Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Physics”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 451 records · Page 25Linked to original sources
PubMed1997

Measuring general levels of physical activity: preliminary evidence for the Physical Activity Questionnaire for Older Children.

This article reports three studies that investigated psychometric properties of the Physical Activity Questionnaire for Older Children (PAQ-C). The PAQ-C is a guided self-administered 7-day recall measure designed to assess general physical activity levels during the school year for children in grades four and higher. Study one, with 215 students ranging in age from 9 to 15 yr, found the PAQ-C had acceptable item and test score characteristics such as item distribution, corrected item-total correlations, and internal consistency. Study two, involving 84 students ranging from 9 to 14 yr, indicated acceptable levels of test-retest reliability for both males (r = 0.75) and females (r = 0.82) after 1 wk. The third study used Generalizability theory to investigate the reliability for using the average of either two or three PAQ-C scores collected during fall, winter, and spring seasons. Based on the responses of 200 students ranging from 8 to 16 yr, generalizability coefficients exceeded 0.80 for either the average of two or three responses for both younger (<13 yr) and older subjects. In all three studies, the PAQ-C demonstrated acceptable internal consistency and males were significantly more active than females. These results provide preliminary support for the PAQ-C as a cost efficient method of assessing general levels of children's physical activity during the school year.

Adolescent↗
PubMed1994

A comprehensive study of physical parameters, biomechanical properties, and statistical correlations of iliac crest bone wedges used in spinal fusion surgery. II. Mechanical properties and correlation with physical parameters.

Iliac crest wedges have been the most frequently used bone graft in spinal fusion procedures since the 1970s. Physical parameters and correlations among physical parameters of allogeneic iliac crest wedges have been described in part I of this series. This article discusses the mechanical properties, as well as their correlations with physical parameters, of iliac crest wedges. A total of 250 frozen-thawed, freeze-dried, and rehydrated iliac crest wedges were used in this study. The axial load-bearing capacities for wedges in the three subgroups showed no statistically significant differences, however, rehydrated wedges appeared to have the greatest load bearing capacity and compressive strength. In addition, rehydrated wedges were more deformable than either the frozen-thawed or freeze-dried wedges. Based on biomechanical properties, it is suggested that rehydrated (1 hour in vacuo), or frozen-thawed iliac crest wedge should be used in spinal fusion procedures, and the direct clinical application of nonrehydrated freeze-dried wedges should be avoided.

Aging↗
PubMed1999

Age-group differences in intrinsic motivation, goal orientations and perceptions of athletic competence, physical appearance and motivational climate in Greek physical education.

This study examined age-group differences in students' motivation, self-perceptions, task and ego orientations and perception of motivational climate in Greek physical education lessons. Six hundred and seventy-four students aged 10-17 years responded on self-reports which, in this study, had acceptable internal consistencies. The results showed that senior high school students scored lower on the scales assessing intrinsic motivation, perceived learning orientation in the lesson, task orientation and perceived athletic ability than junior high school and elementary school students. High school students had lower scores on the Perceived Physical Appearance scale and higher scores on the measure assessing perceptions of students' worries about mistakes than elementary school students. The results suggest that learning orientation should be strengthened in Greek physical education.

Achievement↗
PubMed1995

Radiology, physical science, and the emergence of medical physics.

The early development of medical physics as a separate discipline and profession is briefly reviewed. Although both x rays and radioactivity were discovered by physicists, at first the physical investigations of these phenomena, and their medical applications, proceeded along parallel but independent lines. Radiological journals were founded in Britain, Germany, and the U.S. as early as 1896-1897 but it was not until ten years later that papers on radiation physics began to appear regularly. In 1913 the first full-time physicists were appointed to posts in medical schools and hospitals: William Duane in the U.S. and Sydney Russ in Britain. Thereafter the number of physicists engaged in medical applications increased slowly but steadily, and in the 1920s they began to apply the new science of radiation dosimetry to both x ray and radium therapy. The "Hospital Physicists' Association" was founded in Britain in 1943 with 53 members and the "American Association of Physicists in Medicine" followed in 1958 with 127 charter members.

Biophysics↗
PubMed2006

Physical trauma and substance abuse: a comparative study on substance abuse in patients with physical trauma versus general population.

