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Changes in physical activity, mortality, and incidence of coronary heart disease in older men.

BACKGROUND: We studied the relations between physical activity and changes in physical activity, all-cause mortality, and incidence of major coronary-heart-disease events in older men. METHODS: In 1978-80 (Q1), 7735 men aged 40-59 were selected from general practices in 24 British towns, and enrolled in a prospective study of cardiovascular disease, which included physical activity data. In 1992 (Q92), 12-14 years later, 5934 of the men (91% of available survivors, mean age 63 years) gave further information on physical activity and were then followed up for a further 4 years. The main endpoints were all-cause mortality during 4 years of follow-up from Q92, and major fatal and non-fatal coronary-heart-disease events during 3 years of follow-up from Q92. FINDINGS: Among 4311 men with no history of coronary heart disease, stroke, or "other heart trouble" by Q92 and who did not report "poor health", there were 219 deaths. In the inactive/occasionally active, light, moderate, and moderately vigorous/vigorous activity groups there were 101 (18.5/1000 person-years) 48 (11.4), 23 (7.3), and 47 (9.1) deaths, respectively (adjusted risk ratios 1.00, 0.61 [95% CI 0.48-0.86], 0.50 [0.31-0.79], 0.65 [0.45-0.94]). Men who were sedentary at Q1 and who began at least light activity by Q92 had significantly lower all-cause mortality than those who remained sedentary, even after adjustment for potential confounders (risk ratio=0.55 [0.36-0.84]). Physical activity improved both cardiovascular mortality (0.66 [0.35-1.23]) and non-cardiovascular mortality (0.48 [0.27-0.85]). The relation between physical activity at Q92, changes in physical activity, and mortality were similar for men with pre-existing cardiovascular disease. INTERPRETATION: Maintaining or taking up light or moderate physical activity reduces mortality and heart attacks in older men with and without diagnosed cardiovascular disease. Our results support public-health recommendations for older sedentary people to increase physical activity, and for active middle-aged people to continue their activity into old age.

Aged↗

Socioeconomic differences in leisure-time physical activity: the role of social participation and social capital in shaping health related behaviour.

Several studies have shown socioeconomic differences in leisure-time physical activity. One explanation may be socioeconomic differences in relevant psychosocial conditions. The Malmö Diet and Cancer Study is a prospective cohort study including inhabitants in Malmö, Sweden. The baseline questionnaire used in this cross-sectional study was completed by the 11,837 participants born 1926-1945 in 1992-1994. Leisure-time physical activity was measured by an item presenting a variety of activities. These activities were aggregated into a summary measure of leisure-time physical activity that takes both the intensity and duration of each specific activity into consideration. The effects of the psychosocial variables on the socioeconomic differences in leisure-time physical activity were calculated in a multivariate logistic regression analysis. The quartile with the lowest degree of leisure-time physical activity was not evenly distributed between the socioeconomic groups. Socioeconomic differences were seen as odds ratios 1.5 for skilled and 1.5 for unskilled male manual workers, compared to the high level non-manual employees. An OR 1.6 was observed for female unskilled manual workers. Self-employed men and female pensioners also had a significantly increased risk of low leisure-time physical activity. Adjustment for age, country of origin and previous/current diseases had no effect on these SES differences. Finally, adjusting for social participation almost completely erased the SES differences. Among the psychosocial variables, social participation was the strongest predictor of low physical activity, and a strong predictor for socioeconomic differences in low leisure-time physical activity. Social participation measures the individual's social activities in, for example political parties and organisations. It therefore seems possible that some of the socioeconomic differences in leisure-time physical activity are due to differing social capital between socioeconomic groups.

Cross-Sectional Studies↗

Physical activity social support and middle- and older-aged minority women: results from a US survey.

