Effectiveness of Core Strengthening and Lower Limb Exercises to Improve Body Movements in College Students with Chronic Low Back Pain: A Pilot Study

Introduction

Recurring lower back pain (LBP) causes 20 to 30 percent of cases of chronic lower back pain (CLBP), which progresses from acute to subacute to chronic.¹ It can be better understood why LBP may occur based on gender distinction because women are more likely to be vulnerable to negative emotions and to experience pain than men.² The physiological changes in the menstrual cycle, a lack of muscle power that frequently results in poor sitting postures, and primary dysmenorrhea are possible explanations for this discrepancy in females.

One of the most frequent causes of back pain in students is sitting incorrectly for extended periods of time while studying or attending lectures. Students frequently stoop to improve their focus on their books and laptops, which causes the spine to expand out of its normal position, resulting in back pain. The shallow abdominal and trunk muscles are a major contributing factor.^3,4 The deep trunk muscles, such as the transversus abdominis and lumbar multifidus, losing strength or having poor control of movement is another contributing factor to CLBP. The trunk muscular tissues maintain the lumbopelvic region's mobility and stability during physical activity, therefore individuals with low back pain frequently experience alterations in trunk muscle activity, especially in the lumbar multifidus and transversus abdominis. Non-specific low back pain (NSLBP) patients have diminished postural control, which is essential for carrying out functional tasks.⁵ Training for core strength focuses on the deep trunk muscles.⁶ Strengthening exercises (STE) are widely used as part of LBP treatment. Strengthening exercises are suitable for those with subacute or chronic NSLBP because they stimulate the superficial trunk muscles that absorb tension from loads.^7,8 Through the control and strengthening of the global trunk muscles, these exercises are intended to increase total spinal stability.

The lumbar spine's stability is significantly influenced by the lower limb muscles, particularly the hip muscles.⁹ The transfer of forces between the lower limbs and the lumbopelvic region can be facilitated by the strength and appropriate activation of the lower limb muscles.^10,11 Despite studies showing the connection between the forces produced by the hip and lumbar spine during functional activities, there are differences in the literature regarding the role of lower limb muscles in lumbar stability and how well these muscles function in people with chronic low back pain.^11,12

Seven distinct fundamental movements that were once recognized as the basis for more complex and dynamic movements are evaluated as part of the Functional Movement Screen (FMS), a thorough evaluation technique. The FMS is made to test how well kinetic chain mobility and stability interact, which is required to carry out both basic and functional movement patterns. Given that CLBP patients typically exhibit impaired mobility, core stability, and coordination, the FMS may be an effective technique for detecting movement abnormalities in these patients.¹³

The study's goal was to use the FMS test to determine the effectiveness of core strengthening and lower limb exercises in improving postural control, body and functional movements in college students with chronic low back pain.

Materials and Methods

A pilot interventional study was conducted involving 15 university college female students aged between 20 – 30 years. Participants who experienced chronic low back pain for more than three months, having score of 16 or less in functional movement screen test and no pain during testing were included in the study. Participants who had history of surgery, traumatic lesion of spine, and those not willing to participate were excluded from the study. The duration of the study was four weeks.

Procedure 

A brief introduction about the study procedure was given to all the participants. The inclusion and exclusion criteria were used to recruit participants, and a preliminary analysis including demographic information was completed. The intervention’s main component was the implementation of core strengthening and lower extremity exercises for 45 minutes for 20-30 repetitions and four days a week, for four weeks.

Outcome measure

Functional movement screen (FMS)

Using the FMS test, functional movement screen patterns were assessed. The deep squat, the hurdle step, the inline lunge, the shoulder mobility, the active straight leg lifts, the push-up, the trunk stability, and the rotary stability are the seven fundamental functional patterns where the FMS finds limitations.

Each exam was given a score between 0 and 3, with a maximum score of 21. Each test was graded on a 4-point (0–3) scale, with the lowest score utilized for tests that involved measuring the left and right sides to produce a final score out of 21. A score of 3 was assigned if the patient demonstrated a functional movement pattern without any movement compensation. A score of 2 was awarded if the individual made a functional movement pattern while compensating in any way. The subject received a score of 1 if they were unable to perform or finish the test in accordance with the published recommendations, whereas a score of 0 was given for individuals who experienced pain while moving or while completing a clearing test. The FMS scores before and after a four-week program of lower extremity and core strengthening exercises were compared.

