the workout. This is very difficult with trainers in resistance mode, and I generally under perform my targets. With ERG, that is a non-factor. I simply ride the ride and the trainer does the rest. If I am fatigued, I can easily dial-back the effort level. But what I probably miss is dialing-up the level on the days when I am feeling stronger.

But the key is that I am doing 16 workouts a months for months on end. While a handful of my workouts may be suboptimized, overall they are far more effective with ERG because I am doing them better than I would be without.

On the other hand, for athletes who like to focus on the trainer app without distractions and adjust targets on the go, then resistance mode might be more effective.

6

LOVE the ERG mode! I wish i could say i was disciplined enough to say I don’t need it but riding inside can be so very boring I need it to make sure i am doing my watts.
With ERG mode i can watch a movie or tiktok or whatever and i am still forced to do the power. I am probably 4-5 months indoor and then 100% outdoor starting in springtime so i do get enough real ride feel in my opinion. With ERG mode i can ensure that i am not going too hard or too easy which is a problem without ERG mode. Sometimes i wish i could ride in ERG mode outside!

7

I’m not sold that ERG mode stops people from ‘listening to their bodies’ in the context of actual (outdoor) riding and racing. Sure, maybe ERG mode doesn’t teach you how to hit an exact power number on Zwift, but you’re also missing the balance, noise, vibration, and general sensations of cycling that inform your effort.

One of the biggest reasons people feel they can do higher power output uphill is that everything is softer, the sensation of speed isn’t there. It doesn’t take more than 5 minutes on a bike to mentally condition more intense output with more intense noise/vibration/movement.

On the road there’s plenty of non-power meter cues to help guide your output, on the trainer there is only effort. It doesn’t make sense to me that we should take away all of the real world information and then expect the ‘feel’ of the effort to be the same.

8

I think it can benefit.

-Can zone out on easier paced efforts without the watts dropping off.
-Can help you push right towards the end of harder intervals.

I agree using it all the time probably isn’t great if you don’t ride outdoors much.

The software apps are easy enough to dial the intensity up or down a bit depending on feel.

One of those things that if it helps you enjoy training more then can only be a benefit?

Both of these are things we need to intuitively know how to do. ERG may help during the workout itself, but in the long run is detrimental to doing things IRL.

9

I don’t quite know how to describe it but I feel like I’m constantly battling against the bike with ERG mode. Like, if I’m doing a hard interval and take a micro-break for a second, or my cadence starts to slow slightly, the gear just goes up to compensate and then I have to work harder to get back on top of it.

I guess that’s the point of it, to stop you taking any kind of respite, but I don’t like it.

10

I don’t quite know how to describe it but I feel like I’m constantly battling against the bike with ERG mode.

Yeah, I also don’t get a zen-like zone-out state in erg mode. I feel like I need to be constantly vigilant.

11

I only use Zwift on a Gen1 or 2 Kickr and I only use ERG mode for any structured workout. The only time I don’t use ERG mode is during robopacer or event rides.

I understand the comments about listening to your body, but I’m following a structured workout because I want to follow it as closely as possible, and have seen substantial gains as a result. When I try to do a workout with it turned off, I spend more time figuring out what gear and cadence fits that block than I do actually performing at the prescribed level. This obviously isn’t an issue while riding outside or in a group because you’re not trying to do intervals or ramps for specific power levels or durations outside.

Additionally, while in ERG mode, I can choose a gearing on the small ring with a straight as possible chainline to both extend the life of my equipment and lower the speed the trainer is spinning at which generates far less noise.

12

When I try to do a workout with it turned off, I spend more time figuring out what gear and cadence fits that block than I do actually performing at the prescribed level.

This is the key for me as well. Without ERG mode I felt like I was always adjusting my cadence to try to hit a power number and therefore was never riding at the cadence I wanted.

I one downside is when trying to do short sprint or VO2max intervals. For those, ERG mode just can’t react fast enough.

13

I only use Zwift on a Gen1 or 2 Kickr and I only use ERG mode for any structured workout. The only time I don’t use ERG mode is during robopacer or event rides.

I understand the comments about listening to your body, but I’m following a structured workout because I want to follow it as closely as possible, and have seen substantial gains as a result. When I try to do a workout with it turned off, I spend more time figuring out what gear and cadence fits that block than I do actually performing at the prescribed level. This obviously isn’t an issue while riding outside or in a group because you’re not trying to do intervals or ramps for specific power levels or durations outside.

Additionally, while in ERG mode,** I can choose a gearing on the small ring with a straight as possible chainline to both extend the life of my equipment and lower the speed the trainer is spinning at which generates far less noise**.

I think the idea of extending the life of gear is a compelling reason. This is the main reason I got a Stages Bike - don’t have to ride one of my bikes and go through components during the 7 or so months of indoor riding every year.

I also think that higher intensity efforts, especially shorter efforts don’t really work very well with ERG mode, especially sprints and max efforts.

14

A few years back I used ERG exclusively on the computrainer. Set it and go. I did turn into a fairly strong cyclist, but found paying attn to watts in races was a bit difficult. Eventually moved to a different coach and a smart trainer and have been non ERG ever since. JMO but I think it’s better to focus on a range of watts and try to hit it rather than be forced to.

I have used ERG a couple times recently for easy recovery sets as that ensures I don’t start chasing people on Zwift

15

I only use Zwift on a Gen1 or 2 Kickr and I only use ERG mode for any structured workout. The only time I don’t use ERG mode is during robopacer or event rides.

