# \[DONE\] Horisontal line in trainingload

**URL:** <https://forum.intervals.icu/t/done-horisontal-line-in-trainingload/292>\
**Category:** Feature Requests\
**Created:** [23 January 2020 20:44 UTC](https://forum.intervals.icu/t/done-horisontal-line-in-trainingload/292 "2020-01-23T20:44:06Z")\
**Posts on this page:** 1\
**Showing post:** 9

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**Author:** ![david](https://forum.intervals.icu/user_avatar/forum.intervals.icu/david/32/30189_2.png) [@david](https://forum.intervals.icu/u/david)\
**Post date:** [26 January 2020 14:06 UTC](https://forum.intervals.icu/t/done-horisontal-line-in-trainingload/292/9 "2020-01-26T14:06:15Z")

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Its very much the standard Coggan stuff to calc CTL (fitness) and ATL (fatigue) except that I use TSB (form) = CTL - ATL whereas some other tools use TSB = CTL\_yesterday - ATL\_yesterday.

```
CTL_decay = exp(-1/42) (or whatever fitness days is set to)
ATL_decay = exp(-1/7) (or whatever fatigue days is set to)

CTL_today = CTL_yesterday * CTL_decay + training_load * (1 - CTL_decay)
ATL_today = ATL_yesterday * ATL_decay + training_load * (1 - ATL_decay)

```

Strava doesn’t track FTP over time which makes a mess of the fitness chart. So maybe its that? When I first built the fitness stuff I did compare to Strava and got identical results. Since then they have added in “relative effort” and I don’t know how that works.

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