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At least 199 records · Page 11Linked to original sources

PubMed2001

Angiotensin-converting enzyme inhibitor therapy improves respiratory muscle strength in patients with heart failure.

STUDY OBJECTIVES: Respiratory muscle strength has been shown to be reduced in patients with chronic heart failure. The purpose of this prospective study was to determine whether long-term therapy with the angiotensin-converting enzyme (ACE) inhibitor perindopril improves respiratory muscle strength in patients with chronic heart failure. PATIENTS AND METHODS: Eighteen patients with stable chronic heart failure were administered perindopril, 4 mg/d, in addition to their standard therapy for a period of 6 months. Fourteen patients completed the study. Maximum inspiratory pressure (PImax) and maximum expiratory pressure (PEmax) expressed in percentage of predicted values, left ventricular ejection fraction (LVEF) determined by means of two-dimensional echocardiography, and pulmonary volumes were obtained before and after therapy. MEASUREMENTS AND RESULTS: As compared to baseline, there was a significant increase in both PImax and PEmax after therapy (57 +/- 27% predicted vs 78 +/- 36% predicted and 62 +/- 20% predicted vs 73 +/- 15% predicted, respectively; each p < 0.05). LVEF increased (34 +/- 5% vs 41 +/- 10%; p < 0.05); functional class improved by > or = 1 New York Heart Association (NYHA) class in five patients. There were no changes in pulmonary volumes. No correlation was found between changes in PImax and PEmax and changes in either LVEF or NYHA functional class. CONCLUSIONS: In patients with chronic heart failure, long-term therapy with the ACE inhibitor perindopril improved respiratory muscle strength, as indicated by significant increases in PImax and PEmax.

Angiotensin-Converting Enzyme Inhibitors↗

PubMed2003

Dynamics of muscle strength improvement during isokinetic rehabilitation of athletes with ACL rupture and chondromalacia patellae.

AIM: To assess quantitatively dynamics and extent of the increase in muscle strength during isokinetic rehabilitation. METHODS EXPERIMENTAL DESIGN: daily measurements of muscle strength; detailed testing at the beginning and at the end of rehabilitation. SETTING: Cybex Rehabilitation Center, Zagreb. SUBJECTS: 44 athletes (31 m, 13 F, age 16-35), 3 injury-defined groups: athletes with ACL rupture (non-reconstructed and reconstructed) and chondromalacia patellae. INTERVENTIONS: all subjects underwent isokinetic rehabilitation on Cybex Orthotron KT2 device, using individually designed protocols (extension and flexion exercises, concentric muscle contractions, 15 treatments). MEASUREMENTS: monitoring of daily progress on rehabilitation device and detailed testing on diagnostic device. RESULTS: All patients showed considerable improvement. Muscle strength improved on average 141% (SD=110) in ACL-reconstructed group, 144% (SD=130) for chondromalacia patellae group and 150% (SD=74) for ACL-non-reconstructed group, comparing to initial strength. Dynamic status tested on Cybex Otrhotron diagnostic device prior and after rehabilitation strongly correlated with final progress monitored on the rehabilitation device. CONCLUSION: Isokinetic rehabilitation is a quick and effective method in treating knee injuries in athletes. Both types of objective criteria have shown significant increase in muscle strength. The improvement of muscle strength was on the average 149% (SD=101), which is about 10% daily for 15 treatments. The greatest progress, 19% per day, occurred during first five days. The athletes were able to resume their sport activities as follows: patients from chondromalacia patellae group, and most of them from the non-reconstructed ACL group were back in competition within a month, while 75% from the ACL reconstructed group came back within 3 months, and the rest of them within 5 months.

Adolescent↗

PubMed2006

Creatine supplementation improves muscle strength in patients with congestive heart failure.

