## 4 Discussion  
The objective of the present study was to evaluate the therapeutic efficacy of an acquressure mat (Mysa(r)) associated with a specific rehabilitation program in patients with nonspecific chronic low back pain. Our results suggest that the rehabilitative protocol proposed to all the participants gave a significant positive effect in terms of reducing pain and disability, especially immediately after the end of the supervised sessions, while a significant improvement in life quality was found only in the experimental group. Based on the most recent recommendations, the rehabilitative approach we proposed also included patient education about the pathogenesis of pain and about the rules of postural and behavioral hygiene. Indeed, as stated by different international guidelines, individuals with chronic LBP usually need to be provided with advice and education about the nature of low back pain to minimize disability and promote participation in physical and social activities [28; 29]. Education is an easily available and inexpensive treatment option that explains to subjects how to protect their back in activities of daily living based on anatomical, physiological and ergonomic principles (the biomedical model). It also involves pain biology education, or \"explaining pain\", that aims to reconsider pain as a protective output of the brain rather than a simple sign of tissue damage [30; 31]. According to current evidence-based clinical guidelines, exercise therapy (of any type) is one of the few recommended treatments for chronic LBP and typically includes a graded activity or exercise program that targets improvements in function and prevention of worsening disability [10]. Indeed, many studies showed that exercise training is effective in reducing pain when compared to that of non-exercise, training-based treatments in adults [32]. Since there is no evidence showing that one form of exercise is better than another, guidelines typically recommend exercise programs that take individual needs and characteristics, preferences, and capabilities into account in deciding what type of exercise [7; 33]. However, some works support the efficacy of resistance and stabilization/motor control exercise training and state that stretching exercises are most associated with pain reduction, while strengthening yields greatest functional gains [34]. In a recent review of [PERSON] et al., exercise training was demonstrated to be more effective than hands-on therapist treatments [35]. The exercise protocol proposed in this work was directed by an expert physiotherapist. Basing on the previous literature, patients firstly underwent a clinical assessment to de  
Figure 6: Median scores of EuroQol-5D over time in two treatment groups. termine eventual signs of segmental hypo mobility or hypermobility and the progression of the exercises was directed accordingly [36]. In addition to spine mobilization exercises, the therapeutic program included muscle strengthening and stretching, motor control, and breathing exercises; they consisted of mainly open chain ground exercises, and some of them included the use of a fit ball. As [PERSON] and [PERSON] demonstrated that an alteration in the timing of core muscle activation in subjects with LBP, particular attention was placed on core stability exercises [37]. Considering the chronicity of pain and disability, the therapeutic intervention also involved the education of the patients to repeat the exercises learned in a home setting, with the aim of improving and maintaining over time the effects of the supervised rehabilitative program. The patients were provided illustrated brochures describing the exercises, their purpose and how to incorporate them into their activities of daily living. Moreover, an important factor that influences the individual success of exercise rehabilitation is represented by the patient's adherence to the proposed treatment. In a prospective study, [PERSON] et al.