Intervention

Core strengthening and lower extremity exercises

Participants were required to complete a four-week program for strengthening their lower extremities and core that included four sessions per week under supervision, each lasting 45 minutes and requiring 20 to 30 repetitions of each exercise.

The exercises included strength and mobility of spine and lower extremities. In the fourth week, participants had to perform exercises which included crook lying with tummy tucks for transverse abdominis and lumbar multifidus, oblique crunches for internal and external obliques and trunk rotation, bridging for gluteus maximus, hamstrings and quadriceps and pelvic movement, clamshell for gluteus medius, gluteus maximus and hip external rotators and hip rotation, squats for gluteus maximus, quadriceps and hip, knee and ankle movements, heel raises for gastrocnemius and ankle movements.

Results

The present study was conducted among 15 college students with chronic low back pain. To determine the significance of the difference between the outcome measure pre and post exercise, a paired t test was utilized.

Table 1 shows the mean and standard deviation of functional movement screen test pre and post treatment which were 16±0.92 and 20.47±0.64, respectively. Paired t test was used to determine the difference between pre and post treatment. t was found to be 33.5 and was statistically significant (P=0.000).

Discussion

Segmental stabilization exercises enhance spine stability by concentrating on the transversus abdominis and lumbar multifidus.¹⁴ By breathing normally for 10 seconds while carrying out 10 contractions, motor control was employed to contract the muscles (for instance, an abdominal draw-in movement while exhaling).

For CLBP individuals, learning core strength exercises is easier than learning traditional resistance training.¹⁵ Additionally, patients can exercise at home without any specific equipment, which is crucial since committed patients can benefit from home-based fitness regimens.

The diaphragm, transversus abdominis, and pelvic floor muscle, all work in harmony to create intra-abdominal pressure (IAP) during the contraction of the transverse abdominis (TrA), which acts as a pressurized balloon trying to separate the diaphragm and pelvic floor.

The lumbar spine is thus distracted, reducing the compressive stress on it. Multifidus serves as the spine's main intersegmental stabilizer. Due to its proximity to the vertebral column's center of rotation, it has a quick reaction time. Increased lordosis is a symptom of inefficient hip extension action. Chronic LBP was reported to have decreased multifidus activation, particularly Type-2 fiber atrophy, which was alleviated with stability training and function restoration.^16-18

The contraction of the gluteus maximus results in stability for the sacroiliac (SI) joint, establishing a self-bracing mechanism. The SI joint moves extremely little, which is crucial for performing its main job of transferring weight from the trunk to the legs. The sacroiliac joint, the pubic symphysis, the L5-S1 intervertebral joints, and the disc, all could be compromised as a result of excessive movement at the joint, which could cause SI joint dysfunction and low back pain. The gluteus maximus is believed to constrict the sacro tuberous ligament because of its proximal attachment, which gives the joint stability and decreases mobility.

Increased gluteus maximus fatigability in people with CLBP was reported by Kankaanpaa et al. Leinonen et al. also showed that people with non-specific CLBP were more susceptible to gluteus maximus fatigue, although they also found improvements in gluteus maximus firing latency following rehabilitation. Patients with low back pain frequently avoid uncomfortable movements, which leads to decreased gluteus maximus activity and diminished muscular endurance from lack of use. The gluteus maximus muscle contributes to altered hip extensor activation patterns and disrupted lumbo-pelvic rhythm, either of these have been linked to low back pain. Reduced low back pain is brought on by strengthening exercises that correct the gluteus maximus recruitment sequence and strengthen it.^19,20

Pain reduction, enhanced gluteus maximus strength, activation of transverse abdominis, higher back endurance, and improved lumbar spine adaptability can all be connected to the improvement in function. Exercises involving the gluteus maximus, the core muscle (the primary stabilizer), and flexibility, were all improved by repetition. With reduced pain perception, increased gluteus maximus strength, and increased back endurance, the individuals reported enhanced capacity to carry out their daily activities, which comprise components like pain severity, personal care, lifting, moving around, carrying objects, and traveling. Low back discomfort is prevented by the lumbar spine's stable and flexible balance.²¹

Weakness of the muscles in the lumbopelvic hip complex is a characteristic feature of low back pain. As compared to healthy controls, those with LBP at the hip are more likely to have decreased gluteus muscle strength, decreased hip abduction force output, and affected hip muscle recruitment. They are also more likely to have a distal-to-proximal activation of muscles pattern in the lower limb. These modifications in the strength and functionality of the gluteus medius muscle may cause LBP.

