Differences in the Electromyographic Activity of Lower-Body Muscles in Hip Thrust Variations.
Level 4 - case-series / case-control
Cross-sectional repeated-measures laboratory biomechanics study (graded by design analogy)
PubMed 30335717 · doi:10.1519/JSC.0000000000002859
What was done
Seven experienced personal trainers performed 4 variations of the barbell hip thrust using a load of 40% of their one-repetition maximum (8 repetitions per variation, with 3 minutes of rest between sets). Variations modified foot distance from the body and the intentional direction of applied force (hip external rotation and knee flexion). Surface electromyography (EMG) was measured in the rectus femoris, vastus medialis, vastus lateralis, gluteus maximus, gluteus medius, biceps femoris, and semitendinosus.
What was found
Repeated-measures ANOVA showed statistically significant differences in EMG activity across variations for all evaluated muscles except the gluteus medius. The abstract provides no specific numerical values, percentages, or effect sizes.
Why it matters
Modifying foot placement and cueing directional force during hip thrusts alters recruitment patterns in the quadriceps, hamstrings, and gluteus maximus, which may help coaches tailor the movement to specific target muscles.
Limits
The sample size was extremely small (n = 7) and restricted to experienced personal trainers, limiting generalizability. The abstract reports no numerical data or effect sizes, and acute surface EMG activation does not directly measure long-term hypertrophy or strength outcomes.
Cited by
- supports During a hip thrust, placing the feet too close shifts the sensation to a stretch in the rectus femoris rather than glute activation.
- supports During a hip thrust, placing the feet too far forward shifts the focus and sensation more toward the hamstrings.