Multimodal intervention based on physical exercise, mindfulness, behaviour change and education to improve pain and health in patients with chronic primary low back pain: a study protocol of the HEALTHYBACK randomised controlled trial.

The HEALTHYBACK trial is based on a multimodal intervention to determine the effectiveness of a supervised physical exercise, mindfulness, behaviour change and pain neuroscience education programme on several health variables in individuals with chronic primary low back pain (CPLBP). The study will be a randomised controlled trial among 70 individuals diagnosed with CPLBP (aged 18-65 years). The intervention will be conducted in person within a hospital setting for 16 weeks and comprises a first phase (16 sessions supervised physical exercise (2 days/week, 45 min/session), mindfulness (1 day/week, 2.