Activ8 Physical Activity & Sleep Data Format

Data Formats for Different Applications

The Activ8 device offers a robust solution for gathering physical activity & sleep data in various useful formats. Activ8 offers summarized physical activity information utilizing advanced compression technology.

Furthermore, Activ8 facilitates the collection of prefiltered 1Hz data for up to 10 days, enabling real-world data collection in user settings. This capability expedites prototyping, fostering the development of innovative applications, particularly in medical, rehabilitation, sleep, and sports fields.

Finally the device allows the capture of raw 16-bit XYZ acceleration data at 50Hz for up to 7.5 hours, providing flexibility for varied data collection needs.

Activ8 docking station

Summarized Physical Activity Information

Upto 180-900 days of Summarized Activity Information

The 8MByte internal memory allows for storage of upto 900 days of 5 minute summarized physical activity information or 180 days of 1 minute time intervals, using our advanced & validated physical activity compression technology.

Advantages of the Summary Time Period

Data is internally sampled at a rate of 50Hz and subsequently condensed over predefined time intervals (5 minutes, 1 minute, 30 seconds, 15 seconds, 5 seconds, 1 second). Opting for a lengthier time period does not compromise the precision of the information; it still provides an exact account of the seconds the user spends in each activity category and energy level. While the precise number of transitions may not be known, a significant advantage lies in the ability to conduct prolonged measurements, obtaining a highly accurate overview of daily life while managing datafiles effectively—particularly pertinent for larger-scale studies.

Information in each Summarized Measurement Point

Each measurement point encompasses a date/timestamp, detailing the duration (in seconds) the user spent in each activity class and the corresponding energy expenditure. Additionally, it includes the count of steps, validated even for elderly individuals or those with fragile mobility. The number of sit-to-stand transitions is also incorporated, offering a comprehensive dataset for nuanced activity analysis.


Summarized physical activity information proves highly beneficial for extended recordings spanning multiple days to weeks. Even with the data compression, you retain a comprehensive and detailed perspective of daily life occurrences, all while ensuring optimal user comfort is maintained.

Prefilted 1Hz Physical Activity Data

Developing Innovative Applications

Through years of experience, we have recognized the robustness, versatility, and user-friendly nature of accessing the foundational features upon which Activ8 was built. This facilitates seamless experimentation for the creation of novel applications in diverse fields such as medical, rehabilitation, sleep, and sports.

Capture Up to 10 Days of Prefiltered 1Hz Data

The enhanced Activ8 enables the recording of up to 10 days of meticulously prefiltered 1Hz data, facilitating data collection in real user settings, such as their homes, rather than within a laboratory environment.

This capability expedites the prototyping process, bridging the gap between research and implementation. Swiftly transforming new logic and algorithms for specific conditions and interventions into custom, dedicated products becomes finally feasible.

The Activ8 platform, comprising a CE certified device and software applications such as the PC application or the Activ8 cloud environment, can serve as the foundation for these advancements, thereby saving significant time in development, testing and certification. This streamlined process of using existing and proven building blocks makes it possible to test and create new applications that directly benefit a wide variety of applications including rehabilitation and care at home.

Each Prefiltered Data Point Encompasses the Following Information

Every prefiltered data point is rich in detailed information, including a precise time and date stamp, activity classification, step count, transfer count, the angle relative to the Earth’s gravitational field, and the measured energy. This comprehensive dataset enhances the depth of analysis and provides a nuanced understanding of the recorded activities, contributing to more informed decision-making in various applications.

Raw Physical Activity Data

Activ8 is not designed for extended periods of high-resolution data collection. Alternative solutions are available for capturing detailed raw physical activity information for prolonged periods (like the Activ8 Pro Motion Logger). For more information on these options, please feel free to contact us. Nevertheless, it is feasible to capture raw 16-bit XYZ acceleration data at a rate of 50Hz for durations of up to 7.5 hours using Activ8.

Data Format Technical Specification

Summarized activity information

Physical activity data is recorded at a rate of 50Hz, subsequently condensed, and automatically categorized in the Activ8 tracker into six distinct activity classes across predefined time intervals. Simultaneously, the energy or physical movement intensity is differentiated into six corresponding energy classes aligned with the identified activity categories. All data is time/date stamped.

  • Time intervals:
    • 5 minutes
    • 1 minute
    • 30 seconds
    • 15 seconds
    • 5 seconds 1 second

Activ8 Activity Tracking Mode

Device wear position: upper leg

  • Validation:
    • Activity classification: validated (multiple medical research groups)
    • Energy expenditure: validated
  • Date / time stamp
  • Activity classes over time:
    • Non-wear
    • Sitting
    • Standing
    • Walking
    • Cycling
    • Running (high-intense sports)
  • Energy expenditure classes: in kCal or MET per activity class, average MET & total kCals.
  • Stride/Step count: count per time interval, validated (also for fragile walkers)
  • Sit to stand: count of sit to stand transitions per time interval

Sleep + Activity Tracking Mode

Device wear position: chest

  • Validation sleep classification: yes
  • Date / time stamp
  • Sleep / Activity classes over time:
    • Non-wear
    • Lying on the side (left or right)
    • Lying supine (back)
    • Lying prone (chest)
    • Upright
      • Low Intensity/Sedentary behaviour (sitting, standing with low intensity): energy based
      • Moderate Intensity (walking, cycling, etc.): energy based
      • High intensity (sports, running, etc.): energy based
  • Energy expenditure: in kCal or MET per sleep/activity class, average MET & total kCals.
  • Stride/Step count: count per time interval, validated (also for fragile walkers)
  • Lying to Sit: count lying to sit transitions per time interval

Pre-Filtered 1Hz Physical Activity/Sleep Data

  • Data format:
    • Date / time stamp (unixtime)
      • Angle average X, Y, Z
      • Angle forward (Zav)
      • Angle sideways (Xav)
      • Angle Xav
    • Energy: average energy of the last second
    • Periodic count: strides (one stride is 2 steps)
    • Event marker button
    • Orientation: summarized data class
  • Sample rate: 1Hz
  • Measurement duration: upto 10 days.

Raw Physical Activity Data

  • Data format
    • XYZ acceleration data (16-bit)
  • Sample rate: 50Hz
  • Measurement duration: upto 7.5 hours
Activ8 wearable activity & sleep sensor

Get started today

Are you curious about the capabilities of Activ8 wearable activity and sleep sensors for your project? Let's collaborate to create a customised solution that perfectly suits your requirements.


Get in touch, we will be happy to help!


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