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Exercise and muscle strength training and their effect on quality of life in patients with chronic heart failure.

BACKGROUND: There is now evidence that moderate training plays an important role in the treatment of chronic heart failure. No clear instructions exist to date as to how such training programs should be carried out. AIM: to assess the efficiency of a training program including bicycle ergometer training, moderate muscle strength training and the 6-min walk test and their influence on quality of life, anxiety and depression. METHODS AND RESULTS: Patients (67 male, 21 female) underwent a standardized 4-week training program. BASELINE DATA: LVEF=31+/-8%; LVEDD=143+/-59 ml; peak VO(2)=13.9+/-4.6 kg/ml. No adverse side effects could be observed. At discharge LVEF was 37+/-9%, (P=0.001); LVEDD=131+/-44ml (P=0.01); and peak VO(2)=15.4+/-5.0 kg/ml. Quality of life improved significantly in nearly all domains and in summary score. There were no significant changes in anxiety and depression. There is a negative correlation between the initial workload and changes in physical health (r=-0.42, P=0.001) and only a weak correlation between age and positive changes in physical health (r=0.26, P=0.05). CONCLUSIONS: A standardized training program including moderate muscle strength training could be performed safely and demonstrated improvement in clinical parameters and quality of life.

Adult↗

Magnetic resonance imaging findings of lumbar spine in the young: correlation with leisure time physical activity, spinal mobility, and trunk muscle strength in 15-year-old pupils with or without low-back pain.

From a population of 1,503 schoolchildren, 38 15-year-old children reporting recurrent or continuous low-back pain and 38 asymptomatic controls (34 boys and 42 girls) matched for age, sex, and school class were selected for tests of spinal mobility and trunk muscle strength, and for a magnetic resonance imaging (MRI) study of the lumbar spine. In addition, the subjects were asked about leisure time physical activities in an interview preceding the measurements. Spinal muscular atrophy was the only finding that was more common among physically inactive subjects (p = 0.005). Moreover, increased occurrence of disk degeneration (DD) was observed in the low-activity group. However, the difference was not significant. Neither Scheuermann-type changes nor DD were related to spinal mobility or trunk muscle strength. Children with disk protrusion were, on the average, taller (p = 0.044), and their lumbar flexion measured by flexicurve was decreased (p = 0.043). Our results strengthen further the evidence that MRI is a sensitive measure and that imaging findings must be interpreted carefully with respect to pain and physical impairment of the lumbar spine. Furthermore, no clear evidence of the association between physical activity and early DD could be found.

Abdominal Muscles↗

[Evaluation of respiratory muscle strength in patients with interstitial lung changes based on simultaneous measurement of esophageal and mouth pressure].

A well know good relation between nasal and oesophageal inspiratory pressures exists in healthy and in COPD patients "sniff manoeuvres. Similar results are obtained using "gasp" maneuvers. The aim of the study was to appreciate the usefulness of "gasp" for evaluation of inspiratory muscles strength in ILD patients. 18 ILD patients were examined: group A consisted of 9 pts (8M+IF) aged 35 +/- 8.6 yrs, with static compliance > 70% pred. (mean 98.6 +/- 16.3), group B consisted of 9 pts (6M + 3F) (aged 52 +/- 13.0) with static compliance < 70% pred. (mean 37.2 +/- 12.0), Pmo and Poe (Milic-Emili method) were measured simultaneously during breathing with Pflex device (1.7 mm diameter). Results were stored in a computer for further analysis. In all patients spirometry, plethysmography and maximal inspiratory (MIP) and maximal expiratory (MEP) pressure measurements were performed. Poe and Pmo in group A were nearly the same (8.16 +/- 1.82 vs. 8.35 +/- 2.74 kPa), but in the group B Pmo was lower than Poe (4.81 +/- 1.59 vs. 6.19 +/- 2.03 kPa; p < 0.0005). We conclude that "gasp" - Pmo is a useful method for inspiratory muscle strength measurement only in ILD patients with normal static compliance but in ILD patients with decreased compliance "gasp" - Poe measurement in necessary.

