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Tuesday, June 6, 2023

Electromyographic Analysis of Gluteus Maximus and Hamstring Activity During the Supine Resisted Hip Extension Exercise Versus Supine Unilateral Bridge to Neutral

Brent Brookbush

Brent Brookbush


Research Review: Electromyographic Analysis of Gluteus Maximus and Hamstring Activity During the Supine Resisted Hip Extension Exercise Versus Supine Unilateral Bridge to Neutral

By Jacky Au, PhD, CPT

Edited by Brent Brookbush DPT, PT, COMT, MS, PES, CES, CSCS, ACSM H/FS

Original Citation:

Youdas, J. W., Hartman, J. P., Murphy, B. A., Rundle, A. M., Ugorowski, J. M., and Hollman, J. H. (2017). Electromyographic analysis of gluteus maximus and hamstring activity during the supine resisted hip extension exercise versus supine unilateral bridge to neutral. Physiotherapy Theory and Practice33(2), 124-130. ABSTRACT


Multiple studies demonstrating the correlation between gluteus maximus inhibition and dysfunction have been cited in the Brookbush Institute's predictive models of Lower Extremity Dysfunction (LED) and Lumbopelvic Hip Complex Dysfunction (1, 2). This 2017 study by American researchers investigated relative gluteus maximus and hamstring  muscle activity during a single-leg glute-bridge (flexed knee bridge) and supine resisted hip extension (straight-leg bridge). Results demonstrated that the single-leg glute bridge resulted in a large increase in gluteus maximus activity without a subsequent increase in hamstrings activity, where as supine resisted hip extension resulted in similar increases in gluteus maximus and hamstring  activity.

Study Summary

Study DesignComparative, Observational Study
Level of EvidenceIII Evidence from non-experimental descriptive studies, such as comparative studies, correlation studies, and case-control studies.
Participant Characteristics



  • Mean Age:
    • Men: 23.4 +/- 1.3
    • Women: 23.5 +/- 1.2

  • Age Range:
    • Men: 22-26
    • Women: 22-27

  • Gender: 13 males, 13 females

Inclusion Criteria:

  • Between 20-39 years of age

Exclusion Criteria:

  • History of the following lower extremity conditions:
    • Subluxation
    • Dislocation
    • Fracture
    • Joint instability
    • Tendinitis
    • Bursitis
    • Impingement
    • Adhesive capsulitis
    • Neurovascular complications
    • Or any condition limiting physical activity for greater than two days over the previous six months

  • Current complaints of low back pain, or neuromuscular pain, numbness, or tingling in the low back or lower extremity.

Participants attended a single laboratory session. First, the maximal voluntary isometric contraction (MVIC) of their gluteus maximus and hamstrings were established using surface electromyography (EMG). Then, participants performed two different exercises: the single-leg glute bridge (flexed knee) and the supine resisted hip extension (straight leg), while EMG was recorded. Exercise induced muscle activation was normalized as a percentage of participants’ baseline MVIC, and the gluteus maximus/hamstrings ratio was compared for each exercise.

 Maximum Voluntary Isometric Contraction Measurements:

  • MVIC of the gluteus maximus was measured with the participant in a prone position with their knee flexed to 90° and their hip extended (thigh off of the table). The examiner attempted to push the participant’s thigh to the table by applying force to the distal posterior thigh.
  • MVIC of the hamstrings was measured with the participant in a prone position and their knee flexed to 45°. The examiner attempted to extend the leg by applying a downward force to their ankle as the participant resisted.

Single-leg Glute-Bridge

  • Participant lay supine with right knee flexed at 90 degrees and left knee extended.
  • Participant pressed the right foot against the ground to elevate the hips while maintaining alignment between the shoulder, hip, and knee.
  • The left hip was to remain level with the right hip, the left thigh was parallel with the right thigh, and left knee remained extended.
  • The top position was held for 10-seconds.

 Supine resisted hip extension exercise

  • The participant was in a supine position with hip, knees and ankles in alignment.
  • The participants’ right heel was then supported by the examiner.
  • The participant was instructed to maintain alignment between their low back and lower extremity (maintain neutral hip extension and terminal knee extension) as the examiner lifted their heel.
  • The examiner lifted the participants heel off of the table by approximately 90-centimetres (cm).
  • The top position resulted in the participant’s lower-back, hips and knees elevated above the table.
  • The top position was held for 5-seconds.
Data Collection and AnalysisElectromyography:
  • The gluteus maximus electrode was placed midway between the lateral edge of the sacrum and the posterior edge of the greater trochanter (3).
  • The hamstrings electrode was placed midway between the gluteal fold and the popliteal fossa (3).
  • EMG was collected using Bagnoli DE 3.1 double-differential surface sensors (Delsys, Inc., Boston, MA, USA).
  • Data were sampled at 1000 Hz and processed with EMG works® Data Acquisition and Analysis software (Delsys Inc.).

Data Analysis

The Wilcoxon signed-ranks non-parametric test was used to compare the following measurements:

Outcome Measures
ResultsGluteus Maximus Activity
  • Gluteus maximus muscle activity did not differ significantly between the single-leg glute-bridge (33.8% MVIC) and supine resisted hip extension (34.7% MVIC) (p=0.576).

