What about fatty liver? Aerobic exercise can significantly reduce liver fat!

▎ WuXi AppTec content team editor

Non-alcoholic fatty liver disease (NAFLD), which affects about 20%-30% of people worldwide, is one of the most common liver diseases. Its main feature is that people who do not drink excessive alcohol have too much fat accumulation in the liver, which may lead to cirrhosis and liver cancer in the long run.

Nonalcoholic fatty liver disease may be associated with obesity and metabolic syndrome. Therefore, lifestyle interventions for weight loss are still the main methods for managing non-alcoholic fatty liver disease.

Screenshot source: JCEM

Recent studies published in The Journal of Clinical Endocrinology & Metabolism have shown that both high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) can be effective in improving non-alcoholic fatty liver disease.

High-intensity interval training (HIIT) refers to multiple short-term, high-intensity exercises, between which are connected by low-intensity exercises. This is a movement that alternates between high-intensity and low-intensity training.

In this review, the researchers analyzed 19 studies involving a total of 745 adults. The researchers analyzed the relationship between participants' weekly exercise (minutes) and energy expenditure (kcal) and changes in liver fat content. Measurements of liver fat content are assessed by non-invasive techniques such as proton magnetic resonance spectroscopy (H-MRS) and magnetic resonance imaging (MRI).

The analysis showed that compared to no exercise:

Both HIIT and MICT cause a modest reduction in liver fat content. Specifically, HIIT decreased by 2.85% (P=0.005, lower level of evidence) and MICT decreased by 3.14% (P

Although HIIT uses less time and effort, HIIT is equally effective at reducing liver fat compared to MICT exercises (P=0.721, medium-grade evidence).

In addition, the researchers also found that the energy expenditure related to total exercise is also related to changes in fat content in the liver.

Dr Angelo Sabag, author of the study and a researcher at the NICM Institute for Health, noted: "Non-alcoholic fatty liver disease is a predictor of metabolic disorders and is closely related to the development and severity of various diseases, such as type 2 diabetes. Serious complications can occur if left untreated.

Our research shows that both HIIT and MICT can improve fat in the liver to some extent, helping to reduce non-alcoholic fatty liver disease. Regular aerobic exercise is an important management intervention, whether it's HIIT or MICT, and the study provides practical recommendations for clinical practice. ”

Dr Sabag added: "Another interesting finding is that even if we don't exercise up to the recommended amount of exercise, as long as we do moderate-intensity and above exercise on a regular basis, we can still significantly improve liver fat. Further research is recommended to determine the importance of exercise (such as exercise intensity) for fat reduction in the liver. ”