Vpliv višine ovir na spremenljivke odrivne moči pri zaporednih navpičnih poskokih : magistrsko delo

Lončar, Nejc (author), Štirn, Igor (mentor), Spudić, Darjan (comentor)

Cilj magistrske naloge je bil preučiti vpliv višine ovir na mehanske, časovne in kinematične spremenljivke pri zaporednih sonožnih preskokih ovir. Glavni namen raziskave je bil ugotoviti, do katere višine lahko športniki še ohranjajo kratek kontaktni čas (okoli 180 ms), ki je značilen za razvoj reaktivne moči, ter kako se pri povečevanju višine ovir spreminja tehnika poskoka. Raziskava je temeljila na predpostavki, da višja kot je ovira, večje prilagoditve tehnike poskokov so potrebne, kar lahko vpliva na učinkovitost pliometrične vadbe. V raziskavi je sodelovalo 17 študentov Fakultete za šport, ki usmerjajo predmet atletika (povprečna starost 24,4 ± 5,4 leta). Uporabili smo tenziometrično ploščo (model 9287A, Kistler, Winterthur, Švica) za zajem mehanskih in časovnih spremenljivk (višina skoka, kontaktni čas, vertikalni pospešek v ekscentrični in koncentrični fazi, hitrost zaviranja in odriva v horizontalni smeri) ter visokofrekvenčne kamere Panasonic DMC-FZ200 (Panasonic corporation, Kadoma, Osaka, Japonska) za videoanalizo v sagitalni ravnini, s katero smo analizirali kinematične spremenljivke (naklon trupa, kot v gležnju, kolenu in kolku). Višine ovir, ki so jih športniki preskakovali so bile 0,15 m, 0,30 m, 0,45 m, 0,60 m in 0,75 m, in smo jih spreminjali v naključnem vrstnem redu. Statistično analizo smo izvedli s programsko opremo IBM SPSS Statistic 29 (IBM Corporation, New York, ZDA). Za primerjavo odvisnih spremenljivk (višina skoka, kontaktni čas, vertikalni pospešek, hitrost odriva) glede na višino ovire in kinematičnih spremenljivk smo uporabili enosmerno analizo variance (angl. One way ANOVA) in Bonferronijev test za primerjave med višinami (post-hoc test). Ugotovili smo, da med posameznimi višinami ovir ni bilo statistično značilnih razlik v višini skoka, kontaktnem času in vertikalnem pospešku, vendar so se pojavili jasni trendi. Z višanjem ovir se je kontaktni čas športnikov podaljšal (z 0,177 s na 0,191 s), vertikalni pospešek pa se je zmanjšal, kar nakazuje na zmanjšano učinkovitost elastičnih komponent. Statistično značilne spremembe so se pojavile pri kinematičnih spremenljivkah v točki prehoda čez oviro: povečal se je naklon trupa (s 6,4° na 33,8°) ter kot v kolenu (s 14,5° na 106,0°) in kolku (iz 13,5° na 113,9°). To kaže, da višje ovire zahtevajo izrazite tehnične prilagoditve v fazi leta, medtem ko tehnika pri odrivu in pristanku ostaja nespremenjena.

• Language: Slovenian
• Keywords: pliometrična vadba, reaktivna moč, kontaktni čas, višina ovir
• Work type: Master's thesis/paper
• Typology: 2.09 - Master's Thesis
• Organization: FŠ - Faculty of Sport
• Year: 2025
• PID: 20.500.12556/RUL-174543
• COBISS.SI-ID: 258254339
• Publication date in RUL: 04.10.2025

Secondary language

• Language: English
• Title: THE INFULENCE OF HURDLE HEIGHT ON PROPULSIVE POWER VARIABLES IN CONSECUTIVE VERTICAL JUMPS

Abstract

The aim of this master’s thesis was to examine the effect of hurdle height on mechanical, temporal, and kinematic variables during consecutive vertical jumps. The main objective was to determine the maximum hurdle height at which athletes are still able to maintain a short ground contact time (approximately 180 ms), which is characteristic of reactive strength performance, and to investigate how jump technique changes with increasing hurdle height. The study was based on the assumption that higher hurdles require greater technical adaptations, which may affect the efficiency of plyometric training. The research sample consisted of 17 students from the Faculty of Sport, all of whom had completed coursework in athletics (mean age: 24.4 ± 5.4 years). A force plate (model 9287A, Kistler, Winterthur, Switzerland) was used to collect mechanical and temporal data (jump height, ground contact time, vertical acceleration in the eccentric and concentric phases, braking and take-off speed in the horizontal direction). A high-frequency video camera (Panasonic DMC-FZ200, Panasonic Corporation, Kadoma, Osaka, Japan) was used for 2D sagittal plane analysis of kinematic variables (trunk lean, and angles at the ankle, knee, and hip joints). The hurdle heights were 0.15 m, 0.30 m, 0.45 m, 0.60 m, and 0.75 m, presented in a randomized order. Statistical analysis was performed using IBM SPSS Statistics 29 (IBM Corporation, New York, USA). To compare dependent variables (jump height, ground contact time, vertical acceleration, and take-off speed) between hurdle heights, a one-way ANOVA was used along with Bonferroni post-hoc tests. The results showed no statistically significant differences in jump height, ground contact time, or vertical acceleration across hurdle heights, although clear trends were observed. As hurdle height increased, contact time increased (from 0.177 s to 0.191 s), and vertical acceleration decreased, indicating reduced elastic response efficiency. Statistically significant differences were found in kinematic variables during hurdle clearance: trunk lean increased (from 6.4° to 33.8°), as did the knee angle (from 14.5° to 106.0°) and hip angle (from 13.5° to 113.9°). These findings suggest that higher hurdles require pronounced technical adaptations during the flight phase, while take-off and landing mechanics remain unaffected.

• Keywords: plyometric training, reactive strength, ground contact time, hurdle height