According to the findings, exercise-induced alterations in protein regulation via acetylation may help to enhance metabolism.

Scientists have shed new light on the effects of high-intensity interval training (HIIT) on human skeletal muscle in a study published in eLife. The findings imply that high-intensity interval training (HIIT) increases the number of proteins in skeletal muscle that are important for energy metabolism and muscular contraction and chemically altering key metabolic proteins. These findings could explain why HIIT improves metabolism and pave the path for more research into how exercise affects these systems.

"Exercising provides a variety of health benefits that can help prevent and treat metabolic illnesses, and this is likely due to changes in skeletal muscle energy usage. We wanted to know how exercise changes the protein content of muscles and how acetylation, a chemical reaction, regulates the activity of these proteins "Morten Hostrup, Associate Professor at the University of Copenhagen's Department of Nutrition, Exercise, and Sports is the study's first and co-corresponding author. Acetylation is a process in which acetyl, a tiny molecule, reacts with other molecules to change the behavior of proteins.

Their findings revealed an increase in the creation of proteins connected to muscular contractions as well as proteins necessary to create mitochondria, which provide energy in cells. Increased acetylation of mitochondrial proteins and enzymes involved in cellular energy production was also discovered by the researchers. They also saw alterations in the number of proteins that diminish the calcium sensitivity of skeletal muscle, which is necessary for muscular contractions.

The findings validate and identify some well-known alterations in skeletal muscle proteins that occur after exercise. Reduced calcium sensitivity, for example, could explain why muscle contraction becomes more difficult when an athlete becomes weary.

"Our study provides new information about how skeletal muscle adapts to exercise training using state-of-the-art proteomics technology, including the identification of novel exercise-regulated proteins and acetyl-sites," says co-corresponding author Atul Deshmukh of the Novo Nordisk Foundation Center for Basic Metabolic Research at the University of Copenhagen. "We hope that our findings will spur more research into how exercise can help humans improve their metabolic health."