Gluteus Medius Muscle Activation During Isometric Muscle Contractions

Abstract

Context: Functional subdivisions are proposed to exist in the gluteus medius (GM) muscle. Dysfunction of the GM, in particular its functional subdivisions, is commonly implicated in lower limb pathologies. However, there is a lack of empirical evidence examining the role of the subdivisions of the GM. Objectives: To compare the activation of the functional subdivisions of the GM (anterior, middle, and posterior) during isometric hip contractions. Design: Single-session, repeated-measures observational study. Setting: University research laboratory. Participants: Convenience sample of 15 healthy, pain-free subjects. Intervention: Subjects performed 3 maximal voluntary isometric contractions for hip abduction and internal and external rotation on an isokinetic dynamometer with simultaneous recording of surface electromyography (sEMG) activity of the GM subdivisions. Main Outcome Measures: sEMG muscle activity for each functional subdivision of the GM during each hip movement was analyzed using a 1-way repeated-measures ANOVA (post hoc Bonferroni). Results: The response of GM subdivisions during the 3 different isometric contractions was significantly different (interaction effect; P = .003). The anterior GM displayed significantly higher activation across all 3 isometric contractions than the middle and posterior subdivisions (main effect; both P < .001). The middle GM also demonstrated significantly higher activation than the posterior GM across all 3 isometric contractions (main effect; P = .027). There was also significantly higher activation of all 3 subdivisions during both abduction and internal rotation than during external rotation (main effect; both P < .001). Conclusions: The existence of functional subdivisions in the GM appears to be supported by the findings. Muscle activation was not homogeneous throughout the entire muscle. The highest GM activation was found in the anterior GM subdivision and during abduction and internal rotation. Future studies should examine the role of GM functional subdivisions in subjects with lower limb pathologies.

Effect of Hip Joint Position on Hip Abductor Muscle Activity during Lateral Step-up Exercises

“…In the present study, there was no significant difference in the EMG activity of the gluteus medius between HNP and HIRP (p>0.05). Interestingly, previous studies showed that gluteus medius activity was increased during hip internal rotation as well as hip abduction 21,22) . Researchers have shown that the gluteus medius has a role during hip internal rotation, although its main function is controlling hip movements in the frontal plane 22,23) .…”

“…Interestingly, previous studies showed that gluteus medius activity was increased during hip internal rotation as well as hip abduction 21,22) . Researchers have shown that the gluteus medius has a role during hip internal rotation, although its main function is controlling hip movements in the frontal plane 22,23) . O'Dwyer et al 22) investigated the effects of the direction of the hip isometric contraction on the activation of the gluteus medius and reported that the EMG activity of the gluteus medius was not significantly different during hip internal rotation and abduction due to the function of the gluteus medius in hip internal rotation.…”

“…Researchers have shown that the gluteus medius has a role during hip internal rotation, although its main function is controlling hip movements in the frontal plane 22,23) . O'Dwyer et al 22) investigated the effects of the direction of the hip isometric contraction on the activation of the gluteus medius and reported that the EMG activity of the gluteus medius was not significantly different during hip internal rotation and abduction due to the function of the gluteus medius in hip internal rotation. These previous studies help to explain why no significant differences were observed in gluteus medius activity between HNP and HIRP in our study.…”

EMG Analysis of Gluteus Medius Subdivisions during Modified Unilateral Biofeedback Exercises for the Lower Limbs

“…Only the activation of the anterior GM fiber increased as the load increased. O'Dwyer et al 20) compared the activation of the proposed functional subdivisions of GM during isometric contraction of the hip performed by normal subjects and determined the isometric hip contraction that caused the greatest GM activation. Their results indicate that the anterior fiber was activated the most by all exercises.…”

Gluteus Minimus and Gluteus Medius Muscle Activity During Common Rehabilitation Exercises in Healthy Postmenopausal Women

“…39 A major limitation of these studies is the use of surface electrodes to record activity of the GMed. 5,32,33,39,41 Surface electrode signals of middle GMed activity are known to be susceptible to cross-talk from surrounding muscles, 46 and it is not possible to record activity from the anterior and posterior portions of the GMed, given their deep anatomical location. 45 Another limitation of these studies is that they typically evaluated gluteal function in young, often healthy populations, 39 which limited the generalizability of their findings to older adults, in whom gluteal atrophy is common.…”