Dor lombar crônica e exercício físico: da avaliação ao treinamento

Abstract

Non-specific chronic low back pain (NSCLBP) is the leading cause of disability worldwide, particularly among women aged 40 to 80 years. Despite its high prevalence, there is a lack of understanding regarding best practices for prevention and treatment. Physical exercise is the primary recommended intervention, with functional training (FT) and dual- task training (DTT) both showing effectiveness in pain reduction, although no consensus exists on which modality is superior. This thesis aimed to evaluate the effects of different physical training approaches on low back pain outcomes. Study 1 investigated accessible methods for pain assessment, presenting quantitative sensory testing and simple questionnaires for a multidimensional approach. Study 2 reviewed the mechanisms of action of Functional Training (FT) and Dual-Task Training (DTT) in low back pain, suggesting that FT improves trunk stability and functional capacity, while DTT appears to inhibit pain-related circuits and activate brain regions associated with analgesia. In Study 3, thirty-eight women aged 60–79 years with NSCLBP were randomly assigned to FT or DTT groups and participated in 16 weeks of training. FT consisted of circuit exercises simulating daily activities, while DTT involved the simultaneous execution of motor and cognitive tasks. We assessed pressure pain threshold (PPT), temporal summation (TS), conditioned pain modulation (CPM), trunk instability, isometric strength, and trunk muscle endurance. In Study 4, seventy volunteers with and without NSCLBP were divided into four groups (FT with NSCLBP, FT without NSCLBP, DTT with NSCLBP, and DTT without NSCLBP) and followed the same training protocol as in Study 3. In addition to the previously mentioned variables, we also evaluated functional fitness. In Study 3, FT resulted in greater improvements than DTT in PPT and CPM (p < 0.05), with no effect on TS. Both interventions increased maximum isometric strength of trunk extensors (p < 0.001), with no between-group differences. Endurance of trunk extensors (p = 0.01) and lateral flexors (p < 0.001) increased only in the DTT group, without significant group differences. No changes were observed in trunk stability or endurance of trunk flexors. In Study 4, both training modalities improved trunk stability (p < 0.05) and isometric strength of flexors and extensors (p < 0.001), with no differences between groups. Women with NSCLBP showed greater flexor strength than those without pain (p = 0.03), while women without NSCLBP showed greater extensor strength (p = 0.02). Endurance of trunk flexors and extensors improved in both groups (p < 0.05). Lateral flexor endurance increased significantly only in the DTT group, especially among women with NSCLBP (p < 0.05). Functional fitness improved in all groups (p < 0.05), regardless of pain status. We conclude that there are practical and low-cost methods for pain assessment, that the analgesic mechanisms differ between the investigated training modalities, and that both FT and DTT are effective for managing NSCLBP in older women.