While strengthening the hip flexors in order to get higher legs is important, there are several different hip flexors which need to be trained very specifically to support the leg en l’air. Understanding the anatomy of this area is crucial to chosing the correct strenthinening exercises, and avoiding overloading muscles that are already struggling.
Resistance training often overloads the superficial hip flexors (TFL and Rectus Femoris) rather than strengthening the deeper layers of Iliacus and Psoas Major. Repeated overuse of the hip flexors under load, without the appropriate patterning, often results in inflammation of the front of the hips, and this is especially common in young dancers.In addition, deep back control and dynamic core stability is an essential element in getting the Psoas Major to actually function as a hip flexor, so retraining for increased height of legs needs to start with some very specific deep core control exercises, rather than loading the legs.
The following video explains the anatomy of the hip in relation to getting your leg higher in a développé devant.