نوع مقاله : مقاله پژوهشی
نویسندگان
1 دانشجوی کارشناسی ارشد، گروه توانبخشی ورزشی، دانشکده علوم ورزشی، دانشگاه بوعلی سینا، همدان، ایران
2 استاد، گروه توانبخشی ورزشی، دانشکده علوم ورزشی، دانشگاه بوعلی سینا، همدان، ایران
3 دانشجوی دکتری، گروه توانبخشی ورزشی، دانشکده علوم ورزشی، دانشگاه بوعلی سینا، همدان، ایران
4 دکتری، گروه توانبخشی ورزشی، دانشکده علوم ورزشی، دانشگاه بوعلی سینا، همدان، ایران
کلیدواژه‌ها
موضوعات
عنوان مقاله English
نویسندگان English
Background and Purpose
Chronic non-specific low back pain (CNLBP) is a highly prevalent and disabling condition, defined by persistent pain lasting more than three months without a clear underlying pathology. It affects a significant proportion of the adult population and increasingly, women in middle age, with substantial impacts on daily function, work productivity, and quality of life. The prevalence and chronicity of CNLBP highlight the need for targeted interventions that address both the biomechanical and neuromuscular contributors to pain and disability.
A growing body of evidence suggests that altered spinal alignment—particularly in the sagittal plane—is common in patients with CNLBP. These postural deviations, such as increased thoracic kyphosis and lumbar lordosis, contribute to abnormal loading patterns on the spine, leading to muscle weakness, soft tissue shortening, and further functional impairment
. Poor spinal alignment is not only a risk factor for the development and persistence of LBP but also complicates rehabilitation by perpetuating faulty movement patterns and instability.
Subgrouping patients with CNLBP according to their mechanical and alignment characteristics can help clinicians tailor treatment strategies, optimize exercise dosage, and determine intervention duration for improved clinical outcomes. Among the various therapeutic approaches, core stability exercises (CSE) and abdominal hollowing (AH) have gained prominence. CSE targets the activation and co-contraction of deep local trunk muscles, such as the transversus abdominis and multifidus, which are essential for segmental spinal stability and postural control
. AH is a specific maneuver that further isolates and activates these deep stabilizers while minimizing overactivity of superficial global muscles.
The current study was designed to investigate the effects of an eight-week program combining CSE and AH on the sagittal alignment of the thoracic and lumbar spine in women with CNLBP. The hypothesis was that this combined intervention would restore more neutral spinal alignment, reduce pain, and improve function by enhancing the recruitment and coordination of deep postural muscles.
Methods
Thirty women with CNLBP, aged 30–60 years, participated in this randomized controlled clinical trial. The sample size was determined using G*Power software, targeting a type I error of 0.05 and a type II error of 0.20 (80% power), with a minimum of 26 subjects required and 30 enrolled to account for potential attrition. Participants were recruited from orthopedic clinics in Hamedan province and screened by an orthopedic physician to confirm CNLBP diagnosis and eligibility.
Inclusion criteria were:
Visual Analogue Scale (VAS) pain score ≥ 45
Oswestry Disability Index (ODI) ≥ 25
No prior spinal surgery
CNLBP duration > 12 weeks
Exclusion criteria included pain in other body regions, limb deformities, recent use of painkillers, physical therapy within the past year, and specific diagnoses such as sciatica, spondylolysis, or vertebral fractures.
Thoracic kyphosis and lumbar lordosis angles were measured using a 60 cm flexible ruler while standing, a reliable and non-invasive method for spinal curvature assessment. After baseline assessment, participants were randomly assigned to an experimental group (CSE + AH) or a control group (no intervention).
The intervention consisted of an eight-week program, with sessions three times per week. Each session included 40 minutes of CSE and 20 minutes of AH. CSE progressed from isometric contractions in low-load positions to dynamic, multi-joint activities emphasizing deep muscle co-contraction. AH exercises focused on isolated activation of the transversus abdominis and multifidus, with attention to maintaining a neutral spine and minimizing superficial muscle involvement. Exercise progression was based on correct technique and spinal stability.
Statistical analysis was conducted using SPSS version 26. Analysis of covariance (ANCOVA) was used to compare pre- and post-intervention outcomes between groups, adjusting for baseline values. Significance was set at p < 0.05, and effect sizes were classified as small (0.01–0.059), medium (0.06–0.14), or large (>0.14).
Findings
The ANCOVA results revealed significant reductions in both thoracic kyphosis (p = 0.000, ηp² = 0.487) and lumbar lordosis (p = 0.000, ηp² = 0.654) in the experimental group compared to the control group, both representing large effect sizes
. Descriptive statistics indicated a 53% reduction in pain intensity, a 7% decrease in thoracic kyphosis angle, and a 6% reduction in lumbar lordosis angle following the intervention. These improvements were accompanied by enhanced postural control and functional capacity.
The results are consistent with prior research demonstrating that CSE and AH can restore neutral spinal alignment by activating deep postural muscles, correcting asymmetric loading, and reducing pain and disability
The study also supports the notion that faulty recruitment patterns of core muscles lead to increased spinal loading and postural instability, and that targeted exercise can reverse these maladaptive changes
.Discussion
This study highlights the therapeutic potential of combining CSE with AH for women with CNLBP. The intervention effectively restored more neutral sagittal alignment of the thoracic and lumbar spine, likely through improved activation and coordination of the transversus abdominis and multifidus muscles. The transversus abdominis, as the deepest abdominal muscle, plays a crucial role in controlling intervertebral motion and stabilizing the lumbar spine through its attachment to the thoracolumbar fascia
. When contracted, it increases tension in the fascia, acting as a natural back belt and enhancing spinal stability.
The findings align with the broader literature, which emphasizes the importance of deep local muscle co-contraction for spinal stability and postural control
. Previous stabilization strategies focusing on posterior pelvic tilt have been shown to be less effective, as they often overactivate superficial muscles and move the spine away from its optimal neutral position
. In contrast, AH and CSE promote segmental stabilization and proprioceptive restoration, leading to better outcomes in pain relief and functional improvement.
Furthermore, the significant reductions in pain and spinal curvature angles observed in this study are supported by other clinical trials demonstrating the superiority of core stabilization exercises over routine physical therapy in managing non-specific low back pain
. The improvements in postural alignment and pain reduction underscore the value of exercise therapy as a primary treatment for CNLBP, as recommended by European guidelines
.Conclusion
The combination of core stability exercises and abdominal hollowing is highly effective in restoring neutral spinal alignment, reducing pain, and improving function in women with chronic non-specific low back pain. By targeting deep postural muscles and minimizing superficial muscle overactivity, this approach reduces spinal loading, enhances motor control, and corrects faulty movement patterns. The results support the integration of CSE and AH into rehabilitation protocols for CNLBP, with particular emphasis on activating the transversus abdominis and multifidus to optimize lumbar-pelvic-hip stability and postural alignment.
Article Message
Spinal alignment is influenced by the interaction of adjacent segments within the kinetic chain. Core muscle coordination is essential for motor control and spinal stability. Exercises targeting the diaphragm, pelvic floor, transverse abdominis, and multifidus muscles enhance lumbar-pelvic-hip stability and improve postural alignment. This study underscores the therapeutic potential of CSE combined with AH in managing CNLBP.
کلیدواژه‌ها English
