Intensity Minutes from Imported Heart Rate Data

Dear Garmin Connect Product Team,

I would like to propose a narrowly scoped change to the way Intensity Minutes are calculated in Garmin Connect, based on a reproducible inconsistency in current behavior.

Background

Intensity Minutes are defined as a metric derived from heart rate intensity relative to user-specific thresholds. They do not depend on GPS, pace, power, or activity modality — only valid heart rate data over time.

Garmin Connect already imports and displays heart rate time-series data from third-party activities (such as Zwift) through supported integrations.

Observed Behavior

Currently:

  • Activities imported from Zwift include visible heart rate data

  • These activities do not generate Intensity Minutes

However, when the same ride is dual-recorded using a Garmin device:

  • Intensity Minutes are credited as expected

  • Those credited minutes persist even if the Garmin-recorded activity is later deleted

  • The remaining Zwift activity now reflects Intensity Minutes it could not generate independently

This behavior strongly suggests that Intensity Minutes calculation is gated by data source attribution, rather than by the presence or validity of heart rate data.

Problem Statement

From a user perspective, this creates a disconnect between:

  • The documented physiological basis of Intensity Minutes (heart rate)

  • Their actual computation, which appears to depend on whether the heart rate originated from a Garmin device rather than whether it meets physiological criteria

This leads to confusion, duplicate recording workflows, and uncertainty about whether Garmin Connect can be relied upon as the authoritative record of training load and health metrics.

Proposed Change

Allow Intensity Minutes to be calculated from imported activities that include valid heart rate time-series data, regardless of source, provided that:

  • The data meets existing quality thresholds

  • User heart rate zones and thresholds are available

  • The integration is explicitly authorized by the user

This change would not require exposing additional data externally, nor altering partner agreements. It simply aligns metric computation with the metric’s stated physiological basis.

Benefits

  • Restores internal consistency to the Intensity Minutes metric

  • Reduces the need for dual recording

  • Improves trust in Garmin Connect as a unified health and training log

  • Lowers support friction caused by “missing” Intensity Minutes

  • Better supports modern indoor training workflows

Closing

This proposal is intentionally narrow and metric-specific. It does not seek broader data openness, only consistency between how Intensity Minutes are defined and how they are calculated.

Thank you for your consideration.

Respectfully,
Michael

Top Replies

  • I would like to propose a narrowly scoped change to the way Intensity Minutes are calculated in Garmin Connect,

    Intensity minutes are not calculated in Garmin Connect. It is the device that…

All Replies

  • I would like to propose a narrowly scoped change to the way Intensity Minutes are calculated in Garmin Connect,

    Intensity minutes are not calculated in Garmin Connect. It is the device that calculates them. Therefore imported activities won't show any Intensity Minutes unless you wear your Garmin device.

    If your Garmin watch has troubles to detect the increased HR in the low power mode (which some users experience), then the fix is easy - either record the activity on the device (the best option), or just start HR broadcasting on it (it enables the full power mode of the HR sensor), or use one of the advanced Garmin's HRMs calculating IMs (that requires that you do not wear the Primary Wearable Device simultaneously, though).

    TBH, when using Zwift, the best solution is keeping Zwift and Connect completely isolated. Simply connect your smart trainer to your Garmin device, and record the activity with it. Keep Zwift disconnected from Garmin Connect. If you record the activity with your Garmin device, Connect does not need anything from Zwift for calculating the performance and fitness metrics.