Microbiota and muscle highway — two way traffic

Exercise is a potent modulator of intestinal microbiota composition and function. In 2019, several studies uncovered biologically important links between skeletal muscle and the gut microbiota, revealing how the gut bacteria respond to an exercise challenge and have reciprocal roles in fuel availability, muscle function and endurance performance. Key advances Diet-induced changes in the composition of the gut microbiota markedly influence systemic metabolism, fuel availability and exercise capacity 4 , 5 . Treadmill endurance running capacity is decreased and ex vivo skeletal muscle contractile function is impaired in mice with a depleted gut microbiota: restoring the gut microbiota reverses these impairments 4 , 5 . Improved metabolic health and exercise performance in athletes is associated with increased microbial diversity and abundance of bacterial species 8 , 9 . Faecal microbiota transplantation of Veillonella atypica from humans after a strenuous exercise challenge significantly increases submaximal run time to exhaustion in mice 9 .