Nowadays, dramatic changes in the lifestyle and diet of the global population are causing the prevalence of NAFLD increasing rapidly, in parallel with that of obesity and diabetes. Previous studies found an inverse relationship between physical activity and the risk of NAFLD. However, clinical trials examining the therapeutic benefit of physical activity in NAFLD have reported inconsistent results.
ST Wang et al. (Department of Epidemiology and Health Statistics, Fujian Medical University, Fuzhou, China) performed a comprehensive search for English and Chinese language publications on PubMed and China National Knowledge Infrastructure (CNKI) databases for their meta-analysis of 9 randomized controlled trials with a cumulative total of 951 participants.
Physical activity was found associated with small reductions in hepatic enzyme parameters, and significant small improvements in serum lipid parameters. Significant improvement was also found in intra-hepatic lipid content. Subgroup analysis suggested both aerobic exercise alone and resistance exercise alone can improve most liver function and longer period of exercise generally had better improvement effect.
These findings suggest that physical activity alone can only slightly improve hepatic enzyme levels, most serum lipid levels and intra-hepatic lipid content in non-diabetic patients with NAFLD.