Computed activity fields

[david]

Intervals.icu now supports custom activity fields either manually captured, computed using JavaScript code or read from FIT files. This is the first giant leap towards a programmable Intervals.icu!

You can click the play button to execute your script in the context of the selected activity to test.

The script has access to the following objects:

• activity: the activity being analysed
• athlete: for the activity
• streams: the power, heart rate and so on traces for the activity
• sportSettings: for the sport of the activity
• field: the field being evaluated
• icu: Provides access to other things loaded on demand

The icu object provides:

• wellness: for the day of the activity
• powerCurve (power duration curve)
• powerCurveFatigued0 (power curve after some KJ of work done)
• powerCurveFatigued1 (power curve after more KJ of work done)
• hrCurve (heart rate duration curve)
• paceCurve (distance vs time curve)
• gapCurve (distance vs time using gradient adjusted pace)

The last expression in the script is the value stored for the field. The script can also update many fields on the activity which are also saved (e.g. icu_training_load for a custom load calc).

{
  let v = .. custom training load calc ..
  activity.icu_training_load = v
  v
}

Variables are implicitly declared. Don’t use ‘let’ or ‘var’ etc… The scrips for all fields for an activity share the same sandbox this fails if they declare variables.

If you do need to declare things wrap the script in a block:

{
   let factor = 2
   activity.average_stride * factor
}

The JavaScript code runs in a sandbox on the server when the activity is analysed. If anyone figures out how to escape that sandbox I want to know first!

The data model is here:

Server side data model for scripts

This post lists the classes and enums available to JavaScript code running on the server (e.g. for custom activity fields with scripts). I am going to add more comments soon! Activity GapModel StravaGear Activity.Lap Interval Interval.Type IntervalGroup ZoneTime ZoneOrder IcuAchievement IcuAchievement.Type DataCurvePt HRRecovery Activity.Source HRLoadModel.Type PaceTssCalc.Type ActivityJsData ActivityStreamSet ActivityStream ActivityStream.Anomaly Athlete Athlete.WindSpeed Athlete.Rain Activit…

This post has more info on custom activity fields:

Custom activity fields

Intervals.icu now supports custom fields on activities. They are displayed with the activity summary, are available as columns on the activity list view and via the API (read and update). Click “Custom” under the activity timeline chart: [Screen Shot 2022-12-18 at 15.17.41] [Screen Shot 2022-12-18 at 15.18.15] [Screen Shot 2022-12-18 at 15.19.13] [Screen Shot 2022-12-18 at 15.18.51] The activity fields are per athlete. If you are coaching someone you can easily add your own to their li…

Similar functionality is available for interval fields:

Custom interval fields

Intervals.icu now supports custom fields for intervals. You can enter the values manually (e.g. from a test of some kind) or compute them using JavaScript code. Click “Fields” on the activity timeline page and then “Add Field” to create a new field or search for an existing field: [Screen Shot 2022-12-26 at 15.44.04] Note that the fields are specific to the athlete being edited. So if you are coaching people, create fields for yourself and then use the search button to add copies to your athl…

You can plot custom activity fields on the fitness and compare pages. If there are multiple activities on the same day then values are combined according to the aggregate setting on the description tab:

You can map custom activity fields to session fields from the FIT file:

Computed activity fields

You can now map custom activity fields to fields in messages in activity FIT files. This is where summary information about the activity is stored. The field is automatically populated with data from the FIT file if it is present. The default behaviour is to look in the session record for a matching field name or number. However you can prefix the field name/number with the name/number of the record to search in other records. [Screen Shot 2023-01-14 at 20.07.10] [Screen Shot 2023-01-14 at 2…

You can write scripts that directly process all the fit file messages:

Computed fields from fit file messages

You can now create custom activity and interval fields that process fit file messages with scripts. Tick the “Processes fit file messages” box: [Screenshot 2023-08-07 at 20.10.32] Your script will be run when the file is first processed or re-processed. Here is an example script that extracts heart rate monitor details from the device_info messages: { let hrm for (let di of icu.fit.device_info) { if (di.device_type?.value !== 120 /* HEART_RATE */) continue console.log("di " + di)…

Activity (and custom fields in general) can be converted before they are displayed. Fields with values in meters/second, meters and seconds are supported:

[Olly_Thomas]

This feels huge. Super impressive. Thanks for pushing this platform so much @david

Can’t wait to see the use cases people develop. Man I need to learn to code!

