Combined effects of lower limb muscle fatigue and decision making to the knee joint during cutting maneuvers based on two different position-sense-acuity groups

Abstract

Research concerning the combined effect of fatigue and decision making was still insufficient to fully understand the ACL injury mechanism. A controlled laboratory experiment was conducted in which 14 volunteered healthy collegiate males participated and were instructed to perform jumping followed by cutting maneuver under four simulated circumstances, i.e., pre-fatigue anticipated, pre-fatigue unanticipated, post-fatigue anticipated, and post-fatigue unanticipated. Significant increase of knee extension, valgus, and internal rotation moment as well as peak proximal tibia anterior shear force were observed after fatigue. However, only increased knee extension moment and peak proximal tibial anterior shear force were found when the task was activating by unanticipated stimulus. Knee extension and internal rotation moments together with tibial anterior shear force were magnified under post-fatigue unanticipated condition. These findings suggested that interaction effect between fatigue and decision making may restrain the sensory sensitivity of peripheral movement receptors surrounding lower extremity, resulting in decreased proprioceptive capability.