Reviewed by Tyler Tice, PT, DPT, OCS, ATC

Introduction

The gluteal muscles, particularly the gluteus medius and gluteus maximus, play a critical role in stabilizing the pelvis and controlling hip movement during functional activities. Weakness in these muscles is often linked to lower extremity pathologies such as tibial stress fractures, low back pain, iliotibial band friction syndrome, and patellofemoral pain. The study examines muscle activation during various rehabilitation exercises to determine which exercises most effectively recruit these muscles. By quantifying activation as a percentage of maximal voluntary isometric contraction (%MVIC), the study provides guidance on selecting exercises for progressive rehabilitation of the gluteal musculature. Exercises producing greater than 70%MVIC are deemed sufficient to promote strength adaptation, based on prior research.

Methods

The study involved 26 healthy subjects who participated in a single testing session. Electromyographic (EMG) electrodes were placed on the dominant gluteus medius and maximus muscles. Maximal voluntary isometric contraction (MVIC) was established through standardized manual muscle testing positions. Participants performed 18 exercises, with surface EMG data collected to assess muscle activity. Exercises were selected to include both weight-bearing and non-weight-bearing tasks, some using unstable surfaces for additional challenge. These exercises included sidelying abduction, single-limb squat, front plank with hip extension, clamshell variations, and side planks with abduction. Exercises were randomized to mitigate fatigue effects, with rest periods provided between trials. EMG data were analyzed using a root-mean-square algorithm and normalized to %MVIC.

Results

Key findings indicate that several exercises effectively activate the gluteal muscles. For the gluteus medius, the top exercises included side plank abduction with the dominant leg on the bottom (103%MVIC), side plank abduction with the dominant leg on top (89%MVIC), single-limb squat (82%MVIC), clamshell progression 4 (77%MVIC), and front plank with hip extension (75%MVIC). For the gluteus maximus, the highest activation was observed during front plank with hip extension (106%MVIC), gluteal squeeze (81%MVIC), side plank abduction with the dominant leg on top (73%MVIC), side plank abduction with the dominant leg on the bottom (71%MVIC), and single-limb squat (71%MVIC). Exercises exceeding 70%MVIC for both muscles included front plank with hip extension, side plank abduction variations, and single-limb squat. These results provide rank-ordered recommendations for gluteal strengthening, emphasizing exercises that require high levels of stability and muscle coordination.

Discussion

The findings align with prior research but offer a unique cross-comparison of gluteal muscle activation across multiple exercises. Exercises requiring stabilization, such as planks and single-limb squats, generally elicited higher activation levels. Differences in muscle recruitment between studies were attributed to variations in technique and external support. Notably, exercises like side planks with abduction and front planks with hip extension demonstrated co-contraction of core musculature, which likely enhanced gluteal recruitment. Practical applications of these findings include tailoring exercise selection to a patient’s functional capacity, with simpler tasks like clamshells used initially and more complex exercises introduced progressively.

Conclusion

This study identifies effective exercises for strengthening the gluteus medius and maximus, providing valuable insights for rehabilitation protocols. High %MVIC values observed during certain exercises support their use in targeted strengthening programs. Clinicians can use these findings to design progressive exercise programs, ensuring optimal muscle recruitment and functional outcomes.

Contributions to Physical Therapy

Gluteal muscle strengthening is essential in managing various lower extremity and low back pathologies. Exercises like front planks with hip extension and side planks with abduction not only target the gluteal muscles but also engage the core, enhancing overall stability and functional movement patterns. These exercises can be used to address muscle weakness, improve pelvic control, and reduce compensatory movement patterns. By incorporating these high-activation exercises into rehabilitation protocols, therapists can promote efficient recovery and prevent injury recurrence, ultimately enhancing patient outcomes.

1. Boren K, Conrey C, Le Coguic J, Paprocki L, Voight M, Robinson TK. ELECTROMYOGRAPHIC ANALYSIS OF GLUTEUS MEDIUS AND GLUTEUS MAXIMUS DURING REHABILITATION EXERCISES. Int J Sports Phys Ther. 2011;6(3):206-223. Accessed December 22, 2024. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3201064/

Reviewed by Tyler Tice, PT, DPT, OCS, ATC

Introduction:

Running is one of the most popular forms of physical activity. However, the popularity of running is accompanied by a high prevalence of overuse injuries. Most injuries occur in the lower extremities, with a substantial proportion affecting the foot. These injuries are often linked to biomechanical factors such as impact loading, plantar pressure, and repetitive stress, particularly on the metatarsals and soft tissues of the foot. To address these issues, research has explored biomechanical modifications, such as cadence manipulation, as a strategy to reduce injury risk. Increasing cadence has been shown to decrease step length and ground reaction forces, potentially mitigating the forces implicated in injury development. This study specifically evaluates the effects of cadence manipulation on plantar loading in healthy runners, focusing on how these changes could influence injury prevention and management.

