TY  - JOUR
PY  - 2018//
TI  - Validation of gait characteristics extracted from raw accelerometry during walking against measures of physical function, mobility, fatigability, and fitness
JO  - Journals of gerontology. Series A: Biological sciences and medical sciences
A1  - Urbanek, Jacek K.
A1  - Zipunnikov, Vadim
A1  - Harris, Tamara
A1  - Crainiceanu, Ciprian
A1  - Harezlak, Jaroslaw
A1  - Glynn, Nancy W.
SP  - 676
EP  - 681
VL  - 73
IS  - 5
N2  - BACKGROUND: Data collected by wearable accelerometry devices can be used to identify periods of sustained harmonic walking. This report aims to establish whether the features of walking identified in the laboratory and free-living environments are associated with each other as well as measures of physical function, mobility, fatigability, and fitness. <br><br>METHODS: Fifty-one older adults (mean age 78.31) enrolled in the Developmental Epidemiologic Cohort Study were included in the analyses. The study included an "in-the-lab" component as well as 7 days of monitoring "in-the-wild" (free-living). Participants were equipped with hip-worn Actigraph GT3X+ activity monitors, which collect raw accelerometry data. We applied a walking identification algorithm and defined features of walking, including participant-specific walking acceleration and cadence. The association between these walking features and physical function, mobility, fatigability, and fitness was quantified using linear regression analysis. <br><br>RESULTS: Acceleration and cadence estimated from "in-the-lab" and "in-the-wild" data were significantly associated with each other (p < 0.05). However, walking acceleration "in-the-lab" were on average 96% higher than "in-the-wild", whereas cadence "in-the-lab" was on average 20% higher than "in-the-wild". Acceleration and cadence were associated with measures of physical function, mobility, fatigability, and fitness (p < 0.05) in both "in-the-lab" and "in-the-wild" settings. Additionally, "in-the-wild" daily walking time was associated with fitness (p < 0.05). <br><br>CONCLUSIONS: The quantitative difference in proposed walking features indicates that participants may over-perform when observed "in-the-lab". Also, proposed features of walking were significantly associated with measures of physical function, mobility, fatigability, and fitness, which provides evidence of convergent validity.<p />  <p>Language: en</p>
LA  - en
SN  - 1079-5006
UR  - http://dx.doi.org/10.1093/gerona/glx174
ID  - ref1
ER  -