Reflex effects of a spinal adjustment on autonomic nervous system function

The purpose of this study is to investigate the effect a spinal adjustment on the autonomic nervous system (ANS). A spinal adjustment is the term chiropractors use for spinal manipulation. This study will investigate whether a single spinal adjustment results in short term changes to the ANS. Measures of ANS activity will include blood pressure, heart rate variability and other non-invasive modalities associated with autonomic function. This study will be conducted as a randomised controlled trial. Each trial will take place during a routine chiropractic visit at the New Zealand College of Chiropractic (NZCC) student health centre.The first trial we aim to conduct will involve monitoring blood pressure. During each trial participants will have their blood pressure taken and then have their spine checked by an experienced chiropractor. If assigned to the experimental group they will receive a spinal adjustment based on their palpation findings, the control group will be set up for an adjustment but no manipulation will take place. The groups will then have their blood pressure monitored immediately post intervention. Following this the participant will receive any further spinal adjustments deemed necessary based on their chiropractic analysis. Volunteers will be sought from active patients currently presenting to the NZCC student health centre. Research Question: Does a spinal adjustment result in a short-term change in autonomic nervous system (ANS) activity? If so, does the nature of this change depend on the region of the spine adjusted? Null hypothesis: That a spinal adjustment will cause no short-term change in ANS activity. Hypothesis 1: That a spinal adjustment will cause a short term change in ANS activity. Hypothesis 2: That the nature of the change in ANS activity following a spinal adjustment will be dependent on the region of the adjusted.