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PubMed1996

Respiratory muscle strength after lung resection with special reference to age and procedures of thoracotomy.

Changes in respiratory muscle strength after lung resection were examined concerning age and procedures of thoracotomy. Maximum inspiratory (MIP) and expiratory (MEP) mouth pressure were measured before operation and 1, 2, 4, and 12 weeks after operation in 81 patients undergoing lung resection. In 48 patients undergoing pneumonectomy, lobectomy, or segmentectomy, patients older than 70 showed a significantly lower MIP and MEP before operation and throughout the postoperative period compared to younger ones (P < 0.01). Furthermore, the older patients showed a significantly lower percentage of postoperative MIP and MEP 4 weeks after operation than the younger ones (P < 0.01). In 31 patients undergoing lung wedge resection, patients undergoing limited thoracotomy (LT) and video-assisted thoracic surgery (VATS) showed significantly higher percentages of postoperative MIP and MEP than those undergoing posterolateral thoracotomy (PLT) 1 and 2 weeks after operation (P < 0.01 or 0.05). But there was no significant difference in the values between LT and VATS. We concluded that (1) elderly patients suffered respiratory muscle weakness before and after operation and their postoperative recovery of respiratory muscle strength was slower than in younger patients, and (2) VATS and LT resulted in more rapid recovery of respiratory muscle strength than PLT, but the difference between VATS and LT was not significant.

Adult↗

PubMed1999

The relation between bone mineral density, insulin-like growth factor I, lipoprotein (a), body composition, and muscle strength in adolescent males.

Osteoporosis is the most common metabolic bone disease. A low peak bone mass is regarded a risk factor for osteoporosis. Heredity, physical activity, and nutrition are regarded important measures for the observed variance in peak bone mass. Lp(a) lipoprotein is a well-known risk factor for atherosclerosis. Serum insulin-like growth factor I (IGF-I) has been found to be increased in males with early cardiovascular disease. In this study, we evaluated the association between bone mass, body constitution, muscle strength, Lp(a), and IGF-I in 47 Caucasian male adolescents (mean age, 16.9 yr). Bone mineral density (BMD) and body composition were measured by dual x-ray absorptiometry, muscle strength of thigh using an isokinetic dynamometer, IGF-I by RIA, and Lp(a) by enzyme-linked immunosorbent assay. IGF-I was only associated with Lp(a) (r = 0.38, P < 0.01). Lp(a) was related to total body (r = 0.40, P < 0.01), skull (r = 0.45, P < 0.01), and femoral neck BMD (r = 0.44, P < 0.01). Lp(a) was also related to fat mass (r = 0.34, P < 0.05) and muscle strength (r = 0.30-0.42, P < 0.05). After multiple regression and principal component (PC) analysis, the so-called PC body size (weight, fat mass, lean body mass, and muscle strength) was the most significant predictor of BMD (beta = 0.28-0.51, P < 0.05-0.01), followed by the so-called PC physical activity (beta = 0.28-0.38, P < 0.05-0.01, weight-bearing locations). However, the PC analysis confirmed that Lp(a) was an independent predictor of total body, skull, and femoral neck BMD (beta = 0.33-0.36, P < 0.01). The present investigation confirms that BMD, body size, and muscle strength are closely related and that the level of physical activity is a major determinant of BMD. However, the positive relation of Lp(a), a major risk factor for cardiovascular disease, to BMD has not previously been described. The importance of this observation has to be further investigated.

Adolescent↗

PubMed1997

Muscle strength and soft tissue composition as measured by dual energy x-ray absorptiometry in women aged 18-87 years.

Dual energy x-ray absorptiometry (DEXA) offers the possibility of assessing regional soft tissue composition, i.e. lean mass (LM) and fat mass: LM may be considered a measure of muscle mass. We examined age-related differences in LM, percentage fat (%fat) and muscle strength in 100 healthy non-athletic women aged 18-87 years. Relationships between muscle strength and leg LM in 20 elite female weight lifters and in 18 inactive women with previous hip fractures were also studied. The LM and %fat of the whole body, trunk, arms and legs were derived from a whole body DEXA scan. Isokinetic knee extensor strength (KES) and flexor strength (KFS) at 30 degrees.s-1 were assessed using an isokinetic dynamometer. The women aged 71-87 years had 35% lower KES and KFS than the women aged 18-40 years (P < 0.0001). Differences in LM were less pronounced. The LM of the legs, for instance, was 15% lower in the old than in the young women (P < 0.0001). In a multiple regression analysis with age, body mass, height and leg LM or KES as independent variables and KES or leg LM as the dependent variable, age was the most important predictor of KES (r(partial) = -0.74, P < 0.0001). The same applied to KFS. Body mass, not age, was the most important predictor of leg LM (r(partial) = 0.65, P < 0.0001) and of LM at all other measurement sites. The LM measured at different regions decreased equally with increasing age. The KES:leg LM ratio was negatively correlated with age (r = -0.70, P < 0.0001). The weight lifters had significantly higher KES:leg LM ratios than age-matched controls (+ 12%, P < 0.0001) and vice versa for the women with previous hip fractures (-36%, P < 0.0001). In conclusion, from our study it would seem that in healthy nonathletic women, age is a more important determinant of muscle strength than is LM as measured by DEXA. Muscle strengthening exercises and inactivity seem to have a considerably stronger influence on muscle strength than on LM.

Absorptiometry, Photon↗

PubMed2005

The effects of five-year growth hormone replacement therapy on muscle strength in elderly hypopituitary patients.

OBJECTIVE: Little is known of the long-term effects of GH replacement therapy on muscle strength in elderly adults with adult onset GH deficiency (GHD). In this study, the effects of 5 years of GH replacement therapy on muscle function were determined in adults over 60 years of age with adult onset GHD. DESIGN: A prospective, open-label, single-centre study. Patients Twenty-six (12 male and 14 female) consecutive hypopituitary adults with adult onset GHD, mean age 65.0 (range 61-74) years. MEASUREMENTS: Upper leg muscle strength was measured using a Kin-Com dynamometer. Right and left handgrip strength were measured using an electronic grip force instrument. RESULTS: The mean insulin-like growth factor-I (IGF-I) SD score increased from -1.10 at baseline to 1.21 at end of the study. Body weight was unchanged during the 5-year study. A sustained increase in lean body mass and a sustained reduction of body fat was observed as measured using dual-energy X-ray absorptiometry (DEXA). The GH replacement therapy induced a sustained increase in isometric (60 degrees ) knee flexor strength. After statistical correction for age and sex variables using observed/predicted value ratios, a sustained increase was also observed in concentric knee flexor strength at an angular velocity of 60 degrees /s, concentric knee extensor strength at 60 degrees /s and 180 degrees /s, and peak right handgrip strength. At baseline, knee flexor strength was 90-96% of predicted, knee extensor strength was 85-87% of predicted, and hand-grip strength was 74-80% of predicted values. At study end, knee flexor strength was 98-106% of predicted, knee extensor strength was 90-100% of predicted, and hand-grip strength was 80-87% of predicted values. CONCLUSION: Elderly patients with adult onset GH deficiency had decreased baseline muscle strength also after correction for age and sex. The 5-year GH replacement therapy normalized knee flexor strength and improved, but did not fully normalize, knee extensor strength and handgrip strength.

Absorptiometry, Photon↗

PubMed1993

Effect of aminophylline on respiratory muscle strength after upper abdominal surgery: a double blind study.