Methods:

Thirty-eight healthy recreational runners participated in this study. Participants met inclusion criteria requiring a minimum running distance of 12.87 km per week and no musculoskeletal injuries in the prior six months. Plantar loading data were collected during treadmill running at participants’ preferred pace under three cadence conditions: preferred, 5% increased, and 5% decreased. Each trial was randomized to minimize fatigue effects, with data collected for 30 strides per condition.

Plantar loading variables analyzed included:

• Contact Time (CT): The duration of foot contact with the ground.
• Peak Force (PF): Maximum force exerted during a foot strike.
• Force Time Integral (FTI): Total force exerted over the contact period.
• Peak Pressure (PP): Maximum pressure exerted on the plantar surface.
• Pressure Time Integral (PTI): Total pressure applied over time.

These variables were measured for the total foot and four specific regions: heel, medial metatarsal, central metatarsal, and lateral metatarsal.

Results:

The study found that cadence manipulation significantly influenced plantar loading patterns:

1. Increased Cadence (+5%):
   • Decreased CT, PF, and PTI for the total foot and all foot regions.
   • Reduced heel loading, including lower pressure and force variables.
   • Lower metatarsal loading across medial, central, and lateral regions.
2. Decreased Cadence (-5%):
   • Increased CT and higher PF and PTI values in the heel and metatarsal regions.
   • Elevated total foot loading, with more pronounced force and pressure variables.

Discussion:

The results underscore the biomechanical benefits of increasing cadence during running. A faster cadence reduces plantar loading by decreasing contact time and ground reaction forces. Notably, this study refuted the hypothesis that increased cadence would elevate metatarsal loads; instead, all regions of the foot experienced reduced loading. These effects may be attributed to reduced vertical oscillation of the body’s center of mass and a decreased foot inclination angle at initial contact.

From a clinical perspective, cadence manipulation presents a promising strategy for reducing the risk of overuse injuries, such as plantar fasciitis, Achilles tendinopathy, and metatarsal stress fractures. By lowering repetitive loads on vulnerable foot structures, a 5% increase in cadence can mitigate the cumulative stress associated with long-distance running.

Conclusion:

This study highlights the potential of cadence manipulation as an effective tool for injury prevention and rehabilitation in runners. A modest 5% increase in cadence reduces plantar loading across all foot regions, suggesting that cadence training could be integrated into physical therapy protocols for managing running-related injuries. Given the small but meaningful biomechanical changes observed, cadence adjustments should be considered alongside other therapeutic interventions, such as strength training and gait retraining, to optimize treatment outcomes.

Implications for Physical Therapy:

The findings of this study have direct applications in physical therapy practice. For patients recovering from lower extremity injuries or seeking to prevent future injuries, cadence training offers an evidence-based intervention to reduce plantar stress and improve running mechanics. Physical therapists can use tools like metronomes or wearable devices to guide patients in cadence adjustments, ensuring gradual and sustainable changes in running form. Furthermore, cadence manipulation can complement traditional rehabilitation approaches, such as strengthening exercises for the intrinsic foot muscles and addressing biomechanical deficits in the kinetic chain. By incorporating cadence training into a comprehensive rehabilitation program, therapists can enhance patient outcomes, reduce injury recurrence, and promote safe, efficient running mechanics. This approach aligns with the growing emphasis on personalized and biomechanically informed physical therapy interventions.

1. Wellenkotter J, Kernozek T, Meardon S, Suchomel T. The Effects of Running Cadence Manipulation on Plantar Loading in Healthy Runners. International journal of sports medicine. 2014;35. doi:10.1055/s-0033-1363236

Reviewed by Tyler Tice, PT, DPT, OCS, ATC

Article:

Patellofemoral Pain Clinical Practice Guidelines Linked to the International Classification of Functioning, Disability and Health From the Academy of Orthopaedic Physical Therapy of the American Physical Therapy Association

Introduction:

The orthopaedic section of the American Physical Therapy Association (APTA) published these clinical practice guidelines in 2019 to give recommendations to clinicians in the differential diagnosis, assessment and treatment of patellofemoral pain.

These recommendations are designed to fit into the International Classification of Functioning, Disability, and Health (ICF model) that was introduced by the World Health Organization (WHO) to improve clinician’s ability to appropriately treat and communicate with patients by including pathoanatomical, psychosocial and societal factors when assessing a patient’s wants and needs.

