Physical activity during leisure time and primary prevention of coronary heart disease: an updated meta-analysis of cohort studies. ACTA ACUST UNITED AC. 2008;15:247-257. [PMID: 18525378 DOI: 10.1097/hjr.0b013e3282f232ac]

Associations of objectively measured sedentary behavior, light activity, and markers of cardiometabolic health in young women

PURPOSE

To investigate the associations among objectively measured sedentary behavior, light physical activity, and markers of cardiometabolic health in young women.

METHODS

Cardiovascular disease risk factors, homeostasis model assessment for insulin resistance (HOMA-IR), lipid accumulation product, and inflammatory markers were measured in 50 young, adult women. Accelerometers were worn over 7 days to assess sedentary time (<150 counts min(-1)), light physical activity (150-2,689 counts min(-1)), and moderate-to-vigorous physical activity (MVPA; ≥2,690 counts min(-1)). Multivariate regression examined independent associations of sedentary behavior and light physical activity with cardiometabolic health. Covariates included MVPA, cardiorespiratory fitness (VO2peak) and body mass, and body composition.

RESULTS

Sedentary behavior was associated with triglycerides (p = 0.03) and lipid accumulation product (p = 0.02) independent of MVPA. These associations were attenuated by VO2peak and body mass or body composition (p ≥ 0.05). Light physical activity was independently associated with triglycerides and lipid accumulation product after adjustment for all covariates (p < 0.05). The association between light physical activity and HOMA-IR was independent of MVPA (p = 0.02) but was attenuated by VO2peak and body mass or body composition (p > 0.05).

CONCLUSIONS

Sedentary behavior and light physical activity were independently associated with markers of cardiometabolic health in young, adult women. Our data suggest that VO2peak and body composition may be important mediators of these associations. Decreasing sedentary behavior and increasing light physical activity may be important for maintaining cardiometabolic health in young, adult women.

Long-term effect of different physical activity levels on subclinical atherosclerosis in middle-aged men: a 25-year prospective study

BACKGROUND

The purpose of the study was to investigate the influence of lifetime physical activity (PA) on selected indices of atherosclerosis in longitudinal observation of middle-aged men.

METHODS

The subject of the study was a cohort of 101 men (mean age 59,7 ± 9,0 years), free of cardiovascular symptoms and treatment, participating in follow-up examinations in the years 1985/90-2011/12. Self-report PA was assessed by interviewer-administered Seven-Day PA Recall and Historical PA questionnaire. Subclinical atherosclerosis was measured by assessing the coronary artery calcification (CAC) according to Agatston's method using multi-slice computed tomography; the carotid intima-media thickness (IMT) using high-resolution B-mode ultrasound; and the reactive hyperemia index (RHI) using peripheral arterial tonometry (EndoPAT2000). The participants were initially divided into three groups according to tertiles of exercise-related energy expenditure (EE) in kcal/week at baseline, i.e. <2050 (low-to-moderate; n = 33), 2050-3840 (high; n = 34), >3840 (very high; n = 34).

RESULTS

The low-to-moderate, high and very high PA groups were comparable in terms of age and atherosclerosis risk factors at baseline. No linear relationship was found between PA and CAC, IMT and RHI. Men who maintained low-to-moderate (n = 26), high (n = 21) and very high (n = 15) PA level had the mean CAC of 286.1 ± 361.9, 10.7 ± 28.9, and 106.1 ± 278.3 (p<0.001 for low-to moderate vs high; p<0.05 for low-to-moderate vs very high); the mean IMT of 0.751 ± 0.19 mm, 0,641 ± 0.26 mm, and 0.750 ± 0.60 mm (p>0.05); and the mean RHI of 1.69 ± 0.4, 2.00 ± 0.4, and 2.13 ± 0.5 (p for trend = 0.050), respectively. No cases of CAC>400, IMT ≥ 0.9 and RHI<1.67 were noted only among men with maintained high PA level. At final examination men with high and very high PA had more favorable cardiometabolic profile than men with lower PA.

CONCLUSIONS

Maintaining regular high PA level through young and middle adulthood may protect against atherosclerosis as measured by CAC, IMT and RHI.

A community-based exercise intervention transitions metabolically abnormal obese adults to a metabolically healthy obese phenotype

BACKGROUND

Lower habitual physical activity and poor cardiorespiratory fitness are common features of the metabolically abnormal obese (MAO) phenotype that contribute to increased cardiovascular disease risk. The aims of the present study were to determine 1) whether community-based exercise training transitions MAO adults to metabolically healthy, and 2) whether the odds of transition to metabolically healthy were larger for obese individuals who performed higher volumes of exercise and/or experienced greater increases in fitness.

METHODS AND RESULTS

Metabolic syndrome components were measured in 332 adults (190 women, 142 men) before and after a supervised 14-week community-based exercise program designed to reduce cardiometabolic risk factors. Obese (body mass index ≥30 kg · m(2)) adults with two to four metabolic syndrome components were classified as MAO, whereas those with no or one component were classified as metabolically healthy but obese (MHO). After community exercise, 27/68 (40%) MAO individuals (P<0.05) transitioned to metabolically healthy, increasing the total number of MHO persons by 73% (from 37 to 64). Compared with the lowest quartiles of relative energy expenditure and change in fitness, participants in the highest quartiles were 11.6 (95% confidence interval: 2.1-65.4; P<0.05) and 7.5 (95% confidence interval: 1.5-37.5; P<0.05) times more likely to transition from MAO to MHO, respectively.

CONCLUSION

Community-based exercise transitions MAO adults to metabolically healthy. MAO adults who engaged in higher volumes of exercise and experienced the greatest increase in fitness were significantly more likely to become metabolically healthy. Community exercise may be an effective model for primary prevention of cardiovascular disease.

Association between neighborhood deprivation and fruits and vegetables consumption and leisure-time physical activity: a cross-sectional multilevel analysis

Background

Most studies of the association between neighborhood socioeconomic deprivation and individual lifestyles leading to cardiovascular disease focused on a single cardiovascular risk factor. The concomitant assessment of more than one risk factor may provide clues to specific mechanisms linking neighborhood disadvantage to individual lifestyles. We investigated the association of neighborhood deprivation with fruits and vegetables consumption and leisure-time physical activity in adults living in an urban center in Portugal.

Methods

In 1999–2003, we assembled a random sample of 2081 adult residents in the city of Porto. Data on sociodemographic characteristics were collected by trained interviewers using structured questionnaires. Fruits and vegetables consumption was estimated using a validated 82-item semiquantitative food frequency questionnaire covering the previous year and expressed in portions per day. Physical activity was evaluated using a questionnaire exploring leisure-time activities over the previous year and expressed in metabolic equivalents (MET).minute/day. Self-reported address was used to place individuals in neighborhoods. Neighborhoods’ socioeconomic characterization was based on aggregated data at the census block level provided by the 2001 National Census. Latent class analysis models were used to identify three discrete socioeconomic classes of neighborhoods. Random effects models with random intercepts at the neighborhood level were used to explore clustering and contextual effects of neighborhood deprivation on each of the outcomes.

