Develop active hip flexor strength in external rotation with this 90/90 ER flexion lift-off drill — a precise, demanding movement that isolates the hip flexors in one of their most challenging positions and builds the kind of active control that passive stretching simply cannot develop.

Seated in the 90/90 position, the focus is entirely on the front leg in external rotation. The task is to contract the hip flexor tissue — the regressive, short-side muscles at the front of the hip — to lift the knee and ankle off the floor simultaneously, bringing the leg into flexion without any rocking, shifting, or use of momentum. The movement must come entirely from tissue engagement — pure muscular effort, nothing borrowed from the torso or pelvis.
The angle of the front leg is your built-in load management tool. A smaller, more closed angle between the shin and the body shortens the hip flexors further, making the lift significantly harder. A more open angle lengthens the position slightly, reducing the demand and making the lift more accessible. Adjust the angle to find the threshold where a clean, uncompensated lift is possible — then work to close that angle over time.

Lifting the knee and ankle off the floor in this position requires the hip flexors to generate force while the hip is already in external rotation — a combined demand that most people have never trained directly. The external rotation component challenges the hip flexors to work outside their most familiar plane of motion, exposing weaknesses in rotational hip control. The strict no-rocking, no-momentum rule ensures every rep is honest and every contraction is real. This is end range strength training for the front of the hip — building the active capacity that supports better movement, reduced hip flexor tightness, and improved performance in any activity that demands hip flexion control.

Expect a sharp, concentrated effort deep at the front of the hip — the hip flexors working hard to initiate and sustain the lift without any help from the rest of the body. The lift may be small and the hold brief — that is completely correct. What matters is that the contraction is pure, the position is honest, and no momentum or compensation is used to get the leg off the floor. Over time, this builds the active hip flexor strength in ER that translates to better athletic performance, smoother gait, and long-term hip health.