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Extension Strength (extension + strength)
Kinds of Extension Strength Selected AbstractsAssociation Between Fitness and Changes in Body Composition and Muscle StrengthJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 2 2010George A. Kuchel, [see editorial comments by Drs. Gustavo Duque, pp 37 OBJECTIVES: To examine the association between physical fitness, assessed according to ability and time to complete a 400-m walk, on changes in body composition and muscle strength over a 7-year period. DESIGN: Prospective observational cohort study. SETTING: Memphis, Tennessee, and Pittsburgh, Pennsylvania. PARTICIPANTS: Two thousand nine hundred forty-nine black and white men and women aged 70 to 79 participating in the Health, Aging and Body Composition Study. MEASUREMENTS: Body composition (fat and bone-free lean mass) was assessed using dual-energy X-ray absorptiometry in Years 1 to 6 and 8. Knee extension strength was measured using isokinetic dynamometry and grip strength using isometric dynamometry in Years 1, 2, 4, 6, and 8. RESULTS: Less fit people weighed more and had a higher total percentage of fat and a lower total percentage of lean mass than very fit men and women at baseline (P<.001). Additionally, the least fit lost significantly more weight, fat mass, and lean mass over time than the very fit (all P<.01). Very fit people had the highest grip strength and knee extensor strength at baseline and follow-up; decline in muscle strength was similar in every fitness group. CONCLUSION: Low fitness in old age was associated with greater weight loss and loss of lean mass than with high fitness. Despite having lower muscle strength, the rate of decline in the least fit persons was similar to that in the most fit. In clinical practice, a long-distance walk test as a measure of fitness might be useful to identify people at risk for these adverse health outcomes. [source] Do Muscle Mass, Muscle Density, Strength, and Physical Function Similarly Influence Risk of Hospitalization in Older Adults?JOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 8 2009Peggy Mannen Cawthon PhD OBJECTIVES: To examine the association between strength, function, lean mass, muscle density, and risk of hospitalization. DESIGN: Prospective cohort study. SETTING: Two U.S. clinical centers. PARTICIPANTS: Adults aged 70 to 80 (N=3,011) from the Health, Aging and Body Composition Study. MEASUREMENTS: Measurements were of grip strength, knee extension strength, lean mass, walking speed, and chair stand pace. Thigh computed tomography scans assessed muscle area and density (a proxy for muscle fat infiltration). Hospitalizations were confirmed by local review of medical records. Negative binomial regression models estimated incident rate ratios (IRRs) of hospitalization for race- and sex-specific quartiles of each muscle and function parameter separately. Multivariate models adjusted for age, body mass index, health status, and coexisting medical conditions. RESULTS: During an average 4.7 years of follow-up, 1,678 (55.7%) participants experienced one or more hospitalizations. Participants in the lowest quartile of muscle density were more likely to be subsequently hospitalized (multivariate IRR=1.47, 95% confidence interval (CI)=1.24,1.73) than those in the highest quartile. Similarly, participants with the weakest grip strength were at greater risk of hospitalization (multivariate IRR=1.52, 95% CI=1.30,1.78, Q1 vs. Q4). Comparable results were seen for knee strength, walking pace, and chair stands pace. Lean mass and muscle area were not associated with risk of hospitalization. CONCLUSION: Weak strength, poor function, and low muscle density, but not muscle size or lean mass, were associated with greater risk of hospitalization. Interventions to reduce the disease burden associated with sarcopenia should focus on increasing muscle strength and improving physical function rather than simply increasing lean mass. [source] Performance-Based Measures of Physical Function for High-Function PopulationsJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 5 2006J. David Curb MD OBJECTIVES: To improve and broaden the applicability of performance-based measures of function for use in clinical and research settings. DESIGN: Cross-sectional repeated-measures study. SETTING: Research clinic. PARTICIPANTS: Population-based sample of Japanese Americans without significant functional impairments aged 35 to 55 and 56 to 71 (N=203). MEASUREMENTS: Performance-based measures of physical function, including range of standard tests, newer automated measures of balance and strength and data on cognitive function, lifestyle, medical history, and physical activity. RESULTS: Of the nonplatform balance measures, only the one-leg stand was reliable (reliability coefficient (rc) =0.69) and able to discriminate between functional levels. Combining the Fourth National Health and Nutrition Examination Survey protocol of folded arm position while standing on a foam pad with the more-sophisticated balance platform test had the highest reliability and discrimination. With the strength chair, high rcs (0.88,0.96) were found for upper and lower extremity tests. Timed chair stands, a test of lower extremity and central strength were reliable. The 6-minute walk had a high rc (0.90). CONCLUSION: Many performance tests used today are not reliable. Only a few discriminate between the most highly functioning individuals and individuals with good function. Thus, a new recommended battery includes unassisted single-leg stand, balance platform "foam pad, eyes closed," elbow flexion and knee extension strength (strength chair), grip strength, timed chair stands, and the 6-minute walk. These simple performance-based tests have good reliability and discrimination across the range of function and can be used in most clinical and research settings to quickly assess global functional level. [source] Effect of 8-Month Vertical Whole Body Vibration on Bone, Muscle Performance, and Body Balance: A Randomized Controlled Study,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 5 2003Saila Torvinen MD Abstract Recent animal studies have given evidence that vibration loading may be an efficient and safe way to improve mass and mechanical competence of bone, thus providing great potential for preventing and treating osteoporosis. Randomized controlled trials on the safety and efficacy of the vibration on human skeleton are, however, lacking. This randomized controlled intervention trial was designed to assess the effects of an 8-month whole body vibration intervention on bone, muscular performance, and body balance in young and healthy adults. Fifty-six volunteers (21 men and 35 women; age, 19-38 years) were randomly assigned to the vibration group or control group. The vibration intervention consisted of an 8-month whole body vibration (4 min/day, 3-5 times per week). During the 4-minute vibration program, the platform oscillated in an ascending order from 25 to 45 Hz, corresponding to estimated maximum vertical accelerations from 2g to 8g. Mass, structure, and estimated strength of bone at the distal tibia and tibial shaft were assessed by peripheral quantitative computed tomography (pQCT) at baseline and at 8 months. Bone mineral content was measured at the lumbar spine, femoral neck, trochanter, calcaneus, and distal radius using DXA at baseline and after the 8-month intervention. Serum markers of bone turnover were determined at baseline and 3, 6, and 8 months. Five performance tests (vertical jump, isometric extension strength of the lower extremities, grip strength, shuttle run, and postural sway) were performed at baseline and after the 8-month intervention. The 8-month vibration intervention succeeded well and was safe to perform but had no effect on mass, structure, or estimated strength of bone at any skeletal site. Serum markers of bone turnover did not change during the vibration intervention. However, at 8 months, a 7.8% net benefit in the vertical jump height was observed in the vibration group (95% CI, 2.8-13.1%; p = 0.003). On the other performance and balance tests, the vibration intervention had no effect. In conclusion, the studied whole body vibration program had no effect on bones of young, healthy adults, but instead, increased vertical jump height. Future human studies are needed before clinical recommendations for vibration exercise. [source] Randomized double-blind placebo-controlled crossover study of caffeine in patients with intermittent claudication,BRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 10 2010A. H. Momsen Background: Intermittent claudication is a disabling symptom of peripheral arterial disease for which few medical treatments are available. This study investigated the effect of caffeine on physical capacity in patients with intermittent claudication. Methods: This randomized double-blind placebo-controlled crossover study included 88 patients recruited by surgeons from outpatient clinics. The participants abstained from caffeine for 48 h before each test and then received either a placebo or oral caffeine (6 mg/kg). After 75 min, pain-free and maximal walking distance on a treadmill, perceived pain, reaction times, postural stability, maximal isometric knee extension strength, submaximal knee extension endurance and cognitive function were measured. The analysis was by intention to treat. Results: Caffeine increased the pain-free walking distance by 20·0 (95 per cent confidence interval 3·7 to 38·8) per cent (P = 0·014), maximal walking distance by 26·6 (12·1 to 43·0) per cent (P < 0·001), muscle strength by 9·8 (3·0 to 17·0) per cent (P = 0·005) and endurance by 21·4 (1·2 to 45·7) per cent (P = 0·004). However, postural stability was reduced significantly, by 22·1 (11·7 to 33·4) per cent with eyes open (P < 0·001) and by 21·8 (7·6 to 37·8) per cent with eyes closed (P = 0·002). Neither reaction time nor cognition was affected. Conclusion: In patients with moderate intermittent claudication, caffeine increased walking distance, maximal strength and endurance, but affected balance adversely. Registration number: NCT00388128 (http://www.clinicaltrials.gov). Copyright © 2010 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd. [source] Physical performance limitations among adult survivors of childhood brain tumorsCANCER, Issue 12 2010Kirsten K. Ness PhD Abstract BACKGROUND: Young adult survivors of childhood brain tumors (BTs) may have late effects that compromise physical performance and everyday task participation. The objective of this study was to evaluate muscle strength, fitness, physical performance, and task participation among adult survivors of childhood BTs. METHODS: In-home evaluations and interviews were conducted for 156 participants (54% men). Results on measures of muscle strength, fitness, physical performance, and participation were compared between BT survivors and members of a population-based comparison group by using chi-square statistics and 2-sample t tests. Associations between late effects and physical performance and between physical performance and participation were evaluated in regression models. RESULTS: The median age of BT survivors was 22 years (range, 18-58 years) at the time of the current evaluation, and they had survived for a median of 14.7 years (range, 6.5-45.9 years) postdiagnosis. Survivors had lower estimates of grip strength (women, 24.7 ± 9.2 kg vs 31.5 ± 5.8 kg; men, 39.0 ± 12.2 kg vs 53.0 ± 10.1 kg), knee extension strength (women, 246.6 ± 95.5 Newtons [N] vs 331.5 ± 5.8 N; men, 304.7 ± 116.4 N vs 466.6 ± 92.1 N), and peak oxygen uptake (women, 25.1 ± 8.8 mL/kg per minute vs 31.3 ± 5.1 mL/kg per minute; men, 24.6 ± 9.5 mL/kg per minute vs 33.2 ± 3.4 mL/kg per minute) than members of the population-based comparison group. Physical performance was lower among survivors and was associated with not living independently (odds ratio [OR], 5.0; 95% confidence interval [CI], 2.0-12.2) and not attending college (OR, 2.3; 95% CI 1.2-4.4). CONCLUSIONS: Muscle strength and fitness values among BT survivors were similar to those among individuals aged ,60 years and were associated with physical performance limitations. Physical performance limitations were associated with poor outcomes in home and school environments. The current data indicated an opportunity for interventions targeted at improving long-term physical function in this survivor population. Cancer 2010. © 2010 American Cancer Society. [source] | ||||||||||