BACKGROUND: Both, cardiac and skeletal muscle creatine levels are depressed in patients with congestive heart failure (CHF). Oral supplementation of creatine (Cr) could increase physical performance in healthy volunteers. We therefore hypothesized that oral creatine supplementation improves skeletal muscle strength, quality of live and symptom-limited performance in patients with CHF. METHODS: In a double-blind, placebo-controlled and crossover-designed study, 20 patients suffering from congestive heart failure more than 6 months and a peak oxygen uptake (peak VO2) below 20 ml/min/kg received 4 x 5 g Cr daily vs. placebo for 6 weeks and were crossed over for the following 6 weeks. Peak VO2, VO2 at the anaerobic threshold (VO2AT), ejection fraction (EF), distance in 6-minute-walk-test (6 min W), and muscle strength (Modified Sphygmomanometer (MS)) were determined at baseline, after 6, and after 12 weeks. Dyspnoea after 6-minute-walk-test was measured using the Borg Scale. Quality of live was assessed with the Minnesota Living with Heart Failure Questionnaire (MLHFQ). RESULTS: 13 of 20 Patients finished the study. After 6 weeks of creatine supplementation there was a significant increase in body weight and muscle strength compared to baseline and placebo (p < 0.05). However, there was no significant change in peak VO2, VO2AT, walking distance, quality of life assessment and EF. CONCLUSION: Short-term creatine supplementation inaddition to standard medication in patients with CHF leads to an increase in body weight and an improvement of muscle strength. This effect is restricted to the time of supplementation.

Aged↗

PubMed2005

Similarities in skeletal muscle strength and exercise capacity between renal transplant and hemodialysis patients.

Exercise intolerance is common in hemodialysis (HD) and renal transplant (RTx) patients. Aim of the study was to assess to what extent exercise capacity and skeletal muscle strength of RTx patients differ from HD patients and healthy controls and to elucidate potential determinants of exercise capacity in RTx patients. Exercise capacity, muscle strength, lean body mass (LBM) and physical activity level (PAL) were measured by cycle-ergometry, isokinetic dynamometry, DEXA and Baecke Questionnaire, respectively, in 35 RTx, 16 HD and 21 controls. VO2peak and muscle strength of the RTx patients were significantly lower compared to controls (p<0.01), but not different compared to HD patients. In RTx patients, strength (p<0.001), PAL (p=0.001) and age (p=0.045) were significant predictors of VO2peak. Muscle strength was related to LBM (p=0.001) and age (p=0.001), whereas gender (p<0.001) and renal function (p=0.01) turned out to be significant predictors of LBM. No effects of corticosteroids were observed. Exercise capacity and muscle strength seem equally reduced in RTx and HD patients compared to controls. In RTx patients, muscle strength and PAL are highly related to exercise capacity. Renal function appears to be a significant predictor of LBM, and through the LBM, of muscle strength and exercise capacity.

Exercise Test↗

PubMed1999

Disability, physical activity, and muscle strength in older women: the Women's Health and Aging Study.

OBJECTIVE: To study associations of motor disability, physical activity, and muscle strength in older women, in particular to investigate whether model of spiraling decrease is expressed in the data. DESIGN: Cross-sectional analysis using data from the baseline measurements of The Women's Health and Aging Study (WHAS). SETTING: Participants' homes. PARTICIPANTS: A total of 1,002 disabled women aged 65 years and older living in the community. OUTCOME MEASURES: Motor disability was measured by the number of self-reported difficulties in grasping, lifting 101b, walking across a small room, walking 1/4 mile, climbing 10 steps, and doing heavy housework. Level of physical activity was determined from response to a series of questions on the frequency and amount of common activities and physical exercise. Hand grip and knee extension forces were measured using portable hand-held dynamometers. RESULTS: Disability and physical activity were inversely associated, with inactivity being most common among the most disabled women. Those with poorer strength reported more difficulties in motor activities. Greater strength was found among the physically more active. In stratified analyses, the positive association of physical activity on knee extension strength was consistent across disability levels. Multiple regression analysis showed that both physical activity and muscle strength were significant predictors for severity of disability. Structural equation model (LISREL) showed that muscle strength had a mediating role between physical activity and disability; disability was associated with physical inactivity, which correlated with lower muscle strength, which was associated with greater degree of disability. CONCLUSION: Even though causality cannot be confirmed in this cross-sectional analysis, our findings suggested a spiraling model of decline in which muscle strength has a significant role.

Activities of Daily Living↗

PubMed1983

Effect of increased abdominal muscle strength on forced vital capacity and forced expiratory volume.

The purpose of this study was to investigate the effect of increased abdominal muscle strength on forced vital capacity (FVC) and forced expiratory volume in one second (FEV1). Twenty-five healthy volunteers were assigned randomly to either an experimental group (n = 16) or a control group (n = 9). Peak isokinetic torque of the abdominal muscles during the performance of a trunk curl-up, FVC, and FEV1 were measured before and after a 12-session training program designed to increase abdominal muscle strength. The control group did not train. Although abdominal muscle strength increased significantly after the training program, FVC and FEV1 did not increase significantly. The correlations between abdominal muscle strength and FVC, and between abdominal muscle strength and FEV1 were low. Based on these results, abdominal muscle strengthening does not appear to be an effective means of improving FVC and FEV1 in healthy subjects.

Abdominal Muscles↗

PubMed2000

Relationship between muscle strength and vitamin D metabolites: are there therapeutic possibilities in the elderly?

To test the hypothesis that muscle weakness associated with aging is in part due to low serum levels of vitamin D, we investigated the relationship between muscle strength and serum levels of vitamin D metabolites in ambulatory elderly people who were not receiving vitamin D supplementation. We enrolled 319 ambulatory elderly subjects (103 women: mean age 74.2, age range 65-86; 216 men: mean age 76.6, age range 66-95) between April and August 1995. The study design was cross-sectional. Muscle strength was measured as leg extension power in watts (LEP). Mean 25-hydroxyvitamin D serum concentrations were higher in male participants at 36.2 ng/ml (range 3.0-85.0) versus 27.4 ng/ml (range 5.0-88.0) in female subjects (p = 0.008). We found 12 percent of female and 18 percent of male subjects with 25-hydroxyvitamin D values below the lower threshold (< 12 ng/ml). Mean 1,25-dihydroxyvitamin D levels were similar in both sexes: 39.8 pg/ml (range 15.0-73.0) in women and 37.9 pg/ml (range 13.0-69.0) in men. LEP declined with age in women and men (f: r = -0.35, p = 0.001; m: r = -0.48, p < 0.0001). Men were significantly stronger than women (p < 0.0001). In men both 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D showed pairwise correlation with LEP (r = 0.24; p = 0.0004/r = 0.14; p = 0.045). In women only 1,25-hydroxyvitamin D was significantly correlated with LEP (r = 0.22; p = 0.03). In ANCOVA, including all participants, explaining LEP by sex (p < 0.0001), age (p < 0.0001), BMI (p = 0.013), 1,25-dihydroxyvitamin D (p = 0.02), 25-hydroxyvitamin D (p = 0.18) and iPTH (p = 0.82), all factors showed significant effects except 25-hydoxyvitamin D and iPTH (r2 of the whole model: 0.41). In conclusion our results support the view that, in concert with other factors, deficiency of both 25-hydroxyvitamin D and 1,25-hydroxyvitamin D contributes to the age-related decline in muscle strength. Modest, but significant relationships between 1,25-dihydroxyvitamin D and muscle strength in both sexes, and 25-hydroxyvitamin D in male participants could be documented. Whether the impact of vitamin D on calcium homeostasis and bone mineral density or directly on the muscle tissue level is more important for prevention of hip fractures remains unclear. Further prospective and comparative treatment studies should be performed, in order to evaluate whether and in which dose requirements, vitamin D supplementation can improve muscle strength in the elderly.

Aged↗

PubMed1995

Ventilatory muscle strength and endurance in myasthenia gravis.

Patients with generalized myasthenia gravis (MG) often have associated ventilatory muscle involvement. It is not known whether patients with isolated ocular muscle involvement have identifiable involvement of their ventilatory muscles. Most studies have assessed muscle involvement by measuring muscle strength; however, we hypothesized that measures of ventilatory muscle endurance may be more sensitive tests of ventilatory muscle involvement in myasthenia gravis. We studied 17 patients with myasthenia gravis (four with ocular involvement alone and 13 with varying degrees of generalized myasthenia gravis). Spirometry, ventilatory muscle strength (maximum inspiratory and expiratory pressures (MIP and MEP)) and endurance (2 min incremental threshold loading test) were measured before and 20 min after i.m. neostigmine. We compared the results with those of 10 normal controls. We found no difference between patients with isolated ocular involvement and controls. Ocular myasthenia gravis patients did not improve after neostigmine. The patients with generalized myasthenia gravis had reduced baseline ventilatory muscle strength (MIP 67 cmH2O (70% of predicted), MEP 86 cmH2O (50% of pred) and endurance (mean maximal load achieved = 246 g, mean pressure at highest load (P) = 19.4 cmH2O) compared with controls. After neostigmine, there was a significant increase in MIP in patients with generalized myasthenia gravis and a trend towards an increased MEP. As a group, the patients with generalized myasthenia gravis did not demonstrate a change in their ventilatory muscle endurance after neostigmine; however, there was considerable interpatient variability in response. We conclude that patients with isolated ocular MG have normal ventilatory muscle strength when tested conventionally.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed2007

Measuring muscle strength for people with chronic obstructive pulmonary disease: retest reliability of hand-held dynamometry.

OBJECTIVE: To evaluate the retest reliability and quantify the degree of measurement error when measuring isometric muscle strength with a hand-held dynamometer for people with chronic obstructive pulmonary disease (COPD). DESIGN: Retest reliability of hand-held dynamometry for 4 muscle groups was assessed on 2 occasions separated by a 2-week interval. SETTING: Community rehabilitation center. PARTICIPANTS: Eight men and 4 women (mean age +/- standard deviation, 71.4+/-10.3y) with moderately severe COPD (percentage of predicted forced expiratory volume in 1 second, 41.5%+/-17.7%). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Muscle strength (in kilograms). Statistical analysis was conducted by calculating intraclass correlation coefficients and 95% confidence intervals for both group and individual scores. RESULTS: All reliability coefficients were greater than .79. Muscle strength would need to increase by between 4% and 18% in groups of people with COPD and between 34% and 58% in a person with COPD to be 95% confident of detecting real changes. CONCLUSIONS: Hand-held dynamometry is suitable for monitoring change in muscle strength and testing hypotheses for groups of people with COPD. However, hand-held dynamometry is not likely to detect changes in muscle strength for a person with COPD.

Aged↗

PubMed2006

Androgen treatment and muscle strength in elderly men: A meta-analysis.

OBJECTIVES: To review published, randomized trials examining the effect of androgen treatment on muscle strength in older men. DESIGN: Systematic review using meta-analysis procedures. SETTING: Computerized and manual searches. PARTICIPANTS: MEDLINE, EMBASE, CINAHL, and the Cochrane Register were searched for trials. Key words included testosterone, androgen, sarcopenia, muscle loss, aged, aging, elderly, older, geriatric, randomized controlled trials, and controlled clinical trials. Sixty-five nonoverlapping studies were found. Meta-analysis methods were used to evaluate the 11 randomized, double-blind trials. INTERVENTION: Testosterone or dihydrotestosterone (DHT) replacement therapy in healthy men aged 65 and older. MEASUREMENTS: Tests of muscle strength. RESULTS: The studies included 38 statistical comparisons. The mean g-index (g(i)) adjusted for sample size was 0.53 (95% confidence interval (CI) = 0.21-0.86). Subanalyses revealed larger effects for measures of lower extremity muscle strength (g(i) = 0.63, 95% CI = 0.03-1.28) than for upper extremity muscle strength (g(i) = 0.47, 95% CI = 0.12-0.84). A larger mean g-index was found for injected (g(i) = 0.95, 95% CI = 0.33-1.58) than topical (g(i) = 0.26, 95% CI = 0.08-0.42) or oral (g(i) = -0.21, 95% CI = -1.40-1.02) administration of testosterone/DHT. Effect sizes were related to study characteristics such as subject attrition and design-quality ratings. Sensitivity analyses revealed that the elimination of one study reduced the mean g-index from 0.53 to 0.23. CONCLUSION: The results suggest that testosterone/DHT therapy produced a moderate increase in muscle strength in men participating in 11 randomized trials. One study influenced the mean effect size.

Aged↗

PubMedDate not supplied

Comparison of abdominal muscle strength in post-parous and nil parous subjects.

This study investigated the relationship between parity and abdominal muscle strength using the Kraus-Weber test. Female volunteers (700) comprising 350 post-parous and 350 nil-parous subjects participated in the study. Physical characteristics of the subjects (age, body weight, height and ponderal index) were measured while the abdominal muscle strength was assessed using three of the six-item Kraus-Weber tests. Results were analysed using descriptive and inferential statistics. Independent t-test showed a significant difference in values of the abdominal. muscle strength of the post-parous and nil-parous subjects (P < 0.05). Pearson's correlation's matrix showed an inverse relationship between parity and scores on the Kraus-Weber test in the post-parous subjects. A significant difference was observed across the parity groups in age, Ponderal index and scores on the Kraus-Weber tests. It was concluded that the abdominal muscle strength of the post-parous subjects was low compared to nil-parous subjects. Due to the ease of application and its non-dependence on the use of sophisticated equipment, it was recommended that the Kraus-Weber test should be used for both subjective assessment and training of abdominal muscle strengths.

Abdominal Muscles↗

PubMed2002

Multiaxis muscle strength in ACL deficient and reconstructed knees: compensatory mechanism.

PURPOSE: It is unclear how muscle strength in tibial rotation and knee abduction change following anterior cruciate ligament (ACL) injury and reconstruction. Such strength changes are likely, considering the oblique orientation of the ACL and the constraint provided by the ACL at various tibial rotation and adduction positions. The purposes of this study were to evaluate multiaxis muscle strength in ACL deficient and reconstructed knees and to gain insights into potential compensatory mechanisms adopted by the patients. METHODS: Muscle strength in tibial internal-external rotation, abduction-adduction, and flexion-extension were investigated in 19 chronic ACL deficient, 18 acute ACL deficient, 21 ACL reconstructed, and 23 normal subjects. The strength ratios of flexion/extension, abduction/adduction, and internal/external rotation were determined for each subject and compared across the different populations. RESULTS: The chronic ACL deficient patients showed significantly lower strength ratio in internal/external rotation than that of the normal controls and acute ACL deficient subjects (P = 0.02), indicating a compensatory mechanism developed by the patients to unload the ACL and/or to avoid unstable knee positions. For ACL reconstructed patients, the internal/external rotation strength ratio became closer to their counterparts in normal controls than that of chronic ACL deficient patients, presumably reflecting the reduced need for compensation after reconstruction. Furthermore, compared with strength reduction in knee extension, reductions in tibial rotation and abduction strength following ACL reconstruction were less severe and more easy to recover. CONCLUSION: A better understanding of changes in multiaxis muscle strength and the associated compensatory mechanism will help us evaluate treatment outcome more accurately and develop more effective treatment modalities with focus on muscles that help protect and unload the ACL.

