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PubMedDate not supplied

The effect of adult participation in a school-based family intervention to improve Children's diet and physical activity: the Child and Adolescent Trial for Cardiovascular Health.

UNLABELLED: BACKGROUND. There are strong theoretical reasons for including a family component with a school-based intervention aimed at eating, activity, and smoking behaviors, but the empirical findings to date are limited and show mixed results. The overall CATCH family intervention added only knowledge and attitudinal effects, but no additional behavioral outcomes. This study provides a dose analysis of the family component of the CATCH study by assessing the effect of the level of adult participation. METHOD: This secondary analysis included students who attended a CATCH family intervention school during all 3 years of the study. The extent of the adult-child interaction, the key aspect of the CATCH family intervention, was measured by the number of activity packets that an adult household member completed with the child. Multiple regression analysis was used to assess the association of adult participation with the child's knowledge, attitudes, and behaviors related to diet and physical activity. RESULTS: Statistically significant results suggested that dose effects were found for knowledge and attitudes related to diet and physical activity. These effects were more pronounced for minority and male students. CONCLUSIONS: These results suggest that dose response of a family intervention has been shown in the acquisition of positive knowledge and attitudes toward health habit changes. The methodology of dose response can be applied to other health promotion projects.

Adolescent↗
PubMed1992

Smoking, exercise, and physical fitness.

BACKGROUND: Research on smoking and physical activity provides strong evidence of smoking's negative impact and physical activity's positive impact on long-term health. However, evidence regarding the association between smoking and exercise activity and the independent effects of these factors on fitness is lacking. METHODS: The associations among exercise activity, smoking behavior, and physical fitness were examined in 3,045 Navy personnel. Exercise and smoking behaviors were measured using a lifestyle survey. Physical fitness was assessed using scores on the Navy's Physical Readiness Test. Analyses of variance were conducted to examine the relationships among smoking status, exercise activity, and PRT performance. Multiple regression procedures were used to examine the relationship between smoking and physical fitness after statistically controlling for the effects of exercise. RESULTS: Smoking was associated with lower exercise levels and lower physical endurance--both cardiorespiratory (1.5-mile run) and muscular (sit-ups). After controlling for exercise activity, smoking remained significantly associated with lower physical endurance but was not related to overall body strength (lean body mass) or percentage body fat. CONCLUSION: Smoking is a detriment to physical fitness even among relatively young, fit individuals. Study findings suggest that smokers will have lower physical endurance than nonsmokers, even after differences in the average exercise levels of smokers and nonsmokers are taken into account. Cigarette smokers should be given strong encouragement to stop smoking as part of any effort to improve physical fitness.

Adolescent↗
PubMed1994

Physical fitness of obese school children in Hat Yai, southern Thailand.

259 primary school children (average age 9.2 years) were randomly selected from three groups of children whose weights-for-height were 90-110% (normal 111), > 110-120% (over weight 25), and > 120% (obesity 123) of reference values for Bangkok children. They underwent physical fitness tests which included measurement of speed (50 meters run), flexibility (sit-reach), abdominal strength and endurance (30 seconds sit-up), vital capacity (spirometer), and indirect maximum oxygen uptake (VO2 max-submaximal bicycle ergometer). The results showed that all physical fitness tests were statistically significantly different (p < 0.05) between groups, except for flexibility in boys. But for the girls, only 50 meters run, sit-up and VO2 max showed statistically significant differences (p < 0.05). In the comparison of physical fitness tests between sexes, normal weight boys did better than girls (p < 0.05) for all tests except flexibility. There were no statistically significant differences between sexes in overweight and obese children. This study demonstrated that physical fitness of obese children was worse than that of normal children in both sexes, especially as measured by 50 meters run, sit-up and VO2 max tests. Thus, promotion of exercise in obese children should be stimulated to develop better physical fitness and weight reduction. In comparison of physical fitness between the sexes, boys had better physical fitness than girls, significant in the normal weight group only. There is no definite explanation as to why increase in weight results in no difference of physical fitness between sexes. Lifestyle, physical skills, and genetic determinants should be considered for interpretation of physical fitness.

Analysis of Variance↗
PubMed2005

Understanding interobserver agreement: the kappa statistic.

