The effects of a gluteus medius training protocol on muscle activation.

Context: Researchers have suggested that a weak or dysfunctional gluteus medius (GM) has been linked to a number of lower extremity injuries. Identifying an appropriate intervention to prevent or correct deficits of the GM and determine associated outcomes has become a subject of increased interest. Objective: To determine if GM training changes lower extremity muscle activation during a dynamic task. Design: Controlled laboratory study Setting: Biomechanics research laboratory. Participants: Eighteen healthy, physically active participants (7 men, 11 women; age = 21.2±2.01yrs; height = 168.39±8.92cm; mass= 77.76±16.39kg) volunteered for the study. All participants served as their own control. Intervention(s): All of the participants completed a six week GM training protocol. Muscle activation of 5 trunk muscles were measured bilaterally before and after the protocol during a single-leg drop landing and normalized. Main Outcome Measure(s): Peak and mean muscle activation was measured 400ms pre- and post-landing. Results: Decreased muscle activation was observed in the right GM [pre-mean (P=.001), pre-peak (P=.007), post-mean (P=.033), and post-peak (P=.045)]. Increased biceps femoris (BF) mean muscle activation was observed on the stance leg pre-landing (p=.044). Conclusions: Six weeks of GM training was enough time to observe improved GM neuromuscular efficiency. The increased BF muscle activation prior to landing suggests participants had an increased feedforward response in preparation for landing. Therefore the combination of improved neuromuscular efficiency and a greater feedforward response suggest pelvic stabilization may be improved during a single-leg drop landing as a result of six weeks of GM training.Department of applied sciences and rehabilitation.MJ GageILL-ETD-01