Low Back Extension Research Articles

Wrist, but Not Back, Isometric Contraction Induced Widespread Hypoalgesia in Healthy Participants.

Objective: Exercise may reduce pain sensitivity. This phenomenon called exercise-induced hypoalgesia is observed in different types of exercises and involves the activation of endogenous pain modulation systems. Although the effect of limb exercise on pain sensitivity has often been tested, few studies explored the impact of back exercises that are often used to treat low back pain. The main objective is to measure the effect of back-muscle exercise on pain sensitivity and compare it to the effect of a limb-muscle exercise.Methods: Twenty-three participants who were pain-free performed a 4-min wrist flexion isometric contraction followed by a 4-min low back extension, separated by a 20-min break. Pressure pain thresholds were tested at two low back (S1 spinous process, lumbar erector spinae muscle) and two wrist (capitate bone, wrist flexor muscles) sites before and after each exercise. For each exercise, sites were considered as remote or local in relation to the muscles contracted during the exercise. An independent sample of 11 participants was recruited to confirm the influence of low back extension on pain sensitivity.Results: Wrist exercise induced a larger increase in pain sensitivity than back exercise at the remote site. Only wrist exercise induced a hypoalgesia effect at both the local and the remote sites. Back exercise induced a similar effect in the independent sample.Conclusions: This study showed that back and wrist exercises induced a distinct effect on pain sensitivity in participants who were pain-free. The wrist exercise induced a systemic reduction in pain sensitivity (locally and remotely), whereas the back exercise did not. This differential effect may be present because wrist exercise induced most fatigue compared with the back exercise.

Patients With Becker Muscular Dystrophy Have Severe Paraspinal Muscle Involvement.

Introduction: Paraspinal muscles are important for gross motor functions. Impairment of these muscles can lead to poor postural control and ambulation difficulty. Little knowledge exists about the involvement of paraspinal muscles in Becker muscular dystrophy.Objective: In this cross-sectional study, we investigated the involvement of paraspinal muscles with quantitative trunk strength measure and quantitative muscle MRI.Methods and Materials: Eighteen patients with Becker muscular dystrophy underwent trunk, hip, and thigh strength assessment using a Biodex dynamometer and an MRI Dixon scan. Fourteen age- and body mass index-matched healthy men were included for comparison.Results: Muscle fat fraction (FF) of the paraspinal muscles (multifidus and erector spinae) was higher in participants with Becker muscular dystrophy vs. healthy controls at all three examined spinal levels (C6, Th12, and L4/L5) (p < 0.05). There was a strong and inverse correlation between paraspinal muscle FF and trunk extension strength (ρ = −0.829, p < 0.001), gluteus maximus FF and hip extension strength (ρ = −0.701, p = 0.005), FF of the knee extensor muscles (quadriceps and sartorius) and knee extension strength (ρ = −0.842, p < 0.001), and FF of the knee flexor muscles (hamstring muscles) and knee flexion strength (ρ = −0.864, p < 0.001). Fat fraction of the paraspinal muscles also correlated with muscle FF of the thigh muscles and lower leg muscles.Conclusion: In conclusion, patients with Becker muscular dystrophy demonstrate severe paraspinal muscular involvement indicated by low back extension strength and high levels of fat replacement, which parallel involvement of lower limb muscles. Assessment of paraspinal muscle strength and fat replacement may serve as a possible biomarker for both the clinical management and further study of the disease.

Biomechanical comparisons of back and front squats with a straight bar and four squats with a transformer bar

ABSTRACT The purpose was to quantify trunk and lower extremity biomechanics among back and front squats with a straight bar and four squats with different anterior-posterior load placements imposed by a transformer bar. Ten males and eight females performed six squat conditions: back and front squats with a straight bar, back and front squats with a transformer bar, and squats with more posteriorly or anteriorly placed loads with a transformer bar. A constant load of 70% of the participant’s one-repetition maximum in the straight-bar front squat was used. Kinematic and kinetic data were collected to quantify joint biomechanics at an estimated parallel squat position in the descending and ascending phases. Squats with more anteriorly placed load significantly decreased trunk flexion and pelvis anterior tilt angles with large effect sizes but increased low-back extension moments with medium to large effect sizes. Hip, knee, and ankle extension moments were generally similar among most conditions. Participants adjusted their trunk and pelvis to mediate the effects of load placements on low-back and lower extremity moments. While lower extremity loading was similar among different squats, the different trunk and pelvis angles and low-back moments should be taken into consideration for people with low-back impairment.

