The Effects Of Exercise Training On Maintenance Of Abdominal Adiposity And Lipoproteins During Weight Regain

Abstract

Purpose The primary purpose was to investigate the effect of exercise training on maintaining weight loss induced improvements in metabolic fitness, specifically abdominal adiposity and lipoproteins, during weight regain. Secondarily, we examined the relationships between abdominal adiposity and lipoproteins during weight loss and regain. Methods Nineteen overweight to class I obese (BMI = 25–34.9) individuals (6 males,13 females) age 18–43 y participated in this 10 wk, two phase study. In phase I, subjects underwent 6 wk of modest energy restriction (∼500 kcal/d) and exercise training to induce a 5% reduction in body weight. During phase II, subjects were randomized into either a weight maintenance or partial weight regain group. Both groups continued exercise training. The maintain group slightly increased energy intake (+∼100 kcal/d) to achieve weight maintenance, while the regain group significantly increased energy intake (+∼600 kcal/d) to induce regain of 50% of initial weight loss. Exercise training during both phases consisted of 45 min/d, 5d/wk of walking to mild treadmill jogging at 60%VO2max. Lipoproteins and abdominal fat were assessed at three testing sessions: pre-weight loss (baseline), post Phase I treatment (wk 6), and post Phase II treatment (wk 11). RESULTS Weight loss resulted insignificant reductions in BMI, body fat %, total, subcutaneous, and intra-abdominal fat, triglyceride incremental peak (Peak1 TG), triglyceride incremental area under the curve (TG-AUCI), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and LDL1-C. Exercise training maintained changes in body fat %, total, subcutaneous, and intra-abdominal fat, Peak1 TG, and TG-AUC1, but was not successful at maintaining TC, LDL-C, LDL1 -C, or mean LDL size during weight regain. Changes in abdominal adiposity and lipoproteins were not significantly correlated during weight loss or weight regain. CONCLUSION Weight loss, induced by the combination of diet and exercise, is effective at improving many of metabolic syndrome parameters, and exercise training was effective at maintaining some of these improvements during partial weight regain. Finally, changes in abdominal adiposity during weight loss and partial weight regain were not related to changes in lipoproteins. Supported by: The MU Research Council and the MU College of Human Environmental Sciences: Margaret Mangel Catalyst Fund.