Core Strengthening Effects in Low Back Pain in Overweight Adults (CORE-BACK)

Effects of Core Strengthening on Mechanical Low Back Pain in Overweight Adults.

Mechanical low back pain is one of the most common musculoskeletal disorders among overweight adults and can lead to pain, disability, and reduced quality of life. Weakness of the core muscles may contribute to poor spinal stability and persistence of symptoms. Core strengthening exercises have been proposed as an effective treatment; however, evidence regarding their additional benefit over conventional physical therapy remains limited.

This randomized controlled trial aimed to determine the effects of adding core strengthening exercises to conventional physical therapy in overweight adults with mechanical low back pain. Sixty participants aged 25-45 years with a body mass index (BMI) of 25 kg/m² or greater and chronic mechanical low back pain lasting more than three months were randomly assigned to either an experimental group or a control group.

The experimental group received core strengthening exercises (planks, side planks, and superman exercises) in addition to conventional physical therapy, while the control group received conventional physical therapy alone. Both groups also received therapeutic hot packs and transcutaneous electrical nerve stimulation (TENS). Participants attended three treatment sessions per week for six weeks.

Primary outcomes included pain intensity measured by the Numeric Pain Rating Scale (NPRS), functional disability measured by the Oswestry Disability Index (ODI), and body fat percentage measured using the Jackson-Pollock skinfold method. Outcomes were assessed before and after the six-week intervention.

The study evaluated whether adding core strengthening exercises to conventional physical therapy provides greater improvements in pain, disability, and body fat percentage in overweight adults with mechanical low back pain.

Study Overview

• Status: Completed
• Conditions: Chronic Low Back Pain; Mechanical Low Back Pain
• Intervention / Treatment: Procedure: Core Strengthening Exercise Program + Conventional Physical Therapy; Procedure: Conventional Physical Therapy

Detailed Description

Mechanical low back pain (MLBP) is a common musculoskeletal condition and one of the leading causes of disability worldwide. Overweight and obesity increase the mechanical load on the lumbar spine, alter spinal biomechanics, and contribute to reduced physical function and persistent pain. Excess body weight, decreased physical activity, and weakness of the trunk musculature may further compromise spinal stability, increasing the likelihood of chronic low back pain.

Core muscles, including the transversus abdominis, multifidus, erector spinae, diaphragm, pelvic floor muscles, rectus abdominis, and internal and external oblique muscles, play an essential role in maintaining spinal stability and functional movement. Strengthening these muscles may improve trunk stability, reduce mechanical stress on the lumbar spine, decrease pain, and enhance functional ability. Although several studies have investigated core stabilization exercises, evidence regarding their effectiveness in overweight adults with mechanical low back pain remains inconclusive.

This study was designed as a single-blinded randomized controlled trial to compare the effects of conventional physical therapy alone with conventional physical therapy combined with core strengthening exercises in overweight adults with chronic mechanical low back pain.

A total of 60 participants aged 25-45 years with chronic mechanical low back pain of more than three months' duration, BMI ≥25 kg/m², body fat percentage greater than 25%, and Numeric Pain Rating Scale scores below 7 were enrolled. Participants with non-mechanical low back pain, previous lumbar spine surgery, spinal fractures, spondylolisthesis, osteoporosis, neurological disorders, metabolic diseases, spinal trauma, or other serious spinal pathology were excluded.

Eligible participants were randomly allocated into two equal groups.

Experimental Group

Core strengthening exercises:

Plank Side plank Superman exercise

Conventional exercises:

Bridging Knee-to-chest exercise Back extension Pelvic rotation

Baseline physical therapy:

Therapeutic hot pack Continuous Transcutaneous Electrical Nerve Stimulation (TENS) for 10 minutes

Control Group

Conventional exercises:

Bridging Knee-to-chest exercise Back extension Pelvic rotation

Baseline physical therapy:

Therapeutic hot pack Continuous TENS for 10 minutes

Participants attended three supervised treatment sessions per week for six consecutive weeks (18 treatment sessions). Each exercise was performed for 10 repetitions with a 10-second hold and standardized rest intervals. Participants were advised to avoid heavy physical activities throughout the intervention period.

Outcome measures were assessed at baseline and after completion of the intervention. Pain intensity was evaluated using the Numeric Pain Rating Scale (NPRS). Functional disability was assessed using the Oswestry Disability Index (ODI). Body fat percentage was measured using the Jackson-Pollock three-site skinfold method.

Data analysis was performed using SPSS version 21. Normality of data distribution was assessed using the Kolmogorov-Smirnov test. Because several variables were not normally distributed, non-parametric statistical tests were used. Between-group comparisons were analyzed using the Mann-Whitney U test, while within-group pre- and post-treatment comparisons were analyzed using the Wilcoxon Signed-Rank test. Statistical significance was established at a p-value less than 0.05.

The study investigated whether the addition of core strengthening exercises to conventional physical therapy would provide greater reductions in pain intensity, disability, and body fat percentage than conventional therapy alone in overweight adults with chronic mechanical low back pain. The findings are expected to contribute to evidence-based rehabilitation strategies for managing mechanical low back pain in overweight individuals and assist clinicians in selecting effective exercise interventions for this patient population.

