PHYSICAL-ACTIVITY AS A PREDICTOR OF WEIGHT MAINTENANCE IN PREVIOUSLY OBESE SUBJECTS

We examined the association between exercise and weight loss maintenan ce in a group of 45 previously obese subjects 2 years post very-low-ca lorie diet (VLCD) to suggest exercise goals for this population, At ba seline, subjects weighed a mean 100 kg and had a mean total cholestero l (TC) of 5.8 mmol/L. With VLCD they lost an average 28 kg and decreas ed their TC by 1.6 mmol/L. Two years post-VLCD their weight and lipids were measured and they completed a physical activity survey (Paffenba rger). Subjects were grouped into tertiles by reported exercise levels : low active (< 850 kcals per week), moderate active (850-1575 kcals p er week) and high active (> 1575 kcals per week). Walking accounted fo r the greatest calorie expenditure (65%). Analysis of variance showed that baseline characteristics and weight and blood lipid changes durin g the VLCD did not differ (P>0.05) among groups. At follow-up, high ac tive patients maintained significantly greater weight loss, had a lowe r percent regain and a significantly greater decrease in total cholest erol (P < 0.05) than less active patients. Multiple regression analysi s indicated that total exercise calories independently predicted overa ll weight toss and percent regain (r = 0.66 and r = 0.62, respectively ), Exercise calories also predicted total cholesterol change (r=-0.37) . The high active group walked more miles (16.2 per week) than the low and moderate active groups (4.8 and 9.1 per week, respectively) and e xercised more days per week (5.3 vs, 1.9 and 3.7). The low and moderat e active groups regained virtually equal amounts of weight, even thoug h the moderate group expended twice as many kcals per week as the low active group. These data demonstrate that increased exercise levels en hance weight loss maintenance.