BACKGROUND: The effect of aminophylline on maximum respiratory muscle strength in patients undergoing upper abdominal surgery was investigated. METHODS: An open pilot study was performed in which aminophylline was administered continuously for 48 hours after surgery (protocol I). In a second group of subjects aminophylline was given for 24 hours after cholecystectomy in a double blind placebo controlled trial (protocol II). Twelve patients participated in the pilot study (group A) and 25 in protocol II of which 14 received aminophylline (group B) and 11 placebo (control, group C). Respiratory muscle strength was assessed by measuring mouth pressures during maximum static inspiratory and expiratory efforts. Forced expiratory volume in one second (FEV1), forced vital capacity (FVC), vital capacity (VC), inspiratory maximum pressures (PImax), expiratory maximum pressures (PEmax) were measured 24 hours preoperatively, PImax and serum theophylline 24 hours postoperatively, and FEV1, FVC, VC, PImax, PEmax, and serum theophylline 48 hours after surgery. RESULTS: FEV1, FVC, and VC decreased in all groups of patients at +48 hours. PImax fell at +24 hours and +48 hours but this decrease was significantly smaller in the two groups who received aminophylline than in the control group. PEmax showed a decrease at +48 hours but this reduction was similar in all three groups studied, independent of the treatment given. These data suggest that either aminophylline had a protective effect only on the inspiratory muscles or, most probably, that the effect of aminophylline was central, reducing the phrenic nerve inhibition induced by cholecystectomy and thus improving diaphragmatic function. CONCLUSIONS: Upper abdominal surgery decreases inspiratory and expiratory muscle strength and aminophylline has a protective effect only on inspiratory muscle function. This may have important clinical applications in minimising pulmonary complications after cholecystectomy.

Abdomen↗

PubMed1995

Measurement of muscle strength of the trunk and the lower extremities in subjects with history of low back pain.

STUDY DESIGN: Isokinetically measured muscle strength of the trunk and lower extremities was analyzed. OBJECTIVES: The causes of the weak trunk muscle strength of subjects with low back pain were studied. SUMMARY OF BACKGROUND DATA: Although it is a commonly accepted conclusion that subjects with low back pain have weaker trunk muscles than the normal population, there are no reports concerning muscle strength of the lower extremities in subjects with low back pain. METHODS: Ninety-eight male volunteers were divided into control groups and groups with low back pain. The total trunk strength and total knee strength were defined as the sum of the peak torques of trunk extension, flexion and rotation, and of bilateral knee extension and flexion, respectively. RESULTS: The total trunk and knee strength in the group with low back pain (281 +/- 170 and 301 +/- 132 Nm) were significantly lower than in the control group (543 +/- 124 and 441 +/- 123 Nm). The total trunk and knee strength were linearly correlated in both groups (r = 0.67 and 0.79). CONCLUSIONS: In the group with low back pain, the muscles of the trunk and the lower extremities were similarly affected; this can be attributed to generalized muscular weakness or psychologic factors, such as fear of injury.

Adolescent↗

PubMed2004

[Isokinetic thigh muscle strength in sports: a review].

There is growing evidence that isokinetic muscle strength, is one of the most common testing method why muscle strength is thought to be a major factor in athletic success and rehabilitation. A lot of publications during the last 20 years concerned the peak torque, the concentric ratio flexor/extensor, with comparison between males and females, sport specialties, young and old people. Isokinetic is also used for evaluation of knee disorders. The results are very useful after knee ligament surgery, less for femoro-patellar disorders and arthrosis. More recently some authors proposed the functional concept (eccentric flexors/concentric extensors ratio) as a predictive method for preventive muscle injuries or ACL lesions. They demonstrated more discomfort after muscle disorders with isokinetic eccentric testing, and proposed rehabilitation programs for prevention. However apart from a few situations, isokinetic testing does not fully predict functional measurements. It must be used with other techniques of evaluation (clinical methods and imagery).

Age Factors↗

PubMed2001

Pulmonary function tests, aerobic capacity, respiratory muscle strength and endurance of patients with rheumatoid arthritis.

