Ethnic Minority Children’s Active Commuting to School and Association with Physical Activity and Pedestrian Safety Behaviors

Background: Children's active commuting to school, i.e. walking or cycling to school, was associated with greater moderate-to-vigorous physical activity, although studies among ethnic minorities are sparse. Objectives: Among a low-income, ethnic minority sample of fourth grade students from eight public schools, we examined (1) correlates of active commuting to school and (2) the relationship between active commuting to school and moderate-to-vigorous physical activity. Methods: We conducted a cross-sectional analysis of baseline measurements from a sample of participants (n=149) aged 9-12 years from a walk to school intervention study in Houston, Texas. The primary outcome was the weekly rate of active commuting to school. Daily moderate-to-vigorous physical activity, measured by accelerometers, was a secondary outcome. Child self-efficacy (alpha=0.75), parent self-efficacy (alpha=0.88), and parent outcome expectations (alpha=0.78) were independent variables. Participant characteristics (age, gender, race/ethnicity, distance from home to school, acculturation, and BMI percentile) were independent sociodemographic variables. We used mixed-model regression analyses to account for clustering by school and a stepwise procedure with backward elimination of non-significant interactions and covariates to identify significant moderators and predictors. School-level observations of student pedestrians were assessed and compared using chi-square tests of independence. Results: Among our sample, which was 61.7% Latino, the overall rate of active commuting to school was 43%. In the mixed model for active commuting to school, parent self-efficacy (std. beta = 0.18, p=0.018) and age (std. beta = 0.18, p=0.018) were positively related. Latino students had lower rates of active commuting to school than non-Latinos ( 16.5%, p=0.040). Distance from home to school was inversely related to active commuting to school (std. beta = 0.29, p<0.001). In the mixed model for moderate-to-vigorous physical activity, active commuting to school was positively associated (std. beta = 0.31, p <0.001). Among the Latino subsample, child acculturation was negatively associated with active commuting to school (std. beta = -0.23, p=0.01). With regard to school-level pedestrian safety observations, 37% of students stopped at the curb and 2.6% looked left-right-left before crossing the street. Conclusion: Although still below national goals, the rate of active commuting was relatively high, while the rate of some pedestrian safety behaviors was low among this low-income, ethnic minority population. Programs and policies to encourage safe active commuting to school are warranted and should consider the influence of parents, acculturation, and ethnicity.

Physical activity and survival after a first myocardial infarction: The Corpus Christi Heart Project

Previous studies have demonstrated that habitual physical activity is associated with a reduced risk of incident coronary heart disease (CHD). However, the role of physical activity in lowering the risk of all-cause mortality, CHD mortality, reinfarction, or receipt of a revascularization procedure after a first myocardial infarction (MI) remains unresolved, particularly in minority populations. To investigate the associations between physical activity and risk of all-cause mortality, CHD mortality, reinfarction, and receipt of a revascularization procedure, this study was conducted among Mexican-American and non-Hispanic white women and men who survived a first MI. The Corpus Christi Heart Project, a population-based cardiovascular surveillance study, provide data which included vital status, survival time, medical history, CHD risk factor information, including level of physical activity among Mexican-American and non-Hispanic white adults who had experienced a first MI between May, 1988 and April, 1990. MI patients were interviewed at baseline and annually thereafter until their death or through May, 1995. A categorical variable was created to reflect change in level of physical activity following the first MI; categories included (1) sedentary with no change, (2) decreased activity, (3) increased activity, and (4) moderate activity with no change (the referent group). Proportional hazards regression analyses were used to assess the relationship of level of physical activity and risk of death, reinfarction, or receipt of a revascularization procedure adjusting for age, sex, ethnicity, severity of MI, and CHD risk factor status. Over a 7-year follow-up period, the relative risk (95% confidence intervals) of all-cause mortality was 4.67 (2.27, 9.60) for the sedentary-no change group, 2.33 (0.96, 5.67) for the decreased activity group, and 0.52 (0.11, 2.41) for the increased activity group. The relative risk of CHD mortality was 6.92 (2.05, 23.34) for the sedentary-no change group, 2.40 (0.55, 10.51) for the decreased activity group, and 1.58 (0.26, 9.65) for the increased activity group. The relative risk for reinfarction was 2.50 (1.52, 4.10) for the sedentary-no change group, 2.26 (1.24, 4.12) for the decreased activity group, and 0.52 (0.21, 1.32) for the increased activity group. Finally, the relative risk for receipt of a revascularization procedure was 0.65 (0.39, 1.07) for the sedentary-no change group, 0.45 (0.22, 0.92) for the decreased activity group, and 1.01 (0.51, 2.02) for the increased activity group. No interactions were observed for ethnicity or severity of first MI. These results are consistent with the hypothesis that moderate physical activity is independently associated with a lower risk of all-cause mortality, CHD mortality, and reinfarction, but not revascularization, among Mexican-American and non-Hispanic white, female and male, first MI patients. These results also support the current recommendation that physical activity plays an important role in the secondary prevention of CHD. ^

