title: Arrangement of fiber types within fascicles of human vastus lateralis muscle.
abstract: A total of 106 fascicles at 6 predetermined areas of the vastus lateralis muscle from 9 healthy men, aged 18 to 40 years, were analyzed. Fibers in a fascicle were divided into layers according to their relation to the perimysium. In each layer the proportions of type 1 and 2, subdivided into 2a, 2b, and 2c fibers were determined and normalized by the fiber type proportion in the whole fascicle. A consistent arrangement of fiber types within the fascicles was obtained, regardless of subject, sampling site, fiber type proportion, and fascicle size. A high proportion of 2b fibers on the border, a prevalence of type 1 fibers in the layer beneath, and a rather uniform distribution of 2a fibers in all layers are the main characteristics of the distribution of fibers in a fascicle. Developmental processes in fiber type differentiation most probably constitute the basis for fiber type arrangement, which can further be influenced by local factors.
authors.affiliation: Faculty of Electrical and Computer Engineering, University of Ljubljana, Yugoslavia.
authors.forename: F
authors.initials: F
authors.lastname: Pernus
authors.forename: I
authors.initials: I
authors.lastname: Erzen
mesh_terms: D000251:Adenosine Triphosphatases / Q000032:analysis; D000328:Adult; D006801:Humans; D008297:Male; D009132:Muscles / Q000033:anatomy & histology* / Q000737:chemistry; D013848:Thigh
chemical_list: D000251:Adenosine Triphosphatases