I've been taking a coached, power-based cycling class (on Cycleops freewheel stationary bikes with Powertaps) for the last 3 months. After 1 month of base building, we tested our FTP, then did it again at the end of 3 months.

The raw data is interesting to me, but what mattered most was seeing an improvement over time. To me, that's the key. There may be a flaw in testing indoor vs. out, or 1 hr vs. a % of a shorter interval, but as long as you run the tests apples to apples, then you have a basis for judging improvement.

I test out at 3.4 w/kg. I'm hoping to both increase the numerator and decrease the denominator!

Susan