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Strength Measures (strength + measure)
Selected AbstractsScaling and Testing Multiplicative Combinations in the Expectancy,Value Model of AttitudesJOURNAL OF APPLIED SOCIAL PSYCHOLOGY, Issue 9 2008Icek Ajzen This article examines the multiplicative combination of belief strength by outcome evaluation in the expectancy,value model of attitudes. Because linear transformation of a belief strength measure results in a nonlinear transformation of its product with outcome evaluation, use of unipolar or bipolar scoring must be empirically justified. Also, the claim that the Belief × Evaluation product fails to explain significant variance in attitudes is found to be baseless. In regression analyses, the main effect of belief strength takes account of the outcome's valence, and the main effect of outcome evaluation incorporates the outcome's perceived likelihood. Simulated data showed that multiplication adds substantially to the prediction of attitudes only when belief and evaluation measures cover the full range of potential scores. [source] Moisture sorption in moulded fibre trays and effect on static compression strengthPACKAGING TECHNOLOGY AND SCIENCE, Issue 4 2003Gitte Sørensen Abstract This study provides a basic understanding of moisture sorption in moulded fibre packaging for food at varying environmental temperatures and humidities, and the resultant effects on static compression strength. The Guggenheim,Anderson,de Boer (GAB) model is used successfully to construct moisture sorption isotherms in the range 2,25°C and 33,98% relative humidity (% r.h.) (R2 = 0.949,0.999), in which moisture content varies from 5.4 to 28.3,g/100,g dry fibre. Static compression strength (SCS) is substantially affected by changes in moisture content of moulded fibre and decreases exponentially with increasing moisture content. The results indicate a minor hysteresis effect on static compression strength. For adsorption of moisture, a relative strength measure, % SCS (experimental SCS in kg divided by a standard SCS in kg), is given by % SCS = 13.83 + 166.50,·,e,0.0978,m (m is moisture content). The temperature dependence of moisture adsorption is incorporated in the GAB model by relating GAB coefficients, m0 and C, exponentially to temperature, T. By combining this with the exponential model for % SCS, static compression strength can be predicted directly from the surrounding temperature and humidity. Illustrated in a response surface plot the effects of changes in the surroundings are simple and readily accessible, e.g. for packaging designers and sales people. It is noted that an increase in humidity from 50% r.h. to 95% r.h. at constant temperature results in a drastic reduction in % SCS from 100% to 40%, whereas the temperature effect is typically less than 10% SCS when reducing temperature from 25°C to 2°C. Copyright © 2003 John Wiley & Sons, Ltd. [source] Angiotensin-Converting Enzyme Genotype Affects the Response of Human Skeletal Muscle to Functional OverloadEXPERIMENTAL PHYSIOLOGY, Issue 5 2000Jonathan Folland The response to strength training varies widely between individuals and is considerably influenced by genetic variables, which until now, have remained unidentified. The deletion (D), rather than the insertion (I), variant of the human angiotensin-converting enzyme (ACE) genotype is an important factor in the hypertrophic response of cardiac muscle to exercise and could also be involved in skeletal muscle hypertrophy , an important factor in the response to functional overload. Subjects were 33 healthy male volunteers with no experience of strength training. We examined the effect of ACE genotype upon changes in strength of quadriceps muscles in response to 9 weeks of specific strength training (isometric or dynamic). There was a significant interaction between ACE genotype and isometric training with greater strength gains shown by subjects with the D allele (mean ± S.E.M.: II, 9.0 ± 1.7%; ID, 17.6 ± 2.2%; DD, 14.9 ± 1.3%, ANOVA, P 0.05). A consistent genotype and training interaction (ID DD II) was observed across all of the strength measures, and both types of training. ACE genotype is the first genetic factor to be identified in the response of skeletal muscle to strength training. The association of the ACE I/D polymorphism with the responses of cardiac and skeletal muscle to functional overload indicates that they may share a common mechanism. These findings suggest a novel mechanism, involving the renin-angiotensin system, in the response of skeletal muscle to functional overload and may have implications for the management of conditions such