Hi,
I don’t know which concept is the right one but Golden Cheetah’s description of Form (TSB) seams to be more logical at least for me: “Training Stress Balance/Stress Balance. It’s the result of subtracting yesterday’s Acute Training Load/Short Term Stress (“fatigue”) from yesterday’s Chronic Training Load/Long Term Stress (“fitness”)”
Either or is there a way to set Form as the day before value?
Thank you,
There isn’t an option to switch to yesterday’s data but I do have that on the todo list.
Any update on this? I to prefer to ser yesterdays TSB
@david According below sources form should be computed on yesterday ctl & yesterday atl:
(This is TSB details from the Joe Friel article you are referencing on the fitness feature itself)
What is the Performance Management Chart? | TrainingPeaks
=> " by subtracting yesterday’s Fatigue from yesterday’s Fitness we come up with the yellow line, or the Form"
I’m the guy who run Elevate (for strava & desktop app), I also implemented it as is.
Having it as an option could be great.
By the way, amazing work on intervals.icu 
!
Thanks 
When I started Intervals.icu it just seemed to be the right way to do it. Since then I have seen Elevate and GC and others that do it using yesterdays data. Hopefully I can get an option to switch implemented soon. Very busy with a bunch of much needed running related stuff right now.
Unfortunately not 
Intervals.icu mostly just stores CTL and ATL and calculates form when needed. So using yesterdays numbers for form today is a complication because yesterday’s data might not be easily accessible.
Ok understood. Will you work on it by the way?
Yes I will definitely sort it out (eventually). I am sure you know all about an endless todo list!
