Yes, sprints, box jumps and burpees are not fun and never will be. But grinning (or cursing) and getting on with it may be one of the best things you can do for your health. A recent study published in the eLife journal on May 31 confirms as much. According to the study, HIIT boosts the quantity of protein in skeletal muscle essential for energy metabolism and muscle contraction and chemically alters key metabolic proteins. This, in turn, may explain the beneficial effects of HIIT on metabolism and pave the way for additional studies exploring how exercise impacts these processes.
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According to the study's first and co-corresponding author Morten Hostrup, Associate Professor at the Department of Nutrition, Exercise, and Sports at the University of Copenhagen, Denmark, exercise has many benefits and can help prevent and treat metabolic disorders. "We wanted to understand how exercise alters the muscles' protein content and how it regulates the activity of these proteins through a chemical reaction called acetylation," he said, referring to the process which occurs when a member of the small molecule group, acetyl, combines with other molecules. This, in turn, affects the behaviour of the proteins.
The research was conducted on eight healthy, untrained male volunteers who were placed into a five-week-long high-intensity cycling training program. The sessions, conducted three times a week, saw these volunteers do four to five rounds of interval training: four minutes of cycling at a target rate of more than 90% of their maximum heart rate, followed by a two-minute rest.
The study stated that mass spectrometry was then used to analyse changes to the composition of 3,168 proteins in tissue samples collected from the participants' thighs before the study and after they completed the training. "Their analyses showed an increase in the production of proteins used to build mitochondria, which produce energy in cells, and in proteins related to muscle contractions. The team also identified increased acetylation of mitochondrial proteins and enzymes that are involved in the production of cellular energy. Additionally, they observed changes in the amount of proteins that reduce the skeletal muscle's calcium sensitivity, which is essential for muscle contractions, " said the study.
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The results of the study not only confirm some well-known changes to skeletal muscle proteins that occur after exercise, but they also identify new ones. Reduced calcium sensitivity may explain why it can be harder for muscle contraction to occur after an athlete becomes fatigued, stated the study, also suggesting that exercise-induced changes in the regulation of proteins through acetylation may contribute to boosting metabolism. "We hope our work will stimulate further research into how exercise helps improve metabolic health in humans," said co-corresponding author Atul Deshmukh, Associate Professor at the Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen.