Results

We found evidence of neighborhood clustering of fruits and vegetables consumption and leisure-time physical activity that persisted after adjustment for neighborhood deprivation only among women. Women living in the most deprived neighborhoods presented a consumption increase of 0.43 (95% CI: -0.033 to 0.89) portions of fruits and vegetables per day and a decrease in leisure-time physical activity of 47.8 (95% CI: -91.8 to 1.41) MET.minute/day, when compared to those living in the most affluent neighborhoods. Among men, no contextual neighborhood deprivation effects were observed.

Conclusion

Overall, neighborhood deprivation had a small effect on the consumption of fruits and vegetables and leisure-time physical activity. Neighborhood factors other than socioeconomic deprivation may still impact on the studied outcomes among women. This study provides relevant information for the design of interventions directed to neighborhood characteristics in the prevention of cardiovascular diseases.

Cognitive health begins at conception: addressing dementia as a lifelong and preventable condition

BACKGROUND

Dementia is a major public health problem that poses an increasing burden on the health and wealth of societies worldwide. Because the efficacy of current treatments is limited, increasing efforts are required to prevent the diseases that cause dementia.

DISCUSSION

We consider the evidence that lifelong prevention strategies may be an effective way to tackle the national burden of dementia in the absence of a cure. The links between lifestyle and cardiovascular disease are widely understood and accepted, but health professionals and patients remain unconvinced about the extent to which risk for dementia can be modified. However, there is strong evidence that at least half of risk for dementia is attributable to lifestyle factors such as diet, exercise and smoking. Moreover, the disease processes that result in dementia develop over several decades, implying that attempts to ameliorate them need to start early in life. Some modifiable risk factors for dementia act from the earliest stages of life, including in utero.

SUMMARY

Rebalancing efforts from the development of treatments to increased emphasis on prevention may be an alternative means to reducing the impact of dementia on society.

Dose-response association of physical activity with acute myocardial infarction: do amount and intensity matter?

OBJECTIVE

The aims of this study were to analyze the dose-response association between leisure time physical activity (PA) practice and myocardial infarction (MI), considering not only the total amount but also the amount of PA at different levels of intensity, and to determine whether these associations were modified by age.

METHOD

In a population-based age- and sex-matched case-control study, all first acute MI patients aged 25 to 74 years were prospectively registered in four Spanish hospitals between 2002 and 2004. Controls were randomly selected from population-based samples recruited during the same period of time. The Minnesota PA questionnaire was administered to assess total energy expenditure in PA and in light-, moderate-, and high-intensity PA.

RESULTS

Finally, 1339 cases and 1339 controls were included. The association between PA and MI likelihood was non-linear, with significantly lower MI odds at low practice levels (≥ 500 MET·min/week), lowest odds around 1500 MET·min/week, and a plateau thereafter. Light- (in subjects older than 64 years), moderate-, and high-intensity PA produced similar benefits.

CONCLUSION

Most of the population could reduce their likelihood of MI by engaging in PA at a moderate level of intensity or, in individuals older than 64 years, at a light level of intensity.

Enhanced autophagy ameliorates cardiac proteinopathy

Basal autophagy is a crucial mechanism in cellular homeostasis, underlying both normal cellular recycling and the clearance of damaged or misfolded proteins, organelles and aggregates. We showed here that enhanced levels of autophagy induced by either autophagic gene overexpression or voluntary exercise ameliorated desmin-related cardiomyopathy (DRC). To increase levels of basal autophagy, we generated an inducible Tg mouse expressing autophagy-related 7 (Atg7), a critical and rate-limiting autophagy protein. Hearts from these mice had enhanced autophagy, but normal morphology and function. We crossed these mice with CryABR120G mice, a model of DRC in which autophagy is significantly attenuated in the heart, to test the functional significance of autophagy activation in a proteotoxic model of heart failure. Sustained Atg7-induced autophagy in the CryABR120G hearts decreased interstitial fibrosis, ameliorated ventricular dysfunction, decreased cardiac hypertrophy, reduced intracellular aggregates and prolonged survival. To determine whether different methods of autophagy upregulation have additive or even synergistic benefits, we subjected the autophagy-deficient CryABR120G mice and the Atg7-crossed CryABR120G mice to voluntary exercise, which also upregulates autophagy. The entire exercised Atg7-crossed CryABR120G cohort survived to 7 months. These findings suggest that activating autophagy may be a viable therapeutic strategy for improving cardiac performance under proteotoxic conditions.

Current mHealth technologies for physical activity assessment and promotion

CONTEXT

Novel mobile assessment and intervention capabilities are changing the face of physical activity (PA) research. A comprehensive systematic review of how mobile technology has been used for measuring PA and promoting PA behavior change is needed.

EVIDENCE ACQUISITION

Article collection was conducted using six databases from February to June 2012 with search terms related to mobile technology and PA. Articles that described the use of mobile technologies for PA assessment, sedentary behavior assessment, and/or interventions for PA behavior change were included. Articles were screened for inclusion and study information was extracted.

EVIDENCE SYNTHESIS

Analyses were conducted from June to September 2012. Mobile phone-based journals and questionnaires, short message service (SMS) prompts, and on-body PA sensing systems were the mobile technologies most utilized. Results indicate that mobile journals and questionnaires are effective PA self-report measurement tools. Intervention studies that reported successful promotion of PA behavior change employed SMS communication, mobile journaling, or both SMS and mobile journaling.

CONCLUSIONS

mHealth technologies are increasingly being employed to assess and intervene on PA in clinical, epidemiologic, and intervention research. The wide variations in technologies used and outcomes measured limit comparability across studies, and hamper identification of the most promising technologies. Further, the pace of technologic advancement currently outstrips that of scientific inquiry. New adaptive, sequential research designs that take advantage of ongoing technology development are needed. At the same time, scientific norms must shift to accept "smart," adaptive, iterative, evidence-based assessment and intervention technologies that will, by nature, improve during implementation.

Joint associations of alcohol consumption and physical activity with all-cause and cardiovascular mortality

