The current study evaluated the validity of 3 commercially-available accelerometers to assess metabolic equivalent values (METs) during 12 activities.
Thirty-three men and thirty-two women were enrolled in this study. The subjects performed 5 nonlocomotive activities and 7 locomotive movements. The Douglas bag method was used to gather expired air. The subjects also wore 3 hip accelerometers, a Lifecorder uniaxial accelerometer (LC), and 2 triaxial accelerometers (ActivTracer, AT; Actimarker, AM).
For nonlocomotive activities, the LC largely underestimated METs for all activities (20.3%–55.6%) except for desk work. The AT overestimated METs for desk work (11.3%) and hanging clothes (11.7%), but underestimated for vacuuming (2.3%). The AM underestimated METs for all nonlocomotive activities (8.0%–19.4%) except for hanging clothes (overestimated by 16.7%). The AT and AM errors were significant, but much smaller than the LC errors (23.2% for desk work and –22.3 to –55.6% for the other activities). For locomotive movements, the 3 accelerometers significantly underestimated METs for all activities except for climbing down stairs.
We conclude that there were significant differences for most activities in 3 accelerometers. However, the AT, which uses separate equations for nonlocomotive and locomotive activities, was more accurate for nonlocomotive activities than the LC.
Hikihara is with the Faculty of Engineering, Chiba Institute of Technology, Narashino, Japan. Tanaka is with the Dept of Nutritional Science, National Institutes of Health and Nutrition, Tokyo, Japan. Ohkawara is with the Faculty of Informatics and Engineering, University of Electro-Communications, Chofu, Japan. Ishikawa-Takata is with the Dept of Nutritional Education, National Institutes of Health and Nutrition, Tokyo, Japan. Tabata is with the Faculty of Sport and Health Science, Ritsumeikan University, Kusatsu, Japan