turbo v road...33% difference

jimmies

I recently got a turbo trainer which is fluid and mag resistance and when I go at a good constant effort for the fist 15 mins I get to around 3 miles - this is at the lowest mag level.

Now when out on the road a fairly relaxed (perceived effort)pace, the first 15mins gets me around 4 miles - and this is taking into account a slight wind today and slowed down by traffic at junctions, etc.....

I also feel like the 15 mins on the turbo takes more out of me than the road, now I know that I get hotter on the turbo.....but during the first 15mins I'm only just starting sweat so I don't believe the extra heat is really making much difference at this timescale.

I'm guessing this is normal - but I'm quite surprised at the difference in effort and distance

Herbsman

No. Just no.

bigpikle

speeds and distances are totally irrelevant on the turbo vs the road - ignore them, and if you want to, just use the speeds/distance of your turbo rides to compare one ride to another, but even that isnt very reliable in reality unless you have very very very well controlled setups and environments to ride in.

Turbos also often feel much harder as there is simply no way to stop pedaling like you do on the road. You have MUCH more momentum on the road as well so even if you relax your pedaling for a moment you dont slow down like you do on your turbo. Unless you have a large and heavy flywheel for your turbo there is always a very big difference in feel and momentum. The lack of cooling also plays a part in making things often feel much harder indoors.

Dont worry about it and just get on and ride some good hard turbo sessions!

jimmies

Herbsman wrote:

No. Just no.

care to expand on this statement???

bigpikle

he means that even talking about comparing road vs turbo speeds and distances is pointless - he was just doing it in his usual style....

jimmies

Bigpikle,

I totally agree and I won't be paying attention/comparing to the numbers between the two.......I was just surprised at the distance difference, as this and the time riding are the only things you can directly compare between road and turbo.

bigpikle

and heart rate, power, cadence and RPE - things that actually matter in your sessions. Speed and distance are just random numbers derived from these things and depend on how your turbo was designed and how you set it up, hence the potentially huge differences.

jimmies

ok.....the only things I'm able to directly compare.. :oops:

Alex_Simmons/RST

jimmies wrote:

I'm guessing this is normal - but I'm quite surprised at the difference in effort and distance

viewtopic.php?p=17939190#p17939190

What would the difference have been if the road was 10% gradient and into a roaring headwind?

Mettan

Mines (budget magnetic turbo) the other way around - 50/11 on the turbo is considerably more comfortable than trying to push it out on the road... (admitedly, it's a fairly basic trainer...).

Alex_Simmons/RST

Mettan wrote:

Mines (budget magnetic turbo) the other way around - 50/11 on the turbo is considerably more comfortable than trying to push it out on the road... (admitedly, it's a fairly basic trainer...).

At the same power output?

jgsi

Mettan wrote:

Mines (budget magnetic turbo) the other way around - 50/11 on the turbo is considerably more comfortable than trying to push it out on the road... (admitedly, it's a fairly basic trainer...).

I think you need to slam more resistance on the turbo then, so it feels like the road...
if the turbo is too budget to do that , consider upgrading.

bahzob

You can use speed on turbos. In the absence of a power meter its an OK substitute to measure output as a progress measure along with any inputs like HR/RPE.

But its only useful to compare with other sessions on the exact same turbo in the same conditions and the latter can be hard to manage.

Some turbos are better than others, you get what you pay for. The Kurt Kinetic is good and is calibrated so that the power required for a given speed approximates power needed on the road. But its still finicky in terms of setup.

(IMO the above is one reason rollers are better than turbos. There are less variables in terms of set-up and using, so you can more reliably compare speed session vs session and measure progress as a result).

Alex_Simmons/RST

Another type of turbo trainer that will be more repeatable and consistent is the Lemond Revolution. By removing the rear tyre-roller interface altogether, you remove the biggest problem in achieving consistency.