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PubMed1992

Physical activity, physical fitness and mortality in a sample of middle aged men followed-up 25 years.

One-thousand-seven-hundred-twelve men aged 40-59, representing two demographic samples of rural areas in Northern and Central Italy, were examined in 1960 and then followed-up for 25 years. Total mortality and coronary mortality were related to the entry measurements of physical activity at work, estimated in three levels by a simple questionnaire and to four possible indicators of physical fitness, ie resting heart rate, the circumference of the right arm cleaned from the contribution of skin and subcutaneous fat, vital capacity and forced expiratory volume in 3/4 sec, the latter two adjusted by height. The four indicators of fitness and the score of physical activity were somewhat related each other in the expected direction. Both all causes and coronary mortality were indirectly related to the score of physical activity. The relative risk for age adjusted rates of sedentary vs heavy workers was 1.23 for all causes of death, and 1.72 for coronary deaths. Direct univariate relationships were found between resting heart rate and mortality (for both all causes and coronary deaths) whereas indirect relationships were found for arm circumference and the two indicators of respiratory function. The age adjusted relative risks between the upper and the bottom quartile of the distribution were, for all causes of death, 0.75 for vital capacity, 0.68 for forced expiratory volume 1.32 for heart rate, and 0.84 for arm circumference. The correspondent relative risks for coronary deaths were 0.71, 0.65, 1.23 and 1.02 respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed2004

Attitudes of physical therapist students toward physical therapist assistants before and after full-time clinical internships.

Development of attitudes of physical therapists (PTs) toward physical therapist assistants (PTAs) begins during their professional education, and attitudes are influenced further by clinical experiences. The purpose of this study was to understand attitudes of student PTs toward PTAs. We surveyed 66 clinical intern students enrolled in an entry-level master of physical therapy program. PT students received the same survey before and after their full-time clinical internship. Eleven Likert scale items were used to assess students' attitudes toward PTAs in the areas of competence, financial remuneration, and job security. One item was designed to determine whether PT students' level of contact with PTAs influenced attitudes. A random sample of 13 (20.9%) students who returned surveys were asked to participate in a telephone interview designed to enrich the quantitative data. After item analysis, five of the scale items were eliminated from the analyses due to poor internal consistency. Cronbach's alpha of the remaining six scale items was 0.75. Survey results reveal that PT students maintain an overall positive attitude toward PTAs before and after full-time clinical internship. Qualitative interview data support this finding. Students' attitudes in specific areas of PTA competence were negative and positive, however. The negative attitude may have been based on the students' beliefs that PTAs are not competent to perform physical therapy in situations that are changing or unpredictable. Positive attitudes may have been reflective of the students' beliefs that PTAs are competent to implement established plans of care. Student ranking of four professional issues showed a significant difference before and after full-time clinical internships.

Adult↗
PubMed2004

Decision making for physical therapy service delivery in schools: a nationwide survey of pediatric physical therapists.

BACKGROUND AND PURPOSE: A nationwide survey was conducted to explore decision making among school-based physical therapists and to examine recommendations regarding the models, contexts, frequency, and intensity of physical therapy service delivery. Factors that the therapists considered important in making clinical decisions also were examined. SUBJECTS AND METHODS: A survey instrument using a clinical case format was sent to all members of the American Physical Therapy Association's Section on Pediatrics who identified themselves as school-based therapists (N=1,154); 626 respondents, from all 50 states, completed the survey. Four case descriptions were presented in the survey: 2 preschool girls with developmental delay (1 with and 1 without cognitive impairment) and a boy with cerebral palsy (at 6 and 12 years of age). RESULTS: Individual direct services were recommended by 52% to 55% of the respondents for both 4-year-old girls and for the boy at 12 years of age; 92% of the respondents recommended them for the boy at 6 years of age. The most prevalent choice (48%-73%) for the context of service delivery (location or environment) was a combination of integrated and isolated contexts. For those respondents who selected direct services (individual or group, or both), the mean recommended monthly frequency for the boy at 6 years of age (5.8) was more than twice that for the boy at 12 years of age (2.4). The mean suggested direct frequency for the girl with cognitive impairment (4.5) was greater than that for the girl without cognitive impairment (4). The students' functional levels were considered very to extremely important in decision making by 87% to 90% of the respondents. DISCUSSION AND CONCLUSION: Survey responses were relatively consistent with current literature regarding school practice and principles of motor learning. Recommendations varied for each case, regarding the models, contexts, frequency, and intensity of physical therapy service delivery.

Adult↗
PubMed1995

Epidemiology of physical activity, physical fitness and coronary heart disease.

