Correlation analysis of vertical jump variables in male track and field athletes

Abstract

Background: The purpose of this study is threefold: (1) compare differences in countermovement jump (CMJ) variables and squat jump (SJ) variables in male track and field athletes; (2) explore the correlation of Fast Twitch Fibers (FT), Effect of Pre-stretch (EP) and other variables during the CMJ in male track and field athletes; (3) explore the correlation of SJ variables in male track and field athletes. Methods: 96 male university athletes (21.25 ± 1.04 years; 71.96 ± 8.58 kg; 180.05 ± 5.66 cm) in track and field volunteered to participate in this study. They are from Capital University of Physical Education and Sports, and all athletes are above the national standard at the second level. Subjects sequentially completed 3 CMJs and 3 SJs on the force plate. Throughout the entire range of motion, the CMJ and SJ were performed with both hands on the hips. In a laboratory, all of the individuals were assessed at the same time. SPSS 25.0 (Chicago, IL, USA) was used to run independent samples t-test and Pearson correlation analysis. Results: The vertical jump displacement (VJD) (p < 0.01), squat displacement (SD) (p < 0.01), peak velocity (PV) (p < 0.01), peak power (PP) (p < 0.05), average power (AP) (p < 0.01) were significantly higher during the CMJ than during the SJ. The peak force (PF) (p < 0.01) was significantly smaller during the CMJ than during the SJ. The FT and EP during the CMJ were associated with low test-retest reliability (coefficient of variation (CV): 9.73–8.86%). VJD, SD, PF, PP, and AP produced high test-retest reliability (CV: 2.29–4.48%) during both the CMJ and SJ movements. The correlation results were as follows, the VJD during the CMJ was significantly related to SD, PF, PP, AP (r = 0.21, r = 0.42, r = 0.8, r = 0.69, respectively). The PF during the CMJ was significantly related to PP and AP (r = 0.87, r = 0.72, respectively). The PV during the CMJ was significantly related to PP and AP (r = 0.63, r = 0.79, respectively). During the CMJ, there were significant connections between PP and AP (r = 0.94). Except for SD showed no significant relationships and the results for the correlation of other variables were the same as CMJ during the SJ. Furthermore, the Fast Twitch Fibers (FT) during the CMJ was significantly related to PP and AP (r = 0.49, r = 0.46, respectively). The Effect of Pre-stretch (EP) during the CMJ was significantly related to PV, PP, AP and FT (r = 0.36, r = 0.24, r = 0.27, r = 0.22, respectively). Conclusions: Our results indicate that both FT and EP were highly significantly correlated with PP in CMJ, and both FT and EP were significantly correlated with AP in CMJ. In addition, FT and EP data have good reliability. It means that FT and EP may be important indicators of lower limb strength in male track and field athletes under certain conditions. This will inform the training of male track and field athletes.