ABSTRACT
This study demonstrates a novel data-driven method of summarising accelerometer data to profile physical activity in three diverse groups, compared with cut-point determined moderate-to-vigorous physical activity (MVPA). GGIR was used to generate average daily acceleration, intensity gradient, time in MVPA and MX metrics (acceleration above which the most active X-minutes accumulate) from wrist-worn accelerometer data from three datasets: office-workers (OW, N = 697), women with a history of post-gestational diabetes (PGD, N = 267) and adults with ≥1 chronic disease (CD, N = 1,325). Average acceleration and MVPA were lower in CD, but not PGD, relative to OW (−5.2 mg and −30.7 minutes, respectively, P < 0.001). Both PGD and CD had poorer intensity distributions than OW (P < 0.001). Application of a cut-point to the M30 showed 7%, 17% and 28%, of OW, PGD and CD, respectively, accumulated 30 minutes of brisk walking per day. Radar plots showed OW had higher overall activity than CD. The relatively poor intensity distribution of PGD, despite similar overall activity to OW, was due to accumulation of more light and less higher intensity activity. These data-driven methods identify aspects of activity that differ between groups, which may be missed by cut-point methods alone.
Abbreviations: CD: Adults with ≥1 chronic disease; mg: Milli-gravitational unit; MVPA: Moderate-to-vigorous physical activity; OW: Office workers; PGD: Women with a history of post-gestational diabetes; VPA: Vigorous physical activity
Acknowledgments
The authors thank all researchers, project staff and participants involved in the SMART Work and Life trial, BABYSTEPS (females with a previous diagnosis of gestational diabetes in pregnancy), CODEC (adults with type 2 diabetes), MAP (adults with multiple comorbidities) and PACES (adults 12 to 48 months post a coronary heart disease cardiac event diagnosis) trials for access to the data used herein. University of Leicester authors are supported by the NIHR Leicester Biomedical Research Centre, and the NIHR Applied Research Collaboration (ARC) East Midlands. The views expressed are those of the authors and not necessarily those of the NHS, NIHR, or Department of Health. The SMART Work and Life project is funded by the National Institute for Health Research Public Health Research programme (project number 16/41/04).The views expressed are those of the author(s) and not necessarily those of the NIHR or the Department of Health and Social Care.
Author contributions
NPD, AVR and TY planned the study. NPD completed the main analysis of the study, with contributions from AVR and BM. NPD prepared the first draft of the manuscript. All authors read, provided feedback and approved the final manuscript.
Disclosure statement
No potential conflict of interest was reported by the authors.
Supplementary material
Supplemental data for this article can be accessed online https://doi.org/10.1080/02640414.2020.1812202.