EN
Essential processes in the regeneration of an injured muscle include proliferation of satellite cells and vascularization. Myogenesis and angiogenesis are prerequisites for the subsequent morphological and functional healing of the injured muscle, leading to the reconstruction of the damaged myocytes and vessels, restoration of the blood fl ow and restoration of the oxygen supply to the tissue. Nitric oxide (NO) plays a key role in satellite cells activation. It acts as a signal molecule and vasodilator, promotes expression genes for many growth factors being extracellular signals regulating the functions of the muscular, vascular and nervous systems. NO is produced by three isoenzymes, called nitric oxide synthases (NOS), present in skeletal muscle. The disturbance equilibrium between eNOS and iNOS activities results in pro-apoptotic NO activity and muscle atrophy. A recent study has shown a relationship between NO generation and delayed onset muscle soreness in response to intense resistance exercise. NO generation can be modulated by physical activity, systemic hypoxia (altitude training) or NO precursors such as L-arginine. The present review provides a current overview of NO effects on skeletal muscles and nutritional strategies based on L-arginine intake to aid muscle regeneration.