POSITION-SPECIFIC DIFFERENCES IN FORCE-VELOCITY PROFILE AND CHANGE OF DIRECTION PERFORMANCE: A STUDY ON THE U-21 CZECH FOOTBALL PLAYERS
| Autoři | |
|---|---|
| Rok publikování | 2025 |
| Druh | Konferenční abstrakty |
| Fakulta / Pracoviště MU | |
| Citace | |
| Popis | INTRODUCTION: Force-velocity profile (FVP) measures an athletes ability to generate force and speed during movements like sprints. In soccer, sprinting and change of direction (COD) are crucial for both attacking and defensive actions. These performance may vary based on player’s position (e.g., forwards, defenders and midfielders). This study examines the differences in FVP and COD parameters across different positions in a U-21 soccer players. METHODS: Fifteen professional male U21 Czech National team soccer players participated, categorized by positions: forwards (n = 5), defenders (n = 5) and midfielders (n = 5). Player performed a 40-meter linear sprint and the COD test using the 1080 Sprint system (1080 Motion AB, Sweden). FVP parameters were assessed using the linear sprint with a 3 kg isotonic resistance, analyzing theoretical maximum force (F0), theoretical maximum velocity (V0), and maximal power output (Pmax). Each player completed three trials, with best attempt used for analysis. COD performance was measured using a modified 15-0-5 protocol, assessing maximal acceleration (MaxAcc) and maximal deceleration (MaxDec). Players performed two trials for each turning direction (right and left leg), with the best attempt analyzed. Position differences were evaluated using the delta percentage (?%) and Cohens d effect. RESULTS: Midfielders had highest F0 (8.04 ± 0.41 N/kg), which was 5.27% greater than defenders (7.62 ± 0.34 N/kg) with a large effect (Cohen d = 1.13). Forwards presented greatest V0 (9.65 ± 0.40 m·s-1), 3.94% higher than defenders (9.27 ± 0.47 m·s-1) and 4.04% greater than midfielders (9.26 ± 0.27 m·s-1), with a larger effect (Cohen d = 0.86 – 1.15). In the COD test, midfielders exhibited better performance, achieving 8.10% higher MaxAcc (7.63 ± 0.74 m·s-2) and 7.39% higher MaxDec (9.42 ± 0.76 m·s-2) compared to forwards (MaxAcc = 7.06 ± 0.85 m·s-2, MaxDec = 8.77 ± 0.60 m·s-2, respectively), with moderate to large effects (Cohen d = 0.72 - 0.94). CONCLUSION: This study that U21 Czech soccer players demonstrated position-specific differences in FVP and COD performance. Midfielders demonstrated higher F0, MaxAcc and MaxDec, reflecting the importance of agility and change direction actions for it position. Forwards excelled on V0 supporting their role in making faster dashes behind the defense and exploiting spaces in the offensive phase. These findings may be valuable for developing specific training programs that focus on enhancing the parameters most relevant to each position. |