title: Association of cardiorespiratory fitness with insulin sensitivity in overweight and obese postmenopausal women: a Montreal Ottawa New Emerging Team study.
abstract: The purpose of this study was to examine the relation between insulin sensitivity and cardiorespiratory fitness in overweight and obese postmenopausal women. The study population consisted of 127 overweight and obese postmenopausal women (age, 57.7 +/- 4.8 years; body mass index, 32.7 +/- 4.7 kg/m(2)). Subjects were classified by dividing the entire cohort into tertiles (T) based on insulin sensitivity expressed per kilograms of lean body mass (LBM) (T1, <10.9; T2, 10.9-12.9, T3, >12.9 mg/min per kilogram of LBM, respectively). Outcome measures were body composition (dual-energy x-ray absorptiometry), visceral adipose tissue (computed tomography), insulin sensitivity (hyperinsulinemic-euglycemic clamp), cardiorespiratory fitness (indirect calorimetry), lower-body muscle strength (1 maximal repetition), physical activity energy expenditure (doubly labeled water), fasting lipids, and inflammatory profile. We found a significant positive relationship between insulin sensitivity and cardiorespiratory fitness (r = 0.25, P = .005). Moreover, cardiorespiratory fitness was higher in the T3 group compared to the T1 group (36.2 +/- 6.1 vs 33.1 +/- 5.0 mL/kg LBM per minute, respectively; P = .028). However, the difference was no longer significant after controlling for visceral adipose tissue or muscle strength. Finally, cardiorespiratory fitness was an independent predictor of insulin sensitivity. High levels of cardiorespiratory fitness are associated with higher levels of insulin sensitivity in overweight and obese postmenopausal women. Moreover, visceral adipose tissue accumulation or muscle strength may be potential mediators of this relationship.
authors.affiliation: Department of Nutrition, University of Montreal, Montreal, Quebec, Canada H3T 1A8.
authors.forename: Virginie
authors.initials: V
authors.lastname: Messier
authors.forename: Florin M
authors.initials: FM
authors.lastname: Malita
authors.forename: Rémi
authors.initials: R
authors.lastname: Rabasa-Lhoret
authors.forename: Martin
authors.initials: M
authors.lastname: Brochu
authors.forename: Antony D
authors.initials: AD
authors.lastname: Karelis
mesh_terms: D001823:Body Composition; D015331:Cohort Studies; D005260:Female; D006321:Heart / Q000503:physiopathology*; D006801:Humans; D007333:Insulin Resistance; D050152:Intra-Abdominal Fat / Q000000981:diagnostic imaging; D008875:Middle Aged; D053580:Muscle Strength; D009765:Obesity / Q000000981:diagnostic imaging / Q000503:physiopathology*; D050177:Overweight / Q000000981:diagnostic imaging / Q000503:physiopathology*; D010809:Physical Fitness; D017698:Postmenopause; D011237:Predictive Value of Tests; D012137:Respiratory System / Q000503:physiopathology*; D014057:Tomography, X-Ray Computed