Exercise-induced reduction in obesity and insulin resistance in women: a randomized controlled trial

Obes Res. 2004 May;12(5):789-98. doi: 10.1038/oby.2004.95.


Objectives: 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.

Research methods and procedures: 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).

Discussion: 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.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abdomen
  • Adipose Tissue
  • Adult
  • Anthropometry
  • Body Composition
  • Body Constitution
  • Body Mass Index
  • Diet, Reducing
  • Energy Intake
  • Exercise*
  • Female
  • Glucose Tolerance Test
  • Humans
  • Insulin Resistance*
  • Magnetic Resonance Imaging
  • Middle Aged
  • Muscle, Skeletal
  • Obesity / therapy*
  • Physical Fitness
  • Premenopause
  • Weight Loss