The effects of lumbar spinal manipulation on athletes’ symmetry: a prospective randomized study*

Abstract

Objectives: the purpose of this prospective study among healthy athletes was to verify the possible effects of lumbar manipulation on symmetry, analysing the measured outcomes from physical tests. Methods: Young athletes of both genders were selected according to the eligibility criteria, randomly allocated into experimental and control groups. Data were collected with two force platforms integrated with motion capture system, to retrieve the bilateral ground reaction forces, to apply the symmetry index. All participants performed three commonly used physical performance tests, including static posture, squat, and vertical jump, before and after the lumbar manipulation and control intervention. Results: In the group 1 pre- to post-lumbar manipulation, statistically significant differences were found in bilateral symmetry. The improvement of symmetry was found in static post-lumbar spinal manipulation. In the group 2 pre- to post-control intervention, no statistically significant differences were found. Conclusions: The athletes from group 1, benefited regarding to the static symmetry after lumbar intervention. These findings suggest that one single lumbar spinal manipulation, actually took place, producing effects on symmetry.