ERG mode single leg drills

I’m curious how folks using a smart trainer in ERG mode are performing single leg drills. I’m back in SSB1 again (1st time with a smart trainer) and while I haven’t come across them yet, I know a couple of these workouts have single leg drills (which I think I benefit from), but will these work with the trainer in ERG mode? It seems to me that as the cadence drops, load will increase forcing an even lower cadence until I stall out (or bring the other leg back in). Do you guys just switch to resistance mode for those drills?


I did some this morning, in ERG mode, no problems*.

The load should only keep increasing if you cant hit the numbers but ILTs are generally at a relatively low wattage so shouldn’t pose the issue.

*Disclaimer: this will obviously depend on your equipment and personal experience and abilities. This is just an N-1 reply.


I have decent luck with single-leg in ERG on my Kickr17. These are often done at lower resistance levels. I think my last ones were around 50-60% of FTP. I suspect it would be more difficult at levels 70% or above, but don’t remember if I have ever done them like that.

This is a recent workout. Look at the steps leading into the first work interval.

No issues here with my Vortex.

If you have a single sided power meter though that’s something that could pose a big problem.


it was mentioned in a recent podcast IIRC, I think they suggested changing the settings to cadence only so it didn’t pause during drills.

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The problem with a single sided power meter paired via PowerMatch is that the power will read as zero when using the right leg, and this will trigger the ERG mode to continually increase the Resistance to try to meet the Target.

In these cases, a user should switch into Resistance Mode before starting the Single Leg Drills :slight_smile:


I’m wondering what set-up people are running that gets them the ability to do ILT drills in ERG. For me, I typically have my P1 pedals control my Kickr, PowerMatch on, connected via ANT+ so I believe I am dual-side connected. But when I tried to do ILTs today in Goddard my cadence dropped out to zero which obviously sent me into death spiral. I tried to change to Resistance mode (after some struggle realizing the change had to be in my Kickr connection, not my P1s!), but cadence still dropped out and I couldn’t stay unclipped. For the remainder I stayed clipped in and tried to just turn off my non-working leg.

Is anyone running this same setup that has had success with single leg drills. Or does anyone have a different setup that they suggest I use? Thanks

  • I don’t believe that cadence alone (absence of the data during the workout) will lead to a death spiral. The cadence itself is not used in any of the training calculations, and will not directly affect the results. I bet that you can unpair cadence and still get the same exact results.

  • Cadence DOES matter in how you are driving the pedals and it’s direct impact on the speed of the trainer (what really matters in the calculations). If your cadence it very “lumpy”, like can happen with ILT, I expect ERG could become very difficult.

  • I do ILT in ERG without power match, and have reasonable results. Like any other use of ERG, you need to make sure to “stay on top of the gear” and keep the legs moving.

  • I suspect that it is far more like to experience problems with ERG in ILT drills, since there is more chance of irregularity in power input.

  • Remember that the resistance unit adjusts as a result of increases or decreases in “trainer speed”. The increased variability we are likely to see in ILT, will potentially lead to problems.

  • As a result, some people may have better results with Resistance or Standard modes.

I use erg mode and do single leg drills (left only power meter). I think I don’t get the death spiral because I have a separate cadence sensor. I also don’t unclip the leg I’m not using, which seems to work.