Individual associations of alcohol consumption and physical activity with cardiovascular disease are relatively established, but the joint associations are not clear. Therefore, the aim of this study was to examine prospectively the joint associations between alcohol consumption and physical activity with cardiovascular mortality (CVM) and all-cause mortality. Four population-based studies in the United Kingdom were included, the 1997 and 1998 Health Surveys for England and the 1998 and 2003 Scottish Health Surveys. In men and women, respectively, low physical activity was defined as 0.1 to 5 and 0.1 to 4 MET-hours/week and high physical activity as ≥5 and ≥4 MET-hours/week. Moderate or moderately high alcohol intake was defined as >0 to 35 and >0 to 21 units/week and high levels of alcohol intake as >35 and >21 units/week. In total, there were 17,410 adults without prevalent cardiovascular diseases and complete data on alcohol and physical activity (43% men, median age 55 years). During a median follow-up period of 9.7 years, 2,204 adults (12.7%) died, 638 (3.7%) with CVM. Cox proportional-hazards models were adjusted for potential confounders such as marital status, social class, education, ethnicity, and longstanding illness. In the joint associations analysis, low activity combined with high levels of alcohol (CVM: hazard ratio [HR] 1.95, 95% confidence interval [CI] 1.28 to 2.96, p = 0.002; all-cause mortality: HR 1.64, 95% CI 1.32 to 2.03, p <0.001) and low activity combined with no alcohol (CVM: HR 1.93, 95% CI 1.35 to 2.76, p <0.001; all-cause mortality: HR 1.50, 95% CI 1.24 to 1.81, p <0.001) were linked to the highest risk, compared with moderate drinking and higher levels of physical activity. Within each given alcohol group, low activity was linked to increased CVM risk (e.g., HR 1.48, 95% CI 1.08 to 2.03, p = 0.014, for the moderate drinking group), but in the presence of high physical activity, high alcohol intake was not linked to increased CVM risk (HR 1.32, 95% CI 0.52 to 3.34, p = 0.555). In conclusion, high levels of drinking and low physical activity appear to increase the risk for cardiovascular and all-cause mortality, although these data suggest that physical activity levels are more important.

Using the Internet to help with diet, weight, and physical activity: results from the Health Information National Trends Survey (HINTS)

Background

The Internet offers a viable platform for cost-effective and wide-reaching health interventions. However, little is known about use of the Internet to help with diet, weight, and physical activity (DWPA) using a nationally representative sample from the United States.

Objective

To (1) assess the demographic characteristics of people who use the Internet to help with DWPA, (2) assess whether usage trends changed over time, and (3) investigate the associations between using the Internet for DWPA and health behaviors.

Methods

Data on Internet users from the 2007 and 2011 iterations of the Health Information National Trends Survey (HINTS), N=4827 were analyzed using multiple logistic regression to determine the demographic correlates of using the Internet for help with DWPA. Multiple linear regression was used to test the associations between Internet use for DWPA and three health behaviors: fruit intake, vegetable intake, and physical activity.

Results

A larger percentage of Internet users used the Internet for DWPA in 2011 (42.83%) than in 2007 (40.43%). In general, Internet users who were younger (OR 0.98, P<.001), more educated (OR 1.40, P<.001), married (OR 1.06, P=.03), of a minority race (non-Hispanic blacks: OR 1.14, P=.02; Hispanics: OR 1.42, P=.01), and who had a higher Body Mass Index (BMI) (OR 1.04, P<.001) were more likely to use the Internet for DWPA. Across survey years, gender was not associated with using the Internet for DWPA (OR 1.03, P=.12), but there was a significant interaction between survey year and gender (OR 1.95, P=.002); in 2007, men were more likely to use the Internet for DWPA, but women were more likely to do so in 2011. Using the Internet for DWPA was associated with more vegetable intake (B=.22, P=.002), more fruit intake (B=.19, P=.001), and more moderate exercise (B=.25, P=.001), although the strength of the associations between using the Internet for DWPA and fruit intake and exercise was weaker in 2011 than in 2007.

Conclusions

Contrary to prior research, our population-level study did not show a pronounced gender difference in the use of the Internet for DWPA. Our results support the increasing viability of the Internet as a platform for behavior change intervention, as a growing percentage of Internet users are turning to the Internet for help with DWPA. Additionally, using the Internet for DWPA is associated with better DWPA-related health behaviors.

Effectiveness of Start to Run, a 6-week training program for novice runners, on increasing health-enhancing physical activity: a controlled study

Background

The use of the organized sports sector as a setting for health-promotion is a relatively new strategy. In the past few years, different countries have been investing resources in the organized sports sector for promoting health-enhancing physical activity. In the Netherlands, National Sports Federations were funded to develop and implement “easily accessible” sporting programs, aimed at the least active population groups. Start to Run, a 6-week training program for novice runners, developed by the Dutch Athletics Organization, is one of these programs. In this study, the effects of Start to Run on health-enhancing physical activity were investigated.

Methods

Physical activity levels of Start to Run participants were assessed by means of the Short QUestionnaire to ASsess Health-enhancing physical activity (SQUASH) at baseline, immediately after completing the program and six months after baseline. A control group, matched for age and sex, was assessed at baseline and after six months. Compliance with the Dutch physical activity guidelines was the primary outcome measure. Secondary outcome measures were the total time spent in physical activity and the time spent in each physical activity intensity category and domain. Changes in physical activity within groups were tested with paired t-tests and McNemar tests. Changes between groups were examined with multiple linear and logistic regression analyses.

Results

In the Start to Run group, the percentage of people who met the Dutch Norm for Health-enhancing Physical Activity, Fit-norm and Combi-norm increased significantly, both in the short- and longer-term. In the control group, no significant changes in physical activity were observed. When comparing results between groups, significantly more Start to Run participants compared with control group participants were meeting the Fit-norm and Combi-norm after six months. The differences in physical activity between groups in favor of the Start to Run group could be explained by an increase in the time spent in vigorous-intensity activities and sports activities.

Conclusions

Start to Run positively influences levels of health-enhancing physical activity of participants, both in the short- and longer-term. Based on these results, the use of the organized sports sector as a setting to promote health-enhancing physical activity seems promising.

Effects of aerobic conditioning on cardiovascular sympathetic response to and recovery from challenge

Exercise has widely documented cardioprotective effects, but the mechanisms behind these effects are still poorly understood. Here, we test the hypothesis that aerobic training lowers cardiovascular sympathetic responses to and speeds recovery from challenge. We conducted a randomized, controlled trial contrasting aerobic versus strength training on indices of cardiac (pre-ejection period, PEP) and vascular (low-frequency blood pressure variability, LF-BPV) sympathetic responses to and recovery from psychological and orthostatic challenge in 149 young, healthy, sedentary adults. Aerobic and strength training did not alter PEP or LF-BPV reactivity to or recovery from challenge. These findings, from a large randomized, controlled trial using an intent-to-treat design, show that moderate aerobic exercise training has no effect on PEP and LF-BPV reactivity to or recovery from psychological or orthostatic challenge. In healthy young adults, the cardioprotective effects of exercise training are unlikely to be mediated by changes in sympathetic activity.

Noncommunicable diseases: current status of major modifiable risk factors in Korea

A noncommunicable disease (NCD) is a medical condition or disease that is by definition non-infectious and non-transmissible among people. Currently, NCDs are the leading causes of death and disease burden worldwide. The four main types of NCDs, including cardiovascular disease, cancer, chronic lung disease, and diabetes, result in more than 30 million deaths annually. To reduce the burden of NCDs on global health, current public health actions stress the importance of preventing, detecting, and correcting modifiable risk factors; controlling major modifiable risk factors has been shown to effectively reduce NCD mortality. The World Health Organization's World Health Report 2002 identified tobacco use, alcohol consumption, overweight, physical inactivity, high blood pressure, and high cholesterol as the most important risk factors for NCDs. Accordingly, the present report set out to review the prevalence and trends of these modifiable risk factors in the Korean population. Over the past few decades, we observed significant risk factor modifications of improved blood pressure control and decreased smoking rate. However, hypertension and cigarette smoking remained the most contributable factors of NCDs in the Korean population. Moreover, other major modifiable risk factors show no improvement or even worsened. The current status and trends in major modifiable risk factors reinforce the importance of prevention, detection, and treatment of risk factors in reducing the burden of NCDs on individuals and society.