Items such as physical exam findings, radiographic interpretations, or other diagnostic tests often rely on some degree of subjective interpretation by observers. Studies that measure the agreement between two or more observers should include a statistic that takes into account the fact that observers will sometimes agree or disagree simply by chance. The kappa statistic (or kappa coefficient) is the most commonly used statistic for this purpose. A kappa of 1 indicates perfect agreement, whereas a kappa of 0 indicates agreement equivalent to chance. A limitation of kappa is that it is affected by the prevalence of the finding under observation. Methods to overcome this limitation have been described.

Family Practice↗
PubMed2006

Does body satisfaction matter? Five-year longitudinal associations between body satisfaction and health behaviors in adolescent females and males.

PURPOSE: This study addresses the question, "Does body satisfaction matter?" by examining longitudinal associations between body satisfaction and weight-related health-promoting and health-compromising behaviors five years later among adolescents. METHODS: Project EAT-II followed an ethnically and socioeconomically diverse sample of 2516 adolescents from 1999 (Time 1) to 2004 (Time 2). Associations between body satisfaction at Time 1 and health behaviors at Time 2 were examined, adjusting for sociodemographic characteristics and Time 1 health behaviors, with and without adjustment for body mass index (BMI). RESULTS: In females, lower body satisfaction predicted higher levels of dieting, unhealthy and very unhealthy weight control behaviors and binge eating, and lower levels of physical activity and fruit and vegetable intake. After adjusting for BMI, associations between body satisfaction and dieting, very unhealthy weight control behaviors, and physical activity remained statistically significant. In males, lower body satisfaction predicted higher levels of dieting, healthy, unhealthy, and very unhealthy weight control behaviors, binge eating, and smoking, and lower levels of physical activity. After adjusting for BMI, associations between body satisfaction and dieting, unhealthy weight control behavior, and binge eating remained statistically significant. CONCLUSIONS: The study findings indicate that, in general, lower body satisfaction does not serve as a motivator for engaging in healthy weight management behaviors, but rather predicts the use of behaviors that may place adolescents at risk for weight gain and poorer overall health. Interventions with adolescents should strive to enhance body satisfaction and avoid messages likely to lead to decreases in body satisfaction.

Adolescent↗
PubMed2006

Physical activity, insulin sensitivity, and hypertension among US adults: findings from the Insulin Resistance Atherosclerosis Study.

Although regular physical activity is associated with less hypertension and improved insulin sensitivity, there is debate regarding the role of insulin sensitivity in hypertension. Thus, in this cross-sectional study, the authors investigated whether physical activity and insulin sensitivity were associated with hypertension. The sample consisted of 1,599 persons aged 40-69 years who participated in the Insulin Resistance Atherosclerosis Study. The outcome measure was hypertension as measured by a standard protocol. Energy expended in vigorous physical activity was calculated from a recall interview on past-year physical activity. Descriptive statistics revealed that 590 (37%) participants had prevalent hypertension. In adjusted logistic regression analysis, participants expending >or=150 kcal/day in vigorous physical activity had an odds ratio for hypertension of 0.73 (95% confidence interval (CI): 0.55, 0.98) in comparison with participants who were sedentary. Further adjustment for insulin sensitivity resulted in attenuation of the effect of vigorous physical activity on hypertension (odds ratio = 0.97, 95% CI: 0.71, 1.33), while the effect of insulin sensitivity was significant (odds ratio = 0.33, 95% CI: 0.26, 0.41). These results suggest that longitudinal studies are warranted to determine whether insulin sensitivity is a mediator of the relation between physical activity and hypertension.

Adult↗
PubMed2004

Responsiveness of pain, disability, and physical impairment outcomes in patients with low back pain.