as muscle wasting disorders, prolonged bed rest, ageing and rehabilitation, where muscle weakness may limit function. [source] The Relationship Between Lower Body Strength and Obstructed Gait in Community-Dwelling Older AdultsJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 3 2002Ecosse L. Lamoureux PhD OBJECTIVES: To determine the relationship between lower body strength of community-dwelling older adults and the time to negotiate obstructed gait tasks. DESIGN: A correlational study. SETTING: The Biomechanics Laboratory, Deakin University, Australia. PARTICIPANTS: Twenty-nine women and 16 men aged 62 to 88 were recruited using advertisements placed in local newspapers. The participants were independent community dwellers, healthy and functionally mobile. MEASUREMENTS: Maximal isometric strength of the knee extensors and dynamic strength of the hip extensors, hip flexors, hip adductors, hip abductors, knee extensors, knee flexors, and ankle plantar flexors were assessed. The times to negotiate four obstructed gait tasks at three progressively challenging levels on an obstacle course and to complete the course were recorded. The relationship between strength and the crossing times was explored using linear regression models. RESULTS: Significant associations between the seven strength measures and the times to negotiate each gait task and to walk the entire course at each level were obtained (r = ,0.38 to ,0.55; P < .05). In addition, the percentage of the variance explained by strength (R2), consistently increased as a function of the progressively challenging level. This increase was particularly marked for the stepping over task (R2 = 19.3%, 25.0%, and 27.2%, for levels 1, 2, and 3, respectively) and the raised surface condition (R2 = 17.1%, 21.1%, and 30.8%, for levels 1, 2, and 3, respectively). CONCLUSION: The findings of the study showed that strength is a critical requirement for obstructed locomotion. That the magnitude of the association increased as a function of the challenging levels suggests that intervention programs aimed at improving strength would potentially be effective in helping community-dwelling older adults negotiate environmental gait challenges. J Am Geriatr Soc 50:468,473, 2002. [source] Reliability of quantifying foot and ankle muscle strength in very young childrenMUSCLE AND NERVE, Issue 5 2008Kristy J. Rose MHSc Abstract Preschool-age children with neuromuscular disorders are often excluded from clinical trials due to the lack of reliable and objective strength measures. We evaluated the reliability of measuring foot and ankle muscle strength in 60 healthy children age 2,4 years. The strength of foot inversion and eversion, ankle plantarflexion, and dorsiflexion was measured using a hand-held dynamometer. Intrarater and interrater reliability of two assessors was determined for each muscle group using intraclass correlation coefficients (ICCs), 95% confidence intervals (CIs), and standard error of measurement (SEM). For all muscle groups intrarater (ICC2,2 = 0.85-0.94, 95% CI = 0.75,0.96, SEM = 1.5,4.7 N) and interrater (ICC2,1 = 0.88,0.96, 95% CI = 0.81,0.98, SEM = 1.2,4.6 N) reliability was high for all children. As expected, reliability was generally highest in 3- and 4-year-old children and lowest in 2-year-old children. Hand-held dynamometry can reliably measure foot and ankle strength in very young children and may help aid in diagnosis and in characterizing disease progression in disorders affecting the foot and ankle. Muscle Nerve, 2008 [source] Validity and normative data for thirty-second chair stand test in elderly community-dwelling Hong Kong ChineseAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 3 2006D.J. Macfarlane It is important to establish valid field measures of lower body strength in the elderly, and to provide representative normative values that are culturally specific in order to help health professionals in the risk assessment of this group. A sample of 1,038 elderly Hong Kong Chinese undertook a 30-sec chair stand test (30CST), with a subsample of 143 completing isometric measures of maximal hip flexion and knee extension, plus a habitual physical activity questionnaire. The 30CST was significantly, yet only weakly, correlated with the isometric strength measures (r , 0.3,0.4), but accurately discriminated between levels of habitual physical activity and across ages in decades. The normative values generated provide useful data for health screening in this elderly Hong Kong population, but do not compare well with their healthier US counterparts. Am. J. Hum. Biol. 18:418,421, 2006. © 2006 Wiley-Liss, Inc. [source] | |||||||||||||