Τίτλος:
Muscle Fiber Conduction Velocity, Muscle Fiber Composition, and Power Performance
Γλώσσες Τεκμηρίου:
Αγγλικά
Περίληψη:
Purpose The aim of this study was to explore the relationship between muscle fiber conduction velocity (MFCV), fiber type composition, and power performance in participants with different training background. Methods Thirty-eight young males with different training background participated: sedentary (n = 10), endurance runners (n = 9), power trained (n = 10), and strength trained (n = 9). They performed maximal countermovement jumps (CMJ) and maximal isometric leg press for the measurement of the rate of force development (RFD). Resting vastus lateralis MFCV was measured with intramuscular microelectrodes on a different occasion, whereas muscle fiber type and cross-sectional area (CSA) of vastus lateralis were evaluated through muscle biopsies 1wk later. Results MFCV, CMJ power, RFD, and % CSA of type II and type IIx fibers were higher for the power-trained group (P < 0.001). No difference was found between sedentary participants and endurance runners in these variables, but both of these groups performed worse than strength/power participants. Close correlations were found between MFCV and fiber CSA as well as the % CSA of all fiber types as well as with RFD and CMJ power (r = 0.712-0.943, P < 0.005). Partial correlations revealed that the % CSA of IIx fibers dictates a large part of the correlation between MFCV and RFD, power performance. Significant models for the prediction of the % CSA of type IIa and type II as well as the CSA of all muscle fibers based upon MFCV, RFD, and CMJ were revealed (P = 0.000). Conclusion MFCV is closely associated with muscle fiber % CSA. RFD and jumping power are associated with the propagation of the action potentials along the muscle fibers. This link is regulated by the size and the distribution of type II, and especially type IIx muscle fibers. © 2016 by the American College of Sports Medicine.
Συγγραφείς:
Methenitis, S.
Karandreas, N.
Spengos, K.
Zaras, N.
Stasinaki, A.-N.
Terzis, G.
Περιοδικό:
MEDICINE AND SCIENCE IN SPORTS AND EXERCISE
Εκδότης:
Lippincott Williams and Wilkins
Λέξεις-κλειδιά:
adult; athlete; exercise; exercise test; human; male; muscle strength; physiology; quadriceps femoris muscle; sedentary lifestyle; skeletal muscle cell; young adult, Adult; Athletes; Exercise; Exercise Test; Humans; Male; Muscle Fibers, Skeletal; Muscle Strength; Quadriceps Muscle; Sedentary Lifestyle; Young Adult
DOI:
10.1249/MSS.0000000000000954
