Brazilian study from Unicamp reveals how strength training affects the liver and improves metabolism

The scientists focused on verifying whether MASLD caused by obesity modified gene function. To do this, an experiment was conducted using obese rats fed a high-fat diet. One group remained sedentary, while the other was subjected to a weight training protocol. After genetic analyses, it was observed that, in just eight weeks of training, there was a methylation of the MTCH2 gene, which is linked to hepatic energy metabolism and fat accumulation.

Methylation, a type of genetic alteration that does not change the DNA sequence, consists of adding a methyl chemical molecule to the DNA, which can activate or inhibit gene expression. In the studied case, this modification inhibited MTCH2.

Mechanisms of Exercise Action

Initially, obesity causes inflammation in hepatic mitochondria, essential structures for cellular energy generation, leading the organ to operate in a deregulated manner, including excessive control of the MTCH2 gene. Conversely, weight training attenuates this inflammation and provides energy to the liver, aiding in the regulation of MTCH2 and consequently reducing accumulated fat.

Additionally, exercise increased the amount of ATP5 protein, crucial for mitochondrial energy production and which also helps modulate MTCH2. Another benefit noted was the reduction in the activity of proteins related to fibrosis and uncontrolled cell growth, processes often stimulated by obesity.

Improvement in Insulin Sensitivity

The trained rodents showed recovery of insulin sensitivity, a characteristic generally lost due to fat accumulation in the liver. Insulin resistance leads the organ to continue producing glucose even when it is already present in the blood, which contributes to the hyperglycemia typical of type 2 diabetes.

The authors concluded that their results offer new evidence that resistance exercise stimulates the remodeling of mitochondrial and insulin signaling, strengthening its therapeutic potential in managing obesity.