The aim of this study was to explore the effects of simulated soccer match play on neuromuscular performance in adolescent players longitudinally over a two-year period. Eleven players completed all measurements in both years of the study (1st year: age 16.0 ± 0.4 y; stature 178.8 ± 6.4 cm; mass 67.5 ± 7.8 kg; maturity-offset 2.24 ± 0.71 y). There was a significant reduction in hamstring strength after simulated match by the soccer-specific aerobic field test (SAFT90), with four out of eight parameters compromised in U16s (4.7-7.8% decrease) and six in the U17s (3.1-15.4%). In the U17s all of the concentric quadriceps strength parameters were decreased (3.7-8.6%) as well as the vastus lateralis and semitendinosus firing frequency (26.9-35.4%). In both ages leg stiffness decreased (9.2-10.2%) and reactive strength increased pre to post simulated match (U16 8.0%; U17 2.5%). A comparison of changes between age groups did not show any differences. This study demonstrates a decrease in neuromuscular performance post simulated match play in both ages but observed changes were not age dependent.

• Klíčová slova
• EMG, isokinetic, leg stiffness, reactive strength, simulated match-play,
• MeSH
• dolní končetina * fyziologie   MeSH
• fotbal * MeSH
• kosterní svaly * fyziologie   MeSH
• lidé MeSH
• longitudinální studie MeSH
• mladiství MeSH
• svalová síla * fyziologie   MeSH
• Check Tag
• lidé MeSH
• mladiství MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The aim of this study was to examine the acute effects of soccer specific fatigue on muscular and neuromuscular function in male youth soccer players. Elite soccer players (n = 20; age 15.7 ± 0.5 y; body height 177.75 ± 6.61 cm; body mass 67.28 ± 8.29 kg) were measured before and after soccer specific exercise (SAFT90). The reactive strength index (RSI) was determined by a drop jump test, leg stiffness (LS) by a 20 sub-maximal two-legged hopping test, and a functional hamstring to quadriceps strength ratio from isokinetic concentric and eccentric strength of the dominant and non-dominant leg (measured at angular velocities of 1.05 rad · s-1 and 3.14 rad · s-1). Metabolic response to the SAFT90 was determined by blood lactate and perceived exertion was assessed by the Borg scale. After simulated match play, a significant decrease in absolute LS (t = 4.411; p < 0.001; ω2 = 0.48) and relative LS (t = 4.326; p < 0.001; ω2 = 0.49) was observed and the RSI increased significantly (t = 3.806; p = 0.001; ω2 = 0.40). A reduction in LS found after the SAFT90 indicates possible reduction in dynamic knee stabilization. However, if we consider the changes in other observed variables, the present study did not clearly confirm that fatigue induced by a soccer specific protocol increased the risk of ACL and hamstring injury. This may be attributed to the simulated rather than actual match play used in the present study.

• Klíčová slova
• ACL, isokinetic, leg stiffness, neuromuscular function, reactive strength,
• Publikační typ
• časopisecké články MeSH