[John_Peters_endura.f]

This is awesome. Are computed field then available in a downloaded FIT file?

[MedTechCD]

And once again a new Playground
This is way more then expected and extends the possibilities by a giant leap.

[Benjamin_Hendler]

Hi! Amazing work! I’ve added a few public fields for measuring core temperature. Although, they work fine in the activity field creator window but does not return any value in the view for the workout.

[Inigo_Tolosa]

Definitively a game changing upgrade!!!
Many thanks.
@david I wonder if you plan to extend this to charts. It would be awesome to allow plotting processed data series (X, Y) in the current custom charts

[david]

I have documented the data model (sort of … needs more comments):

Server side data model for scripts

This post lists the classes and enums available to JavaScript code running on the server (e.g. for custom activity fields with scripts). I am going to add more comments soon! Activity GapModel StravaGear Activity.Lap Interval Interval.Type IntervalGroup ZoneTime ZoneOrder IcuAchievement IcuAchievement.Type DataCurvePt HRRecovery Activity.Source HRLoadModel.Type PaceTssCalc.Type ActivityStreamSet ActivityStream ActivityStream.Anomaly Athlete Athlete.WindSpeed Athlete.Rain ActivityType.Settings A…

[david]

@Inigo_Tolosa

I wonder if you plan to extend this to charts. It would be awesome to allow plotting processed data series (X, Y) in the current custom charts

Yes I am going to do that.

@Benjamin_Hendler

Although, they work fine in the activity field creator window but does not return any value in the view for the workout.

You need to re-analyse the activity to compute values for newly added fields. Did you do that?

@John_Peters_endura.f

Are computed field then available in a downloaded FIT file?

I just added that.

[Benjamin_Hendler]

@david

You

Yes, many times! No changes

[app4g]

@david

@John_Peters_endura.f

Are computed field then available in a downloaded FIT file?

I just added that.

Curious… these computed values in the FIT file, what are they stored as? Developer Fields?

[david]

Can you point me at one of your activities with core temp data so I can have a look. Tx.

@app4g

Curious… these computed values in the FIT file, what are they stored as? Developer Fields?

Yes developer fields. The name matches code of the field and they are float32’s or string’s.

[Benjamin_Hendler]

Can you check this activity? It seems like it does only calculate one of the custom fields. If I change the script to so it looks exactly like another one, the field will calculate that already has a “0” in it.

https://intervals.icu/activities/i8771586

[david]

Tx. I know whats wrong and am working on a fix. The scripts for an activity all run in the same sandbox instance so if you declare a variable with “let” and another script does the same, the 2nd script fails. You can workaround this by removing let:

temp_threshold = 38.4

Instead of: let temp_threshold = 38.4

[Benjamin_Hendler]

@Benjamin_Hendler

Intervals.icu

Great!! It solved all the metrics

[nich]

This is brilliant, thanks so much. I’ve added in running cadence (just a 2x of average_cadence) and running efficiency index (metres per minute per watt) as public.

Excited to see these added to fitness charts as well, I’ve actually been hacking the running efficiency index via wellness metrics

Also wondering – and this may already be true – will it be possible to write data to the stream as well? This would allow charting within the activity, which would be amazing.

[david]

Tx. I am going to be extending this to all parts of Intervals.icu including custom streams as soon as I can. I will be sorting out plotting custom activity fields on the fitness and compare pages today.

If anyone does want to declare stuff in the script wrap the body in a block:

{
   let factor = 2
   activity.average_stride * factor
}

[david]

This functionality has been extended to interval fields:

Custom interval fields

Intervals.icu now supports custom fields for intervals. You can enter the values manually (e.g. from a test of some kind) or compute them using JavaScript code. Click “Fields” on the activity timeline page and then “Add Field” to create a new field or search for an existing field: [Screen Shot 2022-12-26 at 15.44.04] Note that the fields are specific to the athlete being edited. So if you are coaching people, create fields for yourself and then use the search button to add copies to your athl…

[david]

You can now plot custom activity fields on the fitness and compare pages. If there are multiple activities on the same day then values are combined according to the aggregate setting on the description tab:

Choose sum, min, max or average.

[Matheus_Silva]

How can we add these custom fields in the fitness page? When I try to add a plot I can’t find any custom fields

[david]

They are showing up for me at the bottom of the list. Remember that if you are viewing another athlete you need to add your fields to them first by going to one of their activities, clicking “Custom” and using the search button.