Immediate Comparative Effect of Post-Isometric Relaxation and Reciprocal Inhibition Techniques on Hamstring Flexibility in Patients with Hamstring Tightness

Abstract

Background: Hamstring are essential for posture stabilization, pelvis control activities like walking and running .Tight hamstrings can lead to functional impairments, postural issues and low back pain. Muscle energy techniques (MET) using controlled isometric or isotonic contractions are effective in reducing muscle tightness ,improving flexibility and enhancing range of motion .These techniques leverage post isometric relaxation (PIR) and reciprocal inhibition (RI) to promote muscle relaxation. Objective: This study aims to investigate the effect of post isometric relaxation and reciprocal inhibition techniques on hamstring flexibility. Methods: This will be quasi experimental control trial in which convenient sampling will be done from Government institutes of Faisalabad after meeting inclusion and exclusion criteria. Forty individuals with hamstring tightness will be assigned into two groups: Group A and Group B. Group A will receive post isometric relaxation technique (one session 3 repititions) and group B will receive reciprocal inhibition technique (one session 3 repititions). Results:Post isometric relaxation showed significant pain reduction (Z = -3.694, p < .001, d = 2.82) and strong improvements in knee extension (d = -1.75) and hamstring flexibility (d = 1.63). Reciprocal inhibition also led to notable pain relief (Z = -2.645, p = .008, d = 2.17) with moderate gains in flexibility and knee extension. Conclusion:Both PIR and RI effectively reduced pain and improved flexibility, with PIR showing superior short-term benefits in enhancing function among females with hamstring tightness.

Keywords: Post- sometric relaxation, Reciprocal inhibition, immediate effect