Physical activity as a multitarget therapy for metabolically associated fatty liver disease

Metabolically associated fatty liver disease is a major public health problem in all countries. In 2020, the criteria for diagnosing the disease have fundamentally changed, risk factors have been specified, which requires a revision of existing approaches to therapy. Metabolically associated fatty liver disease, formerly called non-alcoholic fatty liver disease, is a hepatic manifestation of a multisystem disorder. The 2020 consensus of international experts proposed new diagnostic criteria for metabolically associated fatty liver disease. The diagnosis is made in the presence of steatosis (according to instrumental methods and/or biomarker studies and/or histological signs) in combination with one or more additional criteria: overweight or obesity, type 2 diabetes mellitus or metabolic disorders. The purpose of the literature review is to present the results of modern clinical studies and meta-analyzes on the effect of physical activity and, in particular, aerobic exercise on the course of the disease. Results. Exercise programs have proven effective in treating disease. All types of aerobic exercise – continuous, interval and combination – have a positive effect on triglyceride levels and body mass index. Moreover, continuous and intermittent aerobic exercise improves liver enzymes, in particular alanine aminotransferase, compared to the management of patients without physical activity. Meta-regression analysis showed that shorter intervention times (≤ 12 weeks) were more effective in reducing alanine aminotransferase levels. In clinical practice, it is not always possible to achieve targets. The limiting factors are the fact that patients with concomitant obesity and other comorbid pathology do not comply with the necessary physical activity regimens, do not reach the target indicators for energy consumption. Equally important are the issues of control of load tolerance, taking into account age, gender and other characteristics. Effective physical activity programs for metabolically associated fatty liver disease should be based on energy targets, effective and safe regimens, and tailored to the individual patient.

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