SUF Support Tips: All about Level Mode

SUF Support Tips: All about Level Mode

Last week we touched on using ERG mode on a smart trainer, so this week, let’s have a look at Level mode and how it works! In Level mode, you will need to shift gears to meet the power targets. (Unlike ERG mode where the trainer meets the power targets for you)

Resistance Curves

Level mode applies a standard resistance curve to the trainer. The curve replicates outside riding- the faster you go, the greater the resistance. Outside, you get more wind resistance. If you’ve ever wondered why you are always riding in a headwind, this explains it. You’re just going that fast! So on a trainer, with a resistance curve, you will have a similar effect.

Each trainer will have different levels, each one will have a steeper curve, adding a greater amount of resistance with speed. There’s a great graph here of the power curves associated with the different levels for a Wahoo Kickr.

How do I decide what level to use?

The general answer to this is probably level 2 or level 3. But, how do you decide and why?

Depending on how strong you are, you’ll want to pick the one that gives you the best range to cover your recoveries as well as your max efforts.

Think of level mode as a slope on a hill. If the slope is too flat, you’ll get to the top (max out your gears) before you reach your maximum power. If the slope is too steep, you’ll struggle to keep up the effort for 20 minutes in your lowest gear. The steeper the slope, the greater the difference in resistance from one gear to the next. This will be important when you’re doing a fitness test and really want to be able to fine tune choosing the right gear for the right effort at your most comfortable cadence.

Most likely, it will take you a couple of tries with Level mode to figure out which one works best for you. Stronger riders will tend to need the higher levels (which have more difficult resistance curves) and weaker riders will need to use level 0 or 1 as the resistance is lower. Each trainer is different, so this is really just a starting point to finding the level that works best for you.

Most Sufferlandrians find Level Mode 0 through 3 sufficient for most workouts. If you’ve got a particularly high 5-second power, and you’re doing a session like Violator, you might need to choose a higher level for those kinds of sessions.

When should I use Level mode?

Level mode should be used when you’re trying to determine what you’re really capable of. You are the one in control of putting out the power! This is why Full Frontal should be done in Level Mode. The constrained effort in Half Monty needs to be done in Level mode also, as you adjust your power output based on your pre-determined heart rate constraints.

Every workout can be done in Level Mode if you choose! There are benefits to training in Level mode, just as there are benefits to using ERG mode. For more about that, check out this article:

Is ERG mode killing my training?

For more information on whether to choose ERG or Level mode for a particular workout, check out this article:


How do I select Level Mode on my trainer?

We’ve got you covered in this help article: ERG or Level Mode

Please don’t hesitate to leave any questions or comments below! You can start a help ticket if you want some help getting started.


THat’s an excellent graph - i can take the bottom left quarter of it now and blow it up for the relevant settings on the wall …

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This is fascinating… BUT would you mind providing access to the data or formulas for each line? (I guess I can try to find it for my trainer)

Here is my thought
What I really want to look at is, what level should I be on given my desired cadence for level mode workouts or specifically FF… This is, of course, dependent on my chain rings and rear cassette (and selection).
But if I were to try to optimize my setup for the 5 sec sprint, I would know that I want to have aligned gears, say big ring and 3rd smallest gear and then know that I want max out at 125 rpm, for example, where my estimated power output is approximately X watts.
What I would like to know is - Knowing those inputs, what level should I choose? It looks like this can be solved with a little math.
Repeat for MAP, FTP & AC tests.
My apologies if this is too geeked out.


Can somebody check my math and rationale on this?
Here is some quick math based on my bike setup. Were I on a Wahoo KICKR as graphed at the beginning of this post, this implies that…

Say I want to target 200 W and 97 rpm for FTP in my FF test -
If I ride on Level 0, I need a gear ratio that supports 18.5 mph, so my best gear selection is 36/15 or 52/21

Say I want to target 300 W and 93 rpm for MAP in my FF test -
If I ride on Level 1, I need a gear ratio that supports 20.5 mph, so my best gear selection is 52/19
If this math is correct, then the next step would be trying to choose the gear combination / level that gives nice drive chain alignment and enough flexibility to move up and down a gear or two.
Yes, in principle, one figures this out experimentally, but I am in no mental state to work on my ideal gear when I am giving it the all out FF effort!


What are the center and right columns showing?

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I’m not sure all Smart Trainers will meet the Power Targets when I’m maintaining the Cadence Targets with out shifting gears occasionally. Really trying to get my head around this level mode business.