Association of physical inactivity with circulatory disease events and hospital treatment costs

PURPOSE

Epidemiological studies of chronic disorders need to consider more responsive outcomes, particularly those that manifest themselves across a defined population over a shorter time period, to improve our ability to detect the causes of and intervene in the global epidemics of today. We explore the use of hospital episode statistics as a candidate for this role and estimate the strength of the association of circulatory disease-related events with physical inactivity, considered here as an undesirable health behavior. SETTINGS PATIENTS AND METHODS: The primary research was set in a mid-sized city in central England. Aggregation was at output area level (comprising ~300 residents); 51 of which were included. A random sample of 761 adults was selected to obtain estimates of the mean level of physical activity within each area. Circulatory disease hospital events were recorded and aggregated by output area over a 2-year period. Hierarchical linear modeling was used to establish the strength of the association between area-level physical activity and circulatory disease events. Sex, age, and reporting quarter were included as additional individual-level explanatory variables.

RESULTS

Areas reporting greater activity were less likely (event rate ratio = 0.855; 95% confidence interval [CI]: 0.78-0.94) to have a circulatory disease event, as were females (0.593; 95% CI: 0.47-0.75). Areas with older residents (1.578; 95% CI: 1.5-1.66) and later reporting quarters (1.095; 95% CI: 1.04-1.15) were more likely to report circulatory disease events.

CONCLUSION

This study supports the use of hospital episode statistics as an outcome measure in the epidemiology of circulatory disease and reaffirms the potential importance of physical inactivity in the disease process.

The relationships between active transport to work or school and cardiovascular health or body weight: a systematic review

To systematically examine the relationships between active transport to work or school and cardiovascular health, body weight, or other health outcomes, a systematic review of the literature was conducted in September 2012 using 3 electronic databases. A total of 3887 articles were screened, 30 full text articles were retrieved, and 19 articles were identified. Two reviewers independently assessed the quality of each article. The review found that active transport to work or school was significantly associated with improved cardiovascular health and lower body weight. However, the strength of the evidence varied from weak (mental health and cancer), moderate (body weight), to strong (cardiovascular health). The evidence was limited by lack of comparability of study outcomes, weak study designs, small sample sizes, and lack of experimental studies. Further research is needed to examine the effect of active transport on health using stronger research designs, including randomized controlled trials or longitudinal studies.

A Model of Hypoxia-Reoxygenation on Isolated Adult Mouse Cardiomyocytes

The use of in vitro experimental models of hypoxia-reoxygenation (H/R) that mimic in vivo ischemia-reperfusion represents a powerful tool to investigate cardioprotective strategies against myocardial infarction. Most in vitro studies are performed using neonatal cardiac cells or immortalized embryonic cardiac cell lines which may limit the extrapolation of the results. We developed an H/R model using adult cardiomyocytes freshly isolated from mice and compared its characteristics to the in vivo ischemia-reperfusion conditions. First, cell death was assessed at different values of pH medium during hypoxia (6.2 vs 7.4) to simulate extracellular pH during in vivo ischemia. Cardiomyocyte mortality was aggravated with hypoxia under acidic pH. We next evaluated the relationship between the duration of hypoxia and cell death. Hypoxia time-dependently reduced myocyte viability (−24%, −36%, −53%, and −74% with 1, 1.5, 2, and 3 hours of hypoxia followed by 17 hours of reoxygenation, respectively). We then focused on the duration of reoxygenation as cardioprotective strategies have been reported to have different effects with short and long durations of reperfusion. We observed that cardiomyocyte mortality was increased when the duration of reoxygenation was increased from 2 h to 17 hours. Finally, we used our characterized model to investigate the cardioprotective effect of regular treadmill exercise. Myocyte viability was significantly greater in exercised when compared to sedentary mice (44% and 26%, respectively). Similarly, mice submitted to in vivo ischemia-reperfusion elicited infarct sizes reaching 27%, 43%, and 55% with 20, 30, and 45 minutes of coronary artery occlusion. In addition, infarct size was significantly reduced by exercise. In conclusion, this H/R model of cardiomyocytes freshly isolated from adult mice shows similar characteristics to the in vivo ischemia-reperfusion conditions. The comparison of in vivo and in vitro settings represents a powerful approach to investigate cardioprotective strategies and to distinguish between direct and indirect cardiomyocyte-dependent mechanisms.

A case-control study of physical activity patterns and risk of non-fatal myocardial infarction

Background

The interactive effects of different types of physical activity on cardiovascular disease (CVD) risk have not been fully considered in previous studies. We aimed to identify physical activity patterns that take into account combinations of physical activities and examine the association between derived physical activity patterns and risk of acute myocardial infarction (AMI).

Methods

We examined the relationship between physical activity patterns, identified by principal component analysis (PCA), and AMI risk in a case-control study of myocardial infarction in Costa Rica (N=4172), 1994-2004. The component scores derived from PCA and total METS were used in natural cubic spline models to assess the association between physical activity and AMI risk.

Results

Four physical activity patterns were retained from PCA that were characterized as the rest/sleep, agricultural job, light indoor activity, and manual labor job patterns. The light indoor activity and rest/sleep patterns showed an inverse linear relation (P for linearity=0.001) and a U-shaped association (P for non-linearity=0.03) with AMI risk, respectively. There was an inverse association between total activity-related energy expenditure and AMI risk but it reached a plateau at high levels of physical activity (P for non-linearity=0.01).

Conclusions

These data suggest that a light indoor activity pattern is associated with reduced AMI risk. PCA provides a new approach to investigate the relationship between physical activity and CVD risk.

Increasing physical activity of high intensity to reduce the prevalence of chronic diseases and improve public health

High incidence and prevalence of chronic diseases, increasing obesity and inactivity as well as rising health expenditure represent a set of developments that cannot be considered sustainable, and will have dire long-term consequences given the increasing proportion of elderly people in our society. Based on a review of the experiences from previous large scale population-based prevention programs and the documented effects of increased physical activity and cardiorespiratory fitness on chronic diseases and its risk factors, we argue that increased physical activity, especially vigorous physical activity, is a major way to reduce the prevalence of chronic diseases and improve public health. We conclude that a coordinated population-based intervention program for improved health through increased physical activity in the entire population, with a special focus on high intensity exercise, urgently needs to be implemented nationally and internationally.

