THE ACUTE EFFECTS OF COMMON PHYSICAL THERAPY INTERVENTIONS ON PASSIVE HAMSTRING STIFFNESS: A BLINDED RANDOMIZED CONTROLLED TRIAL

Abstract

Purpose/Hypothesis : The purpose of this study was to compare the effects of common physical therapy techniques on acute hamstring muscle passive stiffness. The hypothesis is that dry needling, stretching, and foam rolling will improve hamstring passive stiffness, and that eccentric exercise may have the reverse effect of increasing passive muscle stiffness.Number of Subjects : 100 subjects.Materials/Methods : Subjects who met inclusion criteria had their initial passive hamstring length of the right leg measured using the “90-90 test” and a bubble inclinometer by a researcher blinded to the treatment. The measurement was taken when the subject perceived a “strong but tolerable stretch”. They were randomized to one of 5 groups, dry needling (DN), foam rolling, stretching, eccentric exercise, or control. The DN group received pistoning technique to 3 to 5 trigger points. The foam roller group performed self-guided myofascial release using a 6 inch diameter foam roller in a long sitting position with knees extended and feet relaxed. . Subjects rolled for 30 seconds with 30 seconds rest for 3 sets. The stretching group preformed an active self-stretch in supine held for 30 seconds with 30 seconds rest for 3 sets. The exercise group performed an eccentric hamstring exercise commonly known as the Nordic exercise for 10 repetitions with 30 seconds rest for 3 sets. At completion of treatment the subject had their hamstring range