Comparison of telomere length in black and white teachers from South Africa: the sympathetic activity and ambulatory blood pressure in Africans study

OBJECTIVE Telomere length is a marker of biological aging that has been linked to cardiovascular disease risk. The black South African population is witnessing a tremendous increase in the prevalence of cardiovascular disease, part of which might be explained through urbanization. We compared telomere length between black South Africans and white South Africans and examined which biological and psychosocial variables played a role in ethnic difference in telomere length. METHODS We measured leukocyte telomere length in 161 black South African teachers and 180 white South African teachers aged 23 to 66 years without a history of atherothrombotic vascular disease. Age, sex, years having lived in the area, human immunodeficiency virus (HIV) infection, hypertension, body mass index, dyslipidemia, hemoglobin A1c, C-reactive protein, smoking, physical activity, alcohol abuse, depressive symptoms, psychological distress, and work stress were considered as covariates. RESULTS Black participants had shorter (median, interquartile range) relative telomere length (0.79, 0.70-0.95) than did white participants (1.06, 0.87-1.21; p < .001), and this difference changed very little after adjusting for covariates. In fully adjusted models, age (p < .001), male sex (p = .011), and HIV positive status (p = .023) were associated with shorter telomere length. Ethnicity did not significantly interact with any covariates in determining telomere length, including psychosocial characteristics. CONCLUSIONS Black South Africans showed markedly shorter telomeres than did white South African counterparts. Age, male sex, and HIV status were associated with shorter telomere length. No interactions between ethnicity and biomedical or psychosocial factors were found. Ethnic difference in telomere length might primarily be explained by genetic factors.

Physical activity and liver diseases

Regular physical activity beneficially impacts the risk of onset and progression of several chronic diseases. However, research regarding the effects of exercising on chronic liver diseases is relatively recent. Most authors focused on non-alcoholic fatty liver disease (NAFLD), in which increasing clinical and experimental data indicate that skeletal muscle cross-talking to the adipose tissue and the liver regulates intrahepatic fat storage. In this setting physical activity is considered required in combination with calories restriction to allow an effective decrease of intrahepatic lipid component, and despite that evidence is not conclusive, some studies suggest that vigorous activity might be more beneficial than moderate activity to improve NAFLD/NASH. Evidence regarding the effects of exercise on the risk of hepatocellular carcinoma is scarce; some epidemiological studies indicate a lower risk in patients regularly and vigorously exercising. In compensated cirrhosis exercise acutely increases portal pressure, but in longer term it has been proved safe and probably beneficial. Decreased aerobic capacity (VO2) correlates with mortality in patients with decompensated cirrhosis, who are almost invariably sarcopenic. In these patients VO2 is improved by physical activity, which might also reduce the risk of hepatic encephalopathy through an increase in skeletal muscle mass. In solid organ transplantation recipients exercise is able to improve lean mass, muscle strength and as a consequence, aerobic capacity. Few data exist in liver transplant recipients, in whom exercise should be object of future studies given its high potential of providing long-term beneficial effects. Despite evidence is far from complete, physical activity should be seen as an important part of the management of patients with liver disease in order to improve their clinical outcome. This article is protected by copyright. All rights reserved.

