The increased knowledge of the genetic basis of a broad range of muscle diseases has led to a dramatic alteration in the investigation of muscle diseases. Muscle biopsy has become a strong instrument not just to provide diagnosis, but to make tissue accessible for genetic studies, and to elementary scientists for biomedical research, as well as to examine mitochondrial dysfunction and the mitochondrial DNA integrity in oxidation. Precise interpretation of muscle biopsy to catch cell dysfunction/damage/death or absence/abnormality of a protein or genetic defect by the sophisticated technologies is crucial to direct the diagnosis of different muscle disorders. This book discusses the process and interpretation of muscle biopsy, its applications in the culture of myotubes and membrane transport studies. It discusses the developments in the elementary techniques of muscle biopsy for a neuroscientist, as well as, explores phosphorylation in different disorders like obesity, type 2 diabetes mellitus, and peripheral vascular disease, with comprehensive descriptions on methodology.