This video covers Supine Sleeper Hip Internal Rotation (IR) PAILs/RAILs - a drill designed to expand and strengthen hip IR so the range you gain is range you can actually control. Hip internal rotation is a major piece of healthy hip mechanics for squatting, running gait, cutting/pivoting, and long-term hip and knee resilience. When IR is limited, the body often steals motion from the pelvis, low back, or feet, which can show up as cranky hips, irritated knees, or “stuck” squat positions over time.

A key point in this drill: the goal is not to force the knee to the floor. The goal is clean hip IR with minimal compensation from the pelvis and spine. As your true hip IR improves, the knee will naturally get closer to the ground over time. Chasing the floor usually just teaches you to twist through the pelvis instead of rotating the hip.

The sequence (repeatable for sets or reps):
1. Passive stretch (~2 minutes): settle into the supine sleeper IR position and breathe, allowing the tissues to adapt while you refine alignment.
2. PAILs (progressive isometric contraction): gradually ramp tension pushing out of the stretch to create the intended stimulus for the day.
3. RAILs (regressive isometric contraction): reverse the intent and actively pull deeper into the newly available IR range with controlled effort.
4. Sink into the new range: ease off slightly and settle into the position you just earned.
5. Repeat for additional rounds if you’re doing multiple sets.

Programming note: The iso duration, intensity, and total time under tension depend on the goal of the day - lighter/shorter for prep and patterning, heavier/longer for strength and adaptation.