Contributions of muscle biopsy to sport training

Abstract

Needle muscle biopsy is a relatively simple and safe technique that has been used to study the different muscles fiber types, their metabolic potential and capacity to adapt to a variety of training stimuli. Although fiber type is genetically determined, some characteristics of the fibers, including reversible changes in fiber subtypes, can be modeled by physical training and other factors related to life style. The fine and selective adaptation of enzyme levels, capillary supply and energy substrates to training is remarkable, as well as the close links between fiber type, energetic mechanisms and performance in physical exercises of different intensity and duration. The information obtained by the study of the muscle biopsy in sport practicing subjects has allowed the selection of the athletic specialty that it better suited to their muscle characteristics, to design a precise and scientifically based training program, to adjust it during training, and to try to obtain the best of the genetic potential of the subject. However, individual differences and the varied patterns of adaptation to exercise training is still an open field for the study of muscle characteristics by the muscle biopsy technique.