(11) EFFECT OF THE CONTINUOUS JUMP TEST ON DORSAL EXTENSION STRENGTH

Purpose: Determine the effect of the continuous jump test on dorsal extension strength.

Methods: Descriptive original research¹. With a sample of 13 physical education students from a public university in Rio de Janeiro, Brazil, aged 22,92±1,61 years old, body mass of 75,58±10,20 (kg), and height 174,65±6,18 (cm). Initially, they performed the pre-experimental condition in the dorsal extension isometric strength test (TFIED) with a validated analog dynamometer Crown Dorsal-200kg². Subjects were instructed to perform maximum back extension strength for 5 seconds. Three attempts of each test were performed with a 2-minute interval and the best performance was considered for analysis³. The experimental protocol of the continuous jump test is to perform the maximum number of continuous vertical jumps for 30 seconds, starting from the standing position, performing a countermovement to then perform the jump⁴, using the validated VERT JUMP monitor where height is measured by jumping repetitions⁵. Immediately afterwards, a TFIED retest was performed.

Results: Data are presented as mean, standard deviation, minimum and maximum value in table 1. The T test for dependent samples between pre-strength and post strength did not show significant differences p=0.171. The Anova test with Tukey's Post-Hoc determined that there is a significant difference between Last Jump and Best Jump p=0.00 and between Last and Average Height p=0.00.

Conclusions: It is possible to conclude that performing continuous jumps does not affect dorsal extension strength. However, it was clear that there is a significant reduction in jump performance during the test. PRACTICAL APPLICATIONS: Performing jumps for a short time interval does not affect the performance of dorsal extension strength. considering that it’s reduction of strength may represent loss of control and extension, allowing flexion that can increase the mechanical load on the spine. In this way, we can indicate that vertical jumps on the ground in sports and in exercises with little volume are safe.

Table 1. Results of continuous jump test and TFIED.

 



Acknowledgements: None