smart trainer erg or resistance mode?

Satish Punna

Hey I just got a cycleops hammer 'smart trainer'- whats the best way to use it for intervals on trainerroad? Erg mode or resistance mode?  
I understand erg mode keeps the watts the same regardless of cadence.  What if you are feeling good and want to over-achieve a bit or if you aren't feeling all that great and want to under-achieve (gasp)? 

Brian Hagan

@Satish Punna I would recommend trying both.  I usually prefer Erg, but sometimes I am not feeling it just want to go by my own RPE.  I am not sure I have ever had that over achieving feeling.......

Also, in TrainerRoad, you can hit the + and - buttons if you want to turn it up a notch (or down in my case).

Al Truscott

I've been using Erg modes for a decade or more, first on a CompuTrainer, and last few years on my KICKR. While I very rarely will use the +/- buttons on Trainer Road as @Brian Hagan suggests, I do that primarily if I feel I have mismatched my FTP to the setup I'm using (road bike vs TT bike, pedals vs hub for power source, etc). I believe that the workouts have specific value. I don't like to go outside the range of 95-100% for FTP intervals, or 110-120% for VO2 intervals. If I simply can;t perform on a given day (which last year happened about 5% of the time), I just bag the workout, presuming that indicates I need a day off, as much for mental rest as physical.

The BIG advantage of ERG mode, IMO, is that it takes my conscious mind out of the equation. I can't fool myself into thinking I can get away with less than the prescribed work effort. I either work at the level I have programmed, or I have to stop. No in-betweens. And that provides a level of motivation which I can sometimes lack, if I let my conscious mind run the show. I can always come up with excuses why I need to go easier, and it would be too easy to give in to them were I in resistance mode. Also, it helps with keeping my cadence up. The design in erg means the the faster I pedal, the "easier" each pedal stroke will feel.

Rafe Armstrong

I would do whatever feels best to you.  I use an old computrainer and only use the handlebar mount controller, never any of the video stuff.  I prefer the resistance mode as it feels much more like riding on the road to me.  I have not graduated to Trainer road or Zwift or any other platform.  For most workouts I play music loudly and use an app called Rock My Run on iphone which will allow you to play various tracks of music that the app designers put together and you can control the cadence of the music. So if you want to ride at a specific cadence range you can set it there and use a combination of gears and/or computrainer resistance settings to get the power output you want and by speeding up or slowing down the cadence just a few RPM intraride, you can easily increase or decrease your watts to tweak the power output.  Very motivating.  Also by doing this you can alter the workout if you are feeling great or not so great.  It allows me to do something like the following which is one of my favorite type of workouts:
4x20min@upper Z3 and every 2 minutes spike watts up to upper Z4 for 30 sec then back to Z3; repeat to the end of 20 mins.  I do this just by increasing cadence of the music by "spinning the dial" on the app to speed it up which speeds me up and lets me also work a different cadence range for a short time.  Alternatively sometimes I keep the cadence the same and just shift a gear for the 30 sec. surge.  Rock my Run app is also great for running if you like running with music as you can set the cadence with which you want to run.  For me I usually have it at about 90 for steady running but if I am doing challenging intervals I will likely have it at 94-98 depending on the speed I am running.  

Satish Punna

Thanks for the input everyone!  I did a 3x10 at 90% workout yesterday using erg mode.  I had to increase the resistance during the warmup since I wanted a bit of ABP but for the intervals just stuck to the 90%.  I actually quite liked erg mode for the intervals - it gave me a chance to focus on my spin and cadence where I might have just stomped on the pedals to get through the set previously.   

The power reported by my hammer was about 10 watts higher than my P1 pedals though which is another issue that I will need to investigate.  RPE and HR seemed to agree more with the hammer but I may be biased there too....

Hammer:  https://connect.garmin.com/modern/activity/2271183412 
pedals: https://connect.garmin.com/modern/activity/2271185512

Rafe Armstrong

@Satish Punna I  think you will find variation across different power measuring devices as they measure the power in different ways and at different locations in the power chain.  However they are all very repeatable and accurate from day to day when compared against it's self.  My advise would be to chose one and use it day to day when planning your workout.  And if that happens to be the hammer then use that daily for workouts, but I would frequently assess it against the P1's and if you know they are always about 10 watts lower then you can compensate when you are riding outside or in a race.