Tomoko Takamiya

Association between perceived neighborhood environment and walking among adults in 4 cities in Japan

Background Recent research highlights the importance of environment as a determinant of physical activity; however, evidence among Japanese is sparse. The aim of this study was to examine the association between perceived neighborhood environment and neighborhood walking for multiple purposes among Japanese. Methods We conducted a population-based, cross-sectional study of 1461 Japanese adults (age: 48.2 ± 14.1 years, men: 44.8%). Neighborhood environment and walking were assessed by a validated questionnaire. The odds ratio of active walkers was calculated in relation to environmental characteristics after adjustment for age, sex, and other potential confounders. Results Participants were more likely to walk when they perceived that there was high residential density (odds ratio, 1.47; 95% confidence interval, 1.11–1.96), fair land use mix–diversity (1.37, 1.04–1.81), good walking/cycling facilities (1.56, 1.19–2.04), and attractive aesthetics (1.49, 1.14–1.95). Environmental factors associated with walking differed with respect to the purpose for walking. The environmental characteristics associated with walking for daily errands and with walking for commuting were similar, and included residential density and land use mix. Walking for leisure was associated with walking/cycling facilities, aesthetics, and traffic safety. Stratified analyses showed some sex-specific associations. Among women, there was an unexpected inverse association of leisure walking with both residential density and land use mix–diversity. Conclusions The association between neighborhood environment and walking differed by walking purpose. The results were generally consistent with those of studies conducted in Western countries, except for the association of high residential density and good land use mix–diversity with less leisure walking in women. These results suggest possible targets for environmental interventions to promote walking.

Association of physical activity and neighborhood environment among Japanese adults.

OBJECTIVE Although environmental attributes related to physical activity is an emerging research topic, most studies have been reported from Western countries. This study aimed to examine the relationship between perceived environment and physical activity among Japanese adults. METHODS The sample included 492 adults aged 20 to 74 years (61%: male) living in Tokyo and Himeji in Japan. Primary measures were the short version of International Physical Activity Questionnaire and its Environmental Module. Data were collected between October and December 2003. Odds ratio (OR) of meeting physical activity recommendations was examined in relation to neighborhood environmental characteristics, adjusted for age, sex, employment status and education. RESULTS Three perceived environmental attributes were significantly related to walking 150 min/week or more: high residential density (OR=1.82), good access to shops (OR=1.65) and presence of sidewalks (OR=1.65). Two environmental attributes, access to shops (OR=2.32) and the presence of bike lanes (OR=1.57), were related to high levels of moderate to vigorous physical activity (950 MET*min/week or more). CONCLUSION Associations of physical activity with four environmental attributes emerged in this Japanese sample. These results support the generalizability of findings on physical activity environments across Western countries and Japan.

Television viewing time is associated with overweight/obesity among older adults, independent of meeting physical activity and health guidelines

Background Previous studies have shown associations of sedentary behavior with cardiovascular risk, independent of moderate-to-vigorous physical activity (MVPA). However, few studies have focused on older adults. This study examined the joint associations of television (TV) viewing time and MVPA with overweight/obesity among Japanese older adults. Methods A population-based, cross-sectional mail survey was used to collect self-reported height, weight, time spent in TV viewing, and MVPA from 1806 older adults (age: 65–74 years, men: 51.1%). Participants were classified into 4 categories according to TV viewing time (dichotomized into high and low around the median) and MVPA level (dichotomized into sufficient and insufficient by the physical activity guideline level of ≥150 minutes/week). Odds ratios (ORs) for overweight/obesity (body mass index ≥25 kg/m2) were calculated according to the 4 TV/MVPA categories, adjusting for potential confounders. Results Of all participants, 20.1% were overweight/obese. The median TV viewing time (25th, 75th percentile) was 840 (420, 1400) minutes/week. As compared with the reference category (high TV/insufficient MVPA), the adjusted ORs (95% CI) of overweight/obesity were 0.93 (0.65, 1.34) for high TV/sufficient MVPA, 0.58 (0.37, 0.90) for low TV/insufficient MVPA, and 0.67 (0.47, 0.97) for low TV/sufficient MVPA. Conclusions In this sample of older adults, spending less time watching TV, a predominant sedentary behavior, was associated with lower risk of being overweight or obese, independent of meeting physical activity guidelines. Further studies using prospective and/or intervention designs are warranted to confirm the presently observed effects of sedentary behavior, independent of physical activity, on the health of older adults.

Perceived neighborhood environment and walking for specific purposes among elderly Japanese.

Background Recent research has revealed the importance of neighborhood environment as a determinant of physical activity. However, evidence among elderly adults is limited. This study examined the association between perceived neighborhood environment and walking for specific purposes among Japanese elderly adults. Methods This population-based, cross-sectional study enrolled 1921 participants (age: 65–74 years, men: 51.9%). Neighborhood environment (International Physical Activity Questionnaire Environmental Module) and walking for specific purposes (ie, transportation or recreation) were assessed by self-report. Multilevel logistic regression analyses with individuals at level 1 and neighborhoods at level 2 were conducted to examine the association between environment and walking, after adjustment for potential confounders. Results Access to exercise facilities, social environment, and aesthetics were associated with total neighborhood walking