Equilíbrio e controle motor em mulheres com fibromialgia: uma análise quantitativa e qualitativa dos aspectos somatossensoriais, autonômicos, funcionais e perceptivos.

Abstract

Fibromyalgia is a chronic pain syndrome characterized by multisystem manifestations that affect motor control, functional performance, and the way individuals perceive, interpret, and attribute meaning to their own movements in daily life. Although functional alterations are frequently described, studies integrating objective measures of physical performance, such as balance, with the perceptions of movement reported by women with fibromyalgia remain limited. Understanding this relationship may contribute to a more integrated interpretation of the functional limitations associated with fibromyalgia, expanding the possibilities for movement-focused clinical assessment and intervention. Therefore, the aim of this study was to investigate dynamic balance in women with fibromyalgia by comparing their performance with that of healthy women and analyzing its associations with pain, fatigue, muscle strength, physical fitness, central adiposity, and autonomic modulation, as well as to understand, from a qualitative approach, how these alterations are perceived and experienced in daily life. Methods: This study comprised two phases, one quantitative and the other qualitative. The quantitative phase, a comparative cross-sectional design, involved 32 women with fibromyalgia and 32 matched healthy women. Dynamic balance was assessed using the Y-Balance Test (YBT) and analyzed in conjunction with measures of pain (11-point numerical scale, temporal summation, conditioned pain modulation, and pressure pain threshold), fatigue (Multidimensional Fatigue Inventory), physical fitness (6-minute walk test), isokinetic muscle strength, central adiposity (waist-to-height ratio), and cardiac autonomic control (heart rate variability). Quantitative analyses included comparisons between groups and tests of association between balance performance and clinical and functional variables. For the qualitative phase, another 30 women participated in semi- structured interviews, which were analyzed using phenomenological analysis based on Bardin's content analysis, guided by the frameworks of motor control and the lived body. Results: In the quantitative comparison between groups, women with fibromyalgia showed significantly poorer performance in dynamic balance compared to healthy women, evidenced by lower functional reach in the YBT (p < 0.05). Within the fibromyalgia group, balance performance showed significant associations with greater pain intensity, higher fatigue, lower physical fitness, and reduced muscle strength. Qualitative analysis revealed that balance is experienced as an expression of a body marked by constant vigilance and the need for movement monitoring, insecurity, and a continuous need for adaptation. Participants reported difficulties in movement automaticity, reduced confidence in moving, reorganization of daily tasks, and a direct impact on social participation. Conclusion: The impairment of dynamic balance in women with fibromyalgia suggests alterations in motor control that involve both measurable functional changes and transformations in the perception and meaning of movement. The integration of quantitative and qualitative findings indicates that balance acts as a functional marker associated with the interaction between pain, fatigue, physical performance, and bodily experience, reinforcing the need for therapeutic approaches that consider movement in an integrated manner, encompassing biomechanical, autonomic, perceptual, and psychosocial aspects.