ERG mode for VO2 max intervals?

Training
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Checking back in on this.

  • Yeah, this 2nd effort is just odd. The green line shows what TR should have sent to the trainer, but it clearly didn’t respond properly, like it did on all the other intervals. I tend to ignore these if they are one-offs, despite being annoying in the moment. Could still be worth submitting to TR support to see what they say.

  • As to the 286/293 value issue, that is also something that TR will need to review.

Otherwise (and repeating my prior comment), this really seems to have gone well. You look super stable on cadence and that let the trainer increase and decrease as instructed by the app. You really nailed the entry in particular with minimal peaks or changes to cadence. This is key and again, you nailed it.

Job well done! :smiley:

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I chatted with support, they were going to look into the 286/293 difference but thought it was a display error. Their answer for the lack of resistance on the clearing effort was trainer calibration.

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LOL, I don’t buy the calibration issue at all, unless you stopped right after that bad interval, calibrated and magically got to the results seen in the remainder of your workout. Color me more than skeptical on that claim, that seems like scapegoating.

As a long time ERG user, I’ve had similar intervals that failed to kick in entirely and others that held on too long. I attribute those to the ghosts in the machines and technology just failing randomly at times. It happens and is a more acceptable answer to me than blaming you or the machine for lack of “calibration” nonsense.

All that aside, what do you think of the experience overall? Happy with it or disappointed in any way?

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The ERG intervals or the TR support?

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:rofl:

I was asking about the workout & ERG experience mainly, but am happy to read about either/both :smiley:

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Well I feel that ERG intervals are a bit weird. If you fall below 85 rpm it will kick your butt with resistance…so you have to be in the low 90’s for it to feel right. Now that I only race MTB, always training at a cadence of 90+ doesnt do much for those 70 rpm grinds up steep terrain. So I will likely use resistance mode in the future.

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Yup, I totally agree and understand. I do a fair bit of low cadence work in ERG, but it is mostly Endurance level with some Tempo & SS otherwise. I also mixed in some sprints as launches from 60rpm thru 120 rpm for BMX start practices.

But ERG can sure bite hard in those harder interval efforts if you fall down even a little bit. So I think selecting RES for some or all of those types of efforts makes sense. As ever, adapting your training (to include trainer settings & use) to mimic your actual needs outside is worthwhile IMO. That “specificity” angle is not to be ignored. ERG like any other training tool has pros/cons, and can be mixed in to training if when it’s appropriate, or can be set aside entirely for those that don’t like it.

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and when TR looked into it they believe it was radio interference and the trainer didn’t receive the command to raise resistance from say 120W to 280W.

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That sure could be and makes far more sense than “calibration” mentioned above. Glitches with tech happen, and comms being a critical link in the chain could mean even a small blip leads to results like this. Again, totally legit and understandable to me.

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Fellow MTBr here… and curious about this. Won’t dropping to 70 rpm and getting the resistance kicked up not simulate that steep uphill grind?

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It seems much harder…almost unnatural.

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56

:+1: I’ve been saying that since day 1 and have posted this several times:

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That first impression never changed over 2 years of using erg, and I kept drinking the kool aid by telling myself a few different stories. Starting with Wahoo’s “ultimate way to train - with power!” claim.

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That’s because ERG mode applies resistance in a constant way so when you get to the “dead spot” in your pedal stroke you have to apply just as much torque to keep them turning as when the cranks are level. When grinding up a hill out of the saddle outside your speed is constantly fluctuating up and down.

The good news is this can be trained, I’ve done threshold and VO2 intervals at a variety of cadences as low as 50rpm to work on neuromuscular conditioning and have developed a much smoother pedal stroke.

Or you could cheat and put the bike in 53x11 on the trainer so the extra inertia helps you through the dead spots on your pedal stroke.

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Hmm maybe I’m not following, a smart trainer with a heavy flywheel like the Saris H3 has a more realistic road feel because it lacks the noticeable pedaling dead spot versus the older wheel-on trainers. The flywheel basically makes the dead spot largely disappear. Of course you can switch to a really low gear, to reduce the flywheel speed, and increase the dead spot affect (versus a big gear like 53x11). Also, are you suggesting training cadence in Erg?

In any case, here is what I find weird…

Outside the wind and terrain don’t work together to provide the same resistance regardless of cadence. Instead, I have to change cadence and torque and gearing to respond to the wind and terrain. It is more about who is driving the power, me or the machine.

Paraphrasing Wahoo’s Guide to Using Erg Mode support article:

Outside (or with level, resistance, sim modes) you are trying to meet the power targets, inside in Erg you are trying to meet a cadence target.

After two years of Erg I decided meeting the cadence target seemed like a wasted opportunity. To make training inside to be more like outside, I switched to Wahoo’s Level Mode and then a year ago switched to Sim Mode and I like that even better because it is closest to training outside.

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I love ERG mode for every type of TR workout. I’ve never felt that it seemed “weird” or “not like outside” or any of those things. :man_shrugging:t4:

Horses for courses :wink:

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60

Not trying to convince you to stop loving erg, rather, to provide balance to the discussion.

On vo2 and anaerobic work, the TR workout instructions don’t always match the Erg prescription. But TR defaults to Erg, can’t easily put a range in Erg, and therefore has to put a target on the workouts. Yes you can change intensity but its not alway practical.

Last night I did some outside 1-min anaerobic/vo2 efforts, these were prescribed as “Full Gas” and 120-175% to have something on my head unit. The goal was to go full gas on every interval, without regard to what I could do on the next interval.