AIM: To evaluate the prevalence of substance abuse in a sample of patients with acute physical trauma in comparison with the general population. METHOD: Prospective study using structured interview based on DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, 4th ed) criteria for substance dependence and abuse. SETTING: Hospitals at Shiraz University of Medical Sciences, and the general population in Shiraz. PARTICIPANTS: 1,324 subjects selected randomly (324 subjects from patients with acute physical trauma, and 1,000 subjects from general population). RESULTS: The mean age was 37 (SD=15.5, age range=15-83 yr.) In the general population, the mean age was 36.5 (SD=14.29, age range=15-83). Substance use was much more prevalent among patients with acute physical trauma than in the general population. It should be mentioned that drug use precedes the trauma in the patient population and may contribute to the occurrence of trauma or disease. CONCLUSIONS: Substance use was significantly more prevalent in males than in females. Cultural attitudes toward usage of substances were found to affect the type and amount of the used substance. These findings should be considered when planning preventive and therapeutic programs.

Adolescent↗
PubMed1990

Physical features, physical attractiveness, and psychological adjustment among alcohol abuse inpatients.

Relations between specific physical features, attractiveness, and psychological adjustment of alcoholic inpatients were examined. Measures were obtained during the first week of admission and 6 weeks later (within 2 weeks of discharge). The nine physical features assessed formed three factors: face, facial expression, and body. The face factor was more strongly related to history of substance abuse than was either of the other factors. Further, the results suggested that alcoholism-related face features may be responsible for the documented relation between ratings of overall physical attractiveness and ratings of adjustment obtained at admission to a chemical dependency program; however, positive changes in body features less specifically related to a history of substance abuse (posture and grooming) are associated with counselors' ratings of improved patient adjustment over time.

Adaptation, Psychological↗
PubMed1991

Physical activity from rehabilitation to independent community function: the role of physical activity in handicapping conditions.

All ingredients are there--philosophies and principles, models and examples, competent and committed professionals, ready and willing agencies and organizations, and anxious-to-get-involved persons with handicapping conditions. The time has never been so right to go forward and onward to the heights with sport, recreation, and physical activity to produce lives worth living by persons with handicapping conditions. George Washington warned: "We ought not to look back unless it is to derive useful lessons from past errors, and for the purpose of profiting by dearly bought experience." In this case some might advise not to look back at all, because pessimists and disbelievers may be trying to overtake optimists and believers. As Henry David Thoreau stated: "If you build castles in the air, your work need not be lost; that is where they should be. Now put the foundations under them." Physical activity, recreation, and sport are important in physical, mental, emotional, and social adjustment of individuals with handicapping conditions. In many cases, active participation in such activities provides more effective and efficient rehabilitation and therapy than formal rehabilitation and therapeutic modalities and approaches. Throughout history some pioneers striving to introduce and use such techniques and approaches have been rebuffed and rejected by many facets of the medical establishment. Often, progress has come from highly committed advocates from various professional specializations with interests in activity programs for their populations. Although progress continues to be made, much greater recognition by and involvement of the medical profession are needed from the classrooms in medical schools, through all internships and residencies, to hospitals and clinics of all types, and among all medical branches and specialties.

Activities of Daily Living↗
PubMed1980

[Electronic calculation trainers for physically handicapped pupils--an example of how to use electronics in the field of individualized instruction at schools for the physically handicapped (author's transl)].

The article demonstrates, on the basis of arithmetic lessons with physically handicapped pupils, that individualised teaching methods can be considerably more effective with the aid of technology. The demand for extreme individualized instruction justified not only by psychological but also physical reasons, is attempted to be met in an important partial area, i.e., the acquisition of arithmetical skills by means of practice. Within the framework of a research project carried out on behalf of the Federal Minister of Labour, a device has been developed which takes into consideration the medical, special educational and technical viewpoints and helps to meet the practical requirements whilst taking into account the multidisciplinary problem complex. the device is an electronic trainer for mental arithmetic exercises which can be constructionally adapted to the pupil's physical deviation. It is programmed by the teacher in accordance with the different performance levels and is then a direct partner irrespective of the pupil's degree of disability.

Child↗
PubMed1994

Low body mass index, physical work capacity and physical activity levels.

In a normal population the distribution of body mass index (BMI) is such that a certain proportion of the population is likely to be at low values without necessarily being malnourished. However, although they may have low BMIs without being malnourished, they could certainly be physiologically and physically disadvantaged. An attempt is made to dissect out the probability of work capacity and physical activity being influenced by changes occurring in the human body with diminishing BMI. The conclusion reached is therefore that before physical activity is affected, the BMI would probably have to be 17 or less, although it is possible that work capacity might be reduced before this level is reached. In any case, work requiring the use of the body mass - such as carrying loads, digging or shovelling earth or coal, pulling or cycling a rickshaw, stone splitting etc.- would impose a greater stress on people of low BMI.

