SRM Wattage on Trainer VS. On Road

A light bike doesn't replace good fitness.

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by 2002SaecoReplica

Rich_W wrote:Any insights or discussion would be appreciated.

Go outside!

I think I'd rather have a colonoscopy than ride 20 minute intervals on the trainier.

FWIW, I've put my powertap on the computrainer before and they're both within a watt or two of each other.
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by ty-ro

This past winter I did a lot of work on the trainer and rollers. It is tough to get the 2x20's in when you are indoors. It just feels like crap when you are working that hard and not going anywhere. Fans are ok, but your body knows that it is not moving and it feels odd. I struggle to find a spot where I can keep the power constant, whether it is a hill or the flats. That said, the rollers or trainer are the only place where you can really dial this in and keep it toally constant. It does hurt more than outside though.

As a newbie to training with power, I noticed this issue the first time I got on the rollers with the power meter. It kind of sucks!

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by frd

I partially disagree with saeco.
2x20' on the rollers are hard, that's sure, however once you get a little used it's great quality IMO (plus some good music helps a lot). It's hard to keep such a steady pace on the road because of terrain/etc...
Only caveat, when I was doing a lot of 2x20 on the rollers with the powermeter I had to almost ignore my "road" power zones and aim for lower wattages.

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by Dr.Dos

It's possible to stay in the target zones but it can be brutally hard mentally. There are people who have less problems with it but most racers I know hate the trainer. I can adapt to the rigors of indoor training to a certain degree (the psychological strain of not riding at all vs. suffering on the trainer).

I rarely do more than one hour on the trainer, getting a good TSS of 70-80 out of it which is more than enough during winter. I'd rather add another hour of running which at least gives me a taste of freedom in nature, a workout for the upper body, some aerobic fitness and another (virtual) TSS of 60.

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by skinnyClimberBoy

i have the same dilemna with my powertap, doing 300 watts indoors feels like 400 outdoors.

and im going hard but power is way lower.

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by pritchet74

Watts are watts. They feel harder indoors because riding the trainer sucks. :wink:
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by sakic

I found this a interesting read onthe subject. ... ining.html

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by aadamcycle

Yes wattage on a trainer dose feel diffrent than wattage on the road dunno exaclty why but I would say alot has to do with diffrence in cadence changes and actual just feel of the bike while doing either. When riding my trainer (1upusa) my lactic threshold is around 275 and while on the road this spring I was able to maintain 315-325 with the same PE. I would just have to say its the nature of a trainer get use to it, although in the future when they start making trainers that cost 2 or 3k and simulate the rode from a computer model perfectly (yes i know about computrainer) then thats when things change.
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by ovlov


Just pin on a number and go race!

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by Peith

It takes some time to get used to doing the long effort intervals on a trainer. Don't stress so much on hitting a home run everytime, just go by "alls you can do is alls you can do." Eventually (it took me about 2 months) your indoor and outdoor wattage will become more similar. Good luck!

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by UKpaul

Hi all.

Has anyone else had experienced this. My training bike is set up with a powertap hub. I use it to commute to work and out training. I have a nice 20 minute climb which I can ride up at 260 watts while my Heart rate was roughly about 155 - 160. I can also power up a 4 minute climb at around 350 watts.
Yet when I go on the turbo and try and do 300 watts for 3 minutes my heart rate shoots up way above 175 and I really struggle.
I can't understand why if its harder on the turbo then why aren't my watts showing a higher number?

Any ideas ?


merged, as there are many threads on this

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by Rick

I find very low correlation between anything on a turbo trainer or rollers and the road. I think it is a combination of "mechanical impedance" factors and psychological factors. Trainer/rollers are always much lower power numbers for me too.

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by stephenjames

Heat and the difference in inertia I believe are the biggest contributing factors to the differences you see between indoors and outdoors. The type of trainer you use changes this but as a XC racer I believe working on lumpy low inertia trainers helps prepare my pedal stroke for very steep climbs. Provided that trainer can produce enough load that is.

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