High-, Moderate-Intensity Exercise Cuts NAFLD Risk
Both high- and moderate-intensity exercises are associated with lower levels of intrahepatic liquid (IHL) and a reduced risk for non-alcoholic fatty liver disease (NAFLD), according to a recent study.
Exercise training is commonly prescribed to help manage NAFLD. However, a consensus has not yet been established regarding which volume and intensity of exercise provides optimal benefit.
For their study, the researchers assessed 18 adults with obesity. Patients were randomly assigned to either 4 weeks of high-intensity interval training (HIIT) (4 min 80% VO2peak/3 min, 50% VO2peak) or moderate-intensity continuous exercise training (MICT) (55% VO2peak, approximately 60 min). Participants were subsequently matched for energy expenditure (approximately 400 kcal/session) and compared with 5 age-matched controls who did not exercise.
1H-MRS was used to measure IHL. Metabolic phenotype was determined via frequent blood samples that were assessed for glucose, insulin, c-peptide, and NEFA levels during a 180-minute liquid meal test.
Baseline body weight, visceral abdominal adiposity, and fasting insulin concentrations had been greater in the MICT group compared with the HIIT group. IHL was similar between both groups and higher than that of controls.
Ultimately, the researchers found that both exercise interventions reduced IHL, but this reduction was not statistically different between exercise intensities. Furthermore, both interventions had reduced postprandial insulin, c-peptide, and lipid peroxidation levels.
Neither HIIT nor MICT had decreased visceral abdominal adiposity, body mass, alanine aminotransferase, aspartate aminotransferase, or the hepatic apoptotic/inflammatory markers cytokeratin 18 or fetuin a.
“Collectively, these findings indicate that energy-matched high-intensity and moderate-intensity exercise are effective at decreasing IHL and NAFLD risk that is not contingent upon reductions in abdominal adiposity or body mass,” the researchers concluded.
—Christina Vogt
Reference:
Winn NC, Ying L, Rector RS, Parks EJ, Ibdah JA, Kanaley JA. Energy-matched moderate and high intensity exercise training improves nonalcoholic fatty liver disease risk independent of changes in body mass or abdominal adiposity – a randomized trial [Published online September 20, 2017]. Metab Clin Exp. http://dx.doi.org/10.1016/j.metabol.2017.08.012.