Adaptation, Physiological↗

PubMed1997

Quality of life, body composition and muscle strength in adult growth hormone deficiency: the influence of growth hormone replacement therapy for up to 3 years.

OBJECTIVE: Adults with GH deficiency complain frequently of low energy levels, emotional lability and mental fatigue resulting in a low perceived quality of life (QOL). Body composition is altered with increased fat mass and decreased lean body mass and muscle strength is reduced. The aims of this study were to determine the effects of replacement GH treatment on: (a) body composition and muscle strength and (b) QOL, using specifically selected and adapted measures. DESIGN: A 12-month study (double-blind placebo-controlled for the first 6 months and open for the second 6 months) of GH replacement injections (0.125 iu/kg/week for the first month and 0.25 iu/kg/week for the following 5 months of each study period) in GH deficient adults on QOL, body composition and muscle strength. This was followed by an open study of a further 12 months' GH treatment assessing QOL and muscle strength. Finally, QOL was assessed after up to 3 years of GH replacement treatment. PATIENTS: Thirty of the 32 adult patients with GH deficiency enrolled completed the initial 12-month study (10 male, mean age 33.5 years, mean (SD) stimulated serum GH response 3.0 mU/l (2.86)). Nineteen patients then opted to continue GH treatment. Of these, 13 patients were available for assessment after a further 12 months' and 24 months' treatment. MEASUREMENTS: Health-related QOL was assessed using 2 specifically adapted scales for adults with GH deficiency: the Life Fulfillment Scale and the Impact Scale. In addition 4 other self-rating questionnaires were used: Nottingham Health Profile, Hospital Anxiety and Depression Scale, Self Esteem Scale and Mental Fatigue Scale. Body composition was assessed by DEXA and quadriceps muscle strength by measuring maximum voluntary contractions. RESULTS: In the initial 12 months' placebo-controlled study perceived energy levels increased after 6 and 12 months of GH treatment (P < 0.01 compared with baseline) in the patients receiving GH for the full 12-month period. There were no changes in energy levels throughout the study in the group receiving placebo for the first 6 months. Also small improvements in impact scores were found after 6 months of GH treatment (P < 0.05) but this was not sustained at 12 months. In both GH and placebo groups life fulfillment worsened after 6 months, but then improved to baseline values after 12 months. In the patients who persisted with GH replacement, energy levels continued to improve (at 2 years, P < 0.01 compared with baseline) but then fell (at 3 years, P = NS compared with baseline). A similar pattern was observed in emotional reaction scores. However, improvements in self-esteem were maintained (at 3 years, P < 0.05 compared with baseline). Body composition altered favourably over the initial 12-month study period with a significant increase in lean mass and decrease in fat mass in both groups after 6-12 months of GH. There were no changes in muscle strength in either group during the initial 12-month study. However, in the patients who were available for assessment after a further 12 months of GH treatment, muscle strength increased significantly (P < 0.02 compared with baseline). CONCLUSION: GH replacement treatment for 6-12 months leads to significant improvements in body composition (DEXA) but longer-term treatment may be needed to increase muscle strength. Self-esteem scores improve and are maintained after 3 years of treatment. Energy levels and emotional reaction improve during treatment for up to 2 years but decline thereafter.

Adult↗

PubMed1995

Decreased isokinetic trunk muscle strength and performance in long-term survivors of childhood malignancies: correlation with hormonal defects.