Observational population-based studies have consistently shown an inverse dose-response gradient between physical activity or fitness and coronary heart disease. This relationship is more firmly established in men. Existing studies suggest that the physical activity gradient, and perhaps the fitness gradient, is produced by a combination of varying levels of both the intensity and the amount of habitual physical activity. It is not at present possible to definitively describe the dose-response association between the intensity of physical activity and the risk of coronary heart disease. An answer to this important question awaits further research.

Coronary Disease↗
PubMed1998

The assessment of physical activity in individuals and populations: why try to be more precise about how physical activity is assessed?

Simple epidemiological measures of physical activity have proved sufficient to demonstrate associations with many chronic disease outcomes, but they have infrequently separated physical activity into its different dimensions, nor have they allowed estimation of dose-response effects. Generating greater clarity about the nature of the exposure-disease relationship, is an important step in the development of an appropriate public health intervention. This clarity can only be achieved with reliable and valid measurement instruments, which objectively and quantitatively assess the dimension of physical activity that is of interest for a particular health outcome. Objective techniques, such as heart rate monitoring, which have been directly compared to gold standard assessment methods, may be of use in medium-sized epidemiological studies and as a validation tool for questionnaires to be used in larger studies. The combination of methods with uncorrelated error, would result in an improved estimation of the true exposure and is an important area for research. Improved assessment would be of use in aetiological studies, in tracking trends in physical activity within populations, making objective comparisons between populations and in monitoring the effect of interventions.

Adult↗
PubMed1979

The effect of a four-month physical fitness program on a young and an old group matched for physical fitness.

A young (X = 36.8 years) and an old (X = 52.9 years) group (n = 12) matched for physical fitness performed a graded exercise test at the beginning and after a 4-month physical fitness program consisting of calisthenics, jogging, and recreational activities. The purpose of the study was to determine if there were any differences in response to physical training in the two age groups of similar fitness. Sixteen physiological and four biochemical variables were measured. There was no significant difference in VO2 max between the young and old groups. Also, there were no significant differences between groups for serum total lipids, cholesterol, triglycerides, or glucose levels. The effects of the training program were similar for both the young and old groups.

Adult↗
PubMed2001

High-intensity aerobic training during a 10 week one-hour physical education cycle: effects on physical fitness of adolescents aged 11 to 16.

The aim of this study was to analyse the effects of a high-intensity aerobic training program on different components of physical fitness in adolescents aged 11 to 16 years. The subjects were divided into a high intensity (HI) group (243 girls and 260 boys) and a control (C) group (21 girls and 27 boys). HI and C completed a weekly 3 hour physical education (PE) session. Before and after a 10-week period, the two groups performed the European physical fitness test battery (EUROFIT). During these 10 weeks HI spent one hour out of three at a specific PE session. These specific sessions consisted of short intermittent exercises (10 seconds) at 100 to 120% of maximal aerobic speed. They showed a significant influence on standing broad jump (2.9 %, P<0.05, F=4.85), 20 meter shuttle run (3.8%, p0.001, F=23.21) and on the maximal distance covered over 7 min (7.6 %, P< 0.001, F= 14.48). For C there was no improvement in EUROFIT performances. It was concluded that training at high intensity improves not only children's aerobic fitness but also performance of standing broad jump. Well-monitored, adequate intensive training is necessary for a more desirable functional development.

Adolescent↗
PubMed1979

Effects of physical training and cardiorespiratory physical fitness on exercise-heat tolerance: recent observations.

Most authors agree that physical training in a cool environment improves tolerance to exercise in the heat and the rate of heat acclimatization, but the extent or degree of improvement remains controversial. The best improvement in heat tolerance for men is associated with intensive interval or continuous training at a training intensity greater than 50% of maximal oxygen uptake (Vo2max) for 8-12 weeks; the Vo2max should be increased 15-20%. Far less is known about the appropriate type, intensity and duration of endurance training associated with improved exercise-heat tolerance in women. The major benefits of physical training appear to apply to both short term (less than 2 hrs) or long term (greater than 2 hrs) exercise-heat exposures for men. Generally, individuals with high Vo2max values (previously trained and endurance athletes) are at an advantage in the heat. Utilization of proper physical training appears to produce about 50% of the total adjustment resulting from heat acclimatization, while increased fitness is associated with greater retention of acclimatization in cool environments. Female athletes appear somewhat better able to tolerate exercise in hot environments than nonathletic females while differences between highly trained females and males do not appear as dramatic as once thought.

Acclimatization↗
PubMed2000

Heparin, low molecular weight heparin and physical methods for preventing deep vein thrombosis and pulmonary embolism following surgery for hip fractures.