BACKGROUND: Many American adults remain sedentary despite many known health benefits. Research on the determinants of physical activity have indicated that social support is one of the strongest correlates, but little is known about this relation in important subgroups of middle and older-aged women. OBJECTIVE: The purpose of this study was to assess the association of physical activity-related social support on several measures of physical activity in a national sample of minority women. A unique aspect of these measures is the inclusion of vigorous household tasks and occupational physical activities. METHODS: The US Women's Determinants Study was conducted in 1996-1997. The survey was a modified-random sample, telephone survey of 2912 Black, Hispanic, American Indian/Alaskan Native, and White women age 40 and older. A composite score of physical activity social support (PASS) was analyzed as the independent variable in logistic regression analyses. Four measures of physical activity levels served as the dependent variables. A separate analysis was done to distinguish PASS from friends versus PASS from relatives. The potential confounding effect of race/ethnicity, marital status, age, income and education were evaluated and adjusted in the models. RESULTS: Hispanic women were more likely to have high PASS scores than the other racial/ethnic groups. Odds ratios indicate that subjects with high levels of PASS were significantly less likely to be sedentary than those with low support, even after adjusting for race/ethnicity. While there were significant associations among levels of social support and physical activity, this was not true for the measure of "regular exercise." There was no significant difference between the contribution of "friend" support versus "family" support on all four measures on physical activity. DISCUSSION: Based on our results, enhancing social support may be an important aspect of interventions aimed at increasing physical activity in a population of sedentary women of various racial/ethnic backgrounds. Also, "regular exercisers" in this population appear to be less reliant social support to maintain their behavior.

Adult↗

Fear of pain, physical performance, and attentional processes in patients with fibromyalgia.

Patients with fibromyalgia often present with increased levels of disability and physical functioning, for which the determinants are still unclear. In patients with other musculoskeletal pain syndromes, such as chronic low back pain, physical performance and disability levels are shown to be strongly associated with pain-related fear, and even stronger than pain severity. The present study was aimed at examining the role of pain-related fear and attentional processes on tolerance for physical activity in fibromyalgia patients. High and low fearful fibromyalgia patients (N=81) were requested to perform a physical task, a cognitive (reaction time) task, and a dual task in which the physical and cognitive tasks were combined. It was hypothesized that high fearful patients would terminate the physical performance task sooner than low fearful patients, and would show a greater disruption on the cognitive task. In addition, it was expected that when distracted in the dual task, high fearful patients would show improved performance on the physical task after a fear reduction instruction. The results showed that pain itself was a greater predictor of activity tolerance than pain-related fear, but that pain-related fear was the stronger predictor of reaction times on the cognitive task. Also, all groups showed equal improvement in physical performance in the dual task. The findings suggest that baseline pain acts as an occasion setter which determines the level of physical activity the patient is willing to perform, regardless of pain increase and threat-reducing instructions.

Adult↗

A prospective, randomized study addressing the need for physical simulation following virtual simulation.

PURPOSE: To accurately implement a treatment plan obtained by virtual or CT simulation, conventional or physical simulation is still widely used. To evaluate the need for physical simulation, we prospectively randomized patients to undergo physical simulation or no additional simulation after virtual simulation. METHODS AND MATERIALS: From July 1995 to September 1996, 75 patients underwent conformal four-field radiation therapy planning for prostate cancer with a commercial grade CT simulator. The patients were randomized to undergo either port filming immediately following physical simulation or port filming alone. The precision of implementing the devised plan was evaluated by comparing simulator radiographs and/or port films against the digitally reconstructed radiographs (DRRs) for x, y, and z displacements of the isocenter. Changes in beam aperture were also prospectively evaluated. RESULTS: Thirty-seven patients were randomized to undergo physical simulation and first day port filming, and 38 had first day treatment verification films only without a physical simulation. Seventy-eight simulator radiographs and 195 first day treatment port films were reviewed. There was no statistically significant reduction in treatment setup error (>5 mm) if patients underwent physical simulation following virtual simulation. No patient required a resimulation, and there was no significant difference in changes of beam aperture. CONCLUSIONS: Following virtual simulation, physical simulation may not be necessary to accurately implement the conformal four-field technique. Because port filming appears to be sufficient to assure precise and reliable execution of a devised treatment plan, physical simulation may be eliminated from the process of CT based planning when virtual simulation is available.

Computer Simulation↗

Assessment of participation in physical activities and relationship to socioeconomic and health factors. The controversial value of self-perception.

