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.

• Keywords
• EMG, isokinetic, leg stiffness, reactive strength, simulated match-play,
• MeSH
• Lower Extremity * physiology   MeSH
• Soccer * MeSH
• Muscle, Skeletal * physiology   MeSH
• Humans MeSH
• Longitudinal Studies MeSH
• Adolescent MeSH
• Muscle Strength * physiology   MeSH
• Check Tag
• Humans MeSH
• Adolescent MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

Many hamstring injuries that occur during physical activity occur while the muscles are lengthening, during eccentric hamstring muscle actions. Opposite of these eccentric hamstring actions are concentric quadriceps actions, where the larger and likely stronger quadriceps straighten the knee. Therefore, to stabilize the lower limbs during movement, the hamstrings must eccentrically combat against the strong knee-straightening torque of the quadriceps. As such, eccentric hamstring strength expressed relative to concentric quadricep strength is commonly referred to as the "functional ratio" as most movements in sports require simultaneous concentric knee extension and eccentric knee flexion. To increase the strength, resiliency, and functional performance of the hamstrings, it is necessary to test and train the hamstrings at different eccentric speeds. The main purpose of this work is to provide instructions for measuring and interpreting eccentric hamstring strength. Techniques for measuring the functional ratio using isokinetic dynamometry are provided and sample data will be compared. Additionally, we briefly describe how to address hamstring strength deficiencies or unilateral strength differences using exercises that specifically focus on increasing eccentric hamstring strength.

• MeSH
• Quadriceps Muscle physiology   MeSH
• Adult MeSH
• Muscle, Skeletal physiology   MeSH
• Humans MeSH
• Resistance Training methods   MeSH
• Sports physiology   MeSH
• Exercise Therapy methods   MeSH
• Check Tag
• Adult MeSH
• Humans MeSH
• Male MeSH
• Publication type
• Video-Audio Media MeSH
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH