Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Back Muscles”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,639 records · Page 91Linked to original sources
PubMed2001

Aerobic power and muscle strength among young and elderly workers with and without physically demanding work tasks.

The aim of the study was to investigate the effect of waste collection on the physical capacity of the workers. A total of 19 young and 28 elderly male waste collectors and two age-matched control groups participated. The aerobic power was estimated. The maximal isometric muscle strength was measured for back extension and flexion, shoulder elevation and abduction, and handgrip. The aerobic power was lower among the elderly workers compared with the young workers of both groups. No differences were found between waste collectors and control groups. A general tendency to larger muscle strength was found for both young and elderly waste collectors compared with the control groups. Waste collectors generally have a higher physical capacity than the control groups which is an indication of an early selection of the young waste collectors. With respect to the elderly waste collectors, the job seems to have a training effect especially for the shoulder muscles. No training effect is found for the aerobic power, and a discrepancy between work demand and individual aerobic capacity may occur among elderly workers resulting in a negative health effect unless the work task is evaluated according to age dependent criteria.

Adult↗
PubMed2006

Changes in pain, disability, and muscle activation patterns in chronic whiplash patients after ambulant myofeedback training.

OBJECTIVE: The aim of this exploratory study was to investigate changes in pain, disability, and muscle activation patterns in patients with chronic whiplash-associated disorder (WAD) after 4 weeks of myofeedback training. METHODS: Eleven WAD patients received ambulatory myofeedback training, during which upper trapezius muscle activation and relaxation were continuously recorded and processed for 4 weeks. Feedback was provided when muscle relaxation was insufficient. Pain in neck, shoulders, and upper back (Visual Analogue Scale), disability (Neck Disability Index), and muscle activation patterns during rest, typing, and stress tasks (surface electromyography) were assessed before and after the 4 weeks of training. RESULTS: Pain intensity decreased after 4 weeks of training. Clinically relevant changes were found with regard to pain in the neck and upper back region (55% of the patients), right shoulder (64%), and left shoulder (18%). A trend for decreased disability was found which was clinically relevant in 36% of the patients. A remarkable reduction was found in the Neck Disability Index items concerning headache and lifting weights. Overall, muscle activation was lower and muscle relaxation was higher after the training period with the largest differences during rest. Clinically relevant changes in surface electromyography parameters were found in a minority of patients. CONCLUSION: Four weeks of ambulant training may be beneficial in reducing pain and disability levels and normalizing muscle activation patterns in chronic WAD patients. A randomized-controlled study is recommended to further explore the effects of myofeedback training.

Activities of Daily Living↗
PubMedDate not supplied

Physical activity and four-year development of back strength in children.

Physical activity in children is important, both for its direct benefits and for establishing potentially lasting future behaviors. Understanding the development of back strength in children is also important, because decreased back strength is associated with low back pain in adults. We hypothesized the following: (1) a substantial percentage of children do not participate in adequate physical activity; (2) the development of back strength corresponds to the development of strength of appendicular muscles; (3) there is a positive relationship between physical activity and back strength. The study included 53 boys and 43 girls, aged 10 to 19 yr, who had undergone isometric strength testing 4 yr previously. From responses to a questionnaire, each child's level of physical and sedentary activity was calculated. Isometric back flexion and extension were measured with the same method used 4 yr previously. Statistical analyses were performed, including quadratic regressions to estimate the rate of increase in strength, height, and weight. The following results were found: (1) during the month before testing, 21 children participated in physical activity for less than 30 min/day; (2) the level of physical activity was significantly associated with back flexion and back extension (P = 0.03 for both); (3) the peak rate of increase in back strength occurred approximately 1 yr after the peak rate of increase in height. We conclude the following: (1) measures should be taken to increase the involvement of children in athletic activities; 2) physical activity may be important in the development of back strength; (3) the pattern of back strength development seems to be the same as that for development of muscles of the appendicular skeleton.

Adolescent↗
PubMed1988

Lactate dehydrogenases in Antarctic and temperate fish species.