STUDY DESIGN: Cohort study. OBJECTIVE: To conduct a head-to-head comparison of the responsiveness of pain, disability, and physical impairment measures in patients with low back pain. SUMMARY OF BACKGROUND DATA: Pain, disability, and physical impairment measures are routinely measured in clinical practice and clinical research. However, to date, a head-to-head comparison has not been performed. METHODS: A numerical pain scale (0-10), the 24-item and 2 modified 18-item versions of the Roland Morris questionnaire, the patient specific functional scale, and physical impairment measures were completed by 155 patients with low back pain at baseline and then again after 6 weeks together with an 11-point global perceived effect scale. Responsiveness was evaluated by using effect sizes and t tests, correlating the change scores for each outcome with the global perceived effect score and by calculating the Guyatt responsiveness index. RESULTS: The most responsive outcome proved to be the patient specific functional scale (effect size = 1.6), followed by the numerical pain scale (effect size = 1.3) and 24-item Roland Morris questionnaire (effect size = 0.8). The responsiveness of the two 18-item Roland Morris versions was equal to the 24-item version. However, the physical impairment measures were not very responsive (effect size 0.1-0.6). The ranking of the responsiveness indices was consistent across all statistical analyses. CONCLUSIONS: Physical impairments are routinely measured in clinical practice and clinical research, but the lower responsiveness indicates that this approach is not optimal. Our findings suggest that more emphasis should be placed on change in pain and disability scores than on change in physical impairments.

Activities of Daily Living↗
PubMed1993

Outcome measurement in scleroderma clinical trials.

Clinical trials in scleroderma were reviewed to assess the clinimetric properties of frequently used outcome measures. Twenty-seven controlled intervention studies were found in the English literature; nine demonstrated effective therapy. The outcome measures used included skin involvement, functional status, physical performance (grip strength, oral aperture), and internal organ involvement (pulmonary, gastrointestinal, renal, and cardiac). Very few outcome measures detected between- or within-group differences even when an active drug was compared with a placebo. Skin measures were found to yield statistical differences in seven studies, patient global assessment in three, and physician global assessments in four. Internal organ measures detected differences between groups only rarely; the pulmonary diffusing capacity was statistically different twice. Physical performance measures (eg, grip strength and oral aperture) never yielded statistical differences, and in only one of five trials did a functional assessment detect statistical differences. To show drug efficacy in future trials in scleroderma, better outcome measures need to be developed and a consensus obtained on which outcomes to use so that potentially effective therapies can be tested in a standardized fashion against a placebo or current therapy. Currently, because of a lack of clinimetric data on outcome measures, therapeutic inefficacy cannot be differentiated from a lack of sensitivity in the outcome measures used. In the future, outcome measures should be chosen on the basis of the adequacy of their reliability, construct, and content validity and be sensitive to change. Ideally, outcome measures also should have criterion validity, ie, show a strong association between the measure (such as a skin score) and an irrefutable gold standard (such as skin pathology).

Clinical Trials as Topic↗
PubMed2004

Acculturation and physical activity among North Carolina Latina immigrants.

The objective of this study was to examine the association between acculturation and physical activity among first generation Latina (Hispanic women) immigrants living in North Carolina. As part of the multi-site Women's Cardiovascular Health Network, 671 first generation Latina immigrants 20-50 years of age completed in-person interviews on physical activity, acculturation (measured by a language scale, length of residence in the US, and age at arrival in the US) and other potential individual and contextual correlates of physical activity. All statistical models were adjusted for age, general health, number of children in the home, marital status, and education, with self-reported physical activity as the dependent variable. Among participants, 37.4% met recommendations for physical activity, 41.9% reported insufficient activity, and 20.7% reported no moderate or vigorous activity. Latinas with higher English language acculturation were more likely to be physically active than women with lower English language acculturation. Likewise, women who arrived to the US when they were younger than 25 years were more likely to be physically active than women who arrived when they were 25 years or older. Length of residence in the US was not associated with physical activity. These relationships persisted when restricting the sample to Mexican born women. We conclude that among first generation immigrants living in North Carolina, those with higher English language acculturation or who arrived to the US at younger ages were more likely to report being physically active. These findings suggest that future epidemiologic studies and physical activity interventions should measure and tailor programs based on English-language use and age of arrival to the US among Latina immigrants.

Acculturation↗
PubMed1991

Correlates of perceived physical appearance in children with congenital/acquired limb deficiencies.

