Effects of weight loss vs aerobic exercise training on risk factors for coronary disease in healthy, obese, middle-aged and older men. A randomized controlled trial

Abstract

<h3>Objective.</h3> —To compare the effects of weight loss vs aerobic exercise training on coronary artery disease risk factors in healthy sedentary, obese, middle-aged and older men. <h3>Design.</h3> —Randomized controlled trial. <h3>Subjects.</h3> —A total of 170 obese (body mass index, 30±1 kg/m²[mean±SEM]), middle-aged and older (61 ±1 years) men. <h3>Interventions.</h3> —A 9-month diet-induced weight loss intervention, 9-month aerobic exercise training program, and a weight-maintenance control group. <h3>Main Outcome Measures.</h3> —Change in body composition, maximal aerobic capacity (Vo₂max), blood pressure, lipoprotein concentrations, and glucose tolerance. <h3>Results.</h3> —Forty-four of 73 men randomized to weight loss completed the intervention and had a 10% mean reduction in weight (-9.5±0.7 kg;<i>P</i>&lt;.001), with no change in Vo₂max. Forty-nine of 71 men randomized to aerobic exercise completed the intervention, increased their Vo₂max by a mean of 17% (<i>P</i>&lt;.001), and did not change their weight, whereas the 18 men who completed in the control group had no significant changes in body composition or Vo₂max. Weight loss decreased fasting glucose concentrations by 2%, insulin by 18%, and glucose and insulin areas during the oral glucose tolerance test (OGTT) by 8% and 26%, respectively (<i>P</i>&lt;.01). By contrast, aerobic exercise did not improve fasting glucose or insulin concentrations or glucose responses during the OGTT but decreased insulin areas by 17% (<i>P</i>&lt;.001). In analysis of variance, the decrement in fasting glucose and insulin levels and glucose areas with intervention differed between weight loss and aerobic exercise when compared with the control group (<i>P</i>&lt;.05). Similarly, weight loss but not aerobic exercise increased high-density lipoprotein cholesterol levels (+13%) and decreased blood pressure compared with the control group. In multiple regression analyses, the improvement in lipoproteins and glucose metabolism was related primarily to the reduction in obesity. <h3>Conclusions.</h3> —These results suggest that weight loss is the preferred treatment to improve coronary artery disease risk factors in overweight, middle-aged and older men. (<i>JAMA</i>. 1995;274:1915-1921)