OBJECTIVE: To evaluate trunk muscle strength and performance in long-term survivors of childhood malignancies relative to age and sex-matched controls, and to relate the muscle strength observations to the therapeutic agents used and possible hormonal disturbances. DESIGN: Age and sex-matched cohort study. SETTING: Referral center in the northern part of Finland. PATIENTS: Forty-six long-term survivors of childhood cancer. Mean age at examination 19.1 years and median off-therapy time 9.4 years. INTERVENTION: Isokinetic dynamometer testing. MAIN OUTCOME MEASURES: Measurements of trunk muscle peak torque (PT) and total work done (TWD) were performed at angle speeds of 50 degrees/sec and 200 degrees/sec. The results were normalized relative to body fat-free weight (FFW). RESULTS: PT in the trunk muscles was lower in the patients at both angle speeds (mean normalized PT = 5.7Nm/kgFFW vs 7.6Nm/kgFFW for controls at 50 degrees/sec), as also was TWD except for extension TWD at the higher angle speed (mean normalized TWD = 59.9J/kgFFW vs 84.6J/kgFFW for controls at 200 degrees/sec). The normalized PT at 50 degrees/sec and TWD at 200 degrees/sec were lower in the males with testicular damage; also, low age at diagnosis correlated positively with muscle strength and performance. There were no differences in normalized PTs or TWDs between cranial radiation and non-radiation cases, or between growth-hormone-deficient and non-deficient cases, and the patients without cranial radiation or with normal growth hormone secretion still had lower normalized PTs and TWDs than the controls. CONCLUSIONS: Survivors of childhood malignancies have decreased maximal trunk muscle strength and performance. The etiology of this effect remains unclear, but young age at diagnosis, as well as serum testosterone levels in male survivors, evidently influence muscle strength and performance.

Adolescent↗

PubMed1993

Body composition and muscle strength in healthy men receiving testosterone enanthate for contraception.

To determine the effect of androgens on body composition and muscle strength, we measured fat-free mass (kg), fat mass (kg), and bone density (g/cm2) by dual x-ray absorptiometry, and muscle strength (Newton meters) by dynamometry in a controlled, prospective study involving 13 nonathletic men receiving testosterone enanthate 200 mg/week in for 6 months and 8 healthy controls. Biochemical markers of bone turnover were measured in the treated subjects at baseline and 6 months. In the treated subjects at 6 months, fat-free mass (mean +/- SEM) increased by 9.6 +/- 1.0% (P < or = 0.01) whereas fat mass decreased by 16.2 +/- 6.7% (P < or = 0.05). Changes in muscle strength ranged from -1.6-19.2%. Only hip adduction increased 19.2 +/- 9.5% (P < 0.05). Changes in bone density ranged from -1.3-5.2%, decreasing significantly at one site and increasing significantly at four of the nine sites measured (P < 0.05). Serum testosterone increased by 91.1 +/- 7.5% (P < 0.01), and testicular volume decreased by 24.0 +/- 3.2% (P < 0.01). Serum osteocalcin increased by 35.7 +/- 17.3% (P < 0.05), serum immunoreactive PTH (iPTH) increased by 41.4 +/- 15.1% (P < 0.05), serum calcium decreased by 2.3 +/- 1.0% (P < 0.05), and serum albumin decreased by 4.5 +/- 1.7% (P < 0.05). There were no detectable changes in fat-free mass, fat mass, muscle strength, or bone density in controls. The administration of testosterone enanthate in pharmacological doses for 6 months resulted in a modest reduction in fat mass and small increases in fat-free mass, muscle strength, and bone density. These changes do not support the use of androgens for enhancing athletic performance.

Absorptiometry, Photon↗

PubMed2005

The course of functional status and muscle strength in patients with late-onset sequelae of poliomyelitis: a systematic review.

