Internal medicine

Metric (unit)

Blood pressure

Psychiatry

Engineering

Balance (ability)

Physical therapy

Psychological intervention

Operations management

Autonomic nervous system

Heart rate

mHealth

Autonomic function

Heart rate variability

Ambulatory

Medicine

Physical medicine and rehabilitation

Arrhythmia & Electrophysiology Review

The autonomic nervous system plays a major role in optimising function of the cardiovascular (CV) system, which in turn has important implications for CV health. Heart rate variability (HRV) is a measurable reflection of this balance between sympathetic and parasympathetic tone and has been used as a marker for cardiac status and predicting CV outcomes. Recently, the availability of commercially available heart rate (HR) monitoring systems has had important CV health implications and permits ambulatory CV monitoring on a scale not achievable with traditional cardiac diagnostics. The focus of the first part of this two-part review is to summarise the physiology of HRV and to describe available technologies for HRV monitoring. Part two will present HRV measures for assessing CV prognosis and athletic training.

Heart Rate Variability: An Old Metric with New Meaning in the Era of using mHealth Technologies for Health and Exercise Training Guidance. Part One: Physiology and Methods