Hip Adductor Muscle Forces during Strength Training and Rehabilitation Exercises.
Level 4 - case-series / case-control
Cross-sectional laboratory study using biomechanical modeling without clinical endpoints (level by design analogy).
PubMed 41931009 · doi:10.1249/MSS.0000000000004002
What was done
Fifteen injury-free participants performed eight exercises: squat, deadlift, sumo deadlift, step up, lateral slide, lying leg lift, and Copenhagen adduction (short and long lever). Researchers measured 3D kinematics, ground reaction forces, and surface electromyography to drive an EMG-assisted neuromusculoskeletal model that estimated individual muscle forces for the adductor brevis, adductor longus, adductor magnus (pubofemoral and ischiocondylar portions), and gracilis. Exercises were classified into three tiers using k-means clustering based on peak normalized muscle forces.
What was found
The abstract reports exercise tier rankings without absolute numerical force values. The Copenhagen long lever exercise was ranked tier 1 for all adductor muscles. The Copenhagen short lever was tier 1 for adductor brevis and longus. Deadlift and sumo deadlift were tier 1 for adductor magnus (ischiocondylar) and gracilis. Squat and step up were tier 1 for adductor magnus (ischiocondylar). Lateral slide was tier 2 across all muscles. Lying leg lift was tier 2 for adductor brevis and longus and tier 3 for adductor magnus and gracilis. Squat was tier 2 for adductor longus, adductor magnus (pubofemoral), and gracilis. Step up was tier 2 for gracilis and tier 3 for adductor brevis, longus, and magnus (pubofemoral).
Why it matters
This ranking clarifies which specific strength and rehab exercises impose high peak loads on distinct hip adductor compartments, showing that Copenhagen exercises target adductors globally while compound hip extension exercises specifically stress the ischiocondylar portion of adductor magnus.
Limits
The sample was small (n = 15) and restricted to uninjured participants. Muscle forces were derived from computational musculoskeletal modeling rather than direct in vivo tension measurements, and the study did not measure long-term training adaptations, injury prevention efficacy, or clinical rehabilitation outcomes.
Cited by
- supports Vertical hip extension exercises, such as squats and lunges, significantly recruit and load the inner thigh adductor muscles.