Patients with rheumatoid arthritis (RA) show lower cardiorespiratory fitness than normal subjects. This study was planned to investigate the pulmonary function tests (PFT), respiratory muscle strength and endurance, and aerobic capacity of patients with RA, as well as the relationship of these parameters to clinical and functional status. Twenty-five RA patients aged 25-71 (48.52 +/- 14.09) and 21 control subjects aged 25-66 (45.67 +/- 13.27) participated in the study. PFT, maximum volunteer ventilation, maximum inspiratory and maximum expiratory pressures and cardiorespiratory exercise tests were carried out in all subjects to evaluate the respiratory involvement, inspiratory and expiratory muscle strength and endurance, and aerobic capacity. Patients' duration of disease, smoking and alcohol habits, duration of morning stiffness, visual analogue scale scores, ARA functional classifications and Ritchie articular indexes were recorded. All the patients and control subjects were non-exercising individuals. As a result, we found that RA patients have normal PFT but reduced respiratory muscle strength and endurance, and also reduced aerobic capacity compared to controls. According to this result, respiratory and aerobic exercises may be recommended to improve respiratory muscle strength and endurance and aerobic capacity in these patients.

Adult↗

PubMed2000

Bone mineral density and muscle strength in young men with mental retardation (with and without Down syndrome).

The objective of this study was to compare the bone mineral density (BMD) of men with Down syndrome (DS) to otherwise mentally retarded (MR) men and to investigate whether leg muscle strength of these patients is related to BMD. Two groups with MR (with and without DS) participated in the study, having met the following criteria: similar age, moderate to mild mental retardation, Tanner stage V of sexual development, similar age of beginning to walk, and equal motor activities. The DS group consisted of 8 men 23.9 +/- 4.2 years, and the MR group without DS consisted of 8 men 23.5 +/- 3.6 years. The two groups were compared with 10 sedentary students of the same age range (25.9 +/- 2.9 years) attending our University. The BMD of the 2(nd) to 4(th) lumbar vertebrae was measured in the PA projection and the mean density was expressed as g/cm(2). The isokinetic muscle strength of the right quadriceps femoris and hamstrings muscles was measured on a Cybex II isokinetic dynamometer. The value measured was peak torque at angular velocities at 60, 120, and 300 degrees.sec(-1). The results showed that BMD in DS individuals versus young adults (reference group of the scanner) was lower at the 26% level (T-score - 2.66 +/- 0.29) and significantly lower (P = 0.002) than that of the MR group. Significantly different muscle strength was observed between the DS and non-DS MR group (in quadriceps at 300 degrees.s(-1): P < 0.01, at 120 and 60 degrees. s(-1): P < 0.05; in hamstrings at 300 degrees.s(-1): P < 0.05). Higher differences in muscle strength were found between MR and control men, but no significant difference existed in BMD between them. Bivariate correlation showed that quadriceps strength significantly predicted the BMD in the DS patients. Active lifestyle and increased physical exercise to improve muscular strength should be instituted to avoid the development of osteoporosis in DS patients.

Adult↗

PubMed2003

Peripheral muscle strength training in bed-bound patients with COPD receiving mechanical ventilation: effect of electrical stimulation.

