Sweat Loss Monitor

Samsung offers the Samsung Health Sensor SDK available for the Galaxy Watch running Wear OS. The SDK’s APIs allow a watch application to track various health sensor data based on a rich set of sensors that are supported by Galaxy Watch.
One of such data is the sweat loss after an exercise. To track other health sensor data, see Samsung Health Sensor SDK.


What is required to get the sweat loss value

In order to use the sweat loss measurement functionality, the following environment is required:

  • Galaxy Watch 4 series or later models, running Wear OS, powered by Samsung
  • Latest watch software version

Which APIs are used to measure the sweat loss

A watch application will use the following SDK and APIs mainly to calculate the sweat loss value:

  • Samsung Health Sensor SDK:
    • HealthTrackingService
      : connecting to the Health Tracking Service, obtaining a sweat loss tracker
    • HealthTracker
      : setting an event listener to receive the sweat loss value
  • Health Services:
    • ExerciseClient
      : a client for tracking a particular exercise parameters, in our case, steps per minute during running

Which data is used to calculate the sweat loss

The Samsung Health Sensor SDK calculates the sweat loss based on the following data:

  • User’s profile: Weight, height, age, gender
  • Exercise type: The Samsung Health Sensor SDK supports only the running exercise.
  • Processed data from the watch’s sensors: E.g. heart rate
  • Exercise data collected by Health Services
    : Steps per minute are fed to the HealthTracker to help calculate the accurate sweat loss amount.

The sweat loss can be assessed only when the following requirements are met:

  • Exercise duration: longer than 5 minutes
  • Running distance: longer than 2 kilometers
  • Sweat loss amount: 100 milliliters or greater.
  • Non-zero heart rate values during a workout: 80% or greater
  • Non-zero SPM (steps per minute) values during a workout: 80% or greater
  • SPM values during a workout: 110 or greater