The association between leisure time physical activity and coronary heart disease among men with different physical work demands: a prospective cohort study

The interplay of occupational and leisure time physical activity (LTPA) in affecting cardiovascular health is subject to debate. This study aimed to examine the independent and interacting associations of leisure time and occupational physical activity (OPA) with the incidence of coronary events within the BELSTRESS cohort. The study included 14,337 middle-aged men free from coronary heart disease at baseline. Standardized questionnaires and clinical examinations were used to assess socio-demographic factors, level of physical activity, job strain and classical coronary risk factors. The incidence of clinical coronary events was monitored during a mean follow-up time of 3.15 years. Results demonstrated overall a beneficial relation of LTPA and an adverse relation of physical work demands with cardiovascular health. However, an interaction effect between both physical activity types was observed, showing that men with high physical job demands who also engaged in physical activity during leisure time had an almost four times increased incidence of coronary events after adjusting for socio-demographic and classical coronary risk factors (HR 3.82; 95% CI 1.41-10.36). Stratified analyses revealed that moderate to high physical activity during leisure time was associated with a 60% reduced incidence rate of coronary events in men with low OPA (age adjusted HR 0.40; 95% CI 0.21-0.76), while this protective association was not observed in workers being exposed to high physical work demands (age adjusted HR 1.67; 95% CI 0.63-4.48). These findings suggest that recommendations regarding LTPA should be tailored according to the level of occupational physical activity.

Physical activity, cardiorespiratory fitness, and exercise training in primary and secondary coronary prevention

Substantial data have established that higher levels of physical activity (PA), participating in exercise training (ET), and higher overall cardiorespiratory fitness (CRF) provide considerable protection in the primary and secondary prevention of coronary heart disease (CHD). This review surveys data from epidemiological and prospective ET studies supporting the favorable impact of PA, ET, and CRF in primary CHD prevention. Clearly, cardiac rehabilitation and ET (CRET) programs have been underutilized for patients with CHD, particularly considering the effect of CRET on CHD risk factors, including CRF, obesity indices, fat distribution, plasma lipids, inflammation, and psychological distress, as well as overall morbidity and mortality. These data strongly support the routine referral of patients with CHD to CRET programs and that patients should be vigorously encouraged to attend CRET following major CHD events.

Job strain as a risk factor for leisure-time physical inactivity: an individual-participant meta-analysis of up to 170,000 men and women: the IPD-Work Consortium

Unfavorable work characteristics, such as low job control and too high or too low job demands, have been suggested to increase the likelihood of physical inactivity during leisure time, but this has not been verified in large-scale studies. The authors combined individual-level data from 14 European cohort studies (baseline years from 1985–1988 to 2006–2008) to examine the association between unfavorable work characteristics and leisure-time physical inactivity in a total of 170,162 employees (50% women; mean age, 43.5 years). Of these employees, 56,735 were reexamined after 2–9 years. In cross-sectional analyses, the odds for physical inactivity were 26% higher (odds ratio = 1.26, 95% confidence interval: 1.15, 1.38) for employees with high-strain jobs (low control/high demands) and 21% higher (odds ratio = 1.21, 95% confidence interval: 1.11, 1.31) for those with passive jobs (low control/low demands) compared with employees in low-strain jobs (high control/low demands). In prospective analyses restricted to physically active participants, the odds of becoming physically inactive during follow-up were 21% and 20% higher for those with high-strain (odds ratio = 1.21, 95% confidence interval: 1.11, 1.32) and passive (odds ratio = 1.20, 95% confidence interval: 1.11, 1.30) jobs at baseline. These data suggest that unfavorable work characteristics may have a spillover effect on leisure-time physical activity.

Regular treadmill exercise restores cardioprotective signaling pathways in obese mice independently from improvement in associated co-morbidities

Obesity is a major health issue that impedes the ability of preconditioning and postconditioning to protect the myocardium against infarction secondary to dysregulation of kinase signaling pathways. Moreover, exercise decreases cardiovascular mortality in obese patients but the mechanism remains to be established. Wild-type (WT) and obese (ob/ob) mice were assigned to sedentary conditions or regular treadmill exercise (1h/day, 5 days/7, 4 weeks, 4° slope, 10-30 cm/s) and underwent 30 min of coronary artery occlusion followed by 24h of reperfusion for infarct size measurement. In WT, exercise reduced infarct size by 60% and increased phosphorylation of kinases such as Akt, ERK 1/2, p70S6K, AMPK and GSK3β. Importantly, the level of corresponding phosphatases PTEN, MKP-3 and PP2C was decreased. Calcium concentration inducing the opening of mitochondrial permeability transition pore (mPTP) was increased by exercise. In ob/ob, regular exercise induced a robust cardioprotection by reducing infarct size (-67%), increasing kinase phosphorylation, decreasing phosphatase levels and improving the resistance to mPTP opening. However exercise did not modify hyperglycemia, hypercholesterolemia, hyperinsulinemia, fat mass and body weight in obese mice. In conclusion, regular exercise induces cardioprotection against myocardial infarction despite obesity and restores pro-survival signaling pathways with simultaneous increase in kinase phosphorylations, decreased levels of phosphatases and increased resistance of mPTP opening, independently from improvement in associated co-morbidities.

Physical activity patterns in the French 18-74-year-old population: French Nutrition and Health Survey (Etude Nationale Nutrition Santé, ENNS) 2006-2007

OBJECTIVE

To describe detailed physical activity and sedentary behaviour in French adults across physical activity categories.

DESIGN

The French Nutrition and Health Survey (Etude Nationale Nutrition Santé, ENNS), conducted in 2006-2007, was a national cross-sectional survey based on three-stage random sampling. The International Physical Activity Questionnaire (IPAQ) was used to classify participants into three physical activity categories. Time spent in a sitting position and time spent in front of a screen were used as markers of sedentary behaviour.

SETTING

France.

SUBJECTS

Adults (n 2971) aged 18 to 74 years were included.

RESULTS

Overall, 29·5 % of men and 23·6 % of women were classified into the high-IPAQ category, while 36·1 % of men and 37·5 % of women were in the low-IPAQ category. For each intensity level of physical activity (vigorous intensity, moderate intensity or walking), the number of active days per week decreased from the high- to the low-IPAQ category and daily duration of physical activity was longer in the high-IPAQ category than in the other two categories; 6 % of adults declared neither vigorous nor moderate nor walking activities.

CONCLUSIONS

For most adults in the low-IPAQ category, an increasing number of active days per week would be sufficient to attain the moderate-IPAQ category. This should be taken into account in public health initiatives aimed at promoting physical activity.

Effect of a Web-based intervention to promote physical activity and improve health among physically inactive adults: a population-based randomized controlled trial

Background

Many people in Western countries do not follow public health physical activity (PA) recommendations. Web-based interventions provide cost- and time-efficient means of delivering individually targeted lifestyle modification at a population level.

Objective

To examine whether access to a website with individually tailored feedback and suggestions on how to increase PA led to improved PA, anthropometrics, and health measurements.

Methods

Physically inactive adults (n = 12,287) participating in a nationwide eHealth survey and health examination in Denmark were randomly assigned to either an intervention (website) (n = 6055) or a no-intervention control group (n = 6232) in 2008. The intervention website was founded on the theories of stages of change and of planned behavior and, apart from a forum page where a physiotherapist answered questions about PA and training, was fully automated. After 3 and again after 6 months we emailed participants invitations to answer a Web-based follow-up questionnaire, which included the long version of the International Physical Activity Questionnaire. A subgroup of participants (n = 1190) were invited to a follow-up health examination at 3 months.