OBJECTIVES: To review systematically studies of late-onset polio sequelae on the course of functional status and muscle strength over time and to identify prognostic factors of change. DATA SOURCES: We conducted a computerized literature search up to July 2004 in MEDLINE, EMBASE, CINAHL, Web of Science, PsychInfo, and the Cochrane controlled trial register using the key words: postpolio, postpoliomyelitis, postpoliomyelitis syndrome, post poliomyelitis muscular atrophy, and poliomyelitis. STUDY SELECTION: Reports were selected by 1 reviewer if the study involved subjects with a history of poliomyelitis, the outcome measures described functional status or muscle strength, and follow-up was for at least 6 months. DATA EXTRACTION: Studies were summarized with regard to population, design, sample size, outcome measures, results, and methodologic scores. Overlap in populations between studies was checked. DATA SYNTHESIS: Of 71 potentially relevant studies, 19 were included (2 on functional status, 15 on muscle strength, 2 on both muscle strength and functional status). Two studies on the course of functional status had sufficient quality and reported inconsistent results. Four studies on the course of muscle strength had sufficient quality. Two studies reported a decline in strength and 2 reported no change. Decline in strength was only reported in studies with a follow-up period longer than 2 years. One study reported extent of paresis as a prognostic factor for change in perceived physical mobility. CONCLUSIONS: Conclusions cannot be drawn from the literature with regard to the functional course or prognostic factors in late-onset polio sequelae. The rate of decline in muscle strength is slow, and prognostic factors have not yet been identified. Long-term follow-up studies with unselected study populations and age-matched controls are needed, with specific focus on prognostic factors.

Activities of Daily Living↗

PubMed2005

Supervised exercise training improves aerobic capacity and muscle strength in older women with heart failure.

BACKGROUND: The effect that supervised or unsupervised exercise training has on aerobic capacity (peak oxygen consumption [VO2peak]), muscle strength and quality of life in older women with heart failure remains unknown. OBJECTIVE: To examine the effect of six months (three months supervised followed by three months unsupervised) of aerobic training (AT) or combined aerobic and strength training (CAST) on VO2peak, muscle strength and quality of life in older women with heart failure. METHODS: Twenty older women (mean age +/- SD, 72+/-8 years) with clinically stable heart failure were randomly assigned to AT (n=10) or CAST (n=10). Supervised AT was performed two days per week at 60% to 70% heart rate reserve, whereas unsupervised training was performed two days per week at a rate of perceived exertion of 12 to 14 on the Borg scale. The CAST group also performed one to two sets of low-to-moderate intensity strength training two days per week. RESULTS: Supervised AT or CAST resulted in an increase in VO2peak (12%; P<0.05) and leg press strength (13%; P<0.05) that returned to baseline after unsupervised training. Vertical row strength was greater (+23%; P<0.05) after supervised CAST and remained unchanged after supervised or unsupervised AT. Supervised or unsupervised exercise training was not associated with a significant change in quality of life. CONCLUSIONS: Supervised AT or CAST are effective modes of exercise to improve VO2peak and muscle strength in older women with heart failure. However, the improvements in VO2peak and muscle strength are not maintained with unsupervised exercise training.

Age Factors↗

PubMed2001

Isokinetic measurement of trunk muscle strength in women with chronic low-back pain.

OBJECTIVES: To investigate the relationships among chronic low-back pain and obesity, total spinal range of motion, and trunk muscle strength. The short-term impact of trunk muscle strengthening exercises on this condition was also examined. DESIGN: A controlled, prospective study of trunk muscle strengths of patients with chronic low-back pain and the short-term impact of exercise on strength. The study group consisted of 25 female patients who had been experiencing low-back pain for at least 3 mo, and the control group included 20 age-matched women without known low-back trouble. The Davenport Index was used to calculate the body mass indexes of all subjects. The Oswestry Disability Questionnaire was used to assess pain in the study group. Full flexion and extension ranges of motion were measured, then isokinetic measurements of trunk muscles were performed at 60-, 120-, and 180-degrees/sec velocities. Isometric measurements were also recorded for both flexors and extensors at a 60-degree angle. RESULTS: Increased body mass index and decreased trunk muscle strength were found to be directly associated with chronic low-back pain (P < 0.05). After a 15-day standard trunk strengthening exercise program in the patient group, trunk muscle strength was found to be increased (P < 0.05). CONCLUSIONS: Obesity and decrease in trunk muscle strength are important factors in chronic low-back pain, and a trunk muscle strengthening program will be helpful in reducing the pain.

Abdominal Muscles↗