Clinical Trial: Exercise Dose and Nonalcoholic Fatty Liver Disease

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

Official Title: Exercise Dose and Nonalcoholic Fatty Liver Disease

Brief Summary: The purpose of this research is to provide a better understanding of how exercise (walking) affects non-alcoholic fatty liver disease (NAFLD) in overweight people. NAFLD, which is common in obese people, occurs when the liver has too much fat.

Detailed Summary:

Non-alcoholic fatty liver disease (NAFLD) affects about 33% of adults in the United States. The prevalence of NAFLD is four to five times higher in obese than lean persons and is associated with insulin resistance and the metabolic syndrome. Decreasing calorie intake and increasing physical activity has been recommended as primary therapy for NAFLD, but the independent effect of aerobic exercise is unknown. The current exercise guidelines for disease prevention and weight management range from 150 min/wk, recommended by the Centers for Disease Control and the American College of Sports Medicine, to 300 min/wk, recommended by the Institute of Medicine. However, it is not known whether aerobic exercise alone can improve NAFLD, and which recommended dose of exercise might have the most beneficial effects. The purpose of this proposal is to determine the effect of moderate intensity endurance exercise on: 1) hepatic fat content; 2) hepatic lipoprotein kinetics; and 3) plasma inflammatory markers. We hypothesize that aerobic exercise will decrease hepatic fat content, improve VLDL kinetics, and decrease inflammation in a dose-dependent fashion. The results from this study will help determine exercise guidelines for obese patients with NAFLD, and lay the groundwork for future studies evaluating the effects of exercise on metabolic diseases associated with obesity.

This proposal involves conducting a randomized controlled trial that will randomize obese subjects with NAFLD (> 10% hepatic fat content) to one of two groups: Group 1 (Control, no exercise) and Group 2 (Moderate Intensity Aerobic Exercise- 150 min/wk to 300 min/wk of supervised exercise performed at 45-55% of O2 max).


Sponsor: Washington University School of Medicine

Current Primary Outcome: The effect of aerobic exercise on: Intrahepatic fat content [ Time Frame: 3 years ]

Original Primary Outcome: The effect of low and moderate doses of aerobic exercise on: Intrahepatic fat content [ Time Frame: 3 years ]

Current Secondary Outcome:

  • VLDL-triglyceride (TG) and VLDL-Apolipoprotein B (apoB) kinetics [ Time Frame: 3 years ]
  • Insulin action in liver (suppression of glucose production), muscle (stimulation of glucose uptake), and adipose tissue (suppression of lipolysis). [ Time Frame: 3 years ]
  • Plasma markers of inflammation [ Time Frame: 3 years ]
  • Potential cellular mechanisms responsible for changes in insulin action and inflammation [ Time Frame: 3 years ]


Original Secondary Outcome: Same as current

Information By: Washington University School of Medicine

Dates:
Date Received: October 9, 2008
Date Started: May 2006
Date Completion:
Last Updated: September 2, 2011
Last Verified: September 2011