The aim of the proposed study is to add to the literature pertaining to the effects of spinal manipulation on PPT. To date, no studies have assessed whether or not there is an additive effect of multiple manipulations during a single treatment session on PPT. The proposed study will assess potential changes in PPT between baseline measurements, following a single cervical or lumbar manipulation, and after the delivery of second spinal manipulation performed on a different segment. The study design will allow for the investigation of possible additive effects, as well as for the effect of the first manipulation to be assessed independently of the second. Order of delivery of the cervical and lumbar manipulation will be randomized among participants to allow investigators to consider the possibility that the order of the manipulations impacts PPT changes.