Social support, daily hassles, marital discord, competence/adequacy, and psychological adjustment were investigated as hypothesized correlates of perceived physical appearance in 51 children with congenital or acquired limb deficiencies. Higher classmate, parent, and teacher social support were statistically predictive of higher perceived physical appearance. Higher daily hassles and marital discord were statistically predictive of lower perceived physical appearance. Higher peer acceptance, scholastic competence, and athletic competence were statistically predictive of higher perceived physical appearance. As a group, classmate, parent, and teacher social support, daily hassles, maternal and paternal perceived marital discord, peer acceptance, scholastic and athletic competence accounted for 78% of the variance in perceived physical appearance. Higher perceived physical appearance was in turn statistically predictive of lower depressive and anxious symptoms and higher general self-esteem. The findings are discussed in terms of the potentially modifiable predictors of perceived physical appearance and in terms of the role cosmetic differences play in psychological and social adaptation in children with visible physical handicaps.

Achievement↗
PubMed2002

Physics in cell biology: on the physics of biopolymers and molecular motors.

"What is Life?" is the title of a book by Erwin Schrödinger, first published in 1944. This book is a bold attempt to try to understand some of the wonders of life in terms of physics, in particular statistical mechanics. Since the publication of this visionary book, we have seen a revolution in molecular biology complemented by the development of new physical tools like single-molecule spectroscopy. The goal of this article is to highlight some examples where physics can contribute to questions in cell biology. One might hope that through interdisciplinary research one can get closer to answering Schrödinger's fundamental question.

Biophysical Phenomena↗
PubMed1990

The functional role of exercise in the development of weight and diet concerns in women.

The functional role of exercise in the development of weight preoccupation and body dissatisfaction was examined. One hundred and twelve females, identified as regular participants in exercise programmes, completed an inventory that provided information on attitudes, behaviours and psychological characteristics related to dieting and weight-control, as well as a self-report of physical activity. A structural equation model was tested that provides support for the notion that Body Mass Index, emotional reactivity and physical activity have statistically significant direct effects on weight and diet concerns, but that weight and diet concerns do not predict the degree of participation in physical activity. Significant differences in eating disorder indicators were found between sub-groups identified as 'constantly dieting' and 'rarely dieting'. The tentative, but important, conclusion was drawn that regular participation in a fitness programme may be causally related to excessive concern with weight and dieting.

Anorexia Nervosa↗
PubMed2004

Comparing the effects of physical practice and mental imagery rehearsal on learning basic surgical skills by medical students.

OBJECTIVE: The purpose of this study was to test the effects of varying the amount of physical practice and mental imagery rehearsal on learning basic surgical procedures. STUDY DESIGN: Using a sample of 65 second-year medical students, 3 randomized groups received either: (1) 3 sessions of physical practice on suturing a pig's foot; (2) 2 sessions of physical practice and 1 session of mental imagery rehearsal; or (3) 1 session of physical practice and 2 sessions of imagery rehearsal. All participants then performed a surgery on a live rabbit in the operating theater of a veterinary college under approved conditions. Analysis of variance was applied to pre- and post-treatment ratings of surgical performance. RESULTS: Physical practice followed by mental imagery rehearsal was statistically equal to additional physical practice. CONCLUSION: Initial physical practice followed by mental imagery rehearsal may be a cost-effective method of training medical students in learning basic surgical skills.

Animals↗
PubMed2005

Classical and quantum mechanics of diatomic molecules in tilted fields.

We investigate the classical and quantum mechanics of diatomic molecules in noncollinear (tilted) static electric and nonresonant linearly polarized laser fields. The classical diatomic in tilted fields is a nonintegrable system, and we study the phase space structure for physically relevant parameter regimes for the molecule KCl. While exhibiting low-energy (pendular) and high-energy (free-rotor) integrable limits, the rotor in tilted fields shows chaotic dynamics at intermediate energies, and the degree of classical chaos can be tuned by changing the tilt angle. We examine the quantum mechanics of rotors in tilted fields. Energy-level correlation diagrams are computed, and the presence of avoided crossings quantified by the study of nearest-neighbor spacing distributions as a function of energy and tilting angle. Finally, we examine the influence of classical periodic orbits on rotor wave functions. Many wave functions in the tilted field case are found to be highly nonseparable in spherical polar coordinates. Localization of wave functions in the vicinity of classical periodic orbits, both stable and unstable, is observed for many states.

Algorithms↗