FTP on turbo vs. road

andyeb

I did an FTP test on the turbo over the weekend - the 20 minute version where you take 5% off your average.

Despite being fairly well rested, the perceived exertion seemed much higher than I experience out on the road during fast training club rides.

I had a fan blasting away at me during the test on the turbo but it occurred to me there may be a large enough difference between my capability on the turbo and out on the road that training zones calculated from a turbo FTP test may be inaccurate enough to affect my training and pacing when out on the road.

I've read that there may be as much as a 10% difference, but it varies between individuals. Does anyone have a technique for quantifying this?

thanks,

Andrew

markhewitt1978

There isn't any definitive way to determine it, even pro riders have commented that their actual capable power on the road is somewhat higher than indoors. You're getting the same training benefit you just have to think of it as an indoor vs outdoor FTP.

maryka

Depends on a lot of things including what turbo you use, but mostly it's whether you ride the turbo or not a lot. Some people who turbo a lot find the opposite to you.

Have you done a test on the road? Do that, then do another test on the turbo where you settle in at the same watts you did for the road and see what happens. If you actually blow up (physically become unable to pedal at those watts anymore) then I'd use 2 different FTPs. If you can do the same watts but the PE is just higher than I hate to say it but just HTFU on the turbo then as it's the mental side not the physical that is making the difference.

Turbo workouts and testing can be made more bearable for less PE if you get a decent turbo that feels more like the road. Things like Zwift, Bkool, virtual Strava, even TrainerRoad can distract your mind from the endless pain of pedalling. Give those a try?

markwb79

andyeb wrote:

I did an FTP test on the turbo over the weekend - the 20 minute version where you take 5% off your average.

Despite being fairly well rested, the perceived exertion seemed much higher than I experience out on the road during fast training club rides.

I had a fan blasting away at me during the test on the turbo but it occurred to me there may be a large enough difference between my capability on the turbo and out on the road that training zones calculated from a turbo FTP test may be inaccurate enough to affect my training and pacing when out on the road.

I've read that there may be as much as a 10% difference, but it varies between individuals. Does anyone have a technique for quantifying this?

thanks,

Andrew

I had the same. mine was 10% lower on the turbo for sure.

Grill

My turbo power is lower than the road but I have a lot of friends who put out more on the turbo. As far as RPE is concerned, a fast club ride will never compare to a 20 minutes test. A 20 minutes TT would be closer.

BrandonA

The power I am able to sustain over a 20 minute period is higher indoors than out. I think for me this is because I am yet to find a piece of road where I can ride at a fairly consistent amount of power for 20 minutes, i.e. when outdoors sometimes you are going hard to get up a hill and then easy on the way down. On my Kickr, I program a certain wattage and then stick to it for a specified amount of time.

To answer the actual question which was "Does anyone have a technique for quantifying this?", I think this is fairly easy. You do two FTP tests, one outdoors and one indoors.

I also wonder how good people's fans are. Mine is very good and with the windows open I don't think I am losing that much energy (and therefore power) cooling my body.

Alex_Simmons/RST

For reference:
http://alex-cycle.blogspot.com.au/2009/ ... ining.html

cdrewery

Interesting article - just shows how important cooling is!!

philbar72

I put out a fair few more on the turbo compared to the road, and that is because I'm lazy.

markhewitt1978

philbar72 wrote:

I put out a fair few more on the turbo compared to the road, and that is because I'm lazy.

It always surprises me that as a bunch who are interested in fitness and take part in fitness activities regularly just how lazy most of us are, and I include myself in that. We're prepared to go and ride 60 miles but put in an effort up that hill? Nah, can't be arsed.

aberdeenal

markhewitt1978 wrote:

philbar72 wrote:

I put out a fair few more on the turbo compared to the road, and that is because I'm lazy.

It always surprises me that as a bunch who are interested in fitness and take part in fitness activities regularly just how lazy most of us are, and I include myself in that. We're prepared to go and ride 60 miles but put in an effort up that hill? Nah, can't be arsed.

Glad I'm not the only one in that club :oops:

giropaul

AberdeenAl wrote:

markhewitt1978 wrote:

philbar72 wrote:

I put out a fair few more on the turbo compared to the road, and that is because I'm lazy.

It always surprises me that as a bunch who are interested in fitness and take part in fitness activities regularly just how lazy most of us are, and I include myself in that. We're prepared to go and ride 60 miles but put in an effort up that hill? Nah, can't be arsed.

Glad I'm not the only one in that club :oops:[/quote

Believe it or not, cycling can just be an enjoyable experience in its own right. The neo- craze for data, " training" , objectives etc is maybe a result of the game-boy generation, but many of us were just riding bikes, even racing, just for the sheer unadulterated fun of it, taking it easy to admire a view, rather than gaze at a Garmin like an arcade game.