Physician's adherence to CDC standards for physical activity counseling of older women in a cardiology practice in Texas---An exploratory study

Physical activity is an important health-promoting behavior to prevent and control chronic disease. Interventions to increase physical activity are vitally needed. Women are not meeting the recommended goals for physical activity - a behavior that has been shown to effectively reduce the incidence of chronic disease and the medical costs associated with treating it. Among many factors predicting physical activity and the different forms of interventions that have been applied, physician counseling is one potentially cost-effective approach that may produce at least modest effects on women's behavior. The Centers for Disease Control and Prevention has published standards for physician counseling of patients regarding physical activity. This study used a short questionnaire to assess the degree to which a group practice of cardiology physicians in Texas queried and discussed physical activity recommendations to older women that they treat and whether they are meeting the physical activity counseling goals of the Centers for Disease Control and Prevention. The majority of this group of physicians counseled patients without benefit of exploring patient behavior. Although these physicians "agreed" that physical activity delayed or prevented disease, the outcome suggests that low self-efficacy hampered efforts to counsel older women on this. Physicians' perceptions that counseling may be ineffective could explain the lower rate of physical activity counseling that does not meet the goals of the Centers for Disease Control and Prevention. ^

Marketing physical activity and healthy eating: A literature review of recent social marketing campaigns and development of a social marketing plan for the CATCH program

Background. This culminating experience project was inspired by an independent study conducted at The University of Texas School of Public Health with Dr. Andrew Springer, DrPH, who works on the evaluation of the Coordinated Approach to Child Health (CATCH) program in Travis County, Texas. It was indicated that a social marketing plan could enhance current efforts for the CATCH program. The aims of the project were to (1) review and synthesize literature on social marketing, with a specific focus on diet, physical activity, and obesity prevention; and (2) apply the gained knowledge toward a practical solution – a social marketing plan for the CATCH program.^ Methods. The literature review aimed to answer the following questions: (1) What audiences (ethnic and age groups), settings, health behaviors, and behavioral science theories have been used in social marketing campaigns? (2) What features of social marketing were used (e.g. formative research, segmentation, and the marketing mix - including promotional strategies and communication channels)? (3) What were the outcomes of the social marketing campaigns? The search aimed to identify studies that met the following inclusion criteria: (a) The study explicitly stated that social marketing was used; (b) The intervention promoted physical activity and/or healthy eating; (c) The population was children, adolescents, young adults, and/or parents; (d) Results of the intervention were available in the published literature The literature review includes studies from the past five years (2004 to 2009). After reviewing the social marketing literature, the insight and knowledge gained was applied to develop a social marketing plan for the CATCH program. The plan was guided by Hands-on Social Marketing, A Step-by-Step Guide and the Center for Disease Control and Prevention's Social Marketing web course.^

Baseline evaluation of environmental physical activity and nutrition support of Texas Medical Center hospital worksites

Background: Obesity is a major health problem in the United States that has reached epidemic proportions. With most U.S adults spending the majority of their waking hours at work, the influence of the workplace environment on obesity is gaining in importance. Recent research implicates worksites as providing an 'obesogenic' environment as they encourage overeating and reduce the opportunity for physical activity. Objective: The aim of this study is to describe the nutrition and physical activity environment of Texas Medical Center (TMC) hospitals participating in the Shape Up Houston evaluation study to develop a scoring system to quantify the environmental data collected using the Environmental Assessment Tool (EAT) survey and to assess the inter-observer reliability of using the EAT survey. Methods: A survey instrument that was adapted from the Environmental Assessment Tool (EAT) developed by Dejoy DM et al in 2008 to measure the hospital environmental support for nutrition and physical activity was used for this study. The inter-observer reliability of using the EAT survey was measured and total percent agreement scores were computed. Most responses on the EAT survey are dichotomous (Yes and No) and these responses were coded with a '0' for a 'no' response and a '1' for a 'yes' response. A summative scoring system was developed to quantify these responses. Each hospital was given a score for each scale and subscale on the EAT survey in addition to a total score. All analyses were conducted using Stata 11 software. Results: High inter-observer reliability is observed using EAT. The percentage agreement scores ranged from 94.4%–100%. Only 2 of the 5 hospitals had a fitness facility onsite and scores for exercise programs and outdoor facilities available for hospital employees ranged from 0–62% and 0–37.5%, respectively. The healthy eating percentage for hospital cafeterias range from 42%–92% across the different hospitals while the healthy vending scores were 0%–40%. The total TMC 'healthy hospital' score was 49%. Conclusion: The EAT survey is a reliable instrument for measuring the physical activity and nutrition support environment of hospital worksites. The study results showed a large variability among the TMC hospitals in the existing physical activity and nutrition support environment. This study proposes cost effective policy changes that can increase environmental support to healthy eating and active living among TMC hospital employees.^

