Getting ready for winter and some trainer work to increase FTP. Anyone else have a significant difference in power they can generate on the trainer versus real road riding? Even if I’m out by myself, I can generate higher wattage on the bike riding roads then I can on the trainer. For example, recent solo rides are from 195-205 avg. watts, 225 on last group ride, but I have an incredibly hard time averaging 175 on the trainer even for only a few minutes.
Last night, a 1 hour trainer spin averaged 135w. While I was enjoying football and not trying to pump out the watts, I should have been closer to 160-170 I’d think if I had been on the road. This has been consistent regardless of spring, summer, or fall, indoor trainer rides I can’t hold the same power as on the road, even for only a comparably few minutes.
Getting ready for winter and some trainer work to increase FTP. Anyone else have a significant difference in power they can generate on the trainer versus real road riding? Even if I’m out by myself, I can generate higher wattage on the bike riding roads then I can on the trainer. For example, recent solo rides are from 195-205 avg. watts, 225 on last group ride, but I have an incredibly hard time averaging 175 on the trainer even for only a few minutes.
Last night, a 1 hour trainer spin averaged 135w. While I was enjoying football and not trying to pump out the watts, I should have been closer to 160-170 I’d think if I had been on the road. This has been consistent regardless of spring, summer, or fall, indoor trainer rides I can’t hold the same power as on the road, even for only a comparably few minutes.
Anyone else experience this?
I can think of several reasons why the wattage is harder to maintain on the indoor trainer.
Motivation or the mental effect is the most obvious. How does your HR correlate with the watts on the trainer?
Outdoors there is also a cooling effect as you cut through the air. It is hard to simulate this cooling effect indoors unless you use and industrial grade fan, capable of simulating 25+ mph.
There is also the inertia of the indoor trainer. Very few trainers have large enough flywheels to simulate the momentum that you get when riding on the road (even without drafting). The Lemond Revolution and the discontinued Velodyne are exceptions, but still not quite like the road.
I experience the same drop in power. It’s confusing as watts are watts, but my legs can’t push the same power on the trainer. It’s not just an indoor mental thing.
I’m not an expert, but I was under the impression that indoor watts do not equal outdoor watts, and the best thing to do is to test FTP indoors and outdoors.
I might be an exception, but Indoors or outdoors doesnt affect my test results. For indoor testing I use a lab model computrainer and ride a.mrc course that is mostly rolling hills. My outdoor testing is primarily sprint/oly bike splits.
I use a powertap for both indoor and outdoor riding and base my results on that data.
FWIW, I’m pretty conscientious about my warm up protocol on the computrainer and it always matches my powertap within 2-3 watts.
I’m using the KK with the pro flywheel (extra weight).
Yes,** that’s another trainer with a large flywheel. **
It would be interesting to compare perceived exertion for the same wattage on various trainers with different size flywheels.
Just wanted to add that I have Kurt Kinetic Pro with the extra large flywheel as well as the Lemond Revolution. I personally prefer the Lemond. I find it much smoother, and I can generate more watts with less perceived exertion. Could it be that the direct drive mechanism results in a more consistent resistance curve compared to the roller mechanism, where resistance can be affected by the tightness of the wheel on the roller?
I agree with Donzo98.
I use a powertap pro+. My trainer is a KK road machine.
My outside FTP is 285-288W.
My inside FTP is 280W with equal rest/motivation/fitness and similar conditions (non-heated trainer room, windows open, 14 degrees Celsius, AND with a fan) and I still have a difference in FTP.
So I set up my trainer zones as per my indoor FTP and my outdoor zones as per my outdoor FTP.
I’m not an expert, but I was under the impression that indoor watts do not equal outdoor watts, and the best thing to do is to test FTP indoors and outdoors.
You’re pedaling either way. They are equal, as long as you keep everything else the same.
My advice… get used to those numbers and use them as your “indoor baseline”.
x2
There is way more to this than motivation and cooling. It feels like pedaling into the wind for the entire ride. When I ride indoors my legs start to feel like bricks and hurt in places that never hurt outside. There is no doubt spinning the trainer recruits muscles that aren’t used outdoors. You also don’t get microbreaks in the pedal stroke like you do outside. With enough Indoor training you can bring the two closer together but I think it will always be physiologically easier to pedal outside.
