Trying to figure out what happened, two different workouts, and unexpected results

So I did ‘Tabelon Law’, and got 45.62km, and an average power of 166 watts average earlier in the week. Just did ‘Baissey’, which looks like a harder ride, and got 30.65km, and 168 watts average.

Um, what happened? I see a 10kph drop in speed at somewhere about 4 or 5kph, and it stays at that level for the duration. The average speed shows a 10kph drop. The average power is 166w and 168 for today’s ride. The stats in Strava show it being a harder ride, and yet rules it a light ride. WTF!?!?

So, a harder workout on paper becomes a whiff? What happened? Did I miss something?

It’s on a Tacx Neo Smart 1st gen.

Thanks all…

Tabelon Law: TSS: 80, IF: .75 Cal: 906
Baissey: TSS 87, IF: .76, Cal: 916.

Less mileage on Baissey?

The “speed” measured by your trainer is basically made up.

If you do the exact same ride twice, with the exact same power, but once in low gearing and once in high gearing, it will say you went like >2x faster when you used the high gearing because the flywheel speed was faster.


:man_facepalming: :man_facepalming: :man_facepalming: :man_facepalming:

That’s what I did, I went to TSR, rather than TBR. Good grief. I was doing the same wattage, and it hurt a bit too, but I get docked for that? I didn’t think that was a thing with a ‘smart trainer’.


I guess. Totally not expected. I had to do over 38km for the yearly goal (per day), and thought I’d get more mileage. Guess it’s TBR (The Big Ring) for me from now on.

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For starters, here is the official doc from TR.

And as an FYI, TR now offers a “Virtual Speed” option.

That new Virtual Speed option works well from my use and that I’ve heard from others.

So the first ride was higher than is should be? Well, okay… But how is that happening during an ERG ride where the ‘speed’ is supposed to be controlled. I guess I don’t care, but knowing what the rule is, how it works, is important. I guess my scant use of TR is showing. (Does Zwift work the same way? I haven’t seen a difference)

I’ll see, ride the same ride tomorrow, TBR, and see if I get the inflated mileage. (I can use all the help I can get, big mileage to cover :hot_face:)

ERG is about controlling Power, not Speed/Distance. See the first article for the basic info on ERG & S/D with TR via the old ways. Fudging Speed/Distance is a pure connection to the gearing in use, no magic hiding there. Want big number… use big gears.

As to Zwift, it is a virtual method using your entered specs (weight, height, bike, wheels) and estimated values based upon your placement on their virtual roads.

TR’s new Virtual Speed/Distance is an uber-simplified version of the Zwift one. It’s the best option available in TR, so I suggest turning it on and just using those values vs fudging it with gearing choice in ERG. There are better reasons to be selective for ERG gearing that have nothing to do with estimated S/D data.

Is there a way to enable speed estimation post workout?

Not that I am aware.

Ignore the speed, it’s nonsense in ERG mode.


Lol yep. It’s why power and time spent riding are the more useful metrics on the trainer.

You could put it into the big ring and then have your trainer think you were riding at 50kph for your entire z2 workout, which would really maximize your ability to meet your “distance” goals.

As others have mentioned, TR does have an option to estimate distance now. And rides done in Zwift also do this too.

Its because you stopped pedalling at some point without pausing the app. Its a known bug with the strava virtual power settings.


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Nope. Ive asked the same question of support previously and theres no fix. They just need to fix the bug.

:flushed: There’s a bug? There’s always a bug. :wink:

I also misspoke, or perhaps didn’t: ‘speed’ did change, but power stayed the same. It threw me how they could all of a sudden diverge like that, and what I meant to say was ‘distance’ changed based on the calculated ‘speed’, but then that’s a bit redundant, right.

Somewhere something went sideways in a way I’ve never seen (or noticed) before. I had high hopes of finding a ‘secret sauce’ to get my year goal without spending 12/31 on the bike for hours like I did one year.

Yes, I DID change to TSR, and it did seem to be the same demand, as expected with ERG mode, and I did think about switching back, and DID towards the middle of the ride (and nothing changed). Perhaps more crucially, I DID take a few minutes off the bike, but I’ve stopped TR rides before for various and sundry reasons and not seen that effect (although usually not for that long). I guess I’ll try the same workout in TBR and see how it goes.

I keep forgetting that so much of this ‘simulated world’ is really just the output of some unknown algorithms and assume there is at least a tenuous connection to what we lazily call ‘reality’.

So distance and speed are calculated, ascent/descent are ignored, and power is either measured, calculated, or both. But it still beats riding out in 6 degree weather with 40mph (~64.4kph) wind gusts. (I wonder what the windchill would have been. How is it possible to dress for those conditions, WOW!)

Thanks everyone, most appreciated. And Merry Christmas, or not. Cheers to all…

So I enabled Virtual Speed and Distance, and deleted the ride in Strava, and reloaded it, and now all of the data is missing except for the main stats. Yikes… I should have downloaded the data from Strava, but the article made it sound so easy. I also only got a .fit file from TrainerRoad, as opposed to the .tcx file I was supposed to get. I should have left it alone…

As asked above, I don’t think the setting is retroactive to previous workouts. It will only affect you new workouts done with the setting turned on now.

Ahh, but it is retroactive. I waited and it finally re-synched with Strava, and my ‘distance’ jumped ~15km! The ‘speed’ also flattened. I no longer went from 30kph to 20kph, but stayed between 30 and 32kph. Interesting… I wonder how it might have affected previous rides. Hmm… Tomorrow is a holiday so maybe I’ll crunch numbers then.

Weird… In a calculated world, is there a reality? (That sounds too deep)

But it worked, or warped the past, or succeeded, or something. Interesting…

How to Get Virtual Speed Readings for a Past Ride

If you want Virtual Speed and Distance data for an old ride that was completed before Virtual Speed was enabled, you can get readings for this ride with a fresh sync to Strava! To get Virtual Speed readings in Strava for a ride that has already synced to Strava follow these steps


Oh, very interesting.

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Yes, but in the end it’s not metaphysics or quantum physics, it’s just juggling data differently. And possibly bug avoidance? If only we could do that with real life. But we just did! :flushed: :face_with_spiral_eyes: :smile: