PIR / PFS for the Hamstrings

How to do it

1. Supine, raise the straight leg to the hamstring barrier (first palpable resistance).
2. Barely contract the hamstrings (press the heel down toward the table) for 20 to 30 s (PIR) or 8 to 10 s maximal (PFS).
3. Relax completely; allow the leg to move further into hip flexion through relaxation.
4. For PFS, the clinician rapidly moves the leg into the new stretch range and holds ~15 s, then rests ~20 s.
5. Repeat 3 to 4 times into progressively greater range.

Form cues

• Keep the knee straight and the opposite leg down.
• Shortened hamstrings contribute to the posterior pelvic tilt / sway-back posture; restore length to allow neutral pelvis.
• Relax fully between repetitions; gains taper after ~4 cycles.

Dosage

PIR: 20-30 s hold x3-4. PFS: 8-10 s contraction, 15 s stretch, 20 s rest x4.

Muscles worked

Stretches: hamstrings

Target muscles

Related exercises