title: Age-related morphometric characteristics of human skeletal muscle in male subjects.
abstract: OBJECTIVE
  The purpose of the present study is to investigate the age-related changes in muscle biopsies from the quadriceps femoris in male subjects of different ages.
  
  
  METHODS
  A histological and histochemical study was performed on specimens from the quadriceps femoris from 8 males divided into two groups, under 50 and over 70 years of age. The following measurements were performed: a) number of type 1 and 2 fibres, b) diameter of type 1 and 2 fibres, c) percentage of the number and mean diameter of the two types in the interior and the peripheral area of fascicles.
  
  
  RESULTS
  The proportion of type 2 fibres decreased significantly with age (p < 0.005), especially in the periphery of the fascicles, but the proportion of type 1 fibres was not significantly changed. The correlation of fibre size with age showed that type 2 fibres decrease in size with age. This finding was more evident in the periphery of the fascicles (p < 0.05).
  
  
  CONCLUSIONS
  We found that type 2 skeletal muscle fibres decreased in size and proportion with increasing age. The existence of these age changes should be taken into account in the interpretation of muscle biopsies of aged individuals.
authors.affiliation: Neurologic Clinic, Aeginition Hospital, 72-74, Vass. Sofias Ave. 11528, Athens, Greece. ekarariz@med.uoa.gr
authors.forename: Evangelia
authors.initials: E
authors.lastname: Kararizou
authors.forename: Panagiota
authors.initials: P
authors.lastname: Manta
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Kalfakis
authors.forename: Demetrios
authors.initials: D
authors.lastname: Vassilopoulos
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000473:pathology*; D001284:Atrophy; D001706:Biopsy; D006801:Humans; D008297:Male; D008875:Middle Aged; D018485:Muscle Fibers, Skeletal / Q000473:pathology; D018482:Muscle, Skeletal / Q000473:pathology*; D055815:Young Adult