BACKGROUND: Hip fracture patients have a high risk of thromboembolic complications following surgical management. OBJECTIVES: To examine the effects of heparin (unfractionated (U), and low molecular weight (LMW) heparins), and physical methods (compression stockings, calf or foot pumps) for prevention of deep venous thrombosis (DVT) and pulmonary embolism after surgery for hip fracture in the elderly. SEARCH STRATEGY: We searched the Cochrane Musculoskeletal Injuries Group trials register, Medline, Embase, and reference lists of published papers and books. We contacted trialists and other workers in the field. Date of most recent search: September 1996. SELECTION CRITERIA: Randomised and quasi-randomised trials evaluating the use of heparins and physical agents for prevention of DVT and pulmonary embolism in patients undergoing surgery for hip fracture. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed methodological quality and extracted data. Trials were grouped into four categories (heparin versus control, mechanical versus control, LMW heparin versus U heparin, and miscellaneous) and results pooled where possible. MAIN RESULTS: The 26 included trials involved 2600 predominantly female and elderly patients. Overall, trial quality was disappointing. Ten trials involving 826 patients which compared U heparin with control, and four trials of 471 patients which compared LMW heparin with control, showed a reduction in the incidence of lower limb DVT (121/511 (24%) versus 203/519 (39%); Peto odds ratio 0.41; 95% confidence interval 0.31 to 0.55). There were insufficient data to confirm the efficacy of either agent in the prevention of pulmonary embolism. There was a non significant increase in overall mortality in the heparin group (46/420 (11%) versus 35/423 (8%); Peto odds ratio 1.39; 95% confidence interval 0. 86 to 2.23). Data were inadequate for all other outcomes including wound complications. There is insufficient evidence from five trials, involving 644 patients, to establish if LMW heparin was superior to U heparin. Most trials evaluating heparins had methodological defects. Four trials, involving 442 patients, testing mechanical pumping devices were also methodologically flawed, and so pooled results need to be viewed cautiously. Mechanical pumping devices may protect against DVT (12/202 (6%) versus 42/212 (19%); Peto odds ratio 0.24; 95% confidence interval 0.13 to 0.44). Although the limited data indicated a potential benefit, they were inadequate to establish any effect on the incidence of pulmonary embolism and overall mortality. Problems with skin abrasion and compliance were reported. REVIEWER'S CONCLUSIONS: U and LMW heparins protect against lower limb DVT. There is insufficient evidence to confirm either protection against pulmonary embolism or overall benefit, or to distinguish between various applications of heparin. Foot and calf pumping devices appear to prevent DVT, may protect against pulmonary embolism, and reduce mortality, but compliance remains a problem. Good quality trials of mechanical methods as well as direct comparisons with heparin should be considered.

Anticoagulants↗
PubMed1990

Effects of obesity, social interactions, and physical environment on physical activity in preschoolers.

Examined demographic, environmental, and parent-child interactional correlates of physical activity in a group of 222 preschoolers. Activity levels were assessed with a system that quantified directly observed physical activity in the natural environment. Using regression-modeling procedures, results revealed a significant relationship between (a) child's relative weight, parental weight status, and percentage of time spent outdoors (environment) and (b) children's activity levels. Parental obesity was associated with lower levels of physical activity in children, childhood relative weight was associated with slightly higher levels of physical activity, and more outdoor activity was associated with higher activity levels. Parental participation in children's activities also significantly interacted with levels of parental obesity in predicting activity levels. Those children with a 50% risk for obesity (as defined by both, one, or neither parent being overweight) had small changes in activity across levels of parent-child interaction, whereas those at higher risk for obesity responded with increased activity as parent-child interactions increased. Results are discussed, and the implications of these findings for future intervention efforts are examined.

Child, Preschool↗
PubMed2002

Physical activity and its impact on health outcomes. Paper 1: The impact of physical activity on cardiovascular disease and all-cause mortality: an historical perspective.

The modern scientific study of physical activity began soon after World War II and focused on the epidemic of cardiovascular disease that was beginning to engulf the Western world. Early 'exercise prescriptions' then specified intense bouts of vigorous activity as the most effective way to maintain cardiovascular fitness and 'heart health'. Doctors and other health professionals then grew concerned that progressively fewer individuals were heeding this advice at a time when physical activity from manual work was becoming less common. Evidence was also emerging in the late 1980s that the value of accumulated, moderately intense activities, now of increasing importance during leisure time, may have been overlooked, or at least underplayed, in the prevention of heart disease, diabetes and some cancers. Perhaps in population terms adherence to moderate 'lifestyle' activities would be better than to the earlier vigorous recommendations. Social policy therefore shifted in the United States in 1996; the US Surgeon General's report set out the basic public health message of '30 min of moderate activity five, and preferably all, days of the week'. This recommendation was broadly adopted throughout much of the Western world. How this change in health strategy might impact on unhealthy weight gain and the growing obesity epidemic was given little attention. Here we examine how post-war public health policy in physical activity developed in an attempt primarily to prevent cardiovascular disease. In the following article we examine why too little attention may have been given to unhealthy weight gain and investigate how this may have happened. Then we consider how much physical activity--and of what kind--is needed to prevent unhealthy weight gain.

