title: Exercise-induced reduction in obesity and insulin resistance in women: a randomized controlled trial.
abstract: OBJECTIVE
  To determine the effects of equivalent diet- or exercise-induced weight loss and exercise without weight loss on subcutaneous fat, visceral fat, and insulin sensitivity in obese women.
  
  
  METHODS
  Fifty-four premenopausal women with abdominal obesity [waist circumference 110.1 +/- 5.8 cm (mean +/- SD)] (BMI 31.3 +/- 2.0 kg/m2) were randomly assigned to one of four groups: diet weight loss (n = 15), exercise weight loss (n = 17), exercise without weight loss (n = 12), and a weight-stable control group (n = 10). All groups underwent a 14-week intervention.
  
  
  RESULTS
  Body weight decreased by approximately 6.5% within both weight loss groups and was unchanged in the exercise without weight loss and control groups. In comparison with controls, cardiorespiratory fitness improved within the exercise groups only (p < 0.01). Reduction in total, abdominal, and abdominal subcutaneous fat within the exercise weight loss group was greater (p < 0.001) than within all other groups. The reduction in total and abdominal fat within the diet weight loss and exercise without weight loss groups was greater than within controls (p < 0.001) but not different from each other (p > 0.05). Visceral fat decreased within all treatment groups (p < 0.008), and these changes were not different from each other. In comparison with the control group, insulin sensitivity improved within the exercise weight loss group alone (p < 0.001).
  
  
  CONCLUSIONS
  Daily exercise without caloric restriction was associated with substantial reductions in total fat, abdominal fat, visceral fat, and insulin resistance in women. Exercise without weight loss was also associated with a substantial reduction in total and abdominal obesity.
authors.affiliation: School of Physical and Health Education, Department of Medicine, Division of Endocrinology and Metabolism, Queen's University, Kingston, Ontario, Canada. rossr@post.queensu.ca
authors.forename: Robert
authors.initials: R
authors.lastname: Ross
authors.forename: Ian
authors.initials: I
authors.lastname: Janssen
authors.forename: Jody
authors.initials: J
authors.lastname: Dawson
authors.forename: Ann-Marie
authors.initials: AM
authors.lastname: Kungl
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Kuk
authors.forename: Suzy L
authors.initials: SL
authors.lastname: Wong
authors.forename: Thanh-Binh
authors.initials: TB
authors.lastname: Nguyen-Duy
authors.forename: SoJung
authors.initials: S
authors.lastname: Lee
authors.forename: Katherine
authors.initials: K
authors.lastname: Kilpatrick
authors.forename: Robert
authors.initials: R
authors.lastname: Hudson
mesh_terms: D000005:Abdomen; D000273:Adipose Tissue; D000328:Adult; D000886:Anthropometry; D001823:Body Composition; D001824:Body Constitution; D015992:Body Mass Index; D004038:Diet, Reducing; D002149:Energy Intake; D015444:Exercise; D005260:Female; D005951:Glucose Tolerance Test; D006801:Humans; D007333:Insulin Resistance; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D018482:Muscle, Skeletal; D009765:Obesity / Q000628:therapy*; D010809:Physical Fitness; D017697:Premenopause; D015431:Weight Loss