Brain functional connectivity changes by low back extension pain model in low back pain patients.

PurposeLow back pain (LBP) is a common ailment in most developed countries. Because most cases of LBP are known as ‘non-specific’, it has been challenging to develop experimental pain models of LBP which reproduce patients’ clinical pain. In addition, previous models have limited applicability in a steady-pain-state neuroimaging environment. Thus, this study aims to devise a low back pain model with a simple methodology to induce experimental LBP, which has similar pain properties to patients’ clinical pain, and to apply the model in a steady-pain-state neuroimaging study.MethodsOur low back extension (LBE) pain model was tested on 217 LBP patients outside the magnetic resonance imaging (MRI) scanner to determine the reproducibility of endogenous pain and the similarity to their own clinical pain (STUDY1), and applied in a steady-pain-state functional MRI study (47 LBP patients and 23 healthy controls) to determine its applicability (induced head motions and brain functional connectivity changes; STUDY2).ResultsBy the LBE pain model, 68.2% of the LBP patients reported increased LBP with high similarity of sensations to their own clinical pain (STUDY1), and the head motions were statistically similar to and correlated with those in resting state (STUDY2). Furthermore, the LBE model altered brain functional connectivity by decreasing the default-mode and the sensorimotor networks, and increasing the salience network, which was significantly associated with the intensity of the induced pain. Conversely, the healthy controls showed increased somatosensory network (but not of the cognitive pain processing).ConclusionOur investigations suggest that our LBE pain model, which increased LBP with high similarity to the LBP patients’ own pain sensation and induced patient-specific brain responses with acceptable head motion, could be applied to neuroimaging studies investigating brain responses to different levels of endogenous LBP.

Differential Influence of Acupuncture Somatosensory and Cognitive/Affective Components on Functional Brain Connectivity and Pain Reduction During Low Back Pain State.

The underlying mechanism of pain reduction by acupuncture is still unclear, because acupuncture treatment involves multidimensional factors. In this study, we investigated the differential influence of acupuncture components on brain functional connectivity and on pain reduction. We used a specific form of sham acupuncture (phantom acupuncture; PHNT), which only has a needling-credibility (a belief that they were treated with real acupuncture needles), while real acupuncture (REAL) has a somatosensory needling stimulation, as well as a needling-credibility. Forty-three patients with low back pain were randomized into the REAL group (n = 25) and the PHNT group (n = 18). They underwent two pain steady-state fMRI runs implemented by a low back extension (LBE) pain model (lifting the low back using air-cuff inflation) before and after REAL or PHNT stimulation. Subjective pain ratings, perceived throughout the LBE runs due to the posture, were reported (LBEpain). The regions of interest (ROI) were (1) the main nodes of the default mode network (DMN) – the medial prefrontal cortex (mPFC), posterior cingulate cortex (PCC), (2) the main nodes of the salience network (SN) – the anterior/posterior insular cortices (a/pINS), and (3) the low back-specific region of sensorimotor network (SMN), S1back. Significant reductions in LBEpain were observed in both groups (REAL = −1.02 ± 1.53, PHNT = −1.26 ± 2.20). In REAL group, decreased LBEpain was positively correlated with decreased functional connectivity between the mPFC and pINS (r = 0.58, P < 0.05). Reduced LBEpain in PHNT was negatively correlated with increased PCC–aINS connectivity (r = −0.48, P < 0.05) and tended toward positive correlation with decreased S1back–pINS connectivity (r = 0.44, P = 0.07). Our findings might suggest different brain mechanisms of observed pain reduction; REAL seems to involve detachment of the self from the sensory aspect of pain, while PHNT does to shift attention to self and disengages physical pain processing hubs. This exploratory study proposes a sham methodology to dissociate the influence of different acupuncture components in acupuncture research. Further studies need to be followed with more elaborated hypothesis, study design, and analysis considering various cognitive/affective factors for better understanding of brain mechanisms of pain reduction regarding the different acupuncture aspects.