Methods: 

Content experts were appointed by the orthopedic section of the APTA to search the current literature for articles relating to the treatment, assessment and diagnosis of patellofemoral pain.  Articles included were taken from MEDLINE, Scopus, CINHAL, SPORTDiscus, and the Cochrane Library with dates ranging from 1960 to 2018.

The chosen articles were then categorized based on level of evidence where I represented the highest quality evidence and V represented expert opinion.  After the evidence was reviewed and ranked, the experts developed and ranked recommendations utilizing the information.  A ranked recommendations were based on strong evidence while F ranked recommendations were based on expert opinion.  These recommendations were further categorized into the following content areas; diagnosis, classification, examination, and interventions.

Results: 

After reviewing the available literature, the authors made the following recommendations:

Clinicians should use the reproduction of pain behind or around the patella during squatting or other motions that load the patellofemoral joint in a flexed position to help diagnose patellofemoral pain.

The following factors can be used to diagnose patellofemoral pain:  pain behind or around the patella, reproduction of pain when the patellofemoral joint is loaded in a flexed position, exclusion of all other conditions that can cause anterior knee pain including tibiofemoral pathologies.

Clinicians can use the patellar tilt test with the presence of hypomobility to support the diagnosis of patellofemoral pain.

Since there are no previously established classifications of patellofemoral pain, the authors propose the following 4 classifications:  overuse/overload without other impairments, muscle performance deficits, movement coordination deficits, and mobility impairments.

Clinicians should use the following patient reported outcome measures when assessing patients with suspected patellofemoral pain:  the Anterior Knee Pain Scale, the patellofemoral pain and osteoarthritis sub-scale of the Knee Injury and Osteoarthritis Outcome Score, the Visual Analog Scale, the Eng and Pierrynowski Questionnaire, the Numeric Pain Rating Scale.

Clinicians should use functional tests such as squats, or step downs that reproduce patellofemoral pain to assess a patient’s progress throughout an episode of care.

Clinicians may use body structure and function impairments such as joint hypomobility, muscle weakness and lack of muscle extensibility to assess progress throughout an episode of care.

Clinicians should employ an exercise approach that targets both hip and knee musculature.  During the early stages of therapy, exercises targeting the posterolateral hip musculature is preferred but as the plan of care continues, targeting knee musculature as well is essential.

Clinicians may use patellar taping in the early stages of rehabilitation with the goal of reducing pain to enhance exercise performance.  Evidence shows that this can be helpful early on but generally has no lasting impact on prognosis or symptoms.  Clinicians should not prescribe knee orthoses such as knee sleeves or braces for the treatment of patellofemoral pain.

Clinicians may prescribe prefabricated foot orthoses for patients with greater than normal foot pronation during the early stages of rehabilitation in concert with an exercise program.  There is limited evidence suggesting that custom foot orthoses are more effective than prefabricated foot orthoses.

Clinicians should not use electromyography-based biofeedback on medial vastii activity to augment quadriceps exercise therapy for the treatment of patellofemoral pain.  Clinicians should also not use visual biofeedback on lower extremity alignment during hip and knee targeted exercise during the treatment of patients with patellofemoral pain.

Clinicians may use gait retraining during running for multiple sessions to adopt gait changes during running for patients with patellofemoral pain.

Clinicians may use blood flow restriction plus high-repetition knee exercises for those with limited or painful resisted knee extension.

Clinicians should not use dry needling for the treatment of patellofemoral pain, however acupuncture may be used to reduce pain.  There is limited evidence that acupuncture is more effective than placebo so caution should be exercised with this recommendation.

Clinicians should not use joint mobilizations or manipulations as a stand-alone treatment for patellofemoral pain.  Clinicians should not use biophysical agents including ultrasound, cryotherapy, phonophoresis, iontophoresis, electrical stimulation, or therapeutic laser therapy to treat patellofemoral pain.

Evidence suggests that patient education regarding plan of care, patellofemoral joint loading and Kinesio phobia helps to improve exercise program compliance to a rehabilitation exercise program.  The evidence suggests that a multimodal approach is ideal in the treatment of patellofemoral pain but that exercise is the primary factor in successful treatment.

Discussion and clinical utility:

This CPG is helpful because it provides new classifications of patellofemoral pain to help clinicians guide their plans of care.  It is also useful to see that exercise is the biggest factor in the effective treatment of patellofemoral pain.  This helps clinicians empower patients to be active and help treat their own symptoms.

References:

Willy RW, Hoglund LT, Barton CJ, Bolgla LA, Scalzitti DA, Logerstedt DS, Lynch AD, Snyder-Mackler L, McDonough CM. Patellofemoral Pain. J Orthop Sports Phys Ther. 2019 Sep;49(9):CPG1-CPG95. doi: 10.2519/jospt.2019.0302. PMID: 31475628.