Results

Less than 22.0% (694/3156) of the participants logged on to the website once and only 7.0% (222/3159) logged on frequently. We found no difference in PA level between the website and control groups at 3- and 6-month follow-ups. By dividing participants into three groups according to use of the intervention website, we found a significant difference in total and leisure-time PA in the website group. The follow-up health examination showed no significant reductions in body mass index, waist circumference, body fat percentage, and blood pressure, or improvements in arm strength and aerobic fitness in the website group.

Conclusions

Based on our findings, we suggest that active users of a Web-based PA intervention can improve their level of PA. However, for unmotivated users, single-tailored feedback may be too brief. Future research should focus on developing more sophisticated interventions with the potential to reach both motivated and unmotivated sedentary individuals.

Trial Registration

Clinicaltrials.gov NCT01295203; http://clinicaltrials.gov/ct2/show/NCT01295203 (Archived by WebCite at http://www.webcitation.org/6B7HDMqiQ)

Physical activity in relation to cardiac risk markers in secondary prevention of coronary artery disease

BACKGROUND

The relationship between physical activity and cardiac risk markers in secondary prevention for patients with coronary artery disease (CAD) is uncertain. The aims of the study were therefore to examine the level of physical activity in patients with CAD, and to investigate the association between physical activity and cardiac risk markers.

METHODS

In total, 332 patients, mean age, 65 ± 9.1 years, diagnosed with CAD at a university hospital were included in the study 6 months after their cardiac event. Physical activity was measured with a pedometer (steps/day) and two questionnaires. Investigation of cardiac risk markers included serum lipids, oral glucose-tolerance test, twenty-four hour blood pressure and heart rate monitoring, smoking, body-mass index (BMI), waist-hip ratio, and muscle endurance. The study had a cross-sectional design.

RESULTS

The patients performed a median of 7,027 steps/day. After adjustment for confounders, statistically significant correlations between steps/day and risk markers were found with regard to; high-density lipoprotein cholesterol (HDL-C) (r=0.19, p<0.001), muscle endurance measures (r ranging from 0.19 to 0.25, p=0.001 or less) triglycerides (r=-0.19, p<0.001), glucose-tolerance (r=-0.23, p<0.001), BMI (r=-0.21, p<0.001), 24-h heart rate recording during night (r=-0.17, p=0.004), and average 24-h heart rate (r=-0.13, p=0.02).

CONCLUSIONS

A relatively high level of physical activity was found among patients with CAD. There was a weak, but significant, association between pedometer steps/day and HDL-C, muscle endurance, triglycerides, glucose-tolerance, BMI and 24-h heart rate, indicating potential positive effects of physical activity on these parameters. However, before clinical implications can be formed, more confirmatory data are needed.

The association of leisure-time physical activity and active commuting with measures of socioeconomic position in a multiethnic population living in the Netherlands: results from the cross-sectional SUNSET study

BACKGROUND

In most European origin populations measures of socioeconomic position are positively associated with leisure time physical activity (LTPA), this is unclear for active commuting. In addition, these associations have scarcely been studied in ethnic minority groups, who often have a high cardiovascular disease risk. Because of the expected public health potential, we assessed the relationship of active commuting and LTPA with measures of socioeconomic position across two large ethnic minority groups in the Netherlands as compared to the European-Dutch population.

METHODS

We included South Asian-Surinamese (n = 370), African-Surinamese (n = 689), and European-Dutch (n = 567) from the cross-sectional population-based SUNSET study (2001-2003). Active commuting and LTPA were assessed by the SQUASH physical activity questionnaire and calculated in square-root-transformed metabolic equivalents of task-hours/week (SQRTMET). Socioeconomic position was indicated by level of education (low/high) and occupational class (low/high). We used age-adjusted linear regression models to assess the association between physical activity and socioeconomic position.

RESULTS

Compared to the European-Dutch men, South Asian-Surinamese men engaged in lower levels of commuting activity and LTPA, and South Asian-Surinamese women engaged in lower levels of LTPA than their European-Dutch counterparts. Differences between the African Surinamese and the European-Dutch were small. We observed a positive gradient in active commuting activity for education in European-Dutch men (beta high education was 0.93, 95%CI: 0.45-1.40 SQRTMET higher versus low education), in South Asian-Surinamese men (beta: 0.56, 0.19-0.92), but not in African-Surinamese men (-0.06, -0.45-0.33, p for ethnicity-interaction = 0.002). In women we observed a positive gradient in active commuting activity and occupational class in European-Dutch women, and less strongly in South Asian-Surinamese and African-Surinamese women (p for ethnicity-interaction = 0.02). For LTPA and socioeconomic position, we observed no statistically significant interaction by ethnicity.

CONCLUSIONS

The positive gradient for socioeconomic position observed in European-Dutch was less strong, in particular for active commuting, among the South Asian-Surinamese and the African-Surinamese. This indicates that the typical focus on physical activity interventions in lower socioeconomic groups could work for European-Dutch populations, but this strategy may not be entirely applicable in the ethnic minority groups.

Physical activity levels six months after a randomised controlled physical activity intervention for Pakistani immigrant men living in Norway

Background

To our knowledge, no studies have aimed at improving the PA level in south Asian immigrant men residing in Western countries, and few studies have considered the relevance of SCT constructs to the PA behaviour of this group in the long term. The observed low physical activity (PA) level among south Asian immigrants in Western countries may partly explain the high prevalence of cardiovascular diseases (CVD) and type 2 diabetes (T2D) in this group. We have shown previously in a randomised controlled trial, the Physical Activity and Minority Health study (PAMH) that a social cognitive based intervention can beneficially influence PA level and subsequently reduce waist circumference and insulin resistance in the short-term. In an extended follow-up of the PAMH study: we aimed 1) to determine if the intervention produced long-term positive effects on PA level six months after intervention (follow-up 2 (FU2)), and 2) to identify the social cognitive mediators of any intervention effects.

Methods

Physically inactive Pakistani immigrant men (n = 150) who were free of CVD and T2D were randomly assigned to a five months PA intervention or a control group. Six months after the intervention ended, we telephoned all those who attended FU1 and invited them for a second follow-up test (FU2) (n = 133). PA was measured using ActiGraph accelerometers. Statistical differences between groups were determined by use of ANCOVA.

Results

Significant differences (baseline to FU2) between the groups were found for all PA variables (e.g., total PA level, sedentary time, PA intensity). Support from family and outcome expectancies increased more in the intervention group compared with the control group. Self-efficacy did not differ significantly between groups.

Conclusions

Our results show that a multi component PA programme can increase PA over the short and long term in a group of immigrant Pakistani men. However, we could not identify the factors that mediated these changes in PA.

Protocol ID

07112001326, NCT ID: NCT00539903

Impairment of activities of daily living and incident heart failure in community-dwelling older adults

AIMS

Instrumental activities of daily living (IADLs) are tasks that are necessary for independent community living. These tasks often require intact physical and cognitive function, the impairment of which may adversely affect health in older adults. In the current study, we examined the association between IADL impairment and incident heart failure (HF) in community-dwelling older adults.