Adult↗

Lack of an association between insulin-like growth factor-I and body composition, muscle strength, physical performance or self-reported mobility among older persons with functional limitations.

OBJECTIVE: The hypothesis that decreased growth hormone (GH) secretion contributes to the functional decline that occurs with aging is far from substantiated. There have been few studies addressing the distribution and correlates of IGF-I, an indicator of GH activity, in nonclinical populations. As part of a growth hormone intervention trial, we examined the cross-sectional relations between IGF-I levels and multiple measures of physical function, body composition, and strength in a group of older men and women exhibiting mild to moderate reductions in measured physical performance. METHODS: Using a variety of advertising techniques, 155 older subjects were recruited from a metropolitan area to participate in a growth hormone and exercise intervention study. At baseline, all subjects had blood drawn for IGF-I and underwent testing of body composition using dual X-ray absorptiometry, muscle strength using isokinetic dynamometry, and functional assessment using timed performance measures and self-report. Associations between levels of IGF-I, body composition, strength, and physical function were assessed after dividing men and women separately into tertiles of IGF-I as well as treating IGF-I as a continuous variable. RESULTS: Men had higher IGF-I levels than women, and a significant inverse correlation was observed between age and IGF-I in men (r=-0.29, P=.009). There were no clear trends for associations between tertiles of IGF-I, and any of the variables tested. Linear regression models with IGF-I treated as a continuous measure were not associated significantly with any of the measures of physical function, body composition, or strength (all P > 0.05). CONCLUSIONS: In conclusion, although IGF-I levels declined with age in men, these data did not demonstrate an association between IGF-I and measures of muscle strength, body composition, or physical functioning. These findings support the growing body of evidence that IGF-I levels may not be an indicator of growth hormone activity in older persons.

Aged↗

Effects of changes in inspiratory muscle strength on the sensation of respiratory force.

The sensation of respiratory muscle force was compared in seven normal subjects before and after inspiratory muscle strength training. Subjects performed 20 sustained maximal inspiratory maneuvers daily for 6-18 wk. Maximal inspiratory pressures (MIP) increased from 124 +/- 10 to 187 +/- 9 (SE) cmH2O (P less than 0.005). Exponents of the power function relationships between mouth pressure (Pm) and the intensity of the sensation of force, corrected for inspiratory duration, during magnitude scaling of resistive and elastic ventilatory loads were the same before and after training (P greater than 0.05). However, absolute sensation intensity (S) during resistive and elastic loading was reduced significantly after strength training but returned toward baseline levels greater than or equal to 8 wk after the cessation of training when the MIP had fallen to 150 +/- 5 cmH2O. The absolute S at a given Pm during ventilatory loading changed inversely with changes in MIP (P less than 0.001). Furthermore the relationship between absolute S and Pm expressed as a proportion of the MIP (Pm/MIP) was constant over testing periods. These results suggest that the sensation of respiratory muscle force reflects the proportion of the maximum force utilized in breathing and may be based on the level of respiratory motor command signals.

Adult↗

[Evaluation of the surgical results of Achilles tendon ruptures by gait analysis and isokinetic muscle strength measurements].

OBJECTIVES: We evaluated the long-term results of surgical treatment of Achilles tendon ruptures. METHODS: Fifteen male patients (mean age 39.5 years; range 28 to 58 years) underwent surgery for Achilles tendon ruptures. All the ruptures but one occurred during sport recreation. Eleven patients were treated within the first week of trauma. After surgery, a cast was applied for four weeks, after which it was switched to a polyethylene splint that did not allow dorsiflexion. Partial weight bearing was allowed in the fourth postoperative week. Subjective and objective evaluations were made according to the system by Thermann et al. Muscle strength was measured by an isokinetic dynamometer and gait analysis was performed. Data from the healthy sides were used for comparisons. The mean follow-up was 16.8 months (range 8 to 48 months). RESULTS: Seven patients (46.7%) had no pain, while six patients (40%), one patient (6.7%), and one patient complained of pain during heavy, medium, and light sports activities, respectively. Muscle strength did not decrease in nine patients (60%). Seven patients (46.7%) returned to preinjury activity levels. Twelve patients (80%) evaluated the outcome as very good or good. The mean muscle atrophy on the affected side was 0.43 cm. The overall results were very good or good in nine patients (60%), moderate in four patients (26.7%), and poor in two patients (13.3%). One patient had superficial infection and delayed healing. Isokinetic measurements showed decreased peak torque, and increased total work. By gait analysis, no significant relationship was found between the dorsiflexion and plantar flexion difference and forefoot ground reaction forces. CONCLUSION: Early surgical treatment of Achilles tendon ruptures followed by a shorter immobilization period is associated with satisfactory results, and in the long-term, with a higher rate of patient satisfaction.

