Comparison of Electromyographic Activity of the Superior and Inferior Portions of the Gluteus Maximus Muscle During Common Therapeutic Exercises.
Level 4 - case-series / case-control
Within-subject cross-sectional physiological laboratory study
PubMed 27494053 · doi:10.2519/jospt.2016.6493
What was done
Twenty healthy participants performed 11 common therapeutic exercises. Fine-wire electromyography (EMG) recorded activity simultaneously from the superior and inferior segments of the gluteus maximus. Normalized EMG signal amplitudes were compared between both muscle regions across all 11 exercises using a 2-way repeated-measures analysis of variance.
What was found
The abstract does not report specific numerical EMG percentages, means, or p-values. It reports that the superior gluteus maximus had significantly higher relative EMG activity than the inferior portion in 5 of the 11 exercises, specifically those involving hip abduction and/or external rotation. In the remaining 6 exercises (predominantly hip extension), activation did not differ significantly between the two muscle portions.
Why it matters
These findings confirm that the gluteus maximus functions heterogeneously, allowing physical therapists to select specific exercises when preferential recruitment of the superior portion is desired.
Limits
The sample size was small (n = 20) and restricted to healthy individuals, which may not reflect activation patterns in patients with hip or lower back pathology. The study measured acute EMG amplitude rather than long-term strength or rehabilitation outcomes, and exact numerical results and effect sizes were omitted from the abstract.
Cited by
- supports Hip abduction movements specifically target and activate the gluteus medius and the upper fibers of the gluteus maximus.
- supports The gluteal muscles perform three primary actions: hip extension, hip abduction, and hip external rotation, as well as posterior pelvic tilt.