Relationship between core function and pressure pain threshold in senior women with non-specific chronic low back pain: cross-sectional study / Relação entre a função do core e o limiar de dor a pressão em mulheres idosas com dor lombar crônica inespecífica: estudo transversal

ABSTRACT BACKGROUND AND OBJECTIVES: Chronic nonspecific low back pain (CNLBP) is a public health issue. Dysfunctions in muscle activation and spinal stability are estimated to directly impact pain intensity. Additionally, senior women experience greater decline in muscle function due to aging, rendering this demographic more susceptible to developing low back pain. The aim of this study was to analyze the correlation between core muscle instability, strength, and endurance with pressure pain threshold in senior individuals with CNLBP. METHODS: This is a quantitative observational study, with a descriptive cross-sectional design, conducted on women aged 60 to 79 years. The pressure pain threshold (PPT). The pressure pain threshold (PPT) was assessed using a pressure algometer applied to the paravertebral and anterior tibial musculature. Trunk instability was assessed on both a stable and an unstable seat, positioned atop a force platform that provided real-time displacement of the pressure center. Maximum isometric strength and endurance of trunk flexors and extensors were assessed using the McGill protocol. Person's correlations coefficient (r) was calculated, and the data were presented as mean and standard deviation. The significance level was set at p<0.05. RESULTS: This study included 49 senior women (67,3±5,6 years; body mass index of 28,5±5,2 kg/m2; pain intensity of 4,6±2,3 on a 0-10scale). No correlation was observed between PPT at L3, L5 and TA with lumbar instability, maximum isometric strength and trunk muscle endurance. CONCLUSION: In this study, no correlation was found between lumbar instability, maximum isometric strength and trunk muscle endurance with the PPT in senior women with CNLBP.

RESUMO JUSTIFICATIVA E OBJETIVOS: A dor lombar crônica inespecífica (DLCI) é um problema de saúde pública. Estima-se que disfunções na ativação muscular e na estabilidade da coluna possam repercutir diretamente na intensidade da dor. Além disso, em decorrência da idade, as mulheres idosas apresentam maior declínio na função muscular, tornando esse público mais suscetível a desenvolver a dor lombar. O objetivo deste estudo foi analisar a correlação entre instabilidade, força e resistência dos músculos do core com o limiar de dor por pressão em idosas com DLCI. MÉTODOS: Trata-se de um estudo observacional quantitativo, com delineamento transversal descritivo, realizado em mulheres com idade entre 60 e 79 anos. O limiar de dor por pressão (LDP) foi avaliado com um algômetro de pressão na musculatura paravertebral (bilateralmente ao processo espinhoso nível de L3 a L5) e cinco cm abaixo da tuberosidade da tibial direita no tibial anterior. A instabilidade de tronco foi avaliada em um assento estável e outro instável, posicionados sobre uma plataforma de força para análise do deslocamento do centro de pressão em tempo real. A força isométrica máxima e a resistência de flexores e extensores do tronco foi avaliada por meio do protocolo de McGill. Foi calculado o coeficiente de correlação de Pearson (r), os dados foram expressos em média e desvio padrão e o valor considerado significativo quando p<0,05. RESULTADOS: Participaram deste estudo 49 mulheres (67,3±5,6 anos; índice de massa corporal de 28,5±5,2 kg/m2; intensidade da dor 4,6±2,3 em uma escala de 0- a 10). Não foi encontrada correlação entre o LDP em L3, L5 e TA com instabilidade lombar, força isométrica máxima e resistência dos músculos do tronco. CONCLUSÃO: Não foi encontrada, neste estudo, uma correlação entre a instabilidade lombar, a força isométrica máxima e a resistência dos músculos do tronco com o LDP em mulheres idosas com DLCI.

Functional Training and Dual-Task Training Improve the Executive Function of Older Women.

Functional training (FT) is a type of multicomponent training with emphasis on activities of daily living that stimulate different physical capacities in only one session. Dual-task training (DTT) is a type of training that simultaneously applies cognitive and motor stimuli. We investigated the effects of sixteen weeks of FT and DTT and eight weeks of detraining on older women's inhibitory control, working memory, and cognitive flexibility. Sixty-two older women (66.9 ± 5.4 years; 27.7 ± 3.9 kg/m2) completed a 16-week intervention program comprising the FT (n = 31) and DTT (n = 31), and 43 returned after the detraining period. We used the Stroop Color Word Color test to evaluate inhibitory control, the Corsi Block Test to assess working memory, and the Trail Making Test to evaluate cognitive flexibility. Only DTT reduced the congruent response time between the pre-test and post-test (d= -0.64; p < 0.001), with no difference between the post-test and the detraining values (d = 1.13; p < 0.001). Both groups reduced the incongruent response time between the pre-test and post-test (FT: d = -0.61; p = 0.002; DTT: d= -0.59; p = 0.002) without a difference between groups. There were no significant differences in working memory and cognitive flexibility. Sixteen weeks of FT and DTT increased the inhibitory control of older women but not the working memory and cognitive flexibility, and these effects persisted after eight weeks of detraining.

Neuroendocrine effects of a single bout of functional and core stabilization training in women with chronic nonspecific low back pain: A crossover study.

Exercise-induced hypoalgesia (EIH) is characterized as the pain reduction after an exercise session and it seems to be related to the release of plasma ß-endorphin. In this sense, the core stabilization training (CT) has been suggested for patients with chronic nonspecific low back pain (CNSLBP), but it is unclear whether it induces EIH. Patients with CNSLBP have neuromotor dysfunctions that can affect the performance of functional tasks, thus, performing functional training (FT) could improve motor control and promote EIH, since functional training uses multi-joint exercises that aim to improve the functionality of actions performed in daily life. EIH is usually assessed using quantitative sensory tests (QST) such as conditioned pain modulation, pressure pain threshold, and temporal summation. Thus, the sum of parameters from quantitative sensory tests and plasma ß-endorphin would make it possible to understand what the neuroendocrine effects of FT and CT session are. Our study compared the acute effect of CT and FT on the EIH and plasma ß-endorphin release, and correlated plasma ß-endorphin with quantitative sensory testing in patients with CNSLBP. Eighteen women performed two training sessions (CT and FT) with an interval of 48 h between sessions. EIH was assessed by QST and plasma ß-endorphin levels. Results showed that only FT significantly increased plasma ß-endorphin (FT p < 0.01; CT p = 0.45), which correlated with pain pressure threshold (PPT) and conditioned pain modulation (CPM). However, QST values were not different in women with CNSLBP after CT or FT protocols. Plasma ß-endorphin correlated with PPT and CPM, however, the same did not occur with a temporal summation.