RESUMO
Morphometrical characteristics of the skeletal muscle fibers of the m. vastus lateralis has been presented in the skaters of a high qualification. The muscle biopsies have been obtained by means of the needle biopsy method from 5 sprinters and 10 classical all-round competitors. Longitudinal sections of the peripheral and central parts of the muscle fiber have been investigated, subdividing the fibers in accordance with certain ultrastructural criteria into two types: slow and fast. The area of mitochondria, myofibrils, lipid inclusions has been determined by means of the system of the image analysis ACM-68K (Leitz, BRD). To the defining factors in the skater muscle ultrastructure, influencing the level of sporting achievements, a high parameter of the volumetric density of the whole mitochondrial population (7.6% in the sprinters and 9.2% in the all-around competitors) and an exceptionally high parameter of the sarcoplasmic density (28.5% in the sprinters and 36% in the all-around competitors) should be ascribed. The morphometrical data of the skaters muscle fiber are compared with the muscle parameters (according to the literature data) of the m. vastus lateralis in high qualification sportsmen of other specialization and in nontrained persons.
