Drop jump improved RSA performance but not changed neuromuscular parameters in young basketball players

Author(s)

Gabriel Machado Claus

• Document type: Master's Dissertation
• Press: Bauru. 2019-10-21.
• Institution: Universidade Estadual Paulista (Unesp). Faculdade de Ciências. Bauru
• Defense date: 2019-09-06
• Advisor: Alessandro Moura Zagatto

Abstract

Repeated sprint efforts have been identified as a key component of physical fitness in team sports, such basketball. The high intensity efforts required throughout the game will generate fatigue, and the inability to maintain initial velocity/force levels, thus, decreasing performance and hence instituting muscle fatigue. A strategy to improve performance can be post-activation potentiation (PAP). PAP is defined as enhanced involuntary twitch in response of a prior voluntary contraction and has been inserted into the warm-up routine leading to improved performance. In addition, specific PAP application to mode of exercise showed better results than a PAP non-specific to sport. Therefore, the objective of this present study was to investigate the effect of two specifics PAP protocols on performance in repeated sprint efforts with changes on direction in basketball players and in fatigue manifestation. Ten basketball players (age: 17,5 ± 1,2 years; height: 1,9 ± 0,1 m; weight: 87,2 ± 15,4 kg; competitive experience: 5,2 ± 1,5 years) were selected and participated in randomized cross over mode experimental procedures. Initially, the volunteers were familiarized with the procedures, in the next visits of evaluations the volunteers were submitted to a standardized warm-up, identical in all the conditions. After warming up, neuromuscular measurements were performed, consisting of 2 contractions voluntary maximal isometric of knee extension with electrical stimuli and monitoring of the electromyography responses, then the athletes were submitted to the conditioning protocols (heavy sled sprint and drop jump) or control condition. After 4 minutes for drop jump or 8 minutes for heavy sled sprint of the end of the experimental protocol the performance in the RSA test was measured, and immediately after the end of the RSA test the neuromuscular measurements were performed. Also, the surface electromyography signal of the dominant leg muscles was monitored during the RSA test. Significant interaction was found for the mean time (p = 0.033, post hoc p = 0.039), total time (p = 0.031, post hoc p = 0.037) and worst time (p = 0.029, post hoc p = 0.045), with the DJ condition showing improvement compared to the control condition. However, no significant interaction was found between the results in the neuromuscular evaluations, only alteration was found in comparison to the moments before and after the RSA test for all conditions. Also, no significant interaction was found between the conditions for the results in monitoring the electromyography responses during the sprints. Therefore, the use of the DJ conditioning effort was effective to induce the improvement of the physical performance in the RSA test in basketball athletes, yet, the RSA test induced participation of the peripheral and central parameters in a similar way between the conditions independent of the performanc (AU)

• FAPESP's process: 17/14187-6 - Effect of specific post-activation potentiation protocols on performance in repeated sprint efforts with change of direction and fatigue measurement in basketball athletes
• Grantee: Gabriel Machado Claus
• Support Opportunities: Scholarships in Brazil - Master