Physician counseling on physical activities for sedentary people is usually based on anamneses. The aim of the present study was to investigate the accuracy of self-perception of participation in physical activities, and the correlation of physical activity with background factors. A random sample of 276 individuals aged 20-65 years completed a detailed questionnaire on type and intensity of physical activity and associated socioeconomic and health factors. Physical activities were divided into work, leisure-time, and sports and rated according to Baecke's four-item index. In addition, subjects answered a yes/no item that resembled the general question regarding physical activity usually asked by physicians in a typical anamnesis. About half of the population was found to lead a sedentary life-style. The lower the level of education, the greater the physical activity at work. Males had a higher sports index than females. Interestingly, 1.3% of those with a high questionnaire score reported on the anamnesis question that they did not engage in regular physical activity, whereas 17.5% with a low questionnaire score answered "yes" to the last item. In conclusion, self-reports on physical activity may be inaccurate and to ensure proper counseling, primary care physicians must place greater weight on the patient history.

Adult↗

Personal, social, and environmental correlates of physical activity in North Carolina Latina immigrants.

BACKGROUND: Few studies have examined the correlates of physical activity for Latinas (Latino women) that provide critical information for developing culturally competent interventions. The objective of this study was to describe physical activity and the personal, social environmental, and physical environmental correlates for Latina immigrants. METHODS: As part of the multisite Women's Cardiovascular Health Network Project, 671 first-generation Latina immigrants, aged 20 to 50 years who were living in North Carolina, completed an in-person interview. All statistical models were adjusted for acculturation, with self-reported physical activity as the dependent variable. RESULTS: Only 37% of the Latinas reported meeting vigorous or moderate recommendations for physical activity, with 42% insufficiently active and 21% inactive. Women with more self-efficacy (confidence that they could exercise more) were less likely to meet recommendations for activity. Social environmental factors, such as knowing people who exercise or seeing people exercise in the neighborhood, were more likely among women who reported any activity or who met recommendations for activity. Physical environmental factors, such as vehicular traffic and street lighting, were not strongly associated with physical activity. Living in a community where places to exercise were available was associated with any activity. CONCLUSIONS: This study underscores the importance of understanding personal characteristics and addressing factors that reflects the social and physical environment where Latinas live. Future programs aimed at increasing physical activity among Latina immigrants should consider such factors, particularly factors from the social environment.

Adult↗

Commuting to school: are children who walk more physically active?

BACKGROUND: The journey to school is an opportunity for increasing children's daily physical activity. However, the contribution that active commuting to school makes to overall physical activity is unknown. This study used objective measurement to investigate the physical activity patterns of children by mode of travel to school. METHODS: Primary-school children wore an accelerometer programmed to record minute-by-minute physical activity for 7 days and completed a brief questionnaire describing their usual travel to school. The total volume of physical activity and the time spent in activity of at least moderate intensity, as recorded by the accelerometer, was estimated for weekdays and the weekend, and groups of children were compared by mode of transport to school. Data were collected in May/June 2002. RESULTS: Of the 114 children (59 boys, 55 girls; aged 10.4+/-0.8 years) who took part in the study, those who walked to school (65%) were significantly more active than those who traveled by car (712.0+/-206.7 vs 629.9+/-207.2 accelerometer counts per minute, p=0.05). Analysis by gender indicated that the major differences in physical activity between travel groups were seen only in boys. Hourly activity patterns demonstrated that boys who walked to school were more active after school and throughout the evening than were car users. CONCLUSIONS: In boys, walking to school was associated with higher physical activity after school and during the evening. Active transport may contribute to a more physically active profile, at least for boys, supporting walk-to-school initiatives to increase children's physical activity.

Child↗

Effect of physical exercise on seizure occurrence in a model of temporal lobe epilepsy in rats.