Achilles Tendon↗

[Effect of vitamin D on muscle strength and relevance in regard to osteoporosis prevention].

A successful prevention strategy for fractures in the elderly should not be limited to an improvement in bone mineral density. Equally important is the prevention of falls. Thus, 90% of fractures in the elderly are associated with a fall and 30% of all ambulatory, and 50% of institutionalized elderly age 65 years and older fall at least once a year. Fall incidence increases 10% per decade thereafter. According to recent studies, vitamin D and calcium supplementation may be a promising treatment strategy targeting both bone mineral density, as well as muscle strength and the risk of falling. The protective effect of vitamin D on fractures has been attributed to the established moderate benefit of vitamin D on bone mineral density. However, an alternative explanation might be that vitamin D affects factors directly related to muscle strength, thus, reducing fracture risk through improved function and fall prevention, in addition to its benefits on calcium homeostasis.

Accidental Falls↗

Effect of muscle strength and movement speed on the biomechanics of rising from a chair in healthy elderly and young women.

The ability to rise from a chair is an important task of daily living that is difficult for many elderly individuals to perform, and is particularly challenging when performed quickly. It is important to understand what factors limit performance of the task in older people, so that effective remedial approaches can be developed. In this study, we quantified lower-extremity muscle strength and chair-rise biomechanics in 12 young and 26 healthy elderly women during chair rise at normal and fast speeds without use of the hands. We found that hip and knee extensor torques, vertical and horizontal momentum, and vertical and horizontal ground reaction forces increased in the same way with speed for all subjects. All subjects increased their speed from normal to fast trials, but the young subjects were able to rise more quickly in the fast trials. In the normal speed trials, elderly subjects generated more trunk flexion and horizontal momentum while still in contact with the chair. Muscle activity patterns were similar for all subjects except that the elderly activated the ankle extensors earlier than the young. Although the elderly subjects were much weaker relative to body weight than the young subjects (48.5+/-14.1%), they were able to generate sufficient torques to perform the task. However, age-related differences suggest that chair-rise biomechanics were affected by the reduction in muscle strength, and that strength training regimes, particularly for the hip musculature, may be important to maintain chair-rise ability in the elderly. Copyright 1998 Elsevier Science B.V.

Journal Article↗

Transdermal testosterone gel improves sexual function, mood, muscle strength, and body composition parameters in hypogonadal men.

