Consumer Wearable Health and Fitness Technology in Cardiovascular Medicine: JACC State-of-the-Art Review

Abstract

The use of consumer wearable devices (CWDs) to track health and fitness has rapidly expanded over recent years because of advances in technology. The general population now has the capability to continuously track vital signs, exercise output, and advanced health metrics. Although understanding of basic health metrics may be intuitive (eg, peak heart rate), more complex metrics are derived from proprietary algorithms, differ among device manufacturers, and may not historically be common in clinical practice (eg, peak V˙O₂, exercise recovery scores). With the massive expansion of data collected at an individual patient level, careful interpretation is imperative. In this review, we critically analyze common health metrics provided by CWDs, describe common pitfalls in CWD interpretation, provide recommendations for the interpretation of abnormal results, present the utility of CWDs in exercise prescription, examine health disparities and inequities in CWD use and development, and present future directions for research and development.

Keywords: athlete; exercise; fitness; photoplethysmography; wearable device.

FIGURE 1. Basic Methodology of PPG

Schematic of a wrist-worn consumer wearable device (A) and basic methodology of photoplethysmography (PPG) for a consumer wearable device (B). PPG signals are integrated over time to derive common clinical metrics such as heart rate (C).

FIGURE 2. Common Factors Affecting HRV and Data Quality Checklist

Data quality checklist for interpretation of heart rate variability (HRV) results from consumer wearable devices and common factors leading to high baseline/increased HRV and low baseline/decreased HRV. *See Supplemental Table 1. PPG = photoplethysmography.

FIGURE 3. Waveform Analysis to Estimate Respiratory Rate From PPG and ECG

Diagram depicting natural physiological changes in photoplethysmography (PPG) (left) and electrocardiography (ECG) tracings (right) with normal respiration that can be utilized to estimate respiratory rate. Adapted with permission from Charlton et al.

FIGURE 4. Algorithm for Interpretation of Abnormal Testing from CWDs

Flowchart for the interpretation of abnormal consumer wearable device (CWD) health metrics (A) and checklist to assess for data quality from consumer wearable device health metrics (B). PPG = photoplethysmography.

FIGURE 5. Potential Clinical Applications for CWDs in Cardiovascular Health

Three potential applications for the use of consumer wearable devices (CWDs) (A) in general cardiovascular health and (B) in exercise prescription for cardiovascular disease.

FIGURE 5. Potential Clinical Applications for CWDs in Cardiovascular Health

Three potential applications for the use of consumer wearable devices (CWDs) (A) in general cardiovascular health and (B) in exercise prescription for cardiovascular disease.

CENTRAL ILLUSTRATION. Common Health Metrics Provided by Consumer Wearable Devices

Top left show common cardiac health metrics provided by consumer wearable devices, while top right highlights common extracardiac health metrics provided by consumer wearable devices. Clinical applications and future considerations are additionally presented. HRR = heart rate recovery; HRV = heart rate variability; SpO₂ = oxygen saturation; VO₂ = oxygen uptake.