4. Discussion
Oswestry disability, LBP, pain
LORDOSIS, CONTRACTIONS
According to the results of this pilot study, adding ABB to SSE for patients with nonspecific CLBP was more effective on lumbar extensor strength, pain, and function than SSE alone. However, we were unable to confirm any benefit that the addition of ABB could have on the LLA.Although it is debated whether or not the LLA in the sagittal plane decreases or increases with age, a recent meta-analysis has reported that the LLA is significantly smaller in participants with LBP.To improve this reduced LLA, some researchers applied exercise intervention. In a study of 32 participants divided into an SSE group of 12 who used SSE for 12 sessions and a CG of 16 who used physical therapy alone, Hosseinfar et al reported that LLA recovery was confirmed in the SSE group.Spinal extensor strength also increased at all angles over time in both groups, but the interaction effect between group and time was confirmed at a spinal flexion angle of 60° and 72°. We provide evidence that these results are due to the activation of deep muscles, such as the IO and TrA, and an increase in IAP.Pain was improved over time in both the groups, and it was found that pain in the ABBG was better at 24 weeks. We believe that these results were demonstrated by deep muscle activation and increased IAP through ABB. Aleksiev et al previously performed a 10-year follow-up study designed as a randomized control trial and reported that spinal strength with ABB showed improvement in LBP compared with spinal strength without ABB, spinal flexibility, and spinal flexibility exercises with ABB.Finally, at 24 weeks after treatment, a significant difference was noted in the function, as evaluated by the Oswestry disability index, between the groups; it also showed the largest ES compared to other dependent variables. We believe that deep muscle activation, increased IAP, and concomitant contractions of the trunk muscles by ABB will contribute to stabilization of the spine and to improve pain and function in patients with LBP. Lee et al reported that the thickness of the IO, EB, and TrA increased, and the isometric strength of the lumbar extensor muscles improved as a result of applying straight leg raise with ABB.Based on these findings, the LLA may be improved with SSE, although this does not appear to provide evidence that the LLA is a determinant factor for differences in spine extensor strength, pain, and function. Instead, it can be concluded that these results were caused by the activation of deep spinal muscles and an increase in IAP caused by the addition of ABB to SSE.This study has several limitations. First, the strength of other muscle groups could not be evaluated, as we only measured the spine extension strength. Second, as the functional evaluation relied solely on a questionnaire and lacked physical assessment, making it challenging to evaluate the exact functional capabilities of patients. Finally, although we confirmed muscle strength in this study, we could not confirm morphological changes in the abdominal muscles due to the intervention, as measurements, such as muscle thickness evaluation, were not performed. In some studies, the TrA, IO, and external oblique muscles were examined using ultrasound during exercises such as ABB and abdominal hollowing in patients with CLBP, employing a reliable evaluation methodIn this pilot study, we were unable to confirm the reason behind the changes in the LLA and their effects on pain and function, although it was demonstrated that SSE results in the LLA changes in patients with CLBP.Moreover, adding ABB had no additional effect on changes in the LLA, although it was confirmed that it was more effective in improving spine extensor strength, pain, and function than SSE alone. Therefore, in this study, we recommend adding ABB to SSE to maintain lordosis in the lumbar spine and to improve symptoms in patients with CLBP.