Testosterone (T) therapy for hypogonadal men should correct the clinical abnormalities of T deficiency, including improvement of sexual function, increase in muscle mass and strength, and decrease in fat mass, with minimal adverse effects. We have shown that administration of a new transdermal T gel formulation to hypogonadal men provided dose proportional increases in serum T levels to the normal adult male range. We now report the effects of 180 days of treatment with this 1% T gel preparation (50 or 100 mg/day, contained in 5 or 10 g gel, respectively) compared to those of a permeation-enhanced T patch (5 mg/day) on defined efficacy parameters in 227 hypogonadal men. In the T gel groups, the T dose was adjusted up or down to 75 mg/day (contained in 7.5 g gel) on day 90 if serum T concentrations were below or above the normal male range. No dose adjustment was made with the T patch group. Sexual function and mood changes were monitored by questionnaire, body composition was determined by dual energy x-ray absorptiometry, and muscle strength was measured by the one repetitive maximum technique on bench and leg press exercises. Sexual function and mood improved maximally on day 30 of treatment, without differences across groups, and showed no further improvement with continuation of treatment. Mean muscle strength in the leg press exercise increased by 11 to 13 kg in all treatment groups by 90 days and did not improve further at 180 days of treatment. Moderate increases were also observed in arm/chest muscle strength. At 90 days of treatment, lean body mass increased more in the 100 mg/day T gel group (2.74 +/- 0.28 kg; P = 0.0002) than in the 50 mg/day T gel (1.28 +/- 0.32 kg) and T patch groups (1.20 +/- 0.26 kg). Fat mass and percent fat were not significantly decreased in the T patch group, but showed decreases in the T gel groups (50 mg/day, -0.90 +/- 0.32 kg; 100 mg/day, - 1.05 +/- 0.22 kg). The increase in lean mass and the decrease in fat mass were correlated with the changes in average serum T levels attained after transdermal T replacement. These beneficial effects of T replacement were accompanied by the anticipated increases in hematocrit and hemoglobin but without significant changes in the lipid profile. The increase in mean serum prostate-specific antigen levels (within the normal range) was correlated with serum levels of T. The greatest increases were noted in the 100 mg/day T gel group. Skin irritation was reported in 5.5% of subjects treated with T gel and in 66% of subjects in the permeation-enhanced T patch group. We conclude that T gel replacement improved sexual function and mood, increased lean mass and muscle strength (principally in the legs), and decreased fat mass in hypogonadal men with less skin irritation and discontinuation compared with the recommended dose of the permeation-enhanced T patch.

Administration, Cutaneous↗

GH administration changes myosin heavy chain isoforms in skeletal muscle but does not augment muscle strength or hypertrophy, either alone or combined with resistance exercise training in healthy elderly men.

GH administration, either alone or combined with resistance exercise training (RT), has attracted interest as a means of increasing muscle mass and strength in the elderly. In the present study, 31 healthy, elderly men [age, 74 +/- 1 yr (mean +/- SEM)] were assigned to either RT [3 sessions/wk, 3-5 sets of 8-12 repetition maximum (RM)/session] + placebo (n = 8), RT + GH (n = 8), GH (n = 8), or placebo (n = 7) in a randomized, placebo-controlled, double-blinded (RT + placebo and RT + GH) or single-blinded (GH or placebo) design. Measurements of: 1) isokinetic quadriceps muscle strength; 2) quadriceps muscle power; 3) quadriceps muscle fiber type, size, and myosin heavy chain (MHC) composition; 4) quadriceps cross-sectional area (CSA) [nuclear magnetic resonance imaging (NMRI)]; 5) body composition (dual-energy x-ray absorptiometry scanning); and 6) GH-related serum markers were performed at baseline and after 12 wk. The final GH dose was 1.77 +/- 0.18 IU x d(-1) (approximately 7.2 +/- 0.8 microg x kg(-1) x d(-1)). GH alone had no effect on isokinetic quadriceps muscle strength, power, CSA, or fiber size. However, a substantial increase in MHC 2X isoform was observed with GH administration alone, and this may be regarded as a change into a more youthful MHC composition, possibly induced by the rejuvenating of systemic IGF-I levels. RT + placebo caused substantial increases in quadriceps isokinetic strength, power, and CSA; but these RT induced improvements were not further augmented by additional GH administration. In the RT + GH group, there was a significant decrease in MHC 1 and 2X isoforms, whereas MHC 2A increased. RT, therefore, seems to overrule the changes in MHC composition induced by GH administration alone. Changes in body composition confirmed previous reports of decreased fat mass, increased fat-free mass, and unchanged bone mineral content with GH administration. A high incidence of side effects was reported. Our results do not support a role for GH as a means of increasing muscle strength or mass, either alone or combined with RT, in healthy elderly men; although GH administration alone may induce changes in MHC composition.

