title: Estimating Oxygen Uptake During Nonsteady-State Activities and Transitions Using Wearable Sensors.
abstract: In this paper, we present a method to estimate oxygen uptake ( VO2) during daily life activities and transitions between them. First, we automatically locate transitions between activities and periods of nonsteady-state VO2. Subsequently, we propose and compare activity-specific linear functions to model steady-state activities and transition-specific nonlinear functions to model nonsteady-state activities and transitions. We evaluate our approach in study data from 22 participants that wore a combined accelerometer and heart rate sensor while performing a wide range of activities (clustered into lying, sedentary, dynamic/household, walking, biking and running), including many transitions between intensities, thus resulting in nonsteady-state VO2. Indirect calorimetry was used in parallel to obtain VO2 reference. VO2 estimation error during transitions between sedentary, household and walking activities could be reduced by 16% on average using the proposed approach, compared to state of the art methods.
authors.forename: Marco
authors.initials: M
authors.lastname: Altini
authors.forename: Julien
authors.initials: J
authors.lastname: Penders
authors.forename: Oliver
authors.initials: O
authors.lastname: Amft
mesh_terms: D061725:Accelerometry / Q000379:methods*; D000328:Adult; D004734:Energy Metabolism / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D018670:Monitoring, Ambulatory / Q000379:methods*; D010100:Oxygen / Q000378:metabolism*; D010101:Oxygen Consumption / Q000502:physiology*; D012815:Signal Processing, Computer-Assisted; D016138:Walking / Q000502:physiology*
chemical_list: D010100:Oxygen