I understand the comments about listening to your body, but I’m following a structured workout because I want to follow it as closely as possible, and have seen substantial gains as a result. When I try to do a workout with it turned off, I spend more time figuring out what gear and cadence fits that block than I do actually performing at the prescribed level. This obviously isn’t an issue while riding outside or in a group because you’re not trying to do intervals or ramps for specific power levels or durations outside.

Additionally, while in ERG mode,** I can choose a gearing on the small ring with a straight as possible chainline to both extend the life of my equipment and lower the speed the trainer is spinning at which generates far less noise**.

I think the idea of extending the life of gear is a compelling reason. This is the main reason I got a Stages Bike - don’t have to ride one of my bikes and go through components during the 7 or so months of indoor riding every year.

I also think that higher intensity efforts, especially shorter efforts don’t really work very well with ERG mode, especially sprints and max efforts.

If extending the life of the gear is a priority then the simplest solution would be to have a dedicated indoor chain, or just cleaning the chain prior indoor use. Grit and dirt on the inside of the chain is a huge cause of wear. And most people ride outside on weekends, inside on weekdays, so not much changing about.

16

I wish I was able ride with friends more often, however my last outdoor ride was over 2 years ago. The nice thing about it is when I do show up for rides, I get to actually enjoy the time spent and be able to ride with them without strain and be able to hold a conversation from the effort and efficiency that comes with indoor training.

Also, though the odds are incredibly low, the risks of inattentive drivers up and down PCH here in SoCal continues to dissuade me from heading out on the road.

Also, I have a fanatically clean bike and the joy of not having to clean everything after every outdoor ride really is nice. Not interested in buying a new quick link every week due to swapping chains either.

17

With the advent of larger flywheels this has become less of a concern but i’ll still throw it out there… the dynamics of your pedal stroke change to one where you are trying to apply equal force around the whole pedal stroke revolution rather than simply the downstroke power phase of the pedal stroke.

In this case the trainer is riding you, not you riding the trainer.

18

I think that the benefit depends on the individual and how they train. In my case, it makes a massive difference in overall training effectiveness (all my workouts in general, not just zeroing-in on a single workout).

I have to do almost all my training indoors, and it is mind-numbing. So, I prefer to watch streaming shows while doing the workout. This is very difficult with trainers in resistance mode, and I generally under perform my targets. With ERG, that is a non-factor. I simply ride the ride and the trainer does the rest. If I am fatigued, I can easily dial-back the effort level. But what I probably miss is dialing-up the level on the days when I am feeling stronger.

But the key is that I am doing 16 workouts a months for months on end. While a handful of my workouts may be suboptimized, overall they are far more effective with ERG because I am doing them better than I would be without.

On the other hand, for athletes who like to focus on the trainer app without distractions and adjust targets on the go, then resistance mode might be more effective.

This exactly mirrors my opinion and experience. Since I do hours and hours of indoor training, I enjoy being freed up from the effort of trying to hit a power target and being able to just watch TV or listen to music and let my mind wander.

I’ll also add that I have zero problems adjusting to outdoor riding or racing. And really, I don’t use power that much in racing. I still mostly go by feel. During races, I have my average and normalized lap power on my headunit. I monitor it to make sure I’m holding a steady effort, not charging hills, or going out too fast in the first half of the race. But I’m not trying to hold some power target with any kind of real precision, like to within a few watts. In the end, my averages are pretty close to what you’d expect given my training numbers, course conditions, etc.

Bottom line-- I see no harm from ERG mode and it makes indoor training much more enjoyable, so why not keep taking advantage of it.

19

I think this is a really interesting question. Interested to see the responses. Anecdotally, I think people might be surprised at how much variety there is to the crank measured power even in erg mode. I looked at a recent steady cadence/power interval from Zwift and compared it to my SRM which is always running. Zwift power is measured with direct mount smart trainer, and has an incredibly smooth line. SRM power varied from 226 to 262 watts, averaging 242. Still less variation than I see outdoors even on a flat interval ride, but there is a larger deviation than you would perhaps expect, despite cadence staying very consistent. My hunch is that physiologically, it might not be all that different from “real life”. Historically, when I have done intervals outside, I intentionally route to a flat road to try to keep things as steady as possible. Is erg mode not just a more absolute version of that strategy? (Note - I am not asking that in a snarky manner, just trying to reframe the question a bit)

But, I think there is a massive difference for me mentally in erg mode vs non erg mode. I have done both a lot in Zwift. Mentally, the non-erg mode is definitely more taxing for me. Chasing the right gear/cadence combo can be tough, and when you throw in the climbing/descending, it gets really tough. But additionally, I find that I am ALWAYS too high with my power once the interval is done. 10 minutes at 270 watts on erg mode would be bang on 270. In non erg mode, it would probably be 275-280 for me. Perhaps that reveals something about my personality, right? I seem to think I am running behind in the interval, and if I see the reading go 271…274…270…268, then I am like oh crap and adjust. Then a few seconds later I will see 284 as the reading. Even telling myself this, I cannot calibrate my brain around it. I have found (data to back it up) that I am more accurate when the interval target is XX5 rather than XX0. My brain seems to accommodate that range better. This might be at least partially the reason that non-erg mode is tougher, but not all of it.

20

I don’t really buy the idea that it’s hard to adapt to riding outside after lots of erg mode. At least in my case it’s not true, I can get pretty close to target watts on feel alone. Although, is feel alone even that important anyway? Most of us have a cycle computer displaying our power, so not hard to calibrate feel with that as you go.

As others have said the big advantage of erg mode for me is being able to switch off mentally on long easy rides. I can even do things like catching up on emails which helps make the time even more productive.