Adult↗
PubMed1986

Assessment methods for physical activity and physical fitness in population studies: report of a NHLBI workshop.

This report summarizes the proceedings and recommendations of a National Heart, Lung, and Blood Institute conference on assessment methods for physical activity and physical fitness in population studies held in Bethesda, Maryland, in May, 1984. Synopses of each contributor's presentation are given, as well as specific recommendations for further research. Key areas for investigation were noted as validation and standardization of questionnaires, increased use of activity monitors in exercise research, development of simpler fitness tests, and research into possible surrogate measures for fitness evaluation.

Adult↗
PubMed1985

High density lipoprotein cholesterol, habitual physical activity and physical fitness.

The relationships between habitual physical activity and fitness parameters and fasting serum high density lipoprotein cholesterol (HDL-C), total cholesterol (TC), and triglycerides (TG) were assessed in 357 men aged 30-59 years (mean 44, SD 5). A progressive submaximal power output test (PWC150), a 1-min sit-up test, and a 3-day activity energy expenditure record were obtained for each subject. HDL-C, TG, and HDL-C/TC were significantly associated with the fitness indices (PWC150 and sit-ups), but not with the mean daily energy expenditure computed from a 3-day activity record. However, when the subjects were stratified according to the maximal level of intensity reported in the work and leisure energy expenditure record, a relationship between maximal exercise or work intensity and the concentration of HDL-C and TG, and the ratio HDL-C/TC was found. When adjusted by multiple regression procedures for age, alcohol consumption, cigarette smoking, socio-economic status, fatness level, and TC, or TG, or HDL-C, as appropriate, these relationships became nonsignificant, with the exception of TG and PWC150. These results suggest that habitual physical activity of light intensities is not a major determinant of HDL-C, TC, and HDL-C/TC; it could, however, have a small but significant role in TG. In addition, data suggest that periods of exercise of higher intensity, i.e. with an energy cost of about 6 mets and more, could be a sensible mean to influence serum blood lipid levels.

Adult↗
PubMed1988

Physical fitness, physical activity, and cardiovascular disease risk factors in adolescents: the Oslo Youth Study.

Aerobic fitness, resting pulse rate, and self-reported physical activity were examined along with prevalence of cardiovascular disease risk factors in a population-based study of 413 boys and 372 girls, ages 10 to 14 years. Cardiovascular fitness (VO2 max) was predicted from heart rate measured during submaximal bicycle exercise. For both genders, fitness level was significantly and inversely related to body weight, body mass index [weight in kilos/(height in meters)2], triceps skinfold thickness, systolic and diastolic blood pressure, and pulse rate and positively related to high-density lipoprotein/total cholesterol ratio and physical activity. In addition, fitness level was positively related to high-density lipoprotein cholesterol and negatively related to triglycerides in females; it was also negatively related to height, total cholesterol, and hematocrit in males. Analyses of covariance, controlling for sexual maturity ratings, revealed that students in the lowest quartiles of VO2 max had significantly higher body mass index and triceps skinfold thickness than students in the higher quartiles. After adjustment for body mass index and sexual maturity ratings, blood pressure and pulse rate in both genders were significantly higher among students in the lower quartiles of VO2 max than among the groups who scored higher on the fitness test. Higher levels of VO2 max were also associated with a more favorable lipid profile in females. In gender-specific multiple regression analysis, triceps skinfold thickness was the strongest predictor of VO2 max, followed by pulse rate. Our study provides evidence that higher levels of fitness are associated with more favorable risk profiles in adolescents.

Adolescent↗
PubMed1990

Reliability of a modification of the health-related physical fitness test for use with physical education majors.

A modified form of the AAHPERD Health-Related Physical Fitness Test was administered to a sample of 200 college physical education majors. The skinfold measures were changed from the original test, and the flexed-arm hang was added to the test battery. The validity and reliability of the test battery has been established for middle school boys and girls. This study determined the multivariate reliability of the modified test battery using a canonical correlation model. The univariate intraclass reliabilities of the test items ranged from .91 to .99. The total redundancy for the modified test battery was .87.

Adult↗
PubMed1998

Preliminary development of a scale to measure attitudes regarding the importance of role modeling in physical activity and fitness behaviors among Health, Physical Education, Recreation, and Dance professionals.

