Accuracy of uploadable pedometers in laboratory, overground, and free-living conditions in young and older adults

• Published in: The international journal of behavioral nutrition and physical activity 2012-12, Vol.9 (1), p.143-143
• Main Authors: Dondzila, Christopher J, Swartz, Ann M, Miller, Nora E, Lenz, Elizabeth K, Strath, Scott J
• Format: Article
• Language: English
• Subjects: Accuracy; Adult; Adults; Aged; Aged, 80 and over; Behavior; Body Mass Index; Electronics industry; Evaluation; Exercise; Exercise Test - instrumentation; Fitness equipment; Gerontology; Health aspects; Humans; Legs; Methods; Middle Aged; Monitoring, Ambulatory - instrumentation; Monitoring, Ambulatory - methods; Motion sensor; Older people; Pedometers; Precision; Sensors; Speed; Step-counter; Surveys; Walking; Young Adult; Youth
• ISSN: 1479-5868; 1479-5868
• DOI: 10.1186/1479-5868-9-143

The purpose of this study was to examine the accuracy of uploadable pedometers to accurately count steps during treadmill (TM) and overground (OG) walking, and during a 24 hour monitoring period (24 hr) under free living conditions in young and older adults. One hundred and two participants (n=53 aged 20-49 yrs; n=49 aged 50-80 yrs) completed a TM protocol (53.6, 67.0, 80.4, 93.8, and 107.2 m/min, five minutes for each speed) and an OG walking protocol (self-determined "< normal", "normal", and "> normal" walking speeds) while wearing two waist-mounted uploadable pedometers (Omron HJ-720ITC [OM] and Kenz Lifecorder EX [LC]). Actual steps were manually tallied by a researcher. During the 24 hr period, participants wore a New Lifestyles-1000 (NL) pedometer (standard of care) attached to a belt at waist level over the midline of the left thigh, in addition to the LC on the belt over the midline of the right thigh. The following day, the same procedure was conducted, replacing the LC with the OM. One-sample t-tests were performed to compare measured and manually tallied steps during the TM and OG protocols, and between steps quantified by the NL with that of the OM and LC during the 24 hr period. Mean error step scores (MES, criterion - device) and 95% Limits of Agreement (LoA) were calculated. There were no significant differences between the OM and tallied steps for any of the TM speeds for either the young or older adult groups. The LC significantly underestimated steps for the young adult group during the 53.6 m/min TM speed (MES 31.4 [14.5, 48.3]) and during the OG < normal walking speed (MES 12.0 [0.9, 23.1] (p