Accelerometer-measured physical activity in mid-age Australian adults

• Published in: BMC public health Vol. 22; no. 1; pp. 1 - 1952
• Main Authors: Mielke, Gregore Iven, Burton, Nicola W, Brown, Wendy J
• Format: Journal Article
• Language: English
• Published: London BioMed Central Ltd 21.10.2022; BioMed Central; BMC
• Subjects: Accelerometer; Accelerometers; Adulthood; Adults; Age; Cohorts; Demographic aspects; Devices; Education; Evaluation; Exercise; Gender; GGIR; Gravity; Health aspects; Health surveillance; Mean; Middle aged persons; Physical activity; Physical activity monitor; Physical fitness; Physiological aspects; Research ethics; Sociodemographics; Values; Wrist; Australia
• ISSN: 1471-2458; 1471-2458
• DOI: 10.1186/s12889-022-14333-z

Abstract Background Raw data from accelerometers can provide valuable insights into specific attributes of physical activity, such as time spent in intensity-specific activity. The aim of this study was to describe physical activity assessed with raw data from triaxial wrist-worn accelerometers in mid-age Australian adults. Methods Data were from 700 mid-age adults living in Brisbane, Australia (mean age: 60.4; SD:7.1 years). Data from a non-dominant wrist worn triaxial accelerometer (Actigraph wGT3X-BT), expressed as acceleration in gravitational equivalent units (1  mg  = 0.001  g ), were used to estimate time spent in moderate-vigorous intensity physical activity (MVPA; >100 m g ) using different bout criteria (non-bouted, 1-, 5-, and 10-min bouts), and the proportion of participants who spent an average of at least one minute per day in vigorous physical activity. Results Mean acceleration was 23.2  mg (SD: 7.5) and did not vary by gender (men: 22.4; women: 23.7; p-value: 0.073) or education (p-value: 0.375). On average, mean acceleration was 10% (2.5 m g ) lower per decade of age from age 55y. The median durations in non-bouted, 1-min, 5-min and 10-min MVPA bouts were, respectively, 68 (25th -75th : 45–99), 26 (25th -75th : 12–46), 10 (25th -75th : 3–24) and 8 (25th -75th : 0–19) min/day. Around one third of the sample did at least one minute per day in vigorous intensity activities. Conclusion This population-based cohort provided a detailed description of physical activity based on raw data from accelerometers in mid-age adults in Australia. Such data can be used to investigate how different patterns and intensities of physical activity vary across the day/week and influence health outcomes.