I’m going to be honest with you (and I like maths and engineering), I found it far easier to just experiment with gearing on Open sessions so I learn what gear to be in for each 4DP segment, e.g. I need to shift the cassette up 7 times and shift to the large chainring for sprints.

What km/h is this? No idea. How many gear inches? No idea. Can’t say that these are particularly relevant metrics (for me) on a trainer.


@ChrisLeyen one thing to note is that inertial effects come in to play with sprints. The graph shown is for steady state where cadence is constant. For example, I can get over 1,000w in a pretty low gear if I ramp the cadence quickly. So you don’t need to find a level that necessarily gives a corresponding watts for the speed.

But that is only really for the 5s type sprints. Your logic for the rest (without looking doing the calcs to vakudate) looks sound. I also used a similar process to work out why in GOAT my power would fluctuate a bit (in ERG) for the highest wattage efforts if I didn’t move into a higher gear. Using the highest level in the graph you get an idea for the wattage ceiling for a given flywheel speed. Basically at 50rpm there wasn’t enough flywheel speed for the KICKR to reliably produce enough resistance.


I absolutely insist that Erg mode is best for Full Frontal.

I adjust the percentage up and down to vary power level. Without this I struggle to maintain a sensible power level during 5 and 20 minute efforts.

The shorter efforts I still do in level mode


Having a dumb trainer gives me no option but I feel that part of FF is the pacing element. Using Erg you are not learning how to adjust that intensity yourself (or even to mentally overcome any perceived difficulty).

FF is as much a mental test as a physical one. Just IMO, of course.


We don’t recommend doing Full Frontal in ERG mode. Being able to pace Full Frontal is definitely a skill though, so we do recommend that you do other workouts in Level mode also if you’re struggling with this. While using ERG mode can seem to make Full Frontal easier, it isn’t really a good measure of what you are truly capable of.


I’ve sent you a message. Please send us an email or start a support ticket if you’d like some help getting this figured out! You’re right, not every smart trainer is the same.

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That is too much math for me today! :laughing:

As others have said, it is easier to figure out by doing it rather than just relying on the numbers. If you’re struggling to figure out what level to use, send us a ticket! We will happily help you troubleshoot this to figure out what level is best for you. (without the math)


@MMCSS The center column is the result of little ring to cog gear ratios turned into mph based on the inputs above (tire size and rpm).
The right column is the same but with big ring to cog gear ratios turned into mph.

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@aerobrain Thanks for the thoughts… The last time I did FF, I found myself struggling to find the right gears for 5min and 20min. My numbers had improved so I thought I should increase a level. This went wrong went I was in the big ring looking for a smaller cog and then needing to shift to the small ring to fish for the right cog again. I don’t believe that this had a significant impact on my results, but I would rather just set myself in a good place for the test. Your experimentation approach is the right one for 5 min and 20 min because it doesn’t take that long in one of the Open vids. I am debating whether this is reasonably achievable with NM & AC - I can give it a shot. But I thought it would be interesting to understand the underlying math.


Seems on the right track but I don’t see where you convert to power. I did something similar when I had the CycleOps Fluid 2 since I didn’t have a power meter. I calculated speed based on gearing as you do above and then found the power curve formula for the Fluid 2 (y = 0.0115x3 - 0.0137x2 + 8.9788x). So you need to make the same calculations for your trainer and also adjust for each level. Now that I have a trainer that measures power I just do an open ride to find the combinations that work best.


@JSampson Yes - that is correct. I was using the chart presented by Therese (beginning of this thread) with levels for the Wahoo KICKR as an example. However, I do not have a Wahoo KICKR - my trainer is a CycleOps H2.So I would need to find those curves and target power to determine the ‘right’ level.
You stated the curve formula for the Fluid 2 - Is x mph and y Watts for that formula?
My understanding is that the H2 is based on the Fluid 2 but I don’t yet see how the levels would apply to that formula. It seems there would be one or more term changes.

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@ChrisLeyen thanks - didn’t realize that first column was rear cogs. Makes sense to me now.

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Yes - apologies - “y” is Power, and “x” is speed in MPH. CycleOps/Saris publishes a chart with the Fluid 2 curve but I found the formula above from a blog by the bike geek. I guess you could try contacting Saris to get the power curve details for the H2 at each level but since you can measure power via the trainer you could also discover the power curve via testing at different speeds and levels and then matching that to your gear speed calculations. I couldn’t do that with the Fluid 2 and didn’t have a separate power meter.

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