The effects of therapeutic hip exercise with abdominal core activation on recruitment of the hip muscles.
Level 4 - case-series / case-control
Single-session laboratory crossover EMG study in healthy subjects evaluating acute biomechanical surrogate outcomes.
PubMed 28732494 · doi:10.1186/s12891-017-1674-2
What was done
Surface electromyography (EMG) of bilateral internal obliques (IO), upper gluteus maximus (UGMax), lower gluteus maximus (LGMax), gluteus medius (GMed), and biceps femoris (BF) was measured in 20 young, healthy participants. Subjects performed three therapeutic hip exercises (clam, side-lying hip abduction [HABD], and prone hip extension [PHE]) under two conditions: natural core activation (NC) and enhanced core activation (CO, verified as >20% maximal voluntary isometric contraction [%MVIC] of the IO). Muscle contractile properties were assessed using tensiomyography (TMG).
What was found
Enhanced core activation significantly increased EMG activation (%MVIC) for GMed in all phases of the clam exercise (P < 0.05), UGMax across all phases of PHE (P < 0.05), LGMax during the eccentric phases of all three exercises (P < 0.05), and BF across all phases except the eccentric phase of PHE (P < 0.05). Across both conditions, UGMax activation was significantly greater than LGMax in all phases of clam and HABD (P < 0.001), whereas LGMax was higher than UGMax during the concentric phase of PHE under NC (P = 0.003). Gender, physical activity level, and TMG parameters were not major covariates.
Why it matters
Actively bracing the abdominal core during common hip rehabilitation exercises increases recruitment of specific gluteal muscle subdivisions and the hamstrings, supporting the biomechanical rationale for combining core stabilization with hip strengthening.
Limits
The study included only a small cohort (n = 20) of young, asymptomatic individuals, limiting direct applicability to clinical populations with lower-limb pathology. It assessed acute surface EMG amplitudes rather than longitudinal strength gains, injury recovery, or long-term clinical outcomes.
Cited by
- supports Lateral hip abduction exercises target and develop the gluteus medius, gluteus minimus, and the upper subdivision of the gluteus maximus.