Adult↗
PubMed2002

Physical activity and its impact on health outcomes. Paper 2: Prevention of unhealthy weight gain and obesity by physical activity: an analysis of the evidence.

The current guidelines for physical activity are based on the prevention of cardiovascular disease. In this article the magnitude and type of physical activity required to prevent unhealthy weight gain are assessed. Five categories of analyses are considered, ranging from the most rigorous analyses (based on D2O18 measures of energy expenditure) to socio-ecological associations. To standardize the approach, published work on the extent of exercise was expressed as a physical activity level (PAL), i.e. the ratio of total expenditure to the measured or estimated basal metabolic rate. D2O18, direct monitoring and measurements of activity patterns and detailed prospective studies of substantial population groups all suggest that a PAL of > or = 1.8 is required to limit the proportion of overweight and obese adult men. Data on women are more difficult to interpret because women are less active and the relationship with physical activity is usually less clear. Post-obese women with a PAL of >1.75 do not regain weight and other data are consistent with the need for a PAL of > or = 1.8. The analyses in both sexes are based predominantly on adults living in a Western society with the ready availability of energy-dense foods. Vigorous activity is more clearly linked to weight stability, allows a higher intensity of exercise for general activities and shortens the time needed for achieving a PAL of 1.8. This activity level is equivalent to an additional 60-90 min of brisk walking in adults who normally undertake only modest exercise. These demands are greater than the current suggested levels for cardiovascular benefit and imply the need for different environmental policies, rather than health education policies, if societies are to become generally more active and avoid unhealthy weight gain.

Adolescent↗
PubMed2003

Cross talk between physical activity and appetite control: does physical activity stimulate appetite?

Physical activity has the potential to modulate appetite control by improving the sensitivity of the physiological satiety signalling system, by adjusting macronutrient preferences or food choices and by altering the hedonic response to food. There is evidence for all these actions. Concerning the impact of physical activity on energy balance, there exists a belief that physical activity drives up hunger and increases food intake, thereby rendering it futile as a method of weight control. There is, however, no evidence for such an immediate or automatic effect. Short (1-2 d)-term and medium (7-16 d)-term studies demonstrate that men and women can tolerate substantial negative energy balances of < or = 4 MJ energy cost/d when performing physical activity programmes. Consequently, the immediate effect of taking up exercise is weight loss (although this outcome is sometimes difficult to assess due to changes in body composition or fluid compartmentalization). However, subsequently food intake begins to increase in order to provide compensation for about 30% of the energy expended in activity. This compensation (up to 16 d) is partial and incomplete. Moreover, subjects separate into compensators and non-compensators. The exact nature of these differences in compensation and whether it is actually reflective of non-compliance with protocols is yet to be determined. Some subjects (men and women) performing activity with a cost of < or = 4 MJ/d for 14 d, show no change in daily energy intake. Conversely, it can be demonstrated that when active individuals are forced into a sedentary routine food intake does not decrease to a lower level to match the reduced energy expenditure. Consequently, this situation creates a substantial positive energy balance accompanied by weight gain. The next stage is to further characterize the compensators and non-compensators, and to identify the mechanisms (physiological or behavioural) that are responsible for the rate of compensation and its limits.

Anorexia↗
PubMed1990

Physical self-efficacy, perceived physical status, and depressive symptomatology in older adults.

Perceptions of physical, general, and social self-efficacy were assessed in 200 residents of a retirement village. The subjects were administered the Depression Adjective Checklist (Lubin, 1967a) and the CES-D Depression Scale (Radloff, 1977) and were asked to rate their physical status (number of health problems, number of monthly physician visits, and health and activity levels). Pearson correlations suggested strong relationships between the self-efficacy measures and depressive symptomatology. Most important, physical self-efficacy was seen to be the strongest predictor of depressive symptoms, much stronger than the objective physical status variables.

Activities of Daily Living↗
PubMed1992

Coping by individuals with physical disabilities with perceived challenge in physical activity: are people consistent?

