If every athlete is individual, why does TR treat indoor training as if it will be the same RPE as outdoor training for every cyclist?

I cannot be the only cyclist who feels like indoor training is almost impossible next to outdoor training. I can do sweet spot intervals in my sleep, but the moment I try them indoors (with all the fans, cooling, and other strategies possible) it feels like I am doing threshold or harder. I know I am not the only one who feels this way and I know this is not something that only people at my FTP feel.

I truly do not understand why TR as a brand adheres to the philosophy that every athlete is individual, and yet there is no recognition/adjustment on the part of the software or otherwise that indoor training is simply not achievable for some of us.

Same bike and PM?

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Method, timing and location used to determine FTP could be useful as well as the gear info above.

Outside of that, the issue of inside vs outside with respect to TR has been mentioned for years. I can search to find related topics if that’s useful.


Sorry, but this almost certainly isn’t a TR thing. You say you have fans, but I’d hazard a guess they aren’t cutting it if you can’t match or do very close to outdoors. Do you have a Lasko or similar?

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Do you use Erg mode on the trainer? Or resistance mode?

I say all this because, as far as I’m aware indoor and outdoor training should feel the same. Obviously it can be significantly more mentally demanding for some users indoors, and as you’ve highlighted, cooling is a massive hurdle.

  • What would you like to see or suggest be done in the software to address this?

You mention a problem essentially boiling down to “Inside vs Outside FTP” (which I do believe is a worthwhile discussion), but don’t offer anything specific as a ‘fix’.


Not TR, but using my Kickr Snap on Zwift once, I had a massive calibration error and blew myself up about 5 mins into a race.
I went to the shed, took my PM off of my race bike, brought it back in and installed it on my turbo bike and bingo- problem solved.

That felt like exactly what you describe.

A rundown of your indoor and outdoor kit would help folks troubleshoot I reckon :grinning:

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Well, it seems there are differences apart from perceived exertion.

Though TR seems to suggest it’s more about the factors that impact perceived exertion:

Honestly, I was a bit baffled by these two statements in the TR blogpost:

I totally agree, that with the right care you can narrow the gap between indoor and outdoor. I also agree that the metabolic and muscular capabilities doesn’t change based on whether you’re riding indoor vs. outdoor.

But if the ability to express ones “highest average power you can sustain for approximately an hour, measured in watts” (or whatever definition we use) is compromised riding indoor, then I would say FTP is different indoor vs. outdoor. This also matches with the description in the Wattkg blogpost.

I’ve tried both, yes.

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I don’t have access to the full article, but it would be interesting to see how they controlled for cooling in the study.

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Fair enough.

I suppose there’s two potential solutions in my mind.

  1. provide two separate PL’s for Indoor and Outdoor, and let AT select appropriate workouts based on whether you choose outdoor or indoor

  2. keep trying changes to your setup to close the gap in rpe

You aren’t the only one. It started out that way for me, and over time I closed the gap until there really isn’t a gap anymore. Some of it was in my mind, and some of it was trainer setup. FWIW I’ve got a Kickr direct-drive and my number one choice these days is using Sim mode (RGT or Zwift) as that helps make inside like outside. That plus an InsideRide e-Motion. Again FWIW.

Practically speaking, I’d go with the lower (inside) FTP estimate, assuming you are mostly/exclusively training inside this time of year. If you do some outside riding, the TSS will be a little low, and if you train outside you can simply flex the power a bit higher. None of that should cause any practical issues other than some numbers being slightly off. Trying to maintain separate FTPs in my analytics wasn’t worth the time and effort, when I tried it.


Can you please expand upon why you feel this way?
TrainerRoad utilizes a number of tools to perceive and adjust to athlete’s individual difficulties and expressed fitness, so I want to make sure I’m addressing each of your concerns singularly.


It did seem like they attempted to control for temperature effects (I can’t judge whether the control for temperature effect was adequate)

However, the authors do engage in discussing potential reasons.

Firstly, they found no difference in air temperature and sweat rate between indoor and outdoor testing. As such, temperature did not seem to affect the results in this study.

Secondly, they did find a difference in self-selected cadence between the two test scenarios. Specifically, cadence was 5-6 RPM higher indoors compared to outdoors. This could indeed be a contributing factor, as studies have shown that elite riders perform better at their most efficient cadence.

Beyond this, it is probably too soon to suggest with certainty why indoor and outdoor power differs so considerably.

If they controlled air temp and sweat rate so as to match them indoor/outdoor, this still doesn’t necessarily make for an even playing field IMO.

We also need to know if airflow from the same rider’s outdoor rides were matched indoors.

If indoor airflow was insufficient, but temperature and sweat rate was the same as outdoors, then it’s completely logical that indoor power output would be lower.

To say it another way…I can ride in my garage in winter with 0°C temperatures with no fan, and sweat quite a lot at 220w. Or I could ride outside at 220w and sweat very little because of the superior airflow.

Yeah. I’m not sure air temperature is enough. It’s the air flow that provides the cooling.

I see they had the same sweat rate and air temp, but obviously there’s something missing there

This does sound like the same issue of different FTP for indoor vs outdoor, which has a feature request. I hope that can happen someday.

Yup, broadly speaking there are a range of reasons that… All FTP’s are not created equal ™ Chad McNeese :stuck_out_tongue:

I joke, but when you dig into that topic here, we get Inside vs Outside, but then add in multiple power meters and bike setups (TT vs Road vs MTB) that all may yield a different “Functional” FTP in that use case. We know that physiologically, we have one basic FTP with all else equal. But the reality in practice is that many variables impact what we can do in different environments and gear cases.

Some apps do address this in varying ways with options for multiple FTPs related to those variables. I know it’s a mine field and one TR is hesitant to take on, but I just don’t buy some of the claims that AT and AIFTPD have it covered. Maybe they do, but there’s not much shared to back that up vs the fact that at least some other thinkers on the topic are coming to different solutions.


Thats what the intensity buttons are for, if an individual finds a workout too hard they can adjust it down. You don’t need TR to tell you that; TR will subsequently adapt your plan though to that individual’s response.