JMIR Publications

ABSTRACT

Background:

Despite advances in consumer wearable technology, there is a knowledge gap in the association between quantified metrices by wearable technology and cardiometabolic health.

Objective:

As the quantified metrices are likely correlated with each other, this study aimed to identify the groups of latent factors measured by an activity tracker, the Fitbit HR, and associate these factors to cross-sectional health outcomes measured at the time of monitored activity.

Methods:

Using exploratory factor analysis, we identified three latent factors measured by the Fitbit metrics on physical activity: 1) Elevated metabolic equivalent of tasks (METS) [calories burned per day, minutes per day spent fairly active in METS 3-6 and very active METS≥6 and activity calories] 2) Total Activity [steps per day, distance in kilometers per day and number of floors per day] and 3) Others.

Results:

Participants in the highest quartile of Elevated METS, who spent the most time in moderate to vigorous exercise, had significantly higher blood pressure, worse lipid profile and higher calcium score. Increased average activity, represented by Total Activity, was associated with favourable cardiovascular risk profile.

Conclusions:

These findings support the use of Total Activity, regardless of intensity, for exercise prescription and points toward the adverse cardiovascular impact of overexercise. Clinical Trial: ClinicalTrials.gov ID NCT02791152