Verbal instructions affect reactive strength index modified and time-series waveforms in basketball players

Sánchez-Sixto, A ORCID:, McMahon, JJ ORCID: and Floría, P ORCID: 2021, 'Verbal instructions affect reactive strength index modified and time-series waveforms in basketball players' , Sports Biomechanics , pp. 1-11.

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This study aimed to determine the effects of different verbal instructions, intended to affect the countermovement jump (CMJ) execution time, on the reactive strength index modified (RSI ) and the time-series waveforms. Thirteen male basketball players performed six CMJs on a force plate with two different verbal instructions: 'jump as high as possible' (CMJhigh) and 'jump as high and as fast as possible' (CMJfast). Force-, power-, velocity-, and displacement-series waveforms, RSI and jump height were compared between conditions using statistical parametric mapping procedures. CMJfast showed greater values in RSI ( = 0.002) despite no differences in jump height ( = 0.345). Unweighting force (between 18% and 33% of total time) was lower in the CMJfast compared to CMJhigh. Larger force (between 53% and 63% of total time), velocity (between 31% and 48% of total time) and power (between 43% and 56% of total time) were found in the CMJfast compared to CMJhigh. These findings suggest that commanding athletes to jump as high and fast as possible increases rapid force production. Additionally, the results highlight the relevance of the countermovement phase in jumping and show that RSI could increase without power output modifications during propulsion, despite previous studies having reported positive associations between RSI propulsion power.

Item Type: Article
Additional Information: ** From PubMed via Jisc Publications Router **Journal IDs: eissn 1752-6116 **Article IDs: pubmed: 33404374 **History: published 06-01-2021
Schools: Schools > School of Health and Society
Journal or Publication Title: Sports Biomechanics
Publisher: Taylor & Francis
ISSN: 1476-3141
Related URLs:
SWORD Depositor: Publications Router
Depositing User: Publications Router
Date Deposited: 15 Apr 2021 10:07
Last Modified: 27 Aug 2021 21:49

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