W Guo; TJ Key; GK Reeves Accelerometer compared with questionnaire measures of physical activity in relation to body size and composition: a large cross-sectional analysis of UK Biobank. Journal Article In: BMJ, 2019. Abstract | Links | BibTeX | Tags: 3248, accelerometer, physical activity @article{Guo2019,
title = {Accelerometer compared with questionnaire measures of physical activity in relation to body size and composition: a large cross-sectional analysis of UK Biobank.},
author = {W Guo and TJ Key and GK Reeves },
url = {https://www.ncbi.nlm.nih.gov/pubmed/30700478},
year = {2019},
date = {2019-01-29},
journal = {BMJ},
abstract = {OBJECTIVES:
Previous studies of the association between physical activity and adiposity are largely based on physical activity and body mass index (BMI) from questionnaires, which are prone to inaccurate and biased reporting. We assessed the associations of accelerometer-measured and questionnaire-measured physical activity with BMI, waist circumference and body fat per cent measured by bioelectrical impedance and dual-energy X-ray absorptiometry (DXA).
DESIGN:
Cross-sectional analysis of UK Biobank participants.
SETTING:
UK Biobank assessment centres.
PARTICIPANTS:
78 947 UK Biobank participants (35 955 men and 42 992 women) aged 40-70 at recruitment, who had physical activity measured by both questionnaire and accelerometer.
MAIN OUTCOME MEASURES:
BMI, waist circumference and body fat per cent measured by bioelectrical impedance.
RESULTS:
Greater physical activity was associated with lower adiposity. Women in the top 10th of accelerometer-measured physical activity had a 4.8 (95% CI 4.6 to 5.0) kg/m2 lower BMI, 8.1% (95% CI 7.8% to 8.3%) lower body fat per cent and 11.9 (95% CI 11.4 to 12.4) cm lower waist circumference. Women in the top 10th of questionnaire-measured physical activity had a 2.5 (95% CI 2.3 to 2.7) kg/m2 lower BMI, 4.3% (95% CI 4.0% to 4.5%) lower body fat per cent and 6.4 (95% CI 5.9 to 6.9) cm lower waist circumference, compared with women in the bottom 10th. The patterns were similar in men and also similar to body fat per cent measured by DXA compared with impedance.
CONCLUSION:
Our findings of approximately twofold stronger associations between physical activity and adiposity with objectively measured than with self-reported physical activity emphasise the need to incorporate objective measures in future studies.},
keywords = {3248, accelerometer, physical activity},
pubstate = {published},
tppubtype = {article}
}
OBJECTIVES:
Previous studies of the association between physical activity and adiposity are largely based on physical activity and body mass index (BMI) from questionnaires, which are prone to inaccurate and biased reporting. We assessed the associations of accelerometer-measured and questionnaire-measured physical activity with BMI, waist circumference and body fat per cent measured by bioelectrical impedance and dual-energy X-ray absorptiometry (DXA).
DESIGN:
Cross-sectional analysis of UK Biobank participants.
SETTING:
UK Biobank assessment centres.
PARTICIPANTS:
78 947 UK Biobank participants (35 955 men and 42 992 women) aged 40-70 at recruitment, who had physical activity measured by both questionnaire and accelerometer.
MAIN OUTCOME MEASURES:
BMI, waist circumference and body fat per cent measured by bioelectrical impedance.
RESULTS:
Greater physical activity was associated with lower adiposity. Women in the top 10th of accelerometer-measured physical activity had a 4.8 (95% CI 4.6 to 5.0) kg/m2 lower BMI, 8.1% (95% CI 7.8% to 8.3%) lower body fat per cent and 11.9 (95% CI 11.4 to 12.4) cm lower waist circumference. Women in the top 10th of questionnaire-measured physical activity had a 2.5 (95% CI 2.3 to 2.7) kg/m2 lower BMI, 4.3% (95% CI 4.0% to 4.5%) lower body fat per cent and 6.4 (95% CI 5.9 to 6.9) cm lower waist circumference, compared with women in the bottom 10th. The patterns were similar in men and also similar to body fat per cent measured by DXA compared with impedance.