I also try to fit in some trainer rides during the summer so that I don’t lose too much trainer fitness.
I’m not an expert, but I was under the impression that indoor watts do not equal outdoor watts, and the best thing to do is to test FTP indoors and outdoors.
You’re pedaling either way. They are equal, as long as you keep everything else the same.
-Physiojoe
LOL that is like saying Apples and Oranges are the same as long as they are both Apples.
There is a few reasons for this, the biggest being cooling. Having a fan will help drop the exertion level as your body will not need to overwork itself to cool you down, this leads to higher wattages. I was a fitness subject for Gatorade a few years back when they were studying the effects of weather conditions on the human body during exercises. This included wind, humidity, and rain. When I did not have wind cooling me, my heart rate would jump at least 5bpm, upwards of 10. Humidity with no wind was the worst as your heart rate would climb slowly until you eventually would crack, even if the wattage was relatively low.
There is a few reasons for this, the biggest being cooling. Having a fan will help drop the exertion level as your body will not need to overwork itself to cool you down, this leads to higher wattages. I was a fitness subject for Gatorade a few years back when they were studying the effects of weather conditions on the human body during exercises. This included wind, humidity, and rain. When I did not have wind cooling me, my heart rate would jump at least 5bpm, upwards of 10. Humidity with no wind was the worst as your heart rate would climb slowly until you eventually would crack, even if the wattage was relatively low.
This is a very good point … against heart rate based training.
Watts are watts, heart rate is influenced by 100 things not connected to the actual training. If you sit in the sauna at 100 degrees celsius, your heart rate might read 100+, but your cycling won’t improve.
To the indoor thing, riding a trainer and riding outside differ mainly in two things:
Steady effort vs. micro bursts
Unsteady body position outdoors so you can involve leverage and more (!) muscles outdoor, indoor all work is done by the major cycling muscles
If you train 100% of your time on a trainer and then change on the road (poor you) your watts will be lower and everything will hurt on the next day. This applies the other way round as well of course.
What to do about it? Some options:
Turn off watts (or cover them) on the trainer and go by PE
Train on the trainer year round
Establishing a baseline and retesting when using the trainer only in winter is not helpful, your body adapts and you think you improve, but the only thing that improved was efficiency on the trainer. Some cookie-cut training plan companies live on that snake oil. “Our athletes gain an average of 23 Watts at threshold over the winter, while riding only 3 times for 45 minutes”. This is not a time efficient training plan, this is a fraud.
Agreed with others I found that amongst other things (like a big fan) the size of the flywheel makes a big difference. I used to have much lower power on my old turbo trainer with an 800g flywheel and the feel was very different to riding on the road (i.e. that sticky mud feeling). I now get much closer power numbers since I switched to a new turbo trainer with a much larger 2kg flywheel which gives it a more road-like feel. I can now hit the same numbers as outside but it just requires alot more mental focus and effort than when riding outdoors - I find this great mental training for time trials.
There is a few reasons for this, the biggest being cooling. Having a fan will help drop the exertion level as your body will not need to overwork itself to cool you down, this leads to higher wattages. I was a fitness subject for Gatorade a few years back when they were studying the effects of weather conditions on the human body during exercises. This included wind, humidity, and rain. When I did not have wind cooling me, my heart rate would jump at least 5bpm, upwards of 10. Humidity with no wind was the worst as your heart rate would climb slowly until you eventually would crack, even if the wattage was relatively low.
I’ve always struggled producing the same watts for an extended period indoors versus outdoors. I have read Alex’s blog and tried his suggestions, but the results don’t differ much. I struggle with these cooling comments because yesterday morning I did my usual threshold workout outdoors, at 35 degrees, the workout was no easier, and my results weren’t any better than last week riding at 70 degrees. If this cooling philosophy was true, wouldn’t I have pushed out more watts - my heart rate may have been slighty lower, but power didn’t go up because I was cooled better.
Andrew, thanks for saving the trouble as that was my next step, set up the trainer in the garage and do a set w/the doors open in the early a.m. chill. Lots of god stuff in Alex’ blog, but I just see a entirely different power range on the trainer vs. actual road not casually explained away by motivation, heat, etc. I appreciate that there are both sides of the fence, but I’ve found a few others w/the same experience as my n=1…