This paper presents a new 16-item scale designed to measure attitudes regarding the importance of role modeling in physical activity and fitness behaviors among Health, Physical Education, Recreation, and Dance professionals. The measure was reviewed for face validity by a panel of experts and preliminary analyses gave as Cronbach alpha of .95 and split-half reliability of .97 for 22 graduate students.

Attitude↗
PubMed2003

Effects of a physical activity program. The study of selected physical abilities among elderly women.

This study evaluated the effects of a 12-week exercise program on the physical abilities of 55 sedentary women ages 60 to 75. The variables tested were dynamic balances, muscular endurance, sit and reach flexibility, and muscular coordination. Participants were grouped into three exercise groups (n = 45) and one control group (n = 10). Exercise was performed for 1 hour, once, twice, and three times a week for the three experimental groups. Participants were pre- and post-tested for the selected variables. Significant differences (p < .05) were found between exercise and non-exercise groups. The main effects of the training program were significant for all four variables examined, indicating that even those who participated in an exercise group once a week had a significantly higher levels of physical abilities than the control group. The improvement of the experimental groups was proportional to the frequency of the training program applied.

Activities of Daily Living↗
PubMed1976

Attitudes towards health and physical activity in the elderly. Effects of a physical training program.

Attitudes towards physical activity, perceived health, body image, anxiety and life satisfaction have been studied in men and women 60 years of age and older, volunteering for progressive endurance training. Relative to other studies of younger volunteers, the senior citizens placed more value upon activity as "an esthetic experience" and as "a means to health and fitness" showing less interest in "the pursuit of vertigo." Many non-participants and "drop-outs" perceived their current fitness as satisfactory. Subjects who selected a low frequency and low intensity of training were obese, with high Cornell Medical Index (CMI) scores on both organic and psychological scales. After 14 weeks of conditioning, 83% of subjects reported improvements in well-being. However, CMI scores were reduced on only one of twelve organic scales and none of the behavior, mood and feeling scales. Neugarten's Life Satisfaction Index, Kenyon's Body Image scales, and McPherson's the Real Me scores remained unchanged, but there was a decrease of Manifest Anxiety (Taylor scale) and a greater regard of physical activity as "the relief of tension." When subjects were classed according to changes in aerobic power, between group differences were found for "Real Me" scores and for three of Kenyon's attitude scales. Persons who trained frequently and intensively showed improvements for body image and for five of Kenyon's attitude scales.

Aged↗
PubMed2000

[Physio-pathologic aspects of aging--possible influence of physical training on physical fitness].

Two physiological parameters seem to be of major importance in maintaining physical functioning in the elderly: a capacity to perform aerobic exercises (endurance fitness) and an ability to do anaerobic work, especially maximal muscle force and power. Regular physical activity helps in maintaining these parameters at levels enabling normal functioning at everyday's living, contributing therefore to preservation of functional autonomy and independence in the elderly.

Activities of Daily Living↗
PubMed1983

Body composition, physical work capacity and physical activity habits at 18-month follow-up of middle-aged women participating in an exercise intervention program.

Thirty-six sedentary women (29-47 yr) participated in a 12-week, 4-d/week physical conditioning program (CP) involving 15-25 min/d of walking/jogging at a heart rate corresponding to 75 percent of aerobic capacity (VO2max). Twenty-three were classified obese (O, greater than 30 percent body fat, mean = 38 percent) and 13 normal (N, less than 30 percent body fat, mean = 25 percent). Significant post-CP changes included increased VO2max and decreased body fat. At 18 months post-CP a volunteer subgroup of the original 36 subjects (Ss) were re-evaluated, 19 being hydrostatically weighed, 21 exercise-tested and 28 interviewed to assess physical activity over the preceding eight quarterly periods. At CP termination 80 percent of N and 78 percent of O had intended to continue jogging, but by follow-up only 40 percent of N and 33 percent of O were so engaged, none at CP frequency, many at reduced duration and intensity. There was no significant difference between follow-up and pre-CP mean h/week of jogging for the entire follow-up group, even though eight of them (28 percent) increased their jogging over pre-CP levels. Follow-up VO2max and percent body fat means were also not significantly different from pre-CP values. It is suggested that the majority of middle-aged women participating in supervised walk-jog conditioning interventions may regress to pre-program physiologic status when left to exercise ad libitum.

Adult↗