A Pilot Study of Varying Thoracic and Abdominal Compression in a Reconfigurable Trunk Exoskeleton During Different Activities.

Trunk exoskeletons are a new technology with great promise for human rehabilitation, assistance and augmentation. However, it is unclear how different exoskeleton features affect the wearer's body during different activities. This study thus examined how varying a trunk exoskeleton's thoracic and abdominal compression affects trunk kinematics and muscle demand during several activities. We developed a trunk exoskeleton that allows thoracic and abdominal compression to be changed quickly and independently. To evaluate the effect of varying compression, 12 participants took part in a two-session study. In the first session, they performed three activities (walking, sit-to-stand, lifting a box). In the second session, they experienced unexpected perturbations while sitting. This was done both without the exoskeleton and in four exoskeleton configurations with different thoracic and abdominal compression levels. Trunk flexion angle, low back extension moment and the electromyogram of the erector spinae and rectus abdominis were measured in both sessions. Different exoskeleton compression levels resulted in significantly different peak trunk flexion angles and peak electromyograms of the erector spinae. However, the effects of compression differed significantly between activities. Our results indicate that a trunk exoskeleton's thoracic and abdominal compression affect the wearer's kinematics and muscle demand; furthermore, a single compression configuration is not appropriate for all activities. The study suggests that future trunk exoskeletons should either be able to vary their compression levels to suit different activities or should have the compression designed for a specific activity in order to be beneficial to the wearer.

The Effects of Hydraulic Resistance Exercise on Functional Fitness and Quality of Life in Frail Elderly

This study was to evaluate the effectiveness of hydraulic resistance exercise (HDRE) for frail elderly. Forty five participants were divided into exercise group (79±7.6 yr, 11 men, 14 women), and control group (76±7.9 yr, 11 men, 9 women). An exercise group was trained by 6 types of exercise: Knee extension (KE), knee flexion (KF), chest press (CPr), chest pull (CPu), low back flexion (LF), and low back extension (LE) 2 days/week. HDRE was consisted of 12-week supervised program, 50 min/day, and one set with an appropriate loading for 15 repetitions to fatigue. As a results, muscle strength and power were significantly increased between 16.6~27.1% and 18.9~81.2% in the KE, KF, CPr, CPu, and LF (p < .05). The functional fitness were also increased about 19~43% except for sit & reach test, and health related quality of life were improved about 15~24% in the sf-36v2 test (p<.05). However, there were no significant changes in the control group, and the HDRE is an effective form of resistance training that provides benefits using low and moderate intensity of training for frail elderly.

Effect of Mental Processing on Low Back Load While Lifting an Object

Biomechanical study using a 3D motion analysis system conducted in a laboratory setting. To determine the effect of mental processing on low back load during lifting. In addition to ergonomic factors such as frequent lifting, work-related psychosocial factors are significant in the onset of disabling back pain. Although the ergonomic effects on low back load while lifting have been investigated and are widely accepted in the workplace, few studies have investigated the effect of psychosocial factors on low back load while lifting. Thirteen healthy subjects lifted a box from the ground in 4 different lifting tasks in randomized order: (1) squat posture with knees flexed; (2) stoop posture with knees extended; (3) squat posture with mental processing using arithmetic tasks; and (4) stoop posture with mental processing using arithmetic tasks. We used a 3D motion analysis system and 4 force plates to record kinematic and kinetic data. We calculated dynamic triaxial low back joint moments and low back compression force as index parameters of low back load under these experimental conditions. Mental processing significantly increased peak low back compression force and low back extension moment, but not lateral flexion or rotation moment, while lifting in both lifting postures. Also, mental processing increased trunk bending angles in the squat posture. Although a tendency for decreased pelvic forward tilt was observed, mental processing did not significantly decrease forward pelvic tilt in the stoop posture. Mental processing during lifting tasks seems to affect both trunk and pelvis angles in the sagittal plane for squat and stoop postures, resulting in increased low back load. The present findings might help explain the effect of ergonomic demands of lifting tasks as well as psychosocial factors responsible for the onset of disabling back pain. 2.

