title: Differences in physical activity domains, guideline adherence, and weight history between metabolically healthy and metabolically abnormal obese adults: a cross-sectional study.
abstract: BACKGROUND
  Despite the accepted health consequences of obesity, emerging research suggests that a significant segment of adults with obesity are metabolically healthy (MHO). To date, MHO individuals have been shown to have higher levels of physical activity (PA), but little is known about the importance of PA domains or the influence of weight history compared to their metabolically abnormal (MAO) counterpart.
  
  
  OBJECTIVE
  To evaluate the relationship between PA domains, PA guideline adherence, and weight history on MHO.
  
  
  METHODS
  Pooled cycles of the National Health and Nutritional Examination Survey (NHANES) 1999-2006 (≥20 y; BMI ≥ 30 kg/m(2); N = 2,753) and harmonized criteria for metabolic syndrome (MetS) were used. Participants were categorized as "inactive" (no reported PA), "somewhat active" (>0 to < 500 metabolic equivalent (MET) min/week), and "active" (PA guideline adherence, ≥ 500 MET min/week) according to each domain of PA (total, recreational, transportation and household). Logistic and multinomial regressions were modelled for MHO and analyses were adjusted for age, sex, education, ethnicity, income, smoking and alcohol intake.
  
  
  RESULTS
  Compared to MAO, MHO participants were younger, had lower BMI, and were more likely to be classified as active according to their total and recreational PA level. Based on total PA levels, individuals who were active had a 70% greater likelihood of having the MHO phenotype (OR = 1.70, 95% CI: 1.19-2.43); however, once stratified by age (20-44 y; 45-59 y; and; ≥60 y), the association remained significant only amongst those aged 45-59 y. Although moderate and vigorous PA were inconsistently related to MHO following adjustment for covariates, losing ≥30 kg in the last 10 y and not gaining ≥10 kg since age 25 y were significant predictors of MHO phenotype for all PA domains, even if adherence to the PA guidelines were not met.
  
  
  CONCLUSIONS
  Although PA is associated with MHO, the beneficial effects of PA may be moderated by longer-term changes in weight. Longitudinal analysis of physical activity and weight change trajectories are necessary to isolate the contribution of duration of obesity, PA behaviours, and longer-term outcomes amongst MHO individuals.
authors.affiliation: School of Kinesiology and Health Science, 352 Norman Bethune College, York University, 4700 Keele Street, Toronto, ON, M3J1P3, Canada. tkanagas@yorku.ca.
authors.forename: Thirumagal
authors.initials: T
authors.lastname: Kanagasabai
authors.affiliation: School of Kinesiology and Health Science, 352 Norman Bethune College, York University, 4700 Keele Street, Toronto, ON, M3J1P3, Canada. nthakkar@yorku.ca.
authors.forename: Niels A
authors.initials: NA
authors.lastname: Thakkar
authors.affiliation: School of Kinesiology and Health Science, 352 Norman Bethune College, York University, 4700 Keele Street, Toronto, ON, M3J1P3, Canada. jennkuk@yorku.ca.
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Kuk
authors.affiliation: Brooks College of Health, University of North Florida, Jacksonville, FL, USA. j.churilla@unf.edu.
authors.forename: James R
authors.initials: JR
authors.lastname: Churilla
authors.affiliation: School of Kinesiology and Health Science, 352 Norman Bethune College, York University, 4700 Keele Street, Toronto, ON, M3J1P3, Canada. cardern@yorku.ca.
authors.forename: Chris I
authors.initials: CI
authors.lastname: Ardern
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015992:Body Mass Index; D001835:Body Weight / Q000502:physiology*; D003430:Cross-Sectional Studies; D005260:Female; D019983:Guideline Adherence; D006801:Humans; D007206:Individuality; D008297:Male; D024821:Metabolic Syndrome / Q000503:physiopathology*; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology*; D009765:Obesity / Q000503:physiopathology*; D013997:Time Factors; D015431:Weight Loss / Q000502:physiology*; D055815:Young Adult