1. The kinetics of lactate dehydrogenase (both forward and back reaction) in cardiac and skeletal muscle of an Antarctic teleost have been compared with a temperate teleost of comparable morphology and ecology. 2. In both species the forward reaction (pyruvate to lactate) is maximally activated at 2.5-4 mM pyruvate and inhibited above this level. 3. The Michaelis constant (Km) for pyruvate is not significantly different between muscle types or between species when measured at their normal environmental temperature. 4. Km for pyruvate varies with temperature in a positive direction. 5. The back reaction (lactate to pyruvate) is maximally activated by 12-16 mM lactate but only in skeletal muscle of the antarctic species is there inhibition above this level. 6. The Km for lactate is significantly (P less than 0.05) lower in the Antarctic fish cardiac muscle. 7. While the two species are morphologically and ecologically similar, differences at the biochemical level are discussed with respect to environmental temperature range and conservation of enzymic characteristics.

Animals↗
PubMed2004

Comparison of a high-intensity and a low-intensity lumbar extensor training program as minimal intervention treatment in low back pain: a randomized trial.

In a randomized, observer-blinded trial, the effectiveness of 3-month high-intensity training (HIT) of the isolated lumbar extensors was compared to low-intensity training (LIT). Eighty-one workers with nonspecific low back pain longer than 12 weeks were randomly assigned to either of the two training programs. Training sessions were performed on a modified training device that isolated the lower back extensors. Total intervention time was limited to 5-10 min (one or two training sessions) per week. Training effects were assessed in terms of changes in self-rated degree of back complaints, functional disability, and general, physical and mental health. Secondary outcomes in this study were muscle strength and fear of moving the back (kinesiophobia). Outcomes were evaluated at 1,2, 3, 6, and 9 months after randomization. The results showed that the two treatment programs led to comparable improvements in all outcome measures, except for mean isometric strength at 1, 2, 3, 6, and 9 months and kinesiophobia score at 2 and 9 months of follow-up. The high-intensity training group showed a higher strength gain (24 to 48 Nm) but a smaller decline in kinesiophobia (2.5 and 3.4 points, respectively), compared to the low-intensity training group. It can be concluded that high-intensity training of the isolated back extensors was not superior to a non-progressive, low-intensity variant in restoring back function in nonspecific (chronic) low back pain. In further research, emphasis should be put on identifying subgroups of patients that will have the highest success rate with either of these training approaches.

Adult↗
PubMed2003

Experimental muscle pain changes feedforward postural responses of the trunk muscles.

Many studies have identified changes in trunk muscle recruitment in clinical low back pain (LBP). However, due to the heterogeneity of the LBP population these changes have been variable and it has been impossible to identify a cause-effect relationship. Several studies have identified a consistent change in the feedforward postural response of transversus abdominis (TrA), the deepest abdominal muscle, in association with arm movements in chronic LBP. This study aimed to determine whether the feedforward recruitment of the trunk muscles in a postural task could be altered by acute experimentally induced LBP. Electromyographic (EMG) recordings of the abdominal and paraspinal muscles were made during arm movements in a control trial, following the injection of isotonic (non-painful) and hypertonic (painful) saline into the longissimus muscle at L4, and during a 1-h follow-up. Movements included rapid arm flexion in response to a light and repetitive arm flexion-extension. Temporal and spatial EMG parameters were measured. The onset and amplitude of EMG of most muscles was changed in a variable manner during the period of experimentally induced pain. However, across movement trials and subjects the activation of TrA was consistently reduced in amplitude or delayed. Analyses in the time and frequency domain were used to confirm these findings. The results suggest that acute experimentally induced pain may affect feedforward postural activity of the trunk muscles. Although the response was variable, pain produced differential changes in the motor control of the trunk muscles, with consistent impairment of TrA activity.

Adult↗
PubMed2006

[Influence of scald on the cytoskeleton of colonic smooth muscle cells of the rats].

OBJECTIVE: To investigate the changes in the morphology and cytoskeleton (CSL) content of the CSL in the colonic smooth muscle cells (SMCs) of rats in early postscald stage, so as to elucidate the mechanism of dysfunction of gastrointestinal motility. METHODS: Seventy Wistar rats were randomly divided into normal control (n = 10, without scald) , and scald ( n = 60, with 10 cm x 7 cm wound inflicted on the back) groups. The colonic smooth muscle tissue of 10 normal rats and scalded rats were harvested at 1, 3, 6, 12, 24 and 48 postscald hours( PSH) and divided into two parts: one for histologic examination, and the other for the detection of CSL changes in the colonic smooth muscle tissue by flowcytometry method. RESULTS: The electron microscope examination showed that the arrangement of cytoskeleton of SMC of the scalded rats during 1 to 3 PSH was disordered, and sparse, and the condensed area was uneven, with fragmentation. But the morphology and distribution of CSL gradually restored to normal state during 6 to 12 PSH, and it approached that of normal group at 48 PSH. The CSL content in the colonic smooth muscle tissue of scalded rats was obviously increased at 1 PSH (610+/-23) , decreased thereafter, evidently lower than that in control group at 3 PSH (92+/-17) , and then it started to increase at 12 PSH, exceeding the normal value at 24 PSH, and continued to rise until 48 PSH. There was significant difference in CSL content in the colonic smooth muscle tissue of the rats between scald and control group ( P < 0.05 or 0. 01). CONCLUSION: Changes in the morphology and CSL content in the colonic smooth muscle tissue can be observed at early stage after a scald, which imply the kinetic balance between damage and repair in the body. In addition, changes in CSL content in the colonic smooth muscle tissue may be important factors in producing colonic dysfunction, damage of intestinal wall structure, and dynamic abnormalities of the colonic smooth muscle.

