# Incorrect Normalized Power calculation in workout analysis? **URL:** \ **Category:** TrainerRoad Software\ **Tags:** bug\ **Created:** [January 17, 2020, 12:54pm UTC](https://www.trainerroad.com/forum/t/incorrect-normalized-power-calculation-in-workout-analysis/28087 "2020-01-17T12:54:59Z")\ **Posts on this page:** 1\ **Showing post:** 16
**Author:** ![bbarrera](https://sea2.discourse-cdn.com/trainerroad/forum/user_avatar/www.trainerroad.com/bbarrera/32/14734_2.png) [@bbarrera](https://www.trainerroad.com/forum/u/bbarrera)\ **Post date:** [January 18, 2020, 12:26am UTC](https://www.trainerroad.com/forum/t/incorrect-normalized-power-calculation-in-workout-analysis/28087/16 "2020-01-18T00:26:31Z")
> [@jpowers](#): > > The key characteristic is that the intensity is a nonlinear function of a continuously-measured quantity (heart rate or power). In both cases, IIRC, the nonlinearity of the intensity is based on the lactate response to a workload. Yes. I wrote a short post about Coggan’s derivation here: > [@Why does "Efficiency Factor" use normalized power and not average power?](https://www.trainerroad.com/forumt/why-does-efficiency-factor-use-normalized-power-and-not-average-power/27007/11): > > It’s a pretty close approximation of the area under a curve of work vs time (a more precise formula would an integral function that most applications do no support. note: excel, for example, does not support calculus functions). Using 5th, 6th, and 7th, etc. powers will provide greater accuracy Hey Bob, hope you are doing well. My understanding is that Coggan analyzed blood lactate response to power above first lactate threshold (the aerobic one, LT1): and determined the following… You should be able to search and download that paper. Interesting read. --- _[View the full topic](https://www.trainerroad.com/forum/t/incorrect-normalized-power-calculation-in-workout-analysis/28087)._