Exercise-induced adaptations to homeostasis of reactive oxygen species in skeletal muscle

Reactive oxygen species are generated by multiple mechanisms during contractile activity in exercising skeletal muscle and are recognised to play a role in signaling adaptations to the contractions. The sources of the superoxide and hydrogen peroxide generated are now relatively well understood but how the resulting low concentrations of hydrogen peroxide induce activation of multiple signaling pathways remains obscure. Several theories are presented together with accumulating evidence that 2-Cys peroxiredoxins may play a role of “effector” proteins in mediating the signaling actions of hydrogen peroxide. Identification of the mechanisms underlying these pathways offers the potential in the longer term for development of novel interventions to maintain exercise responses in the elderly with the potential to maintain muscle mass and function and consequent quality of life. • Reactive oxygen species are generated by multiple mechanisms during contractile activity in exercising skeletal muscle. • These species, and particularly hydrogen peroxide play a role in signaling adaptations to muscle contractions. • 2-Cys peroxiredoxins may play a role as “effector” proteins in mediating the signaling actions of hydrogen peroxide. • Redox signaling pathways become dysregulated in aging contributing to skeletal muscle loss and weakness. • Understanding mechanisms underlying these pathways may identify interventions to help maintain muscle mass and function.