title: Objective Estimates of Physical Activity and Sedentary Time among Young Adults.
abstract: Background. This study examines factors associated with physical activity (PA) and sedentary behaviors (SB) in young adults (18-35 years) and compares objective and subjective assessment measures of PA and SB.Methods. 595 young adults (27.7 ± 4.4 years; 25.5 ± 2.6 kg/m2) enrolled in the Study of Novel Approaches to Weight Gain Prevention (SNAP) trial. Hours/day spent in SB (<1.5 METs) and minutes/week spent in bout-related moderate-to-vigorous intensity PA (MVPA; ≥3 METs and ≥10 min) were assessed using self-report and objective measures. Demographic factors associated with SB and MVPA were also explored (i.e., age, gender, BMI, ethnicity, work and relationship status, and number of children).Results. Objective MVPA (263 ± 246 min/wk) was greater than self-report estimates (208 ± 198 min/wk;p< 0.001) and differed by 156 ± 198 min/wk at the individual level (i.e., the absolute difference). Females, overweight participants, African Americans, and those with children participated in the least amount of MVPA. Objective estimates of SB (9.1 ± 1.8 hr/day; 64.5% of wear time) were lower than subjective estimates (10.1 ± 3.5 hr/day;p< 0.001), differing by 2.6 ± 2.5 hr/day for each participant.Conclusion. Young adults interested in weight gain prevention engage in both high levels of MVPA and SB, with participants self-reporting fewer MVPA minutes and more SB compared to objective estimates. This study is registered at ClinicalTrials.gov (NCT01183689).
authors.affiliation: Brown University and The Miriam Hospital's Weight Control and Diabetes Research Center, Providence, RI, USA.
authors.forename: Jessica L
authors.identifier: 0000-0002-6807-9515
authors.initials: JL
authors.lastname: Unick
authors.affiliation: Wake Forest School of Medicine, Winston-Salem, NC, USA.
authors.forename: Wei
authors.initials: W
authors.lastname: Lang
authors.affiliation: Gillings School of Public Health, University of North Carolina, Chapel Hill, NC, USA.
authors.forename: Deborah F
authors.initials: DF
authors.lastname: Tate
authors.affiliation: Brown University and The Miriam Hospital's Weight Control and Diabetes Research Center, Providence, RI, USA.
authors.forename: Dale S
authors.initials: DS
authors.lastname: Bond
authors.affiliation: Wake Forest School of Medicine, Winston-Salem, NC, USA.
authors.forename: Mark A
authors.identifier: 0000-0002-3711-1949
authors.initials: MA
authors.lastname: Espeland
authors.affiliation: Brown University and The Miriam Hospital's Weight Control and Diabetes Research Center, Providence, RI, USA.
authors.forename: Rena R
authors.initials: RR
authors.lastname: Wing
mesh_terms: D000293:Adolescent; D016497:Adolescent Health Services; D000328:Adult; D015444:Exercise; D005260:Female; D006801:Humans; D008297:Male; D009765:Obesity / Q000517:prevention & control*; D015203:Reproducibility of Results; D057185:Sedentary Behavior; D011795:Surveys and Questionnaires; D055815:Young Adult