Intensity Of Circuit Training In Community-dwelling Older Adults Using The Thera-band Exercise Station

A well-rounded exercise program is recommended for older adults to improve health and maintain independence. PURPOSE: This study was conducted to determine if a concurrent aerobic and resistance circuit exercise program using the Thera-Band exercise station (TBE) provides an adequate aerobic and resistance training stimulus. METHODS: Twenty-six apparently healthy, community-dwelling older men and women (68.4±6 yr) aged 60-83 years were recruited for this study. The exercise program was a 12-wk circuit training program, 3 sessions per wk, and 50 min per session which included 30 min of aerobic and resistance exercise. Thirteen individual exercise stations were designed to perform resistance exercise and 13 aerobic dancing stages were arranged alternatively in a circuit manner. All exercises were performed by subjective voluntary effort of the participants. Heart rate reserve (HRR) was measured using a portable monitor during exercise. Resistance exercise was performed with elastic resistance on the TBE and force production was evaluation using the equation of Page et al. (2000). A rating of perceived exertion (RPE) was determined during both aerobic and resistance exercises. The first stage was 1 to 4 wk, the second stage was 5 to 8 wk, and final stage was 9 to 12 wk of the program. Exercise intensity was determined during stages 2 and 3. RESULTS: Mean HRR during aerobic dance exercise was 50 to 60% (stage 2: 52±14%; stage 3: 61±14%). HRR also increased from stage 2 to stage 3. Means for repetitions, force, and RPE during resistance exercise were 20 times/30sec, 8.4kg, and 13 in squat; 27, 3.5, and13 in arm curl; 26, 3.2, and 13 in elbow extension; 25, 2.2, and 13 in lateral rise; 26, 5.8, and 13 in upright row; 16, 2.9 and 12 in low back extension; and 29, 2.9, 12 in twist, respectively, during stage 3. CONCLUSIONS: Exercise intensity during TBE training provided an adequate aerobic stimulus as participants were exercising at 60% HRR. Participants were also able to achieve a low to moderate intensity during resistance exercise. These data have relevance to activity counseling in community-dwelling healthy older adults who desire to improve their cardiorespiratory and muscular fitness.

Pre-season screening of core muscle balance and control tests in the lumbar spine in professional road cyclists can we prevent uncontrolled movement?

BackgroundAsymptomatic musculoskeletal function, normal range of joint motion and normal muscle strength are considered not adequate star points to design a prevention injury program.ObjectiveTo assess core muscle balance and control...

Spinal Manipulative Therapy Has an Immediate Effect on Thermal Pain Sensitivity in People With Low Back Pain: A Randomized Controlled Trial

