Abstract 46: A Randomized Trial of Moderate and Intensive Exercise on Fatty Liver and Cardiometabolic Risk Factors in Obese Adults

Abstract

Corresponding authors: Shu-yu Yang, Xiamen Diabetes Institute, Department of Endocrinology and Metabolism, The First Hospital of Xiamen, Xiamen University, 55 Zhenhai Road, Xiamen 361003, China ( xmyangshuyu@126.com). Jiang He, MD, PhD, Department of Epidemiology, Tulane University School of Public Health and Tropical Medicine, 1440 Canal St, Ste 2000, New Orleans, LA 70112 ( jhe@tulane.edu ). Xiao-Ying Li, MD, PhD, Department of Endocrinology and Metabolism, Rui-Jin Hospital, Shanghai Jiao-Tong University School of Medicine, 197 Rui-Jin 2nd Road, Shanghai 200025 (lixy@sibs.ac.cn). Introduction: Nonalcoholic fatty liver disease (NAFLD) and its cardiovascular complications are common public health problems. Hypothesis: Although the benefit of exercise on NAFLD and cardiometabolic risk factors is documented, the effects of intensive and moderate exercise on these outcomes have not been thoroughly investigated.. Methods: We conducted a randomized controlled trial among 220 individuals aged 40-65 years with a waist circumference of ≥90 cm in men and ≥85 cm in women. NAFLD was defined by proton magnetic resonance spectroscopy (1H-MRS). Participants were randomly assigned to the intensive exercise group (vigorous exercise at 65-80% maximum oxygen consumption by running on a treadmill 30 min/day and 5 days/week for 6 months, followed by moderate exercise by brisk walking 150 min/week for another 6 months), the moderate exercise group (brisk walking 150 min/week for the entire 12 months), or the usual care control (lifestyle counseling for 12 months). The primary outcome was the change of intra-hepatic triglyceride content as determined by 1 H-MRS. Secondary outcomes were metabolic risk factors. Results: At 12 months, the mean change of intra-hepatic triglyceride content from baseline was -6.10% in the intensive exercise, -5.91% in the moderate exercise, and -2.73% in the control groups (P<0.0001). Compared to the control group,the intensive and moderate exercise groups had significant net reductions of intra-hepatic triglyceride content at 6 months (-4.56%, 95% CL-6.71 to -2.42, p<0.001 for intensive and -3.86%, 95% CL-6.01 to -1.71, p<0.001 for moderate) and 12 months (-3.37%, 95% CL-5.52 to -1.22, p<0.001 for intensive, and -3.19%, 95% CL-5.34 to -1.04, p<0.001 for moderate). The net changes of intra-hepatic triglyceride content were not significantly different between the two exercise groups. Both intensive and moderate exercise reduced waist circumference, body weight, and blood pressure; additionally, intensive exercise reduced body fat mass, visceral fat, and body fat percent. Conclusions: Moderate intensity and vigorous intensity exercise were equally effective in improving NAFLD and blood pressure while vigorous exercise produced greater reductions of body fat.