 Hamstrings  Activity

  • Hamstrings activity was significantly less for the single-leg glute-bridge (28.4% MVIC) when compared to the supine resisted hip extension (51% MVIC) (p=0.004).

 Gluteus Maximus/Hamstrings Ratio

  • The  gluteus maximus/hamstrings ratio was significantly greater for the single-leg glute-bridge (111.4%) compared to supine resisted hip extension (59.2% MVIC) (p=0.014)
Researchers' Conclusions

The single-leg glute-bridge and supine resisted hip extension are common exercises used in rehabilitation and strengthening programs. The single-leg glute-bridge resulted in a higher gluteus maximus/hamstrings activation ratio when compared to supine resisted hip extension, primarily due to a reduction in hamstring activity. Human movement professionals may consider selecting the single-leg glute-bridge when developing corrective interventions for those presenting with relative gluteus maximus inhibition and hamstring over-activity.

How this Study Contributes to the Body of Research:

The present study investigated the activation ratio between the gluteus maximus and hamstrings during a single-leg glute-bridge (flexed knee) and supine resisted hip extension (straight-leg). Activity of the gluteus maximus and hamstrings  during a variety of exercises has been reported in dozens of studies; however, this is the only study we are aware of comparing activation ratios during the single-leg glute bride and supine resisted hip extension. This study found that gluteus maximus  activation for both exercises was similar; however, supine resisted hip extension resulted in greater hamstring activity. These findings may aid human movement professionals in optimal selection of exercise.

How the Findings Apply to Practice:

This study may aid in optimizing exercise selection based on desired muscle recruitment. For example, studies have demonstrated a relative reduction in gluteus maximus activity and increase in biceps femoris activity in those exhibiting ankle, knee, hip, sacroiliac joint and low back pain/dysfunction (1, 2). The human movement professional may consider choosing the single-leg bridge instead of the supine resisted hip extension to aid in normalizing recruitment of hip extensor musculature for individuals exhibiting signs of these dysfunctions.


  1. This study fills a gap in the literature by comparing muscle activation values for the gluteus maximus and hamstrings during the supine resisted hip extension and single-leg glute bridge exercises. Such values are already available in the literature for a range of other exercises (see Tables 1 and 2 in original article).
  2. The researchers put significant effort into standardizing the performance of exercises which may aid in reliability of EMG findings and replicability of the study, including a visual demonstration, practice trials, and a metronome to standardize the speed of exercise.
  3. The choice of two similar hip extension exercises with straight versus flexed knee, may have implications for muscle activation patterns during other lower extremity exercises.

Weaknesses and Limitations:

  1. The study did not specify whether the order of exercises was randomized, or if the amount of rest between exercises was standardized. Both of these variable may influence EMG findings of the second exercise performed.
  2. The supine resisted hip extension exercise was held for five seconds while the single-leg glute bridge was held for ten, which may bias results since average muscle activity may change over longer time intervals.
  3. Despite the expressed motivation by the authors to remediate anterior hip pain, the use of a healthy population with no identifiable Lower Extremity Dysfunction limits generalization to clinical populations.

How the Study Relates to Brookbush Institute Content?

The Brookbush Institute (BI) continues to develop and refine an evidence-based library of corrective and core exercises. This study demonstrated that a flexed-knee bridge resulted in a better gluteus maximus to hamstring activation ratio than a straight-leg bridge, when considered relative to common compensation patterns associated with dysfunction. The BI has integrated this study with others to refine recommendations for Gluteus Maximus Activation and Bridge Progressions . The BI will continue to pursue optimal practice and exercise selection by using the aggregated results of all available relevant research.

For more information check-out:

Related Videos

Gluteus Maximus Manual Muscle Testing (MMT) for an Active Population

Gluteus Maximus Isolated Activation

Ultimate Glute Bridge


  1. Brookbush, B. (2018). Lumbo Pelvic Hip Complex Dysfunction (LPHCD). BrookbushInstitute.com. https://brookbushinstitute.com/article/lumbo-pelvic-hip-complex-dysfunction-lphcd/
  2. Brookbush, B. (2017). Lower Extremity Dysfunction (LED). BrookbushInstitute.com. BrookbushInstitute.com. https://brookbushinstitute.com/article/lower-leg-dysfunction/
  3. Criswell E (2011): Introduction to Surface Electromyography, 2nd ed. Sudbury, MA: Jones and Bartlett Publishers.
  4. Ayotte NW, Stetts DM, Keenan G, Greenway EH (2007): Electromyographical analysis of selected lower extremity muscles during 5 unilateral weight-bearing exercises. J Orthop Sports Phys Ther 37: 48–55.
  5. Ekstrom RA, Donatelli RA, Carp KC (2007): Electromyographic analysis of core trunk, hip, and thigh muscles during 9 rehabilitation exercises. J Orthop Sports Phys Ther 37: 754–762.
  6. Ekstrom RA, Osborn RW, Hauer PL (2008): Surface electromyographic analysis of the low back muscles during rehabilitation exercises. J Orthop Sports Phys Ther 38: 736–745.

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