Thirty patients with chronic unspecific low back pain were randomised in a crossover design to receive a 10-minute isometric core-stabilisation session (forearm/side planks, static swimmers, supine bridge; n=30) or a 10-minute seated rest control (n=30). The primary outcome of interest was change in local lumbar pressure pain thresholds (PPT_local). Secondary outcomes of interest included remote PPT (forehead, thenar), local vs remote ΔPPT interaction, and correlations of ΔPPT with pain catastrophizing, kinesiophobia, physical activity, current/chronic pain intensity, BMI, and perceived exertion. Outcomes were assessed immediately post-intervention (~60 s). Overall, the results of the study revealed a significant Time×Intervention interaction for PPT_local, with higher post-exercise thresholds after core training but not after control; no exercise effect emerged at remote sites, and greater catastrophizing was moderately associated with smaller local EIH. In short, a simple 10-minute core routine elicited immediate, local hypoalgesia without systemic spread, and catastrophizing dampened the response.