LE3 .A278 2011

2011

Landry, Scott

Acadia University

Bachelor of Kinesiology

Honours

Kinesiology

Kinesiology

Non-contact ACL injuries occur approximately 40 milliseconds after initial contact with the ground during landing or cutting movements and injury risk is 2-8 times greater in females. The purpose of the study was to use EMG to compare neuromuscular control patterns of 6 lower extremity muscles in elite soccer players during the pre- and post-contact phases of an unanticipated sidecut maneuver performed on artificial turf. Muscles were analyzed i) for differences between gender, and ii) for differences between an audio and visual cue for the unanticipated maneuvers. A gender difference was identified in the pre-contact phase for the bicep femoris as females demonstrated lower neuromuscular activity. In response to an audio cue, lower levels of muscle activity were generated in the pre-contact phase of the sidecut for the lateral gastrocnemius, semitendinosus/ semimembranosus (MH) and vastus lateralis. A timing difference in the post-contact phase for the MH was also identified between the two cues. These results suggest that in comparison to a visual cue, a player’s response to an audio cue may leave them more susceptible to ACL injury as important knee joint stabilizer muscles were not activated to comparable levels. Understanding neuromuscular control patterns is important to design preventative training regimes, particularly in females, as this injury often leads to accelerated osteoarthritis at the knee and requires invasive surgery for the athlete to return to sport.

The author retains copyright in this thesis. Any substantial copying or any other actions that exceed fair dealing or other exceptions in the Copyright Act require the permission of the author.

https://scholar.acadiau.ca/islandora/object/theses:775