Actins↗
PubMed1972

Comparison of carisoprodol, butabarbital, and placebo in treatment of the low back syndrome.

A double-blind study was carried out to determine the effectiveness of a muscle relaxant, carisoprodol, in the treatment of the low back syndrome, and to test whether this drug would produce any greater effect than an active sedative control. Forty-eight Mexican migrant farm laborers with acute lumbar strain and spasm were given either carisoprodol 350 mg, butabarbital 15 mg, or placebo, four times daily for four days, and then were rated on pertinent symptoms, the degree of limitation of motion (by an objective finger-to-floor test), and overall improvement. In the 43 patients who could be statistically analyzed, carisoprodol was shown to be significantly more effective than butabarbital or placebo in producing improvement of all factors rated. This result suggests that the effects of carisoprodol are not due solely to sedative action, but are also related to its muscle relaxant activity.

Adolescent↗
PubMed1990

Temporal stability of paraspinal electromyographic recordings in low back pain and non-pain subjects.

This paper presents the results of two studies in which bilateral surface EMG recordings of paraspinal muscle tension were measured in 29 lower back pain and 20 normal subjects in 6 different positions (standing, bending from the waist, rising, sitting with back supported, sitting unsupported, prone) on two occasions, and a comparison of the data from both studies. Measures were highly reliable when examined using analysis of variance procedures. Statistically significant reliability coefficients were obtained when the absolute values of the measures were examined, although in some instances less than 20% of the variance was explained. When examined as relative [percent change from baseline (prone) condition] values, differences between the two groups were observed: the normals were statistically more reliable than lower back pain subjects during every condition. Implications for clinical work and both basic and applied research are discussed.

Adult↗
PubMed1999

[The dissecting aortic aneurysm associated with polymyalgia rheumatica: a case report].

We report a patient with a dissecting aortic aneurysm associated with polymyalgia rheumatica (PMR). The patient is a 55-year-old Japanese man without a history of hypertension, diabetes mellitus and syphilis. He was admitted to an emergency hospital because of severe back pain, and was diagnosed as having a dissecting aneurysm of the descending aorta. After the admission, he began to notice severe muscle pain in his bilateral shoulder. Although his back pain gradually improved, his muscle pain progressively worsened, and his lower extremities were also involved. Then, he was introduced to our hospital. On neurological examination, he was alert and oriented. His cranial nerves were all intact. There was no muscle weakness nor sensory disturbance. Laboratory studies revealed that his erhythrocyte sedimentation rate was extremely high without elevation of the serum level of creatine phoshpokinase, rheumatoid factors and c-reactive protein. He was diagnosed as having PMR, and oral administration of prednisolone++ was started. Within several days, his muscle pain dramatically disappeared. As is known, there is a close relationship between PMR and temporal arteritis of giant cell arteritis. In general, PMR is a benign disease and responds well to steroid therapy, and prevalence of the giant cell arteritis is low in Japanese people. However, it should be kept in mind that the dissecting aneurysm is a relevant, severe complication of PMR because arteritis can be latently present in PMR.

Aortic Dissection↗
PubMed2001

Effect of gender, age, and anthropometry on axial and appendicular muscle strength.

