Modified Reactive Strength Index in Adolescent Athletes Competing in Different Sports and Its Relationship with Force Production

Leonidas Petridis^1, , Zsófia Tróznai¹, Gergely Pálinkás¹, Irina Kalabiska¹ and Tamás Szabó¹

¹Sport Science and Diagnostic Laboratory, University of Physical Education, Budapest, Hungary

Cite this paper

Leonidas Petridis, Zsófia Tróznai, Gergely Pálinkás, Irina Kalabiska and Tamás Szabó. Modified Reactive Strength Index in Adolescent Athletes Competing in Different Sports and Its Relationship with Force Production. American Journal of Sports Science and Medicine. 2017; 5(2):21-26. doi: 10.12691/AJSSM-5-2-2

Abstract

The modified reactive strength index (RSImod) is used as a measurement of reactive strength and explosiveness. The main purpose of the current study was to assess RSImod in young athletes competing in various sports and to examine the relationship between RSImod and eccentric and concentric force and vertical displacement. Two-way ANOVA showed a significant main effect for sport group, but not for age group. Soccer (0.47±0.09 m/s) and basketball players (0.49±0.1 m/s) had significantly higher values than handball players (0.36±0.07 m/s) and rowers (0.35±0.07 m/s). Among the independent variables, average eccentric force had the strongest relationship with RSImod. In conclusion, RSImod differs between athletes from different sports, but not between athletes from different age groups in the examined age period. Also, RSImod is strongly associated mainly with the average eccentric force and secondarily with the average concentric force during the countermovement jump.

Keywords

countermovement jump, power, junior athletes, eccentric and concentric force

Copyright

This work is licensed under a Creative Commons Attribution 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/

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