Effects of dietary restriction combined with different exercise programs or physical activity recommendations on blood lipids in overweight adults

Background and aim: Many exercise studies, although generally showing the beneficial effects of supervised aerobic, resistance or combined exercise on blood lipids, have sometimes reached equivocal conclusions. The aim of this study is to evaluate the impact of different programs that combined exercise and dietary restriction on blood lipids versus a clinical practice intervention for weight loss, in overweight adults. Methods: For this study 66 subjects participated in a supervised 22 weeks training program, composed of three sessions per week and they were randomized in three groups: strength training (S; n = 19), endurance training (E; n = 25), a combination of E and S (SE; n = 22). Eighteen subjects served as physical activity group (PA) that followed a clinical intervention consisted of physical activity recommendations. All groups followed the same dietary treatment, and blood samples were obtained for lipids measurements, at the beginning and end of the study. Results: Lipid profile improved in all groups. No significant differences for baseline and post-training values were observed between groups. In general, SE and PA decreased low-density lipoprotein cholesterol (LDL-C) values (p menor que 0.01). S decreased triglyceride levels (p menor que 0.01) and E, SE, and PA decreased total cholesterol levels (p menor que 0.05, p menor que 0.01 and p menor que 0.01, respectively). Conclusions: These results suggest that an intervention program of supervised exercise combined with diet restriction did not achieved further improvements in blood lipid profile than diet restriction and physical activity recommendations, in overweight adults. (Clinical Trials gov number: NCT01116856).

Physical activity and strength of the femoral neck during the adolescent growth spurt: A longitudinal analysis

Loading of the femoral neck (FN) is dominated by bending and compressive stresses. We hypothesize that adaptation of the FN to physical activity would be manifested in the cross-sectional area (CSA) and section modulus (Z) of bone, indices of axial and bending strength, respectively. We investigated the influence of physical activity on bone strength during adolescence using 7 years of longitudinal data from 109 boys and 121 girls from the Saskatchewan Paediatric Bone and Mineral Accrual Study (PBMAS). Physical activity data (PAC-Q physical activity inventory) and anthropometric measurements were taken every 6 months and DXA bone scans were measured annually (Hologic QDR2000, array mode). We applied hip structural analysis to derive strength and geometric indices of the femoral neck using DXA scans. To control for maturation, we determined a biological maturity age defined as years from age at peak height velocity (APHV). To account for the repeated measures within individual nature of longitudinal data, multilevel random effects regression analyses were used to analyze the data. When biological maturity age and body size (height and weight) were controlled, in both boys and girls, physical activity was a significant positive independent predictor of CSA and Z of the narrow region of the femoral neck (P < 0.05). There was no independent effect of physical activity on the subperiosteal width of the femoral neck. When leg length and leg lean mass were introduced into the random effects models to control for size and muscle mass of the leg (instead of height and weight), all significant effects of physical activity disappeared. Even among adolescents engaged in normal levels of physical activity, the statistically significant relationship between physical activity and indices of bone strength demonstrate that modifiable lifestyle factors like exercise play an important role in optimizing bone strength during the growing years. Physical activity differences were explained by the interdependence between activity and lean mass considerations. Physical activity is important for optimal development of bone strength. (c) 2005 Elsevier Inc. All rights reserved.