STUDY OBJECTIVE: To compare the effects of active limb mobilization (ALM) with or without electrical stimulation (ES) on muscle strength, respiratory rate (RR), heart rate, oxygen saturation, and time needed to transfer from bed to chair in two groups of patients with COPD. DESIGN: Randomized, controlled study. SETTING: Respiratory high-dependency care unit. PATIENTS: Twenty-four bed-bound patients with chronic hypercapnic respiratory failure due to COPD who were receiving mechanical ventilation, with marked peripheral muscle hypotonia and atrophy. METHODS: Patients were randomly assigned either to ALM alone or to ALM plus ES (ALM/ES). ES was applied using square-wave alternate, symmetric, and compensated impulses for 30 min bid. The duration of treatment was 28 days for all patients. RESULTS: Muscle strength improved significantly in the overall group of patients (from 1.75 +/- 0.73 to 3.44 +/- 0.65, p < 0.05). Comparing the change (end minus beginning) of the analyzed variables, ALM/ES significantly improved muscle strength (2.16 +/- 1.02 vs 1.25 +/- 0.75, p = 0.02) and RR (- 1.91 +/- 1.72 vs 0.41 +/- 1.88, p = 0.004), and decreased the number of days needed to transfer from bed to chair (10.75 +/- 2.41 days vs 14.33 +/- 2.53 days, p = 0.001). CONCLUSION: In bed-bound patients with COPD receiving mechanical ventilation, with marked peripheral muscle hypotonia and atrophy, application of ES in addition to classical ALM significantly improved muscle strength and decreased the number of days needed to transfer from bed to chair.

Aged↗

PubMed1999

Chronic eccentric exercise: improvements in muscle strength can occur with little demand for oxygen.

Eccentric contractions, the lengthening of muscle while producing force, are a common part of our everyday movements. This study presents a challenge to the accepted notion that eccentric work causes obligatory muscle injury while demonstrating that an increase in muscle strength, via eccentric work, can occur with little demand for oxygen. Nine healthy subjects, ages 18-34, were randomly placed in either an eccentric or a concentric training group. Both groups trained for 6 wk while progressively increasing training frequency and duration. Significant gains in isometric leg strength were seen in the eccentrically trained subjects only. While training, the oxygen consumption required to do the eccentric work was equal to or less than that required to do the concentric work. The results demonstrate that by progressively increasing the eccentric work rate, significant isometric strength gains can be made without muscle injury and with minimal increase in metabolic demand for oxygen. The potential clinical implications of an eccentric training program that uncouples skeletal muscle strength improvements from the demand for oxygen are alluring.

Adolescent↗

PubMed2000

Change in muscle mass and muscle strength after a hip fracture: relationship to mobility recovery.

BACKGROUND: Hip fracture in elderly persons has a serious impact on long-term physical function. This study determines the change in muscle strength and muscle mass after a hip fracture, and the associations between these changes and mobility recovery. METHODS: Ninety community-dwelling women aged 65 years and older who had recently experienced a fracture of the proximal femur were included in the study. At 2 to 10 days after hospital admission, the women's grip strength, ankle dorsiflexion strength, and regional muscle mass (by dual-energy x-ray absorptiometry) were measured, and the prefracture level of independence for five mobility function items was assessed. All measurements were repeated at 12 months. RESULTS: At follow-up, only 17.8% of the women had returned to their prefracture level of mobility function for all five items. Mobility function recovery was not related to change in skeletal muscle mass of the nonfractured leg or the arms. However, women who lost grip strength (mean loss of -28.7%, SD = 16.9%), or who lost ankle strength of the nonfractured leg (mean loss of -21.5%, SD = 14.7%), had a worse mobility recovery compared with those who gained strength (p = .04 and p = .09, respectively). In addition, chronic disease (p = .03), days hospitalized (p = .04), and self-reported hip pain (p = .07) were independent predictors of decline in mobility function. CONCLUSIONS: The results suggest that loss of muscle strength, but not loss of muscle mass, is an independent predictor of poorer mobility recovery 12 months after a hip fracture. When confirmed by other studies, these findings may have implications for rehabilitation strategies after a hip fracture.

Aged↗

PubMed1996

Muscle strength in postpolio patients: a prospective follow-up study.

Forty-three former polio patients now complaining of new progressive muscle weakness (symptomatic patients) plus 13 former polio patients without new neuromuscular complaints were included in the study. The symptomatic patients reported high frequencies of other neuromuscular complaints and a decline in their functional level. Most frequent complaints were general fatigue, low backache, and muscle pain (97.7%, 86%, and 79.1%, respectively) and a decline in the ability to walk (80%). In a prospective follow-up averaging 2.1 years, the muscle strength of 26 muscles in all four limbs of each patient was assessed by manual muscle testing and was also measured isometrically using a handheld dynamometer. During the follow-up period, we did not find a significant decrease in muscle strength in the symptomatic patients as compared to patients without new neuromuscular complaints.

