Table 7.

Classification of fiber types according to the traditional classification based on ATPase staining, the oxidative phosphorylation capacity, the immunohistochemical classification based on myosin heavy chain (MYH) isoforms, and the classification based on the proteomic data.

Fiber Type	Traditional Classification (Based on ATPase Staining)	Oxidative Phosphorylation Capacity	Immunohistochemical Classification via MYH Isoform	Proteomic Classification
Type I	Slow	Very high	MYH7	Highly oxidative
Type IIa	Fast	High	MYH2	Highly oxidative
Type IIb	Fast	Very low	MYH4	Highly glycolytic
Type IIx	Fast	Low	MYH1	Oxidative and glycolytic