Extensor Strength (extensor + strength)

Distribution by Scientific Domains

Kinds of Extensor Strength

  • knee extensor strength


  • Selected Abstracts


    A randomized clinical trial of strength training in young people with cerebral palsy

    DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 10 2003
    Karen J Dodd PhD
    This randomized clinical trial evaluated the effects of a home-based, six-week strength-training programme on lower limb strength and physical activity of 21 young people (11 females, 10 males; mean age 13 years 1 month, SD 3 years 1 month; range 8 to 18 years) with spastic diplegic cerebral palsy (CP) with independent ambulation, with or without gait aids; (Gross Motor Function Classification System levels I to III). Compared with the 10 controls, the 11 participants in the strength-training programme increased their lower limb strength (combined ankle plantarflexor and knee extensor strength as measured by a hand-held dynamometer) at 6 weeks (F(1,19)=4.58, p=0.046) and at a follow-up 12 weeks later (F(1,18)=6.25, p=0.041). At 6 weeks, trends were also evident for improved scores in Gross Motor Function Measure dimensions D and E for standing, running and jumping, and faster stair climbing. A relatively short clinically feasible home-based training programme can lead to lasting changes in the strength of key lower-limb muscles that may impact on the daily function of young people with CP. [source]


    Association Between Fitness and Changes in Body Composition and Muscle Strength

    JOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 2 2010
    George 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]


    Isokinetic Leg Muscle Strength in Older Americans and Its Relationship to a Standardized Walk Test: Data from the National Health and Nutrition Examination Survey 1999,2000

    JOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 6 2004
    Yechiam Ostchega PhD
    Objectives: To describe isokinetic knee extensor muscle strength in older U.S. men and women by age and race/ethnicity and to ascertain its relationship to a standard, timed walking-speed test. Setting: The U.S. National Health and Nutrition Examination Survey (NHANES) 1999,2000. Design: A cross-sectional nationally representative health examination survey. Participants: All surveyed persons aged 50 and older (N=1,499) who performed muscle strength and timed walk examinations in the NHANES mobile examination center. Measurements: Concentric peak torque (strength) of the knee extensors at 1.05 rads/ s,1 velocity and a 6-m walk timed in seconds. Results: Knee extensor strength was inversely associated with age (P<.01), and women had less knee extensor muscle strength than men (P<.01). After adjustment for standing height, no significant difference in muscle strength was found across the three race/ethnicity groups (Mexican Americans, non-Hispanic blacks, and non-Hispanic whites) for men or women. After adjustment for age, race/ethnicity, weight, and height, increasing knee extensor strength was associated with significant increases in meters walked per second (P<.01). Conclusion: Knee extensor muscle strength is affected by age and sex but not by race/ethnicity and it is significantly associated with timed walk. [source]


    Computed tomographic measurements of thigh muscle cross-sectional area and attenuation coefficient predict hip fracture: The health, aging, and body composition study

    JOURNAL OF BONE AND MINERAL RESEARCH, Issue 3 2010
    Thomas Lang
    Abstract Fatty infiltration of muscle, myosteatosis, increases with age and results in reduced muscle strength and function and increased fall risk. However, it is unknown if increased fatty infiltration of muscle predisposes to hip fracture. We measured the mean Hounsfield unit (HU) of the lean tissue within the midthigh muscle bundle (thigh muscle HU, an indicator of intramuscular fat), its cross-sectional area (CSA, a measure of muscle mass) by computed tomography (CT), bone mineral density (BMD) of the hip and total-body percent fat by dual X-ray absorptiometry (DXA), isokinetic leg extensor strength, and the Short Physical Performance Battery (SPPB) in 2941 white and black women and men aged 70 to 79 years. Sixty-three hip fractures were validated during 6.6 years of follow-up. Proportional hazards regression analysis was used to assess the relative risk (RR) of hip fracture across variations in thigh muscle attenuation, CSA, muscle strength, and physical function for hip fracture. In models adjusted by age, race, gender, body mass index, and percentage fat, decreased thigh muscle HU resulted in increased risk of hip fracture [RR/SD,=,1.58; 95% confidence interval (CI) 1.10,1.99], an association that continued to be significant after further adjustment for BMD. In models additionally adjusted by CSA, muscle strength, and SPPB score, decreased thigh muscle HU but none of the other muscle parameters continued to be associated with an increased risk of hip fracture (RR/SD,=,1.42; 95% CI 1.03,1.97). Decreased thigh muscle HU, a measure of fatty infiltration of muscle, is associated with increased risk of hip fracture and appears to account for the association between reduced muscle strength, physical performance, and muscle mass and risk of hip fracture. This characteristic captures a physical characteristic of muscle tissue that may have importance in hip fracture etiology. 2010 American Society for Bone and Mineral Research [source]


    Musculoskeletal Rehabilitation in Osteoporosis: A Review,

    JOURNAL OF BONE AND MINERAL RESEARCH, Issue 8 2004
    Michael Pfeifer
    Abstract Measures of musculoskeletal rehabilitation play an integral part in the management of patients with increased fracture risk because of osteoporosis or extraskeletal risk factors. This article delineates current scientific evidence concerning nonpharmacologic approaches that are used in conjunction with pharmacotherapy for prevention and management of osteoporosis. Fractures caused by osteoporotic fragility may be prevented with multidisciplinary intervention programs, including education, environmental modifications, aids, and implementation of individually tailored exercise programs, which are proved to reduce falls and fall-related injuries. In addition, strengthening of the paraspinal muscles may not only maintain BMD but also reduce the risk of vertebral fractures. Given the strong interaction between osteoporosis and falls, selection of patients for prevention of fracture should be based on bone-related factors and on risk factors for falls. Rehabilitation after vertebral fracture includes proprioceptive dynamic posture training, which decreases kyphotic posturing through recruitment of back extensors and thus reduces pain, improves mobility, and leads to a better quality of life. A newly developed orthosis increases back extensor strength and decreases body sway as a risk factor for falls and fall-related fractures. Hip fractures may be prevented by hip protectors, and exercise programs can improve strength and mobility in patients with hip fracture. So far, there is no conclusive evidence that coordinated multidisciplinary inpatient rehabilitation is more effective than conventional hospital care with no rehabilitation professionals involved for older patients with hip fracture. Further studies are needed to evaluate the effect of combined bone- and fall-directed strategies in patients with osteoporosis and an increased propensity to falls. [source]


    Cerebral Palsy: Results of Surgical Releases Augmented with Electrical Stimulation: A Case Study

    NEUROMODULATION, Issue 2 2002
    James J. McCarthy MD
    Abstract The purpose of this case study was to evaluate a patient with diplegic cerebral palsy who underwent soft tissue lengthening augmented with intramuscular electrical stimulation. This is a prospective case study, pre- and post-test design. The patient underwent soft tissue lengthenings of the lower extremities, augmented with placement of intramuscular neuromuscular electrodes. Baseline, 4-, 8-, and 12-month follow-up data were obtained which included range of motion, manual muscle strength testing, motion analysis, oxygen consumption, Gross Motor Function Measure, and Pediatric Evaluation of Disability Inventory. All measured parameters, except knee extensor strength, improved during the postoperative period (baseline to 4-month follow-up) and continued to improve during the rehabilitative period (4,12 month follow-up), despite no formal therapy or home exercise program during this period. We conclude that surgical releases augmented with electrical stimulation resulted in a satisfactory clinic outcome, and may offer a new approach to the treatment of patients with cerebral palsy. [source]