Adult↗

PubMed2001

Study of differences in peripheral muscle strength of lean versus obese women: an allometric approach.

OBJECTIVE: To investigate whether peripheral muscle strength is significantly different between lean and obese women controlled for age and physical activity, using an allometric approach. DESIGN: Cross-sectional study of isometric handgrip and isokinetic leg and trunk muscle strength. SUBJECTS: 173 obese (age 39.9+/-11.4 y, body mass index (BMI) 37.8+/-5.3 kg/m(2)) and 80 lean (age 39.7+/-12.2 y, BMI 22.0+/-2.2 kg/m(2)) women. MEASUREMENTS: Anthropometric measures (weight, height) and body composition (bioelectrical impedance method), isometric handgrip (maximal voluntary contraction on the Jamar dynamometer), isokinetic trunk flexion-extension, trunk rotation, and knee flexion-extension (Cybex dynamometers). RESULTS: Absolute isokinetic strength output (that is, strength uncorrected for fat-free mass) was larger in obese compared to lean women, except for knee flexion and isometric handgrip, which were not significantly different (P>0.05). Pearson correlation coefficients between strength measures and fat-free mass (kg) were low to moderate both in lean (r=0.28-0.53, P<0.05) and in obese (r=0.29-0.49, P<0.001) women. There was no correlation with fat mass (kg) in the lean, whereas in the obese women a weak positive relation could be observed for most isokinetic data (r=0.21-0.39, P<0.01). When correcting for fat-free mass (raised to the optimal exponent determined by allometric scaling), all strength measurements were at least 6% lower in obese when compared to the lean women, except for trunk flexion, which was at least 8% stronger in obese women. DISCUSSION: The higher absolute knee extension strength measures of leg and the similar extension strength of the trunk in the obese sample compared to the lean might be explained by the training effect of weight bearing and support of a larger body mass. However when the independent effect of fat-free mass is removed, these strength measures, as well as oblique abdominal muscle and handgrip strength, turned out to be lower in obese women. These observations could be the reflection of the overall impairment of physical fitness as a consequence of obesity and its metabolic complications.

Adult↗

PubMed1980

Dialysis-induced changes in muscle strength.

Little is known about the acute effects of hemodialysis on muscle strength. Rapid changes in hemodynamic and biochemical parameters are known to occur during dialysis and may alter muscle performance. Ten patients maintained on chronic hemodialysis had measurements of quadriceps muscle and handgrip strength performed before and after dialysis. In seven of these patients maximum static inspiratory and expiratory pressures (PI max and PE max respectively) were similarly determined. Quadriceps muscle strength improved in 6 patients, decreased in 3 and remained unchanged in 1. Handgrip strength increased in 5 patients, decreased in 3, and remained unchanged in 1. PI max decreased in 6 patients and increased in 1, and PE max decreased in 4 patients and increased in 3. No significant correlation was found between the changes in strength of the tested muscle groups and the serum concentrations of sodium, potassium, calcium, phosphorus, urea nitrogen, and creatinine, changes in blood pressure of fluid balance. The dialysis-induced changes in biochemical parameters may exert opposing effects on neuromuscular performance. This may explain the diversity of the results obtained in this study.

Adult↗

PubMed2005

Decreased muscle strength and mobility of the neck in patients with rheumatoid arthritis and atlantoaxial disorders.