OBJECTIVE: To assess age and gender differences in muscle strength. DESIGN: The strength of back extensors, upper limbs (grip), and lower limbs (knee extensors) was measured. Anthropometric measurements and body mass index also were assessed. RESULTS: Group comparisons were made for each decade. Back extensor strength (BES) in subjects aged 20 to 89 yr ranged from 93 to 832 N in men and from 71 to 440 N in women. BES peaked in the fourth decade for men and in the fifth decade for women. When the two genders were compared, muscle strength in women was less than that in men at all ages. At different decades, women's BES ranged from 54% to 76% compared with that of men's BES. There was a 64% loss of BES in men from the peak in their fourth decade (556 N) to the lowest level in their ninth decade (201 N). Women experienced a 50.4% loss from the peak in their fifth decade (306 N) to the lowest level in their ninth decade (152 N). CONCLUSIONS: Men had a greater loss of BES than women with increasing age. In both genders, there was more loss of BES than appendicular muscle strength. Reduction in BES in women coincided with increased body mass index in older age. In women, there was a negative correlation between body weight and level of physical activity, whereas this finding was not evident in men. Background factors related to a higher incidence of back pain, falls, and fractures, especially in women, may be a reduction in muscle strength, along with increasing age and body mass index. This cross-sectional study showed that physiologic reduction of muscle strength, which began early in life, later stopped and that muscle strength even improved, despite the aging process. Therefore, initiating strengthening exercises at any age is encouraged to prevent the impact of several age-related musculoskeletal challenges.

Adult↗
PubMed1975

Symposium on back problems in the horse. (2) The diagnosis of diseases of the horse's back.

A description of some of the clinical features of low back pain in the horse has been given and a number of methods for assisting diagnosis considered. As well as a complete clinical examination both at rest and during exercise, a useful diagnostic aid in some chronic cases was the injection of local anaesthetic into the interspinous spaces. A laboratory examination, including haematological and biochemical profiles, was undertaken in all cases. The serum enzymes GOT and CPK were particularly valuable as an aid to diagnosis in atypical tying-up. A technique for radiography of the vertebral column of the mid back in the standing position and of the pelvic and sacroiliac regions of the anaesthetised horse was described using a Siemens Triplex Optimatic 1023 machine. Some of the radiological features of the vertebral column were considered and a breakdown of the diagnosis of 110 referred back cases. The most important conditions included muscle strain, crowding and overriding of the dorsal spinous processes in the mid back, spondylosis, undue curvature of the spine and vertebral fractures.

Anesthesia, Local↗
PubMed2003

Trunk muscle onset detection technique for EMG signals with ECG artefact.

The timing of trunk muscle activation has become an important element in the understanding of human movement in normal and chronic low back pain populations. The detection of anticipatory postural adjustment via trunk muscle onsets from electromyographic (EMG) signals can be problematic due to baseline noise or electro-cardiac (ECG) artefact. Shewhart protocols or whole signal analyses may show different degrees of sensitivity under different conditions. Muscle activity onsets were determined from surface EMG of seven muscles for five trials before and after fatigue were examined in four subjects (n=280). The objective of this study was to examine two detection methods (Shewhart and integrated protocol (IP)) in determining the onsets of trunk muscles. The variability of the baseline amplitude and the impact of added Gaussian noise on the detected onsets were used to test for robustness. The results of this study demonstrate that before and after fatigue there is a large degree of baseline variance in the trunk muscles (coefficients of variation between 40-65%) between trials. This could be normal response to body sway. The IP method was less susceptible to false onsets (detecting onsets in the baseline window) 3 vs. 51%. The findings suggest the IP method is robust with large variance in the baseline if the signal to noise ratio is greater than six. In spite of the robustness of the algorithm, the findings would suggest that statistical assessments should be used to target trials for selective visual inspection for subtle trunk muscle onsets.

Abdominal Muscles↗
PubMed1994

Evidence for catecholamine-depleting action of fluoxetine.

The present investigation was undertaken to study the interaction of fluoxetine with 5-hydroxytryptamine (5-HT) and noradrenaline (NA) in rat anococcygeus muscle and vas-deferens. In rat anococcygeus muscle responses to NA were significantly potentiated after 30 min and 60 min incubation with fluoxetine (2.9 x 10(-9) M). The responses to 5-HT were however, inhibited after 30 min incubation with fluoxetine in this preparation. On rat vas-deferens also, the responses to NA were potentiated after 30 min incubation with fluoxetine. The response to 5-HT were not altered significantly. In rats pretreated with fluoxetine (5 mg/kg, ip) for seven days, the responses to NA were significantly potentiated in rat anococcygeus muscle. Whereas the responses to 5-HT and tyramine were significantly inhibited. The inhibited responses to 5-HT restored back to normal when the anococcygeus muscle was pre-incubated with NA for 30 min.

Animals↗