Absorptiometry, Photon↗

Changes in hip and ankle range of motion and hip muscle strength in 8-11 year old novice female ballet dancers and controls: a 12 month follow up study.

OBJECTIVES: To evaluate in a 12 month longitudinal study changes in hip and ankle range of motion and hip muscle strength in young female novice ballet dancers. METHODS: Fifty three of the original 77 (69%) female dancers aged 8-11 years and 40 of the original 49 (82%) controls returned for follow up measurements one year later. Supine right active hip external (ER) and internal (IR) rotation were measured using an inclinometer. A turnout protractor was used to assess standing active turnout range. Range of right weight bearing ankle dorsiflexion and calf muscle length were measured in a standing lunge position using an inclinometer. A manual muscle tester was used to assess right hip flexor, IR, ER, abductor and adductor strength. RESULTS: The mean (SD) 12 month change in hip ER did not differ between dancers (11.7 (11.3)degrees) and controls (8.1 (17.6)degrees). Dancers gained 12.5 (13.5)degrees hip IR which was significantly greater than controls (0.5 (13.9)degrees). Greater IR change was associated with improved IR strength (r = 0.34, p<0.001). Dancers increased total turnout (12.0 (16.7)degrees) significantly more than controls (2.2 (20.0)degrees). There was no significant change in ankle dorsiflexion range in either group. Dancers and controls increased in all measures of hip muscle strength (p<0.001) and dancers achieved significantly greater gains in three out of five muscle groups (all, p<0.05). CONCLUSIONS: Total hip range of motion increased in both ballet students and controls at this young age. However, ankle dorsiflexion did not, which is probably due to this movement being blocked by bony apposition, rather than soft tissue stretch. This has implications for ballet teachers, as it has long been accepted that this movement could be improved with training. Dancers had greater increases in hip strength after 12 months compared with controls in muscles specific for ballet, suggesting that hip strength can be trained at this young age. Whether these gains are permanent requires further study.

Analysis of Variance↗

Relationship of muscle strength of back and upper extremity with level of physical activity in healthy women.

The objective of this study was to evaluate any correlation between the muscle strength of the upper extremity (appendicular muscles) and that of the back extensors (axial muscles) in postmenopausal women. Back extensor strength and power grip of the dominant hand were measured in 68 healthy postmenopausal women. The level of physical activity was determined according to a scale (score, 0-18) that considered vocational and avocational activities. Statistical analysis demonstrated a significant positive correlation between back extensor strength and power grip (r = 0.46, P less than 0.001) and back extensor strength and level of physical activity (r = 0.37, P less than 0.002). The correlation between level of physical activity and power grip was much less significant (r = 0.25, P less than 0.05) than that between physical activity and back strength. These data suggest that, in healthy individuals, stronger grip may also indicate stronger back extensor muscles. They also demonstrate that physical activity contributes significantly to the back extensor strength and, to a lesser degree, to the strength of the upper extremities.

Aged↗

Effects of tai chi exercise on pain, balance, muscle strength, and perceived difficulties in physical functioning in older women with osteoarthritis: a randomized clinical trial.

OBJECTIVE: Twelve forms of Sun-style tai chi exercise have been developed specifically to reduce the symptoms and improve the physical functioning of arthritic patients, and this randomized study examined the changes in symptoms and physical characteristics in older women with osteoarthritis (OA) at the completion of a 12-week tai chi exercise program. METHODS: Seventy-two patients with OA were randomly assigned into 2 groups. Due to a 41% overall dropout rate, 22 experimental subjects and 21 controls completed pre- and post-test measures over a 12 week interval. Outcome variables were physical symptoms and fitness, body mass index, cardiovascular functioning, and perceived difficulties in physical functioning. The independent t test was used to examine group differences. RESULTS: The homogeneity test confirmed that there were no significant group differences in demographic data and pretest measures. Mean comparisons of the change scores revealed that the experimental group perceived significantly less pain (t = -2.19, p = 0.034) and stiffness (t = -2.13, p = 0.039) in their joints, and reported fewer perceived difficulties in physical functioning (t = -2.81, p = 0.008), while the control group showed no change or even deterioration in physical functioning after 12 weeks. In the physical fitness test, there were significant improvements in balance (t = 3.34, p = 0.002) and abdominal muscle strength (t = 2.74, p = 0.009) for the tai chi exercise group. No significant group differences were found in flexibility and upper-body or knee muscle strength in the post-test scores. CONCLUSION: Older women with OA were able to safely perform the 12 forms of Sun-style tai chi exercise for 12 weeks, and this was effective in improving their arthritic symptoms, balance, and physical functioning. A longitudinal study with a larger sample size is now needed to confirm the potential use of tai chi exercise in arthritis management.