Although the favorable effect of physical fitness on general health is unquestionable, physical exercise and fitness programs in patients with epilepsy are still a matter of controversy. Little objective evidence regarding the effect of exercise on seizure frequency and severity has been reported. One sought to clarify the relationship between exercise and epilepsy in an animal model of temporal lobe epilepsy (the pilocarpine model of epilepsy). To evaluate the effect of an aerobic physical program on seizure frequency, 29 epileptic animals were continuously monitored during 24 h for 135 days after the first spontaneous recurrent seizure (SRS) and divided into three groups. The first group (N = 14) was submitted to an aerobic exercise program (training group). The second group (N = 7) was maintained in the treadmill for the same time as the training group without being submitted to physical exercise (sham group). The third group (N = 8) served as control. The behavioral observation was divided in three periods of 45 days. The first period was used to determine the number of seizures before physical training program. The second period was utilized to determine the number of seizures during the physical training program. The third period was used to analyze the frequency of seizures after the physical training program. The mean frequency of seizures in the control and sham groups increased significantly from period 1 to period 2 and from period 1 to period 3. However, in the training group, the frequency of seizures did not change significantly between the three periods of 45 days of observation. When the same periods of the three groups were analyzed together, a significant reduction in seizure frequency was observed comparing the training group with the control and sham groups during the period of physical training. The data presented in this study suggest that physical exercise is not a seizure-inducing factor in this experimental model of epilepsy.

Animals↗

Too hot to trot? Exploring potential links between climate change, physical activity and health.

Based on an analysis of existing literature, this paper explores the links between climate change, physical activity and health. It highlights the importance of physical activity for health, explores current understandings of factors influencing participation in sport and physical activity, and develops some hypotheses about the ways in which climate change may impact on the factors influencing physical activity and thereby on the level of participation in physical activity. The paper argues that climate change has the potential to be a barrier to participation in physical activity, particularly in areas where temperatures are already relatively high, and that a reduction in physical activity across the population is likely to have detrimental health impacts. The need for research to clarify the nature and extent of the threat posed to physical activity participation is highlighted, as is the need to take into account the direct and indirect costs of any changes or reductions in physical activity in any assessment of the costs of climate change and/or its mitigation.

Australia↗

Does co-morbid depressive illness magnify the impact of chronic physical illness? A population-based perspective.

OBJECTIVE: To examine the relative and combined impact of depressive and chronic physical conditions on functional status and health-care use in the general population. METHOD: Canadian, representative, population-based cross-sectional survey (n=130,880). Major depressive disorder (MDD) in the past 12 months was assessed by structured interview, and physical disorders, activity reduction, role impairment and work absence by self-report. The relative impact of MDD and six common chronic physical illnesses (asthma, arthritis, back problems, chronic obstructive pulmonary disease, heart disease and diabetes) was estimated using multivariate regression, adjusting for sociodemographic characteristics and overall chronic physical illness burden. RESULTS: After adjusting for sociodemographic characteristics, alcohol dependence and chronic physical illness burden, the presence of co-morbid MDD was associated with significantly greater (approximately double the) likelihood of health-care utilization and increased functional disability and work absence compared to the presence of a chronic physical illness without co-morbid MDD. This impact of MDD was seen across each of the six chronic physical illnesses examined in this study, with the strongest associations seen for work absence. CONCLUSIONS: These observations confirm prior findings of a strong association at the population level between major depression and health-care use and role impairment among persons with chronic physical disorders. They also point to the significant impact of co-morbid major depression on health-care seeking, disability and work absence in persons with chronic physical illness, underscoring the need for greater efforts to design and test the impact of detection and treatment programs for such individuals.

Activities of Daily Living↗

Physical activity and energy balance.

Energy expenditure rises above resting energy expenditure when physical activity is performed. The activity-induced energy expenditure varies with the muscle mass involved and the intensity at which the activity is performed: it ranges between 2 and 18 METs approximately. Differences in duration, frequency and intensity of physical activities may create considerable variations in total energy expenditure. The Physical Activity Level (= total energy expenditure divided by resting energy expenditure) varies between 1.2 and 2.2-2.5 in healthy adults. Increases in activity-induced energy expenditure have been shown to result in increases in total energy expenditure, which are usually greater than the increase in activity-induced energy expenditure itself. No evidence for increased spontaneous physical activity, measured by diary, interview or accelerometer, was found. However, this does not exclude increased physical activity that can not be measured by these methods. Part of the difference may also be explained by the post-exercise elevation of metabolic rate. If changes in the level of physical activity affect energy balance, this should result in changes in body mass or body composition. Modest decreases of body mass and fat mass are found in response to increases in physical activity, induced by exercise training, which are usually smaller than predicted from the increase in energy expenditure. This indicates that the training-induced increase in total energy expenditure is at least partly compensated for by an increase in energy intake. There is some evidence that the coupling between energy expenditure and energy intake is less at low levels of physical activity. Increasing the level of physical activity for weight loss may therefore be most effective in the most sedentary individuals.