METHODS AND RESULTS

Of the 5795 community-dwelling adults, aged ≥65 years, in the Cardiovascular Health Study, 5511 had data on baseline IADL and were free of prevalent HF. Of these, 1333 (24%) had baseline IADL impairment, defined as self-reported difficulty with one or more of the following tasks: using the telephone, preparing food, performing light and heavy housework, managing finances, and shopping. Propensity scores for IADL impairment, estimated for each of the 5511 participants, were used to assemble a cohort of 1038 pairs of participants with and without IADL impairment who were balanced on 42 baseline characteristics. Centrally adjudicated incident HF occurred in 26% and 21% of matched participants with and without IADL impairment, respectively, during >12 years of follow-up [matched hazard ratio (HR) 1.33; 95% confidence interval (CI) 1.11-1.59; P = 0.002]. Unadjusted and multivariable-adjusted HRs for incident HF before matching were 1.77 (95% CI 1.56-2.01; P < 0.001) and 1.33 (95% CI 1.15-1.54; P < 0.001), respectively. IADL impairment was also associated with all-cause mortality (matched HR 1.19; 95% CI 1.06-1.34; P = 0.004).

CONCLUSION

Among community-dwelling older adults free of baseline HF, IADL impairment is a strong and independent predictor of incident HF and mortality.

Physical activity and risk of cardiovascular disease--a meta-analysis of prospective cohort studies

In order to update and improve available evidence on associations of physical activity (PA) with cardiovascular disease (CVD) by applying meta-analytic random effects modeling to data from prospective cohort studies, using high quality criteria of study selection, we searched the PubMed database from January 1980 to December 2010 for prospective cohort studies of PA and incident CVD, distinguishing occupational PA and leisure time PA, coronary heart disease (CHD) and stroke, respectively. Inclusion criteria were peer-reviewed English papers with original data, studies with large sample size (n ≥ 1,000) and substantial follow-up (≥ 5 years), available data on major confounders and on estimates of relative risk (RR) or hazard ratio (HR), with 95% confidence intervals (CI). We included 21 prospective studies in the overall analysis, with a sample size of more than 650,000 adults who were initially free from CVD, and with some 20,000 incident cases documented during follow-up. Among men, RR of overall CVD in the group with the high level of leisure time PA was 0.76 (95% CI 0.70-0.82, p < 0.001), compared to the reference group with low leisure time PA, with obvious dose-response relationship. A similar effect was observed among women (RR = 0.73, 95% CI 0.68-0.78, p < 0.001). A strong protective effect of occupational PA was observed for moderate level in both men (RR = 0.89, 95% CI 0.82-0.97, p = 0.008) and women (RR = 0.83, 95% CI 0.67-1.03, p = 0.089). No publication bias was observed. Our findings suggest that high level of leisure time PA and moderate level of occupational PA have a beneficial effect on cardiovascular health by reducing the overall risk of incident coronary heart disease and stroke among men and women by 20 to 30 percent and 10 to 20 percent, respectively. This evidence from high quality studies supports efforts of primary and secondary prevention of CVD in economically advanced as well as in rapidly developing countries.

Importance of characteristics and modalities of physical activity and exercise in defining the benefits to cardiovascular health within the general population: recommendations from the EACPR (Part I)

Over the last decades, more and more evidence is accumulated that physical activity (PA) and exercise interventions are essential components in primary and secondary prevention for cardiovascular disease. However, it is less clear whether and which type of PA and exercise intervention (aerobic exercise, dynamic resistive exercise, or both) or characteristic of exercise (frequency, intensity, time or duration, and volume) would yield more benefit in achieving cardiovascular health. The present paper, as the first of a series of three, will make specific recommendations on the importance of these characteristics for cardiovascular health in the population at large. The guidance offered in this series of papers is aimed at medical doctors, health practitioners, kinesiologists, physiotherapists and exercise physiologists, politicians, public health policy makers, and the individual member of the public. Based on previous and the current literature, recommendations from the European Association on Cardiovascular Prevention and Rehabilitation are formulated regarding type, volume, and intensity of PA and exercise.

Impact of lifestyle-related factors on all-cause and cause-specific mortality in patients with type 2 diabetes: the Taichung Diabetes Study

OBJECTIVE

To examine whether combined lifestyle behaviors have an impact on all-cause and cause-specific mortality in patients aged 30-94 years with type 2 diabetes (T2DM).

RESEARCH DESIGN AND METHODS

Participants included 5,686 patients >30 years old with T2DM who were enrolled in a Diabetes Care Management Program at a medical center in central Taiwan before 2007. Lifestyle behaviors consisted of smoking, alcohol drinking, physical inactivity, and carbohydrate intake. The main outcomes were all-cause and cause-specific mortality. Cox proportional hazards models were used to examine the association between combined lifestyle behaviors and mortality.

RESULTS

The mortality rate among men was 24.10 per 1,000 person-years, and that among women was 17.25 per 1,000 person-years. After adjusting for the traditional risk factors, we found that combined lifestyle behavior was independently associated with all-cause mortality and mortality due to diabetes, cardiovascular disease, and cancer. Patients with three or more points were at a 3.50-fold greater risk of all-cause mortality (95% CI 2.06-5.96) and a 4.94-fold (1.62-15.06), 4.24-fold (1.20-14.95), and 1.31-fold (0.39-4.41) greater risk of diabetes-specific, CVD-specific, and cancer-specific mortality, respectively, compared with patients with zero points. Among these associations, the combined lifestyle behavior was not significantly associated with cancer mortality.

CONCLUSIONS

Combined lifestyle behavior is a strong predictor of all-cause and cause-specific mortality in patients with T2DM.

[The coronary patient six months after cardiac rehabilitation: rehabilitation evaluation research (RER study)]

AIMS OF THE STUDY

The aims of the study are to elaborate and test, in a coronary population admitted in a cardiac rehabilitation (CR) department, an evaluative method 6 months after a cardiac rehabilitation programme, with emphasis on modified cardiac risk factors.

PATIENTS AND METHODS

Every coronary patient admitted in the CR department in Machecoul between 2007 October and 2009 October, who's home were not over 50 km far away and without mental inability, were included. At the start of the programme, he was suggested to complete the training course by a phone interview at 3 months and a multidisciplinary consult at 6 months. It used dietary and physical activity questionnaires, and a 6-minute walk test (6mnWT).

RESULTS

Two hundred and two patients were included (mean age 63,4 ± 10 years, 93% men), 17% after an acute coronary syndrome, 23% after angioplasty and 75% after coronary artery bypass graft. The cardioprotective dietary score increased from 7.8 ± 4.3 to 12.7 ± 3 (on a scale from-17 to+19) and the physical activity score from 15.4 ± 7.7 to 19.5 ± 4.8 (on a scale from 5 to 40). The 6mnWT increased in CR (from 431 ± 90m to 511 ± 91m) and was maintained at 6 months (513 ± 88m). The European recommendation goals were achieved by 76% of patients for LDL (<1g/L), 64% for blood pressure (<140/90), 82% for a BMI less than 30 and 36% a BMI less than 25, 67% central obesity (<102cm by men and 88 cm by women) and 82% for no smoking. Four non-fatal cardiac events and seven vascular events were reported by a mean delay of 190 ± 30 days.