Accidental Falls↗

Pelvic floor muscle strength and thickness in continent and incontinent nulliparous pregnant women.

The aim of the study was to measure pelvic floor muscle function in continent and incontinent nulliparous pregnant women. The study group consisted of 103 nulliparous pregnant women at 20 weeks of pregnancy. Women reporting urinary incontinence once per week or more during the previous month were classified as incontinent. Function was measured by vaginal squeeze pressure (muscle strength) and increment in thickness of the superficial pelvic floor muscles (urogenital diaphragm) assessed by perineal ultrasound. Seventy-one women were classified as continent and 32 women as incontinent. Continent women had statistically significantly higher maximal vaginal squeeze pressure and increment in muscle thickness when compared with incontinent women. There was a strong correlation between measurements of vaginal squeeze pressure and perineal ultrasound measurements of increment in muscle thickness. This study demonstrates statistically significant differences in pelvic floor muscle function measured by strength and thickness in continent compared with incontinent nulliparous pregnant women.

Adult↗

Double-blind study of possible proximity effect of sucrose on skeletal muscle strength.

The hypotheses that close physical proximity to sucrose, without its ingestion, affects skeletal muscle strength and time between meals influences the direction of this effect, were tested. 28 college students performed 10 one-arm curls using the dominant arm, while either holding a bottle containing sucrose or sand in the free hand, without knowledge of which bottle was held. Data were first collected following an overnight fast. A week later, data were collected 1 hr. after these students had each consumed a bagel. During the fasting state, the mean maximal isometric strength while holding the bottle of sucrose was significantly greater than when holding a bottle of sand; however, no significant difference was found for the group tested after having consumed a bagel. Some possible explanations for these results are discussed, recognizing limitations imposed by lack of control for order of conditions and amount of experience.

Adolescent↗

Salbutamol, a beta 2-adrenoceptor agonist, increases skeletal muscle strength in young men.

1. beta 2-Adrenoceptor agonists have been shown to increase rapidly lean body mass and reverse muscle wasting in several animal models of human illness. However, no published information is available for humans. In the present study, we investigated the effects of a slow-release preparation of salbutamol or a placebo on skeletal muscle functional capacity in 12 healthy men. The strength of different muscle groups was measured on two occasions before and after 14 and 21 days of treatment. 2. No significant changes in muscle strength were observed with placebo during the trial. In contrast, the strength of both quadriceps muscles increased significantly (12 +/- 3%) after 14 days on salbutamol, and remained elevated at 21 days. Whereas the strength of the hamstring muscles of the dominant leg significantly increased after 21 days on salbutamol (22 +/- 6%), the strength of the non-dominant hamstring muscles returned to baseline values. 3. There was no significant change in the grip strength of either hand in these subjects during the trial. The maximal static inspiratory mouth pressure increased significantly (7 +/- 2%) after 14 days on salbutamol, and increased further after 21 days (15 +/- 4%); the expiratory mouth pressure remained constant. No significant changes in body weight, skinfold thickness, lean body mass or limb circumferences were measured in either group. 4. These data demonstrate that short-term administration of salbutamol increases voluntary muscle strength in man. However, the magnitude and duration of this effect vary between muscle groups. This study implies that the beta 2-adrenoceptor agonists may be of therapeutic potential in altering skeletal muscle function in humans.

Adult↗