Effects of an Acute Mindfulness-based Intervention on Exercise Tolerance, Maximal Strength, Pain and Effort-Related Experiences in Individuals with Primary Chronic Low Back Pain: a Pilot Study

Introduction: This study investigated the effects of an acute mindfulness-based intervention on exercise tolerance, maximal voluntary contraction (MVC), pain and effort-related experiences in individuals with primary chronic low back pain. Method: Participants were randomly assigned to an experimental group and a control group. Before and after the intervention, participants completed a MVC test, a modified Sorensen test and numerical rating scales about pain intensity, pain unpleasantness, perceived effort and use of coping strategies. Dispositional measures such as pain catastrophizing, trait anxiety, dispositional mindfulness and impulsivity were also assessed. T -tests and linear mixed models were performed. Results: Participants from the control group significantly decreased their MVC across time and showed a trend towards a decrease in exercise tolerance over time, which was not the case for the experimental group. For both groups, pain unpleasantness and effort were perceived higher during the second modified Sorensen test. Analyses revealed neither significant effect of time nor group on pain intensity and the use of coping strategies. Discussion: The results highlight the value of involving individuals with primary chronic pain in mindfulness-based interventions to improve adaptations to effort while targeting referred pain. Larger samples and controlling for individuals’ functional status appear necessary for further research.