The hip flexors, particularly the iliopsoas muscle, play a crucial role in stabilising the front of the hip and helping you lift your leg when walking, running, or climbing stairs. When these muscles are weak, tight, or poorly controlled, it can lead to hip or groin pain, instability, and even lower-back issues.
What the Study Looked At
This 2024 systematic review (Juan et al., Journal of Clinical Medicine) analysed nine studies examining hip-flexor activation during common rehabilitation and gym exercises. Using electromyography (EMG) – a tool that measures how much a muscle “fires” – the researchers identified which movements most effectively target the iliopsoas.
Key Findings
● Greatest activation occurred between 30° and 60° of hip flexion, especially during active straight-leg raises and supine leg lifts.
● Leg-lowering and raising exercises produced over 60 % muscle activation, showing they are excellent for strengthening the iliopsoas.
● Exercises where the leg moves on a stable trunk created more activation than those where the trunk moves on the leg (for example, sit-ups).
● Adding resistance or external load further increased muscle activity.
● The researchers proposed a progressive approach, starting with gentle, supported movements, then advancing to open-chain leg lifts and resisted hip-flexion work.
What This Means for You
● Strong hip flexors help improve posture, running efficiency, and hip stability, particularly if you experience hip discomfort or feelings of “instability”.
● If you have hip dysplasia, micro-instability, or anterior hip pain, targeted iliopsoas strengthening can reduce strain on other hip structures such as the labrum.
● These exercises can also aid recovery after hip replacement and improve balance and speed in sports like football and sprinting.
Takeaway
Building hip-flexor strength is about quality, not quantity. Controlled, progressive exercises in mid-range hip flexion offer the best way to restore power and stability to the front of the hip. Whether you’re an athlete, recovering from surgery, or managing chronic hip tightness, adding specific hip-flexor work can help you move more confidently and comfortably.
Research Blog By: Emre Oz (Musculoskeletal Physiotherapist at Crouch Physio).
Reference:
Juan, J., Leff, G., Kevorken, K., & Jeanfavre, M. (2024). Hip Flexor Muscle Activation During Common Rehabilitation and Strength Exercises. Journal of Clinical Medicine, 13(6617).
