The 5 Most Common Mistakes When Measuring HRV

And how you can avoid them!

Heart Rate Variability (HRV) is a crucial metric for understanding the physiological stress and the autonomic nervous system (ANS) responses, particularly the parasympathetic system. For researchers, getting HRV measurements right is vital to ensure high-quality and reliable data. However, several common mistakes compromise the accuracy of HRV analysis. Let’s look at these common pitfalls and how to avoid them!

1. Using Consumer Devices
It’s tempting to opt for consumer-grade devices, especially when working with tight budgets. But these devices often don’t meet the standards required for accurate HRV measurement inresearch. They’re typically designed for everyday users rather than professionals, and they don’t provide access to raw data—making it difficult to ensure data accuracy.

How to Avoid This Mistake: Stick with reputable, research-grade brands that specialize in providing raw data and meet the standards for scientific research. If you can’t access raw data or need to log into a portal to view results, you're likely dealing with a consumer-grade device. These devices aren’t suitable for high-quality, publishable research.



EcgMove 4 worn
2. Using PPG in Ambulatory Measurements
Photoplethysmography (PPG) sensors can be useful for short-term, stationary measurements in a controlled environment. However, when it comes to real-world, ambulatory measurements, PPG can be prone to inaccuracies. It struggles to provide precise beat detection, which is essential for accurate HRV calculations. Movement artefacts and noise are common in real-world conditions.

How to Avoid This Mistake: For more accurate HRV data, use an Electrocardiogram (ECG), which has a clear reference point (the R peak in the ECG signal) for detecting heartbeats. This method is far more reliable, especially in dynamic settings where a participant might be moving. Even research-grade PPG devices can struggle with accuracy in real-life situations, so ECG is generally a safer choice.

3. Using Devices That Only Record IBI or Have a Low Sampling Frequency
Not all ECG devices are equal! Some only record Inter-Beat Intervals (IBI), meaning you won’t have access to the raw signal data to check for artefacts. Additionally, devices that sample at low frequencies (under 1000Hz) compromise the accuracy and precision of HRV measurements.

How to Avoid This Mistake: Ensure that the ECG device you’re using has a sampling frequency over 1000Hz and captures more than just IBIs. This way, you’ll have access to high-resolution data that allows you to view artefacts and ensure the integrity of your HRV measurements. Low-quality data can lead to skewed results, which undermines the value of your research.

4. Not Having Access to Raw Data
Raw data is essential for ensuring accurate HRV measurements. Without it, you cannot identify artefacts, noise, or anomalies in your data that could distort your findings. Without access to the raw ECG signal, you’re flying blind when it comes to interpreting HRV.

How to Avoid This Mistake: Always ensure that your measurement devices provide access to raw data. If the device doesn’t allow you to view or download the raw signals, it’s not suitable for use in research. This step is crucial for identifying issues in the data that could impact the overall analysis and interpretation.

5. Using ECG in Isolation
Even with a high-quality ECG that records raw data at a high sampling rate, using it in isolation can lead to incomplete interpretations. HRV data, by itself, doesn’t provide the full context of what’s happening with the participant. Understanding how environmental or physical factors (such as movement, temperature, or barometric pressure) influence the data is essential for an accurate analysis.

How to Avoid This Mistake: Incorporate additional signals like accelerometer, gyrometric, barometric, and temperature data alongside the ECG. These contextual data points help researchers understand the circumstances under which the HRV measurements occurred, giving more insight into how the participant's body responded to different situations. Context is crucial for accurate interpretation of HRV results.

Click here to read more about the best ways to capture accurate HRV data

Skin Temperature Monitoring

New - Integrated IR sensor

Add skin temperature readings to the wide range of high quality signals captured by the Move 4 and EcgMove 4.