First set:

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ended up 175%, 153%, and 153% which I initially paced based on my 2022 power curve, and turned out to be a conservative effort. Those hurt but were repeatable. The second set was full send and ended up at 202%, 143%, and 118% which was a better effort given the goal of the workout.

Without erg holding me back, that first interval of 2nd set was an all-time power PR for 1-minute, beating out the previous two from late 2016 and early 2017.

re: weird I both agree and disagree. An analogy. I had a blunt force trauma to my eye about 10 years ago, had to have cataract surgery. After a week or two my brain started to ignore the edge of the lens in my field of vision. It basically disappeared from my vision. But even now, if I look for it, the edge of the lens can be plainly seen in my field of vision. Its just that my brain choses to ignore it most of the time.

Erg is like that as well. Its clear in my erg-like outside rides, power and cadence and torque have a wider distribution versus on my Kickr. But the real-time power graphs look “the same” if the power standard deviation is the same. And its easy enough for the brain to ignore the difference. But the difference is real and can be clearly seen in torque/cadence data.

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61

As an add-on to my thoughts earlier, there’s also the mental component. Do a 5 minute or an 8 minute VO2 Max interval and Erg will hold you to the power, regardless of cadence, until you either reach the end of the interval or you fail. It’s helping you all the time, because you don"t have responsibility for metering the power. You just have to keep pedalling.

In Resistance mode, you have to do the work and modulate the power by manipulating torque, cadence and gearing. That’s (for me at least!) quite a different beast. Not necessarily harder, but definitely different - and much more like ‘real life’.

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Assuming a fixed power target like most TR workouts, RES is not that different from ERG as implied.

For a given RES/STD level, there will be a “wheel speed” on the trainer that gives a certain power level. Once you find the related gearing on the bike, along with your desired cadence, holding your power target in RES/STD is more about cadence than anything. This assumes you are shooting for a steady power, with a steady cadence and not changing through the interval.

In that way, it’s similar to what can be experienced in ERG, assuming you hold your cadence in a steady RPM. I feel that’s a practical assumption since it’s the same basic requirement in RES/STD, unless you are altering cadence along with gearing to hold the power target.

In all cases above, increasing or decreasing cadence will yield momentary changes in power up and down.

  • The key difference is that ERG acts a bit like a automatic transmission in a car (maybe even a CVT?) in that it will adjust the resistance level to hold the power target.

    • Drop your cadence without picking it up, the power level drops for a moment until the app/trainer increase relative resistance to attain the target power. Inverse for cadence increases.
    • This is all influenced by the lag in the trainer and app making changes to the resistance to hold the power target.

  • RES/STD will more simply result in higher or lower power in relation to cadence changes in the same direction (again, assuming no shifting is taking place on the bike).

    • Drop your cadence without picking it up, and you will be below power target until you increase cadence again. If your drop in cadence is intentional and you aim to hold target power, shifting is needed. Inverse for cadence increases.

So, unless we are talking about shifting mid-interval and assuming people shoot for the same power throughout, the basic focus once into the interval (regardless of the mode) is that cadence is largely the key to holding / providing the target power.

And outside of all that, I have still yet to see or hear about any studies comparing ERG to any other modes. I tend to believe we are talking less than marginal gains/losses here until someone can show that time in ERG is functionally different with respect to training adaptations.

  • I get all the “different” & “more like outside” thoughts, but do we actually know that makes one mode better/worse than the other WRT training results?

We do plenty of things in training that aren’t direct simulations of riding and racing outside. The pure nature of many interval training approaches are not “like outside”. Frequently, that is intentional and beneficial in many cases.

In that vein, I wonder if the actual trainer mode is either beneficial or worthless? It’s hard for me to believe that there is anything more than minor differences at play here either way, since there doesn’t seem to be anything more than speculation and bro-science at this time. Maybe it’s yet to be discovered / documented, but I welcome anything more than gut feel and anecdotes that seem to be the norm in these discussions.

Additionally, since RES/STD modes are effectively “fixed” in the sense that they are not dynamically changing in any way like we see for SIM mode (riding virtual terrain in apps like Zwift, RGT, Rouvy, FulGaz, etc.) these modes are also a step removed from “being like outside”.

  • RES mode is largely a linear increase in power vs speed, akin to the standard magnetic trainers of old. Not really like outside since wind resistance in particular is exponential relative to speed.

  • STD mode is more progressive with power vs speed, that is more like old fluid trainers which may aimed to mimic outside feel. From a speed to power/resistance perspective, this makes sense. But even with that similarity, it’s not dynamically changing.

As such, using either of those modes is more of a fixed / known scenario that can be easily and repeatedly applied with known gearing and cadence to hit a power. They lack the subtle variation we get outside from road pitch, wind, and even road surface changes that make holding a desired power target outside more tricky.

For anyone wanting to get closer to that, using SIM mode in those apps above makes the most sense. I know plenty of people here do at least some of their trainer work like that, including me with Z for many of my Z2 rides.

Many tools in the box, and I think they all get us to the same basic result. There may well be functional differences hiding there, but I’d love to actually see some data on true training outcomes to make that more clear.

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63

For me, I think it’s the mental disconnect. In ‘real life’ and Resistance Mode, if I’m riding along and my cadence drops, power will drop and keep dropping until I lift my cadence - all assuming torque is more or less constant (under my control).

In Erg, it my cadence drops, torque is ramped up by the trainer (not under my control) and power is more or less constant (within tolerances). That’s different.

I suspect different riders are differently sensitive to that difference, and also for each rider it matters more for some interval types and intensities than others.

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