OBJECTIVE: To compare neck muscle strength and mobility of the cervical spine in rheumatoid arthritis (RA) patients with and without atlantoaxial (AA) disorders (anterior atlantoaxial subluxation [AAS], AA impaction). DESIGN: Clinical cross-sectional study. SETTING: Outpatient rheumatology and rehabilitation clinics in a Finnish hospital. PARTICIPANTS: Patients with RA (N=124; mean age +/- standard deviation, 62+/-12y [corrected]) on a waiting list for orthopedic surgery. Thirty (24%) patients presented with AA disorders (16 with anterior AAS, 8 with AA impaction, 6 with a combination of anterior AAS and AA impaction). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Neck function was measured by isometric neck strength and mobility tests, neck pain by a visual analog scale, erosion of the hands and feet by radiography, and the patients' function by the Health Assessment Questionnaire (HAQ). RESULTS: Maximal neck muscle strength against flexion, extension, and rotation was lower in patients with AA disorders compared with the other patients in both women (P=.012) and men (P=.017). Mobility was lowest in the AA impaction group in all measured directions (P<.001). Peripheral erosive disease was more frequent in the group with AA disorders. They also had longer disease duration and were more disabled (HAQ) than the other patients. CONCLUSIONS: Neck muscle strength is significantly decreased in patients with AA disorders. Mobility of the cervical spine is most limited in patients with AA impaction, but can be normal in cases with solitary anterior AAS.

Arthritis, Rheumatoid↗

PubMed1990

The effect of hyperinflation on respiratory muscle strength and efficiency in healthy subjects and patients with asthma.

We evaluated respiratory muscle strength and efficiency in 15 patients with asthma. There was a significant reduction in mean Plmax (89.3 +/- 4.7 versus 110.5 +/- 9.4 cm H2O, p less than 0.001) and efficiency (2.41 +/- 0.2 versus 4.2 +/- 0.6%, p less than 0.01). This reduction in strength and efficiency was seen only in the male patients. Following bronchodilator, there was a significant increase in Plmax (from 89.3 +/- 4.7 to 96.2 +/- 5.4 cm H2O, p less than 0.005) and efficiency (from 2.41 +/- 0.2 to 3.22 +/- 0.2%, p less than 0.001). There was no correlation between the change in strength and efficiency and the degree of improvement in FEV1 following bronchodilator. However, there was a significant correlation with the fall in lung volume. To determine whether hyperinflation would result in a reduction in respiratory muscle strength and efficiency, we induced a mean increase in end-expiratory lung volume of 0.66 L by applying continuous negative pressure around the chest in 10 healthy individuals. This was associated with a significant fall in Plmax (from 110.5 +/- 9.4 to 100.5 +/- 8.93 cm H2O, p less than 0.001) and efficiency (from 4.2 +/- 0.6 to 2.6 +/- 0.5%, p less than 0.005). The data suggest that the strength and efficiency of the respiratory muscles are reduced in asthmatic males but not in the females. The strength and efficiency of the respiratory muscles improve significantly following bronchodilator, and this improvement is related to reduction in lung volume.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenergic beta-Agonists↗

PubMed2001

Effects of a 12-wk resistance exercise program on skeletal muscle strength in children with burn injuries.

The posttraumatic response to burn injury leads to marked and prolonged skeletal muscle catabolism and weakness, which persist despite standard rehabilitation programs of occupational and physical therapy. We investigated whether a resistance exercise program would attenuate muscle loss and weakness that is typically found in children with thermal injury. We assessed the changes in leg muscle strength and lean body mass in severely burned children with >40% total body surface area burned. Patients were randomized to a 12-wk standard hospital rehabilitation program supplemented with an exercise training program (n = 19) or to a home-based rehabilitation program without exercise (n = 16). Leg muscle strength was assessed before and after the 12-wk rehabilitation or training program at an isokinetic speed of 150 degrees /s. Lean body mass was assessed using dual-energy X-ray absorptiometry. We found that the participation in a resistance exercise program results in a significant improvement in muscle strength, power, and lean body mass relative to a standard rehabilitation program without exercise.

Adolescent↗