Body Composition↗

Correlation between physical performance and fatigue in cancer patients.

BACKGROUND: Fatigue and a reduction in physical ability are common and often severe problems of cancer patients regardless of disease stage and modality of treatment. However, while physical performance can be assessed objectively with laboratory tests, fatigue is a subjective phenomenon whose perception is influenced by past experience and expectations for the future. PATIENTS AND METHODS: To evaluate the correlation between fatigue and physical impairment, we assessed maximal physical performance with a treadmill test, and mental state with two questionnaires, the Profile of Mood States (POMS) and the Symptom Check List (SCL-90-R), in a successive series of 78 cancer patients with solid tumors or hematological malignancies. RESULTS: A weak association between fatigue and maximal physical performance was found (r = -0.30; P < 0.01). However, intensity of fatigue showed a strong correlation with several indicators of psychological distress such as depression (r = 0.68), somatization (r = 0.64) and anxiety (r = 0.63; P for all < 0.001). Furthermore, patients with lower levels of physical performance had significantly higher scores for depression (P = 0.005), somatization (P = 0.03) and anxiety (P = 0.08), and significantly lower scores for vigor (P = 0.05) than their counterparts whose physical performance was higher. CONCLUSIONS: We conclude that fatigue in cancer patients may be related to mood disturbance but appears to be independent of physical performance. Moreover, low physical performance can be viewed as an independent predictor of mental distress in cancer patients.

Adolescent↗

A review of physical activity and prostate cancer risk.

OBJECTIVES: The purpose was to review the etiologic role and the possible biologic mechanisms for physical activity in the primary prevention of prostate cancer and to identify future research priorities. METHODS: We conducted literature searches and systematically reviewed all the epidemiologic studies of physical activity and prostate cancer and the literature on the underlying biologic mechanisms. RESULTS: Among 24 previously conducted studies, 14 studies suggested an inverse association of physical activity on prostate cancer; however, no overall association was found in six studies and an increased risk of prostate cancer was observed amongst the most physically active men in four other studies. The methodologic limitations in these studies include variations in detection of latent disease and possible outcome misclassification, crude assessments of physical activity, inadequate control for confounding, and incomplete examination of effect modification. CONCLUSIONS: Physical activity may have an inverse association with prostate cancer risk; however, the epidemiologic evidence is currently inconsistent and the magnitude of the risk reduction observed is small. These inconsistent results could be attributable, in part, to methodologic limitations of previous studies. Hence, further investigation of the etiologic role of physical activity is needed before more definitive conclusions can be made. Specifically, research studies should be designed to measure all types and parameters of physical activity throughout lifetimes. Furthermore, a better understanding of the biologic mechanisms and etiologically relevant time periods in prostate carcinogenesis when physical activity may be operative is needed, so that these studies can be properly designed.

Exercise↗

Physical activity and risk of colon cancer: the Physicians' Health Study (United States).

Previous studies indicate that physical activity is related inversely to colon cancer risk. However, details regarding that association--whether a dose-response relation exists, whether the relation differs between non-obese and obese persons, the effect of long-term physical activity--are unclear. We examined these issues in the Physicians' Health Study (United States). Physical activity was assessed at baseline among 21,807 men, aged 40 to 84 years, and again 36 months later. Men were followed for an average of 10.9 years (from baseline) during which 217 developed colon cancer. After adjusting for potential confounders (including age, obesity, and alcohol intake), the relative risks for colon cancer associated with vigorous exercise in times per week (< 1, 1, 2-4, 5+, at baseline) were 1.0 (referent); 1.1 (95% confidence interval [CI] = 0.7-1.7); 1.2 (CI = 0.8-1.6); and 1.1 (CI = 0.7-1.6), respectively; P trend = 0.6. Physical activity was not associated significantly with colon cancer risk either among non-obese or obese men. When we used physical activity assessments at baseline as well as at 36 months, physical activity again was unrelated to colon cancer risk. These data do not support the hypothesis that physical activity reduces the risk of colon cancer. Plausible alternate explanations for the null finding include misclassification of physical activity and the potential for increased surveillance for colon cancer ('screening effect') among those physically active.

