Originally Posted by hhnngg1

The accuracy of the TR numbers is very questionable. My Cycleops Fluid2 FTP came in 40 watts higher than my powertap FTP which is a huge difference. However, the precision on most trainers is very good. For my Fluid2, the precision is really, really good. Like reproducible to the 0.1mph if going by rear wheel speed for a given power.

However, I strongly disagree that this means you can't use TR meaningfully. It just means that you can't use your virtualpower for outdoor racing with a powermeter, nor should can you compare it to others on the interweb or off those charts that tell you that with a FTP of 350 you should be a semipro racer.

In fact, I have noticed NO difference in training with TR after getting the powermeter save for readjusting the FTP to a lower number. Thresholds are similarly painful, anaerobics are like death, and TSS scores are nearly identical since they depend on the FTP. In fact, I'd say that for the vast majority of folks who aren't going to rely on power data for racing and whom don't NEED power data for outdoor rides, you can completely skip the powermeter and just go with virtualpower on trainerroad.

Just don't see that 340FTP on virtualpower and think "wow I should go pro!" unless you really are killing all the local Cat1s in your area.


In response to all those posting above saying about how training with inaccurate virtualpower indoors will harm your outdoor riding - total bogus. The virtualpower will force you to ride harder, are more consistently on a trainer, and will IMPROVE your trainer quality workouts significantly. It's 10x better than just riding randomly on a trainer or even thinking you'll do like 2 x 20' @ threshold but not having the visual feedback of actually doing it. I did almost exclusively trainer work from Nov-Jan and on my first outdoor 55 mile ride with 6000ft of climbing with perhaps only one prior outside ride during that time of a measly 20miles flat, I had no problems with it. Indoor training with virtualpower on TR really works as long as your virtualpower was derived from the FTP tests on TR and not some made up imaginary number.

And having trained primarily with HR last year before going TR virtualpower late last year, in my experience, virtualpower >>> HR, mainly because I found that the fitter I got, the lower my HR would get despite increases in power. This becomes pretty evident if you export data to Golden Cheetah and look at your TRIMP score (weighted HR composite) - mine was decreasing despite going longer and with higher power in my workouts. I would have thought I was getting worse based on that HR number!