The Clock Thickens: Morning or Evening Training for the Treatment of NAFLD?

The aim of the study is to identify the effect of exercise timing on NAFLD. Additionally, we aim to increase the understanding of the exercise-related modulation of the metabolic and inflammatory processes causing NAFLD, including insulin resistance and dysbiosis of the gut microbiota. Forty obese patients with NAFLD will be enrolled by randomization to participate in an exercise training program over 12 weeks, either in the morning (n=20) or evening (n=20). Blood and stool samples will be collected before, during and after the intervention to monitor diagnostic markers such as liver enzymes (AST, ALT, GGT, etc.) and changes of the gut microbiota with exercise, respectively. Moreover, mixed meal tolerance tests will be performed before and after the intervention to monitor insulin sensitivity and hepatic fat content and cardiovascular parameters (e.g. arterial stiffness) will be monitored via MRI. Throughout the study, physical fitness will be assessed and monitored using steep ramp tests. Patients will be randomized for a supervised, standardized 50 min morning or evening training, with both progressive endurance and strength elements, in a frequency of 3 times a week for 12 weeks.