A bacterium capable of building human muscle has been discovered

Spanish scientists have made an unexpected discovery: certain gut bacteria can directly influence muscular strength by affecting energy processes in the body.

As reported by TUT.AZ with reference to the journal Gut, a team of researchers from the University of Almería has established that the bacterium Roseburia inulinivorans is capable of exerting a notable positive influence on human physical strength.

As part of a large-scale experiment, the scientists conducted a detailed study of the gut microbiome of two groups of volunteers: young people aged 18–25 and elderly participants over 65 with low levels of physical activity. All subjects underwent a series of strength tests, including grip strength measurement, leg press, and bench press.

The data obtained proved highly telling: bacteria of the genus Roseburia were found significantly more often in individuals with higher strength indicators. Of particular interest was the species R. inulinivorans — its presence correlated with better results across several tests simultaneously. Among elderly participants in whose gut this bacterium was detected, grip strength was nearly 30% higher, while among younger participants, not only greater strength but also noticeably better endurance was recorded.

To confirm the results, the scientists conducted an additional experiment on animals: after the bacterium was administered to mice, their strength increased by approximately one-third. In addition, the test rodents showed growth of muscle fibers and an increase in the number of fast-twitch muscle cells responsible for powerful and explosive movements.

The researchers believe that the mechanism of action is linked to the bacterium's influence on amino acid metabolism and energy processes directly within muscle tissue. In the long term, the data obtained could serve as a foundation for developing a new generation of probiotics aimed at maintaining physical fitness and strengthening muscular power.