• Study Type: Interventional
• Enrollment (Actual): 60
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Pakistan
  • Punjab Province
    • Rawalpindi, Punjab Province, Pakistan
      • Elite Physical Therapy Centre

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

Male and female participants. Age between 25 and 45 years. Diagnosed with chronic mechanical low back pain lasting more than 3 months. Body Mass Index (BMI) ≥ 25 kg/m² (overweight or obese). Body fat percentage > 25%. Numeric Pain Rating Scale (NPRS) score < 7 at baseline. Able and willing to provide written informed consent. Willing to participate in the complete 6-week intervention program.

Exclusion Criteria:

Non-mechanical low back pain. Acute low back pain. Previous lumbar spine surgery (e.g., laminectomy or discectomy). Spondylolisthesis. Osteoporosis or spinal fractures. Cauda equina syndrome. Current history of spinal trauma or surgery. Lumbar spine myelopathy. Diagnosed metabolic diseases. Neurological disorders affecting the spine or lower limbs. Any medical condition that would contraindicate participation in the exercise program.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Experimental Group (Core Strengthening + Conventional Physical Therapy); Participants assigned to the experimental arm received a combination of core strengthening exercises (plank, side plank, and superman exercises) together with conventional physical therapy exercises (bridging, knee-to-chest, back extension, and pelvic rotation). All participants also received a therapeutic hot pack and continuous transcutaneous electrical nerve stimulation (TENS) for 10 minutes. Treatment was provided three times per week for six weeks (18 sessions).	Procedure: Core Strengthening Exercise Program + Conventional Physical Therapy; Participants received a supervised exercise program consisting of core strengthening exercises (plank, side plank, and superman exercises) in addition to conventional physical therapy exercises (bridging, knee-to-chest, back extension, and pelvic rotation). Each exercise was performed for 10 repetitions with a 10-second hold. Participants also received a therapeutic hot pack and continuous transcutaneous electrical nerve stimulation (TENS) for 10 minutes before exercise. Treatment was provided three sessions per week for six weeks (18 sessions).; Procedure: Conventional Physical Therapy; Participants received conventional physical therapy consisting of bridging, knee-to-chest, back extension, and pelvic rotation exercises. Each exercise was performed for 10 repetitions with a 10-second hold. Participants also received a therapeutic hot pack and continuous transcutaneous electrical nerve stimulation (TENS) for 10 minutes before exercise. Treatment was provided three sessions per week for six weeks (18 sessions).
Active Comparator: Control Group (Conventional Physical Therapy); Participants assigned to the control arm received conventional physical therapy consisting of bridging, knee-to-chest, back extension, and pelvic rotation exercises. All participants also received a therapeutic hot pack and continuous transcutaneous electrical nerve stimulation (TENS) for 10 minutes. Treatment was provided three times per week for six weeks (18 sessions).	Procedure: Core Strengthening Exercise Program + Conventional Physical Therapy; Participants received a supervised exercise program consisting of core strengthening exercises (plank, side plank, and superman exercises) in addition to conventional physical therapy exercises (bridging, knee-to-chest, back extension, and pelvic rotation). Each exercise was performed for 10 repetitions with a 10-second hold. Participants also received a therapeutic hot pack and continuous transcutaneous electrical nerve stimulation (TENS) for 10 minutes before exercise. Treatment was provided three sessions per week for six weeks (18 sessions).; Procedure: Conventional Physical Therapy; Participants received conventional physical therapy consisting of bridging, knee-to-chest, back extension, and pelvic rotation exercises. Each exercise was performed for 10 repetitions with a 10-second hold. Participants also received a therapeutic hot pack and continuous transcutaneous electrical nerve stimulation (TENS) for 10 minutes before exercise. Treatment was provided three sessions per week for six weeks (18 sessions).

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Pain Intensity	Pain intensity will be assessed using the Numeric Pain Rating Scale (NPRS), an 11-point scale ranging from 0 (no pain) to 10 (worst imaginable pain). Lower scores indicate reduced pain intensity.	Baseline and after 6 weeks of intervention
Functional Disability	Functional disability will be measured using the Oswestry Disability Index (ODI). The ODI is a validated questionnaire that evaluates disability associated with low back pain. Lower scores indicate better functional status.	Baseline and after 6 weeks of intervention
Body Fat Percentage	Body fat percentage will be measured using the Jackson-Pollock three-site skinfold method with skinfold calipers. Changes in body fat percentage will be compared before and after the intervention.	Baseline and after 6 weeks of intervention

Collaborators and Investigators

• Sponsor: Ibadat International University, Islamabad
• Investigators: Study Chair: Dr Jawad Naveed, MS, Riphah College of Rehabilitation & Allied Health Sciences, Riphah International University, Islamabad

Study record dates

Study Major Dates

• Study Start (Actual): January 15, 2023
• Primary Completion (Actual): May 11, 2023
• Study Completion (Actual): June 30, 2023

Study Registration Dates

• First Submitted: July 10, 2026
• First Submitted That Met QC Criteria: July 22, 2026
• First Posted (Actual): July 27, 2026

Study Record Updates

• Last Update Posted (Actual): July 27, 2026
• Last Update Submitted That Met QC Criteria: July 22, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: Mechanical Low Back Pain; Overweight Adults; Conventional Physical Therapy; Core Strengthening; Superman Exercise
• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Back Pain; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Low Back Pain
• Other Study ID Numbers: RIPHAH/RCRS/REC/Letter- 01410

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Individual participant data (IPD) collected during this study will not be shared. The informed consent obtained from participants did not include permission for public sharing of individual-level data, and no data-sharing plan was established at the time of study initiation. De-identified aggregate study results are reported in the thesis and may be made available upon reasonable request to the corresponding investigator, subject to institutional policies and ethical considerations.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No