Adult↗

Psychological aggression predicts physical aggression in early marriage.

Psychological aggression by self and partner, physical aggression by the partner, and marital dissatisfaction were examined as longitudinal predictors of first instances of physical aggression during marriage. Subjects who were not physically aggressive at a premarital assessment were selected from a sample of 393 engaged couples. Couples participated in three subsequent assessments over the first 30 months of marriage. As hypothesized, individuals' own psychological aggression predicted their initial incidents of physical aggression in marriage. Psychological aggression by their partners also predicted initial incidents of physical aggression. Prior physical aggression by their partners was inconsistently associated with first instances of physical aggression. Contrary to our hypothesis, previous levels of marital dissatisfaction did not predict initial incidents of physical aggression. These findings were consistent across sexes. The results underscore the progression from psychological to physical abuse and have clear implications for understanding the development and prevention of interspousal aggression.

Adult↗

Leisure-time physical activity and reduced plasma levels of obesity-related inflammatory markers.

OBJECTIVE: This study investigated the relationship between physical activity and the obesity-related inflammatory markers C-reactive protein, interleukin-6, and soluble tumor necrosis factor receptors (sTNF-Rs) 1 and 2. Furthermore, we examined the relationship between physical activity and insulin sensitivity (insulin, C-peptide, and hemoglobin A(1c) levels) and whether inflammatory markers mediate this association. RESEARCH METHODS AND PROCEDURES: Biomarkers were measured in 405 healthy men and 454 healthy women from two large ongoing prospective studies. Information about physical activity and other variables was assessed by questionnaires. RESULTS: After adjustment for other predictors of inflammation, physical activity was inversely associated with plasma levels of sTNF-R1, sTNF-R2, interleukin-6, and C-reactive protein (p = 0.07, p = 0.004, p = 0.04, and p = 0.009). After further adjustment for BMI and leptin, as a surrogate for fat mass, most of these associations were no longer significant. Physical activity was also inversely related to insulin and C-peptide levels (p = 0.008 and p < 0.001); however, in contrast to BMI and leptin, levels of inflammatory markers explained only very little of this inverse relationship. DISCUSSION: These results suggest that frequent physical activity is associated with lower systemic inflammation and improved insulin sensitivity. These associations can partially be explained by a lower degree of obesity in physically active subjects. Although inflammatory markers may mediate obesity-dependent effects of physical activity on inflammatory related diseases such as type 2 diabetes or coronary heart disease, our study suggests that they do not directly account for the beneficial effects of physical activity on insulin resistance.

Adult↗

Physical activity among African-American girls: the role of parents and the home environment.

OBJECTIVES: African-American girls are at increased risk for becoming overweight. Increased physical activity may prevent this. This study examines measurements of girls' physical activity and associations with: BMI, parent's reported self-efficacy and support for helping daughters be active, girl's perceived support from parents for physical activity, parent's and girl's perceived neighborhood safety and access to facilities, and family environment. RESEARCH METHODS AND PROCEDURES: Fifty-two 8- to 10-year-old African-American girls and their primary caregiver in the Minneapolis/St. Paul area participated in the Girls Health Enrichment Multisite Studies pilot intervention to prevent weight gain by promoting healthy eating and physical activity. Data collected included height, weight, physical activity level, and physical activity-related psychosocial measures from girl and parent. Girls wore an activity monitor for 3 days to assess activity level. Correlations were computed among the average minutes per day of moderate to vigorous activity between 12 pm and 6 pm and BMI and psychosocial measures. RESULTS: BMI was inversely correlated with moderate to vigorous activity (r = -0.35, p < 0.01), whereas parent's self-efficacy for supporting daughter to be active was positively correlated with activity (r = 0.45, p < 0.001). There was a trend for parent's reported support of daughter's activity level to be associated with activity (r = 0.26, p < 0.06). Girl's perception of parent's support for physical activity, perceived neighborhood safety and access to facilities, and family environment were not associated with girl's activity levels. DISCUSSION: Interventions to increase physical activity among preadolescent African-American girls may benefit from a parental component to encourage support and self-efficacy for daughters' physical activity.

Black or African American↗