Τίτλος:
FIBER TYPE COMPOSITION AND RATE OF FORCE DEVELOPMENT IN ENDURANCE- AND RESISTANCE-TRAINED INDIVIDUALS
Γλώσσες Τεκμηρίου:
Αγγλικά
Περίληψη:
The purpose of the study was to investigate the relationship between muscle fiber composition and the rate of force development (RFD) in well-trained individuals with different training background. Thirty-eight young men with different training background participated: 9 endurance runners, 10 power-trained individuals, 9 strength-trained individuals, and 10 sedentary individuals. They performed maximal isometric leg press for the measurement of RFD. Body composition (dual x-ray absorptiometry) and vastus lateralis fiber type composition were also evaluated. When all participants were examined as a group, moderate correlations were found between the percent of type II muscle fibers and RFD between 100 and 600 milliseconds (r = 0.321-0.497; p ≤ 0.05). The correlation coefficients were higher for the cross-sectional area (CSA) and the %CSA of type II and IIx muscle fibers (r = 0.599-0.847; p , 0.001). For the power group, RFD up to 250 milliseconds highly correlated with % type IIx muscle fibers and type IIx fiber CSA (r = 0.670-0.826; p ≤ 0.05), as well as with %CSA of type IIx fibers (r = 0.714-0.975; p ≤ 0.05). Significant correlations were found between the relative RFD ($kg21 lower extremities lean mass) and CSA-%CSA of type II and IIx fibers for the power group (r = 0.676-0.903; p ≤ 0.05). No significant correlations were found between muscle morphology and RFD for the other groups. In conclusion, the present data suggest that there is a strong link between the type IIx muscle fibers and early RFD and relative RFD in powertrained participants. Type II fibers seem to be moderately linked with RFD in non-power-trained individuals. © 2019 NSCA National Strength and Conditioning Association. All rights reserved.
Συγγραφείς:
Methenitis, S.
Spengos, K.
Zaras, N.
Stasinaki, A.-N.
Papadimas, G.
Karampatsos, G.
Arnaoutis, G.
Terzis, G.
Περιοδικό:
Journal of strength and conditioning research
Εκδότης:
NSCA National Strength and Conditioning Association
Λέξεις-κλειδιά:
adult; body composition; cytology; endurance training; fast muscle fiber; human; male; muscle isometric contraction; muscle strength; physiology; quadriceps femoris muscle; resistance training; running; weight lifting; young adult, Adult; Body Composition; Endurance Training; Humans; Isometric Contraction; Male; Muscle Fibers, Fast-Twitch; Muscle Strength; Quadriceps Muscle; Resistance Training; Running; Weight Lifting; Young Adult
DOI:
10.1519/JSC.0000000000002150