CONCLUSION

A six monthly evaluation of CR programme can be used in a cardiac rehabilitation department routinely activity.

Dose response between physical activity and risk of coronary heart disease: a meta-analysis

BACKGROUND

No reviews have quantified the specific amounts of physical activity required for lower risks of coronary heart disease when assessing the dose-response relation. Instead, previous reviews have used qualitative estimates such as low, moderate, and high physical activity.

METHODS AND RESULTS

We performed an aggregate data meta-analysis of epidemiological studies investigating physical activity and primary prevention of CHD. We included prospective cohort studies published in English since 1995. After reviewing 3194 abstracts, we included 33 studies. We used random-effects generalized least squares spline models for trend estimation to derive pooled dose-response estimates. Among the 33 studies, 9 allowed quantitative estimates of leisure-time physical activity. Individuals who engaged in the equivalent of 150 min/wk of moderate-intensity leisure-time physical activity (minimum amount, 2008 U.S. federal guidelines) had a 14% lower coronary heart disease risk (relative risk, 0.86; 95% confidence interval, 0.77 to 0.96) compared with those reporting no leisure-time physical activity. Those engaging in the equivalent of 300 min/wk of moderate-intensity leisure-time physical activity (2008 U.S. federal guidelines for additional benefits) had a 20% (relative risk, 0.80; 95% confidence interval, 0.74 to 0.88) lower risk. At higher levels of physical activity, relative risks were modestly lower. People who were physically active at levels lower than the minimum recommended amount also had significantly lower risk of coronary heart disease. There was a significant interaction by sex (P=0.03); the association was stronger among women than men.

CONCLUSIONS

These findings provide quantitative data supporting US physical activity guidelines that stipulate that "some physical activity is better than none" and "additional benefits occur with more physical activity."

Social support and leisure-time physical activity: longitudinal evidence from the Brazilian Pró-Saúde cohort study

Background

Although social support has been observed to exert a beneficial influence on leisure-time physical activity (LTPA), multidimensional approaches examining social support and prospective evidence of its importance are scarce. The purpose of this study was to investigate how four dimensions of social support affect LTPA engagement, maintenance, type, and time spent by adults during a two-year follow-up.

Methods

This paper reports on a longitudinal study of 3,253 non-faculty public employees at a university in Rio de Janeiro (the Pró-Saúde study). LTPA was evaluated using a dichotomous question with a two-week reference period, and further questions concerning LTPA type (individual or group) and time spent on the activity. Social support was measured by the Medical Outcomes Study Social Support Scale (MOS-SSS). To assess the association between social support and LTPA, two different statistical models were used: binary and multinomial logistic regression models for dichotomous and polytomous outcomes, respectively. Models were adjusted separately for those who began LTPA in the middle of the follow up (engagement group) and for those who had maintained LTPA since the beginning of the follow up (maintenance group).

Results

After adjusting for confounders, statistically significant associations (p < 0.05) between dimensions of social support and group LTPA were found in the engagement group. Also, the emotional/information dimension was associated with time spent on LTPA (OR = 2.01; 95% CI 1.2-3.9). In the maintenance group, material support was associated with group LTPA (OR = 1.80; 95% CI; 1.1-3.1) and the positive social interaction dimension was associated with time spent on LTPA (OR = 1.65; 95% CI; 1.1-2.7).

Conclusions

All dimensions of social support influenced LTPA type or the time spent on the activity. However, our findings suggest that social support is more important in engagement than in maintenance. This finding is important, because it suggests that maintenance of LTPA must be associated with other factors beyond the individual's level of social support, such as a suitable environment and social/health policies directed towards the practice of LTPA.

Physical activity and 5-year changes in physical performance tests and bone mineral density in postmenopausal women: the Yokogoshi Study

OBJECTIVE

The effect of physical activity on musculoskeletal health in older adults is not completely understood. The aim of this study was to determine the relationship between physical activity and 5-year changes in physical performance tests and bone mineral density (BMD) in postmenopausal women.

STUDY DESIGN

The design was a 5-year cohort study.

MAIN OUTCOME MEASURES

Subjects were 507 women (55-74 years old) living in a rural community in Japan. Physical activity assessed included housework, farm work, and moderate leisure-time physical activity within the previous week. Measurements at baseline included handgrip strength, walking time (timed "Up & Go" test) and BMD of the femoral neck and vertebrae. Five-year changes in these measures (outcome variables) were compared among groups with different levels of physical activity by analysis of covariance.

RESULTS

Women who did not do housework performed worse in changes in handgrip strength (difference=2.22 kg, P=0.0201) and worse in changes in the walking time (difference=0.54 s, P=0.0072) than those who did housework alone. Women who spent at least 9h per week (median=24) doing farm work performed better in changes in handgrip strength (difference=0.28 kg, P=0.0334), but worse in changes in the walking time (difference=0.66 s, P<0.0001) than those who did not do farm work. However, leisure-time activity was not associated with changes in any outcome variable, and none of the physical activities predicted BMD changes.

CONCLUSIONS

Engaging in housework and farm work are determinants of physical function in postmenopausal women, which may help them maintain independence in daily living.

Effect of exercise training on vascular endothelial function in patients with stable coronary artery disease: a randomized controlled trial

Background: We aim to investigate the effect of exercise training on endothelial function and exercise capacity in patients with coronary artery disease.

Methods and results: A randomized, controlled trial was conducted to determine the effects of an 8-week exercise training programme ( n = 32) vs. controls ( n = 32) on brachial flow-mediated dilation (FMD) in patients with stable CAD. After 8 weeks, patients received exercise training had significant improvements in FMD (1.84%, p = 0.002) and exercise capacity (2.04 metabolic equivalents, p < 0.001) compared with controls. The change in FMD correlated inversely with baseline FMD ( r = −0.41, p = 0.001) and positively with the increase in exercise capacity ( r = 0.35, p = 0.005). After adjusting for confounders, every 1 metabolic equivalent increase in exercise capacity was associated with 0.55% increase in FMD. Furthermore, patients received exercise training had significantly increased high-density lipoprotein cholesterol and decreased diastolic blood pressure and resting heart rate compared with controls. However, exercise training did not alter high-sensitivity C-reactive protein, oxidative stress measured as superoxide dismutase and 8-isoprostane, and CD34/KDR + endothelial progenitor cell count. Subgroup analysis showed that FMD was significantly improved only in CAD patients with baseline low exercise capacity (<median value of 7.65 metabolic equivalents, p = 0.004) but not in those with normal exercise capacity.

Conclusion: Exercise training improved FMD and exercise capacity in stable CAD patients independent of the changes in inflammation, oxidative stress, or endothelial progenitor cells. The beneficial effects of exercise training on FMD and exercise capacity are inter-related, and more pronounced in those with baseline impaired exercise capacity.