Validity of Wrist-Worn Activity Trackers for Estimating VO2max and Energy Expenditure

Abstract

Activity trackers are a simple and mostly low-priced method to capture physiological parameters. Despite the high number of wrist-worn devices, there is a lack of scientific validation. The purpose of this study was to assess whether the activity trackers represent a valid alternative to gold-standard methods in terms of estimating energy expenditure (EE) and maximum oxygen uptake (VO2max). Twenty-four healthy subjects participated in this study. In total, five commercially available wrist-worn devices were tested with regard to their validity of EE and/or VO2max. Estimated values were compared with indirect calorimetry. Validity of the activity trackers was determined by paired sample t-tests, mean absolute percentage errors (MAPE), Intraclass Correlation Coefficient, and Bland-Altman plots. Within the tested devices, differences in scattering in VO2max and EE could be observed. This results in a MAPE > 10% for all evaluations, except for the VO2max-estimation of the Garmin Forerunner 920XT (7.3%). The latter significantly underestimates the VO2max (t(23) = –2.37, p = 0.027), whereas the Garmin Vivosmart HR significantly overestimates the EE (t(23) = 2.44, p = 0.023). The tested devices did not show valid results concerning the estimation of VO2max and EE. Hence, the current wrist-worn activity trackers are most likely not accurate enough to be used for neither purposes in sports, nor in health care applications.

A New Fitness Test of Estimating VO2max in Well-Trained Rowing Athletes

“…Sartor et al (2013) have argued that many HR-based submaximal test programs are known to underestimate VO 2max because the workload is not high enough to promote adequate parasympathetic withdrawal and concomitant sympathetic activation. The tendency of underestimation was discovered in previous FFT-related studies (Anderson et al, 2019;Passler et al, 2019). Unlike those findings, this study found that the FFT method overestimated VO 2max in both the rowing and running programs.…”

“…However, these equations were developed for the nonathletic population and should be used with caution for well-trained athletes. The findings of this study revealed that the FFT method had a fairly accurate VO 2max estimation for well-trained rowers and paddlers and that the FFT method has been proven to accurately estimate VO 2max in nonathletic populations (college students, healthy adults, and recreational runners; Kraft and Roberts, 2017;Kraft and Dow, 2019;Passler et al, 2019). However, the rowing exercise program was not included.…”

“…The estimated VO 2max value is automatically generated after collecting heart rate (HR) data from a configurable test program (rowing or running) using Firstbeat sports software (Firstbeat, Jyvaskyla, Finland). Studies have revealed that the Firstbeat VO 2max estimation system is valid in nonathletic populations (Kraft and Roberts, 2017;Kyröläinen et al, 2018;Anderson et al, 2019;Passler et al, 2019). To the best of our knowledge, no study has reported the accuracy of this system in estimating VO 2max in well-trained athletes.…”

The Regulation of Fat Metabolism during Aerobic Exercise

“…VO 2max varies over a wide range among individuals, depending on level of aerobic training, genetic makeup, age, health status, and sex. It defines functional aerobic capacity of a single individual in a specific exercise performance and reflects a person’s cardiorespiratory fitness level [ 62 ].…”

Zur Reliabilität von Wearable Devices am Beispiel einer Premium Multisport-Smartwatch

“…Dass die aufgezeigte Konkordanzsituation der GF5 durchaus auch auf andere marktrelevante WD übertragbar ist, zeigen die aktuellen Daten von Passler et al (2019). Die in der vergleichenden Arbeit von Düking et al (2020) ermittelten und zum Teil durchaus ermutigenden linearen Befunde zur Validität ebensolcher WD sollten im Hinblick auf den hier explizierten Reliabilitätsaspekt der Konkordanz (aufgrund des abweichenden methodisch-analytischen Zuganges) in jedem Falle nicht hypothesenleitend verwendet werden.…”