Jacobs Journal of Anatomy and Physiology

Validation of a Non-Transmitting Memory Belt for Measuring Heart Rate Variability

*Stefan Sammito
Department Of Cardiology, Otto-von-Guericke-University Of Magdeburg, Magdeburg, Germany

*Corresponding Author:
Stefan Sammito
Department Of Cardiology, Otto-von-Guericke-University Of Magdeburg, Magdeburg, Germany
Email:drsammito@web.de

Published on: 2018-07-18

Abstract

Purpose Validation of a non-transmitting memory belt (NTMB) for recording RR intervals and heart rate variability (HRV) under high exercise conditions. Methods 22 participants were tested on a bicycle ergometer (BE) and 14 on a treadmill ergometer (TE). The participants carried an NTMB (Suunto Memory Belt) as well as a mobile ECG system with wire-lead transmission (Schiller Holter MT-101). The rate of artefacts, the RR intervals and the HRV parameters were analysed. Results The NTMB showed no artefact at all, the Holter ECG had a low artefact rate of only 0.9%-1.6%. The mean difference of the RR intervals was 1.53±25.64 ms (BE) and 3.32±32.71 ms (TE) with a high degree of correlation (r=0.903-0.959) and a limit of agreement of -48.72 to 51.78 ms respective -60.79 to 67.43 ms. Comparison of both systems’ results showed differences in the HRV parameters. Conclusions This study confirms that an NTMB is suitable for recording RR intervals and the heart rate but not for HRV under high exercise conditions. A high degree of conformity with the Holter ECG system was revealed. Therefore, the NTMB is an acceptable alternative for use in scientific field trials if the Holter ECG or other heart rate monitors cannot be used.

Keywords

Heart rate determination, laboratory study, physical activity, ergometer, RR intervals

Introduction

Measuring physical activity is an established method for assessing physical strain. A correlation between cardiac output per minute and respiratory minute volume and the heart rate is known. Therefore, the latter measurement is also suitable to determine the individual load of physical activity, f.e. during work. The Holter ECG system with its wire-lead data transmission has been established as the gold standard for measuring the heart rate. In the last decade, an increasing number of heart rate monitors (HRM) have come into use which measure the heart rate via a chest belt and after wireless transmission store the data in a separate device, most commonly a wristwatch. Modern memory chip systems have made smaller both systems and enable more detailed measurements. Like the Holter monitor, modern HRMs record the time between two heartbeats (the beat-to-beat interval or RR interval) in a high sampling rate (e.g. 1000 Hz). So both measuring systems are also suitable to analyse the heart rate variability (HRV) by feeding the RR intervals into separate HRV analysis software. Several validation studies have demonstrated a high degree of correlation of heart rate measurements by the HRM and Holter ECG systems; in most of the studies HRMs from Polar® (Finland) were in the focus of validation.