title: Accelerometer thresholds: Accounting for body mass reduces discrepancies between measures of physical activity for individuals with overweight and obesity.
abstract: The objective of this study was to explore whether accelerometer thresholds that are adjusted to account for differences in body mass influence discrepancies between self-report and accelerometer-measured physical activity (PA) volume for individuals with overweight and obesity. We analyzed 6164 adults from the National Health and Nutrition Examination Survey between 2003-2006. Established accelerometer thresholds were adjusted to account for differences in body mass to produce a similar energy expenditure (EE) rate as individuals with normal weight. Moderate-, vigorous-, and moderate- to vigorous-intensity PA (MVPA) durations were measured using established and adjusted accelerometer thresholds and compared with self-report. Durations of self-report were longer than accelerometer-measured MVPA using established thresholds (normal weight: 57.8 ± 2.4 vs 9.0 ± 0.5 min/day, overweight: 56.1 ± 2.7 vs 7.4 ± 0.5 min/day, and obesity: 46.5 ± 2.2 vs 3.7 ± 0.3 min/day). Durations of subjective and objective PA were negatively associated with body mass index (BMI) (P < 0.05). Using adjusted thresholds increased MVPA durations, and reduced discrepancies between accelerometer and self-report measures for overweight and obese groups by 6.0 ± 0.3 min/day and 17.7 ± 0.8 min/day, respectively (P < 0.05). Using accelerometer thresholds that represent equal EE rates across BMI categories reduced the discrepancies between durations of subjective and objective PA for overweight and obese groups. However, accelerometer-measured PA generally remained shorter than durations of self-report within all BMI categories. Further research may be necessary to improve analytical approaches when using objective measures of PA for individuals with overweight or obesity.
authors.affiliation: School of Kinesiology and Health Science, York University, Toronto, ON M3J 1P3, Canada.|School of Kinesiology and Health Science, York University, Toronto, ON M3J 1P3, Canada.
authors.forename: Lilian
authors.initials: L
authors.lastname: Raiber
authors.affiliation: School of Kinesiology and Health Science, York University, Toronto, ON M3J 1P3, Canada.|School of Kinesiology and Health Science, York University, Toronto, ON M3J 1P3, Canada.
authors.forename: Rebecca A G
authors.initials: RA
authors.lastname: Christensen
authors.affiliation: School of Kinesiology and Health Science, York University, Toronto, ON M3J 1P3, Canada.|School of Kinesiology and Health Science, York University, Toronto, ON M3J 1P3, Canada.
authors.forename: Veronica K
authors.initials: VK
authors.lastname: Jamnik
authors.affiliation: School of Kinesiology and Health Science, York University, Toronto, ON M3J 1P3, Canada.|School of Kinesiology and Health Science, York University, Toronto, ON M3J 1P3, Canada.
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Kuk
mesh_terms: D056044:Actigraphy; D000328:Adult; D000465:Algorithms; D001481:Basal Metabolism; D015992:Body Mass Index; D001835:Body Weight; D004734:Energy Metabolism; D015444:Exercise; D005260:Female; D017408:Guidelines as Topic; D006293:Health Promotion; D000070497:Healthy Lifestyle; D006801:Humans; D008297:Male; D008954:Models, Biological; D009749:Nutrition Surveys; D009765:Obesity / Q000378:metabolism / Q000628:therapy*; D050177:Overweight / Q000378:metabolism / Q000628:therapy*; D005082:Physical Exertion; D015203:Reproducibility of Results; D057566:Self Report; D014481:United States
keywords: accelerometry; accélérométrie; activité physique; body mass index; indice de masse corporelle; intensity thresholds; physical activity; seuils d’intensité