This study examined coping and affective experience to perceived challenge in physical activity settings in 30 individuals with physical disabilities in three separate situations over 6 months. On every occasion, each individual was asked to report the most challenging physical activity of the preceding week and indicate how he or she coped with the challenge and what affective states were experienced. Coping was measured using a modification of Carver, Scheier, and Weintraub's (1989) COPE inventory. Self-reported mood was assessed using the Positive Affect Negative Affect Schedule (Watson, Clark, & Tellegen, 1988). The data indicated that perceived challenge was characterized by high levels of positive affect. Generalizability theory, used to determine the relative stability of coping strategies, indicated that individuals with physical disabilities did not consistently use the same coping skill strategies across settings.

Adaptation, Psychological↗
PubMed2005

Effects of body composition and leisure-time physical activity on transitions in physical functioning in the elderly.

Physical activity and body composition were examined with respect to variation in functional limitation over a 6-year period (four surveys conducted between 1994 and 2000) based on a cohort of 1,655 community-dwelling older women and men living in Sonoma, California. Measures of functional limitation and physical activity were based on standard self-report questions. Measures of body composition (lean mass, fat mass) were estimated from bioelectric impedance by using population-specific prediction equations derived from dual-energy x-ray absorptiometry. For women, a one-unit gain in lean mass:fat mass ratio reduced the report of limitation at all surveys 65.5% (95% confidence interval: 21.8, 87.4). A similar reduction was not observed for men; however, there was a 3% increase in the report of no limitation at any survey. The effect of high levels of physical activity reduced new functional limitation that occurred at the last survey by 36.8% (95% confidence interval: 0.0, 92.2) for men and 52.7% (95% confidence interval: 13.5, 91.9) for women. In summary, higher levels of physical activity appeared to reduce the risk of future functional limitation conditional on the level of functioning established early in the disablement process by lean mass:fat mass ratio.

Absorptiometry, Photon↗
PubMed2006

Incident fall risk and physical activity and physical performance among older men: the Osteoporotic Fractures in Men Study.

Physical activity and physical performance have been linked to fall risk in the elderly. The authors examined the relation between physical activity and physical performance with incident falls in the Osteoporotic Fractures in Men Study, a large prospective cohort study of 5,995 community-dwelling men in the United States at least 65 years of age. The authors also examined what types of activities are associated with falling. Incident falls between 2000 and 2005 were captured from up to 17 triannual follow-up questionnaires per participant and analyzed with generalized estimating equations. Follow-up averaged 4.5 years. The average risk of falling in the first 4 months of follow-up was 6.6%. The most active quartile had a significantly greater fall risk than did the least active quartile (relative risk = 1.18, 95% confidence interval (CI): 1.07, 1.29). Men with greater leg power and grip strength had significantly reduced fall risk (for highest leg power quartile vs. lowest: relative risk = 0.82, 95% CI: 0.73, 0.92; for highest grip strength quartile vs. lowest: relative risk = 0.76, 95% CI: 0.69, 0.85). Partitioning components of activity showed no association between fall risk and leisure activities but a positive association with household activities (for highest quartile vs.lowest: relative risk = 1.17, 95% CI: 1.07, 1.28).

Accidental Falls↗
PubMed2006

Effects of a physical activity intervention on measures of physical performance: Results of the lifestyle interventions and independence for Elders Pilot (LIFE-P) study.

BACKGROUND: The Short Physical Performance Battery (SPPB), which includes walking, balance, and chair stands tests, independently predicts mobility disability and activities of daily living disability. To date, however, there is no definitive evidence from randomized controlled trials that SPPB scores can be improved. Our objective was to assess the effect of a comprehensive physical activity (PA) intervention on the SPPB and other physical performance measures. METHODS: A total of 424 sedentary persons at risk for disability (ages 70-89 years) were randomized to a moderate-intensity PA intervention or a successful aging (SA) health education intervention and were followed for an average of 1.2 years. RESULTS: The mean baseline SPPB score on a scale of 0-12, with 12 corresponding to highest performance, was 7.5. At 6 and 12 months, the PA versus SA group adjusted SPPB (+/- standard error) scores were 8.7 +/- 0.1 versus 8.0 +/- 0.1, and 8.5 +/- 0.1 versus 7.9 +/- 0.2, respectively (p < .001). The 400-meter walking speed was also significantly improved in the PA group. The PA group had a lower incidence of major mobility disability defined as incapacity to complete a 400-meter walk (hazard ratio = 0.71, 95% confidence interval = 0.44-1.20). CONCLUSIONS: A structured PA intervention improved the SPPB score and other measures of physical performance. An intervention that improves the SPPB performance may also offer benefit on more distal health outcomes, such as mobility disability.

Activities of Daily Living↗