The IR sensor allows researchers to:

  • analyse individual circadian phases in the daily routine
  • monitor the increase of skin temperature fluctuation in sleep research
  • as a trigger for subjective data acquisition(questionnaires using Interactive Ambulatory Assessment)
  • Recommendations for skin temperatur monitoring



    IR Move 4

    New features that will amaze you in January 2024

    New sensor integrations and data transmissions.

    Customer requests and technical improvements are continuously taken up by movisens and incorporated into our products.

    • Accurately measure skin temperature! The Move 4 and EcgMove 4 are now available asstandard IR (infrared) versions. This enables the continuous acquisition of skin temperature in addition to the wide array of signals recorded.
    • View data in real time! Live-streaming of EDA data now possible with ourEdaMove 4.

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    Spriesender Pilz als Synonym für Neuerung

    SensorManager version 1.16.5 now available!

    New sensor firmware update

    movisens has released the new SensorManager version 1.16.5. This software release offers a firmware with the following changes:

    • Fixed state of charge for new battery generation
    • Fixed offset calibration of EdaMove
    • Added firmwares to measure skin temperature for Move 4 and EcgMove 4
    Install the latest version of the SensorManager and benefit from our improvements.

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    How does our heart behave under water?

    Cuore e Subacquea

    We're excited to support Giuseppe Di Tursi from Politecnico di Milano in his explorative research study "CUORE E SUBACQUEA" on cardiac physiology during immersion with our ECG sensors. This is the first study of its kind focused on assessing the feasibility to monitor the Electrocardiogram and Seismocardiogram (i.e. the measurement of chest’s vibrations induced by cardiac mechanical activity) during a diving session.
    The main goal and the innovation of this investigation stands in evaluating and quantifying the spontaneous adaptation of myocardial mechanics to the underwater environment.

    We're very excited about the upcoming results of this study and look forward to the further cooperation with Politecnico di Milano.

    ISAPA Move 4 Starter Set Winner

    As part of our ISAPA Break Session event, movisens held a Raffle to win a Move 4 Starter Set. Out of numerous participants we chose Merja Rantakokko from JAMK University in Finland as the winner!
    Congratulations!
    We wish Merja a lot of success with our Move 4 for her upcoming research work and look forward to reporting on her results in the near future.

    The meaning of Move 4 as Inertial measurement units (IMUs)

    Pervasive healthcare is among the most prominent fields of research with an increasing demand for IMUs.
    Inertial measurement units (IMUs) are electronic devices that typically consist of a 3-axis accelerometer (which measures linear acceleration) and a 3-axis gyroscope (which measures angular velocity).
    Typically, IMUs are used to track movement patterns or recognize activities of the user like gait analisis.

    The newly published paper (How We Found Our IMU: Guidelines to IMU Selection and a Comparison of Seven IMUs for Pervasive Healthcare Applications) shows that also in gait analysis the sensor Move 4 of movisens supplies outstanding results!

    IMU device specification of the Move 4

    Onboard Memory

    4GB

    Battery Capacity

    380mAh

    Max. Sampling Rate

    Max. sampling rate can be customized to 256 Hz

    Accelerometer Range

    ±16 g

    Gyroscope Range

    ±2000 deg/s

    Additional Sensors

    Barometer

    Temperature Sensor

    Ambient Light Sensor (LightMove 4)

    IR Sensor (Customizing: Integration of an IR temperature sensor)

    Respiration Sensor (Customizing: Integration of an respiration sensor)

    Charging Options

    Micro USB

    Additional Adaptor/Dock

    Waterproof

    IP64

    Developer Options

    Java API

    SensorManager Update

    The new SensorManager Update is now available!

    New Features:
    • Improved interoperability between sensor and movisensXS
    • Optimized readout of very long measurements
    • Usability improvements
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    Student Poject of the Year

    As part of movisens' 10th anniversary, the best student project is being awarded a prize for the student and the supervisor. You can now register for this competition with your student project. Every successfully completed student project can take part in the competition. This also applies to former students who have successfully completed a student project together with movisens in the past 10 years.

    Student Project of the Year