Biomaterial Database

Capillary supply of skeletal muscle fibers in untrained and endurance-trained men. 1977

P Brodal, and F Ingjer, and L Hermansen

Muscle fiber diameters and numbers of capillaries per fiber, per square millimeter, and around each fiber were determined in needle biopsies from the lateral part of the quadriceps muscle of 23 young men. Twelve subjects were untrained (UT) and eleven were endurance-trained (ET) athletes. Average values for maximal oxygen uptake were 51.3 (UT) and 72.0 ml/kg-min (ET). Mean fiber diameters were not significantly different in the two groups (48.8 and 49.1 micron). The capillaries per fiber ratios were 1.77+/-0.10 and 2.49+/-0.08 (mean+/-SE) in the UT and ET groups, respectively. The numbers of capillaries around each fiber were 4.43+/-0.19 (UT) and 5.87+/-0.18 (ET). The numbers of capillaries per mm2 were 585+/-40 (UT) and 821+/-28 (ET). Fiber diameters were 28% smaller in ultrathin than in fresh-frozen sections from the same biopsies. After correction for this difference, the numbers of capillaries per mm2 were 305 and 425 in the UT and ET, respectively. The capillaries per fiber ratio increased with increasing fiber diameter, but not sufficiently to maintain the number of capillaries per mm2. Fibers containing many mitochondria are surrounded by more capillaries than fibers with few mitochondria.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
D008931	Mitochondria, Muscle	Mitochondria of skeletal and smooth muscle. It does not include myocardial mitochondria for which MITOCHONDRIA, HEART is available.	Sarcosomes,Mitochondrion, Muscle,Muscle Mitochondria,Muscle Mitochondrion,Sarcosome
D009132	Muscles	Contractile tissue that produces movement in animals.	Muscle Tissue,Muscle,Muscle Tissues,Tissue, Muscle,Tissues, Muscle
D010807	Physical Endurance	The time span between the beginning of physical activity by an individual and the termination because of exhaustion.	Endurance, Physical,Physical Stamina,Stamina, Physical
D002196	Capillaries	The minute vessels that connect arterioles and venules.	Capillary Beds,Sinusoidal Beds,Sinusoids,Bed, Sinusoidal,Beds, Sinusoidal,Capillary,Capillary Bed,Sinusoid,Sinusoidal Bed
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000293	Adolescent	A person 13 to 18 years of age.	Adolescence,Youth,Adolescents,Adolescents, Female,Adolescents, Male,Teenagers,Teens,Adolescent, Female,Adolescent, Male,Female Adolescent,Female Adolescents,Male Adolescent,Male Adolescents,Teen,Teenager,Youths
D000328	Adult	A person having attained full growth or maturity. Adults are of 19 through 44 years of age. For a person between 19 and 24 years of age, YOUNG ADULT is available.	Adults