The lumbopelvic-hip complex is stabilized by one of the primary pelvic stabilizer muscle is the gluteus medius, which is crucial for controlling the femur and hip mobility in the frontal and transverse planes. The decrease in gluteus medius endurance demonstrated correlations between the onset of LBP and lumbopelvichip dysfunction and lower limb biomechanical impairment. The frontal plane location of the hip joint and transverse plane rotation during normal gait are produced and regulated by the gluteus medius. It is hypothesized that gluteus medius weakening causes a number of biomechanical alterations that affect the pelvis' stability and posture, which may then lead to LBP. Positive Trendelenburg signs can be seen clinically and are related to gluteus medius abduction weakness in the frontal plane, which is associated to the development of a Trendelenburg pattern of gait. As a result, when standing on one leg during the stance phase of locomotion, the pelvis shifts to the side that is not supported. On the intervertebral discs, this is hypothesized to result in an uneven distribution of pressure, which will subsequently put strain on the lumbar joints and cause LBP to arise. Similar to how decreased gluteus medius strength results in anterior rotation of the ipsilateral pelvis, decreased hip transverse plane control, and increased knee valgus, internal femoral rotation, and femoral adduction, are all thought to increase the risk of LBP.²²

Exercises involving the squat are a crucial part of physical treatment and sports training programs. Open chain workouts without weights are less useful than weight-bearing activities. Due to its complexity and ability to generate hip, knee, and ankle dorsiflexion, squatting is often used to examine muscular activation and motor control. Low back discomfort and the muscle activation in the lower limbs are related. When performing functional activities, the foot and ankle joints are the most distal elements of the closed kinetic chain. The posture of the trunk and the muscular activity are linked to the movement of the lower extremities when the foot is fixed on the ground during a kinematic closed chain movement like lifting or squatting. Alterations in the sagittal and frontal plane kinematics at the knee joint might result from restrictions in the range of motion of the ankle. Variations in foot and ankle posture may also have an impact on pelvic tilt. The foot and ankle could have an impact on how the lower limbs and the trunk are positioned.²³

People with CLBP are less stable in their posture and react to stressful situations more negatively. The members of group CLBP showed a significant improvement after the intervention, despite not having the chance to practice for the test or receive any triceps surae strengthening exercises throughout the training period. The distal function of heel-raising was aided by the proximal area's (trunk) enhanced stability as a result of the emphasis on strengthening the trunk and hip muscles. The CLBP patients' postural stability was greatly improved by the intervention because it reduced the severity of the pain and strengthened the stabilizer muscles.²⁴

The efficiency of the core stabilization muscles is vital, and in those who experience low back pain, the activation of the muscles is reduced, which is likely to degrade the standard of their motor patterns and reduce their FMS scores. Correct patterns can be avoided by maintaining core stability, positional alignment, dynamic postural balance, and strength throughout functional activities. The agonist and antagonist muscle’s usual length-tension relationship is maintained in the spine area during the motor movements of the functional chain, which results in optimum joint kinematics in the complex of the waist, hips, and thighs and the greatest stability for the movements of the lower limbs.²⁵

The study involved testing the effectiveness of core strengthening exercises and lower limb exercises among 15 female university college students who had chronic low back pain for four weeks and were found to be effective in improving postural control, body and functional movements which was statistically significant as shown in Table 1. The sample size of this study was less, being a pilot study and the findings require corroboration in a larger sample.

Conclusion

The study concluded that the core strengthening and lower limb exercises improved body and functional movements among college students with chronic low back pain. Movement is examined relative to movement health, movement competency and movement capacity. FMS tests movement in both unloaded and loaded conditions.

Conflict of Interest

None