Biomechanics of backstroke start in elite swimmers: examining the relationship between posture, dynamic balance, and vertical jump performance

This study aimed to investigate the relationship between the kinematic parameters of swimmers' backstroke start performance and their dynamic balance, vertical jump, and postural characteristics. Seven elite male (n = 9) backstroke swimmers (FINA score: 711 ± 22.51) participated in the study, which consisted of four sessions. In the first session, swimmers performed two trials to familiarize themselves with the starting platform. In the second session, backstroke start kinematics were recorded using a stabilized GoPro10 Cam System and a DACTRONICS HS-200 Starting System, and analyzed using Kinovea 0.9.5 software. In the third session, dynamic balance (DB) was measured with the TecnoBody PK200 device, and vertical jump (VJ) performance was assessed with the Microgate Witty Wireless Timer. In the fourth session, posture was evaluated using the Apecs Posture Analysis Pro Plus 8.2.6 and the New York Posture Assessment (NYPA) method. Pearson correlation analysis revealed significant associations between PT-Anterior and HIPA (r = 0.667, p = 0.035), PT-Posterior and V (r = 0.703, p = 0.023), NYPA and WEH (r = - 0.663, p = 0.037), and PL-DB and WEH (r = - 0.721, p = 0.019). However, none of these associations remained statistically significant after the Benjamini-Hochberg false discovery rate (FDR) correction. In addition, no significant associations were observed between VJ performance and any of the kinematic parameters either before or after FDR correction. In conclusion, although potential associations were observed between postural characteristics, dynamic balance, and specific components of backstroke start kinematics, these associations were not confirmed following correction for multiple comparisons. Therefore, the findings should be interpreted as exploratory in nature.