The Underlying Mechanism of Spinal Manipulative Therapy and the Effect of Pain on Physical Outcome Measures

High velocity, low amplitude spinal manipulative therapy (HVLA-SMT) will be provided to the lumbopelvic region on both sides.

A randomized crossover design is used to investigate the changes in spinal stiffness and back muscle activity of asymptomatic participants following an experimental pain induction procedure. Specifically, asymptomatic participants attend two separate sessions 5 days apart. Participants will receive 0.3 ml of 5% hypertonic saline or 0.9% isotonic saline in random order into the interspinous ligaments at L3 to L5 levels. The resulting temporal changes in pain intensity, spinal stiffness and trunk muscle activity following saline injections will be monitored. During the second session, the participants will undergo the same procedures but with the previously unused saline concentration.

No treatment