CONCLUSION:
Our findings of approximately twofold stronger associations between physical activity and adiposity with objectively measured than with self-reported physical activity emphasise the need to incorporate objective measures in future studies. |
Nicholas Wareham J Aiden Doherty Large Scale Population Assessment of Physical Activity Using Wrist Worn Accelerometers: The UK Biobank Study Journal Article In: PLOS ONE, 2017, (Aiden Doherty , Dan Jackson, Nils Hammerla, Thomas Plötz, Patrick Olivier, Malcolm H. Granat, Tom White, Vincent T. van Hees, Michael I. Trenell, Christoper G. Owen, Stephen J. Preece, Rob Gillions, Simon Sheard, Nicholas J. Wareham). Abstract | Links | BibTeX | Tags: 9126, accelerometer, featured, methodology, physical activity @article{ADoherty2017,
title = {Large Scale Population Assessment of Physical Activity Using Wrist Worn Accelerometers: The UK Biobank Study},
author = {Nicholas Wareham J Aiden Doherty},
url = {http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0169649},
year = {2017},
date = {2017-02-01},
journal = {PLOS ONE},
abstract = {Background
Physical activity has not been objectively measured in prospective cohorts with sufficiently large numbers to reliably detect associations with multiple health outcomes. Technological advances now make this possible. We describe the methods used to collect and analyse accelerometer measured physical activity in over 100,000 participants of the UK Biobank study, and report variation by age, sex, day, time of day, and season.
Methods
Participants were approached by email to wear a wrist-worn accelerometer for seven days that was posted to them. Physical activity information was extracted from 100Hz raw triaxial acceleration data after calibration, removal of gravity and sensor noise, and identification of wear / non-wear episodes. We report age- and sex-specific wear-time compliance and accelerometer measured physical activity, overall and by hour-of-day, week-weekend day and season.
Results 103,712 datasets were received (44.8% response), with a median wear-time of 6.9 days (IQR:6.5–7.0). 96,600 participants (93.3%) provided valid data for physical activity analyses. Vector magnitude, a proxy for overall physical activity, was 7.5% (2.35mg) lower per decade of age (Cohen’s d = 0.9). Women had a higher vector magnitude than men, apart from those aged 45-54yrs. There were major differences in vector magnitude by time of day (d = 0.66). Vector magnitude differences between week and weekend days (d = 0.12 for men},
note = {Aiden Doherty , Dan Jackson, Nils Hammerla, Thomas Plötz, Patrick Olivier, Malcolm H. Granat, Tom White, Vincent T. van Hees, Michael I. Trenell, Christoper G. Owen, Stephen J. Preece, Rob Gillions, Simon Sheard, Nicholas J. Wareham},
keywords = {9126, accelerometer, featured, methodology, physical activity},
pubstate = {published},
tppubtype = {article}
}
Background
Physical activity has not been objectively measured in prospective cohorts with sufficiently large numbers to reliably detect associations with multiple health outcomes. Technological advances now make this possible. We describe the methods used to collect and analyse accelerometer measured physical activity in over 100,000 participants of the UK Biobank study, and report variation by age, sex, day, time of day, and season.
Methods
Participants were approached by email to wear a wrist-worn accelerometer for seven days that was posted to them. Physical activity information was extracted from 100Hz raw triaxial acceleration data after calibration, removal of gravity and sensor noise, and identification of wear / non-wear episodes. We report age- and sex-specific wear-time compliance and accelerometer measured physical activity, overall and by hour-of-day, week-weekend day and season.
Results 103,712 datasets were received (44.8% response), with a median wear-time of 6.9 days (IQR:6.5–7.0). 96,600 participants (93.3%) provided valid data for physical activity analyses. Vector magnitude, a proxy for overall physical activity, was 7.5% (2.35mg) lower per decade of age (Cohen’s d = 0.9). Women had a higher vector magnitude than men, apart from those aged 45-54yrs. There were major differences in vector magnitude by time of day (d = 0.66). Vector magnitude differences between week and weekend days (d = 0.12 for men |