Current evidence suggests that spinal manipulative therapy (SMT) is effective in the treatment of people with low back pain (LBP); however, the corresponding mechanisms are unknown. Hypoalgesia is associated with SMT and is suggestive of specific mechanisms. The primary purpose of this study was to assess the immediate effects of SMT on thermal pain perception in people with LBP. A secondary purpose was to determine whether the resulting hypoalgesia was a local effect and whether psychological influences were associated with changes in pain perception. This study was a randomized controlled trial. A sample of convenience was recruited from community and outpatient clinics. Thirty-six people (10 men, 26 women) currently experiencing LBP participated in the study. The average age of the participants was 32.39 (SD=12.63) years, and the average duration of LBP was 221.79 (SD=365.37) weeks. Baseline demographic and psychological measurements were obtained, followed by quantitative sensory testing to assess temporal summation and Adelta fiber-mediated pain perception. Next, participants were randomly assigned to ride a stationary bicycle, perform low back extension exercises, or receive SMT. Finally, the same quantitative sensory testing protocol was reassessed to determine the immediate effects of each intervention on thermal pain sensitivity. Hypoalgesia to Adelta fiber-mediated pain perception was not observed. Group-dependent hypoalgesia of temporal summation specific to the lumbar innervated region was observed. Pair-wise comparisons indicated significant hypoalgesia in participants who received SMT, but not in those who rode a stationary bicycle or performed low back extension exercises. Psychological factors did not significantly correlate with changes in temporal summation in participants who received SMT. Only immediate effects of SMT were measured, so the authors are unable to comment on whether the inhibition of temporal summation is a lasting effect. Furthermore, the authors are unable to comment on the relationship between their findings and changes in clinical pain. Inhibition of Adelta fiber-mediated pain perception was similar for all groups. However, inhibition of temporal summation was observed only in participants receiving SMT, suggesting a modulation of dorsal horn excitability that was observed primarily in the lumbar innervated area.

Eight-Week Traditional Mat Pilates Training-Program Effects on Adult Fitness Characteristics

We investigated responses of adult, novice practitioners (n = 9) to an 8-week traditional mat Pilates program (P) that met 1 hr/day three times/week. Classes consisted primarily of beginner and intermediate level exercises. Compared to an active control group (C; n = 13) that showed no improvements, those in P significantly (p < .05) improved relative body fat (-1.2%BF), sit-and-reach (+7.5 cm), shoulder reach (+6.9 cm), curl-up (+14 reps), and low back extension (+7 reps) scores, as well as circumferences at the waist (-2.7 cm), chest (-1.7 cm), and arm (-0.5 cm). Baseline differences were noted only for curl-ups and low back extensions, with P being lower than C. Body composition, muscular endurance, and flexibility significantly improved after 8 weeks of traditional mat Pilates.

The Effects of a Supervised Resistance-Training Program on Special Olympics Athletes

To examine the effects of a resistance-training program on athletes with intellectual disabilities (ID). 2-way (2 x 2), repeated-measures analysis of variance on 2 groups (males and females); 30 Special Olympics (SO) athletes, age 16-22 (16 males, 14 females). INTERVENTION/OUTCOME MEASURES: Resistance training, twice per week, for 3 months on Med-X weight equipment. Exercises tested: chest press, abdominal crunch, seated row, overhead press, seated dip, lower back extension, and biceps curl. The weight lifted and the number of repetitions performed were used to determine predicted 1-repetition max (1RM). All participants as a group increased significantly in predicted 1RM for each exercise performed. Males were stronger than females for 5 of the 7 exercises. A significant interaction effect between genders was demonstrated for the seated dip. Significant strength gains can be accomplished by adolescents with ID via a supervised resistance-training program.

Truncus endurance, hip and ankle mobility and aerobic fitness in 15‐year‐old Norwegian adolescents in 1968 and 1997

This study compared the physical performance of adolescents in 1997 and 1968. The material included 1329 15-year-old Norwegian adolescents in Akershus county in Norway in 1968, and 1105 15-year-old adolescents in the same region in 1997. The investigations were supervised by the same conductor on both occasions, and used identical physical tests. The test battery included dynamic endurance of abdominal and low back muscles, hip flexion, ankle dorsiflexion and aerobic fitness. Compared with 1968, low back extension endurance in 1997 was almost 10% lower in both genders, the endurance of the abdominal muscles was 4.8% poorer among boys and 8.1% higher among girls and the ratio between abdominal and low back extension endurance was 11.8% higher among boys and 26.4% higher in girls. Compared with 1968, hip flexion in 1997 was 8.3% higher in girls, while ankle dorsiflexion and aerobic fitness in boys were 15% and 13.4% poorer, and 4.8% poorer and 2.5% higher in girls, respectively. The data indicate a general decline during one generation in physical performance among boys, a decline in low back endurance, truncus balance and ankle mobility among girls and in a higher abdominal endurance among girls.