Author(s): JOHNSTON, T., BROWN, S., KALIARNTAS, K., Institution: EDINBURGH NAPIER UNIVERSITY , Country: UNITED KINGDOM, Abstract-ID: 814

INTRODUCTION:
Females are at greater risk than other populations to sustain a noncontact injury especially the knee, hamstring and ankle (Lin et al., 2018). This may be, in part, associated with muscle activation, landing technique leading to greater ligament strain via higher ground reaction force (Hewett et al., 2010). Multi-component neuromuscular training can significantly reduce noncontact injury (Brunner et al., 2019) by altering muscle activation, significantly reducing injuries and modifying landing technique (Zebis et al., 2016; Steinberg et al., 2017; Khayambashi et al., 2015 respectively). The aim of this study was to assess the effects of a sport-specific neuromuscular training programme (NMTP) on EMG, kinematics and kinetics during a sagittal plane hop, hop and twist and an unanticipated sidecut.
METHODS:
This controlled-trial with female recreational hockey players who either performed the NMTP or their usual warm-up (CON = 18, INT = 20). The intervention (INT) performed the NMTP 3x/week before their training sessions or matches for 8 weeks. The control (CON) group performed their normal warm-up at all times. The players were biomechanically tested (3-D motion capture system, force plates and electromyography (EMG)) while performing sagittal plane hop, hop and twist and an unanticipated sidecut each time. The EMG activity was measured Gluteus Maximus (GMax), Gluteus medias (GMed), Semitendinosus (HamMed), Biceps Femoris (HamLat), Vastus Medialis (VM) and Lateralis (VL), Gastrocnemius Lateralis (GasLat) and Medialis (GasMed) at 100ms and 30ms prior to initial contact (IC), 50ms post landing, IC to maximum knee flexion (MKF) and time to peak. Peak vertical ground reaction force (PvGRF), rate of force development (RFD) and trunk, hip, knee and ankle kinematics in all 3 planes was also measured.
RESULTS:
EMG: There was a non-statistically significant trend of greater muscle activation in all time points following NMT. There was significantly greater gastrocnemius (medialis and lateralis) muscle activation in both groups at 100ms prior to IC, IC to 50ms and IC to MKF, with a greater increase in the INT group. Further, there was an overall greater reduction in time to peak in INT compared to CON. Kinematics: There were significant decreases (p = 0.009) in maximum knee abduction (CON = 9.89 to 9.93°; INT = 10.89 to 8.47°) and knee excursion (p = 0.011) for INT (CON = 10.07 to 11.3°; INT = 10.79 to 8.04°). Kinetics: There was significant reduction (p= 0.002) in RFD (CON = 19.53 to 21.75; INT = 18.88 to 12.83 BW/s) after the intervention period for the intervention group.
CONCLUSION:
The sports-specific NMTP showed some significant alterations on the kinematics and kinetics following 8 weeks of NMT. There were significantly greater increases in the muscle activation of the Gastrocnemius for INT groups than CON. There were significant reductions in knee abduction and excursion and rate of force development following this NMTP. These adaptations could reduce the risk of injury.