Full Frontal Level/Gears

Scheduled to do my first full frontal on Sunday. I am looking for advice on setting the correct level and also thoughts on gear selection. I’ve read the articles on preparing for full frontal and erg vs level and seem to get conflicting direction on setting the level. One says 3-4, the other 0-2. Thoughts on this question and gear recommendations would be appreciated. I do realize I will be changing gears during the test, but there might be a strategy to help me to perform better.

Thanks in advance for comments and suggestions.

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Hard to answer and pretty personalized. I tend to shift my “level” around depending on where I am in the test. I go up to 5-6 for NM so I can mash on a big power curve for max Kw, but I probably go 2-3 elsewhere to bring the curve down so I’m not struggling with a power curve on the endurance efforts.

And like @JSampson and others have mentioned, I just put my head down and chew stem at the end, so couldn’t really tell you what I’m doing at that point.

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I usually do the 5-second test on level 3. I’ve done the 5 minutes test on level 3 and 2. And then the 20 minute test I do on 2. And then the 1 minute test on 2 or 3. You can switch it around any time you want during the test (I would only recommend it during the recovery sections, tho).

But, it will depend on your bike’s gearing, preferred cadence, and power levels.

I always recommend you do a few workouts in level mode to get a feel for your gearing. And then you can also do one of the Open series workouts and get to a power level you feel you can hold and then try out the different levels to see which ones feel better and allow you to hit the cadence you want. Otherwise, what inevitably tends to happen is you end up where your preferred cadence is somewhere in between gears.

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Thanks for the recommendation. I assume, as mentioned in the other response, you do this during recovery periods.

Good idea on utilizing the Open workouts to get a feel for both the level and the gear.

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I am taking a highly analytic approach to Full Frontal Gear Selection. While perhaps too revealing of my inner nerd, I thought I’d share.

I’m getting ready for my first Full Frontal tomorrow. As recommended, I did some open rides and experimented with level mode. What I really wanted was a chart that showed me power at various gearing combinations and cadence to help me sort out what gears (and cadence) I need to be in to be around my expected power (and how much I need to change cadence to go up or down in smallish increments). Because power numbers go wild when you’re changing cadence or shifting (and the flywheel isn’t a steady state), knowing the steady state numbers ahead of time seems like it will be helpful.

Because I couldn’t find any useful data, I did some experiments and collected my own.
(Perhaps the minions could publish something like this for the most popular trainers.)
My goal was to estimate a formula formula that expresses power as function of rear-wheel/cassette RPM at different trainer levels at steady state (i.e. the flywheel is at steady speed). Armed with the formula, anyone could put in their own gearing ratios to sort out the best gears for their power targets. Based on my abilities, I estimated the formula for Level 1 on the KICKR using data from riding 30 seconds in each gear at steady cadence and then measuring average power and cadence once the numbers calmed down. Assuming that power increases with the square of rear-wheel RPM (which fit my data best and I think is theoretically how the power curves work on the KICKR–but I’m not certain), here’s what I got for my KICKR in Level 1. Observing that Rear-Wheel RPM = Gear Ratio * Cadence,

Level 1 Steady State Watts = 0.0039 * (Gear Ratio * Cadence)^2 + 13

where Gear Ratio is simply the ratio of teeth on the chainwheel to teeth on the cog for the gear you’re in (e.g. if you’re in the 36 tooth chainwheel and 17 tooth cog, the gear ratio is 2.118). For the statistically inclined, the R^2 using that formula was 98%. Since I couldn’t hold a steady cadence in the really big gear ratios, I couldn’t expose my estimate to those. It would have been better if I could have.

Using that formula, I calculated a table for a couple different cadences that I hope to use to help me select gearing and cadence ranges for the various efforts in Full Frontal. Since small changes in cadence can cause pretty big changes in power (relative to my targets), I expect to change cadence to adjust for my ability as I go. But for that to work, I need to be in the right gear. Here are a couple tables showing power in different gear ratios for a 90 and 95 RPM cadence respectively.

image

image

Has anyone else done something like this? Could the minions help make it better?

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@AkaPete Yes - I did the calculations when I was training with a Fluid 2. I found a power curve for the trainer, calculated the speed of my wheel in different gear ratios and cadences and then matched it to the power curve. There is a calculator on the web to convert various gear combinations and cadence to speed:

Bike Calc

At the time I was new to indoor training and didn’t have a smart trainer yet. I found that I didn’t end up using the calculations during Full Frontal - I would just ride on RPE.

I now have the Kickr Core and while I have a rough idea of its power curve for various levels I haven’t done the math and don’t plan to because it it just easier to set your gear ratios and then experiment with levels using the Open 30 video a week or so before Full Frontal. I know what cadence I can hold and find the right level and then shift gears up or down or adjust cadence. Slight adjustments work best.

Hope that helps!

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Can I infer you just select a particular level and then adjust power levels via gearing? If so, it does seem simpler dealing with fewer variables.

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@dmgadry61 For my last full frontal I used different levels for each of the tests. The gearing actually remained fairly constant so that I could get a good chain line but I did shift once during the FTP test. The rest was changes to cadence:

NM was 39/14 @ 5
MAP was 39/14 @ 4
FTP was 39/14 +15 @ 3 with 100+ cadence
AC was a standing start at 39/14 @ 4

There are two threads you may want to check out - I Hate the 4DP and I Love the 4DP which will give you some tips on the test, etc. There is also a Breakfast with Boz podcast where Ian interviews Neal Henderson while his neighbor takes the 4DP test that I have listened to several times:

Breakfast With Boz: Understanding 4DP

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Levels are just a simulation of riding on a slope. So the higher the level, the steeper the slope and the more quickly power ramps up with cadence. Higher levels also have the effect of making the jumps between gears larger (bigger power difference).

So I keep the level setting low (1-3) and use my gearing to adjust cadence/power. It would be like doing the test outdoors on a very slight incline or into a slight headwind. I find that the higher levels can bog me down on sprints (as they would on a steeper slope outdoors). But it obviously depends on the resistance slope of your trainer. Some trainers are much stronger than others when it comes to realistic slope simulation.

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Second the recommendation of this particular podcast episode. I’d always wondered whether I was doing the NM test correctly. As it turns out, I wasn’t. After doing it the way Sir Neal describes in the podcast, I saw two benefits: my highest NM yet, and more challenging NM power targets in the workouts.

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Yes–Kinda–But. A single shift in the middle of the cassette causes a large change in wattage (40 watts or more in level 1, it’s even more at higher levels). In addition, the power will skyrocket if you shift to a harder gear while you get the flywheel up-to-speed before it settles down and will do the opposite if you shift into a lower gear. So if you don’t know ahead of time which gears to use for different steady state efforts, it will be hard to find the right gear during the test. Also, because the power shifts from gear to gear are large, as a practical matter you will have to manage many power adjustments (i.e. 20 or 30 watts–or more at higher levels) by changing cadence.

It seems like most people figure all this out by trial and error. And I’m sure that works fine. But it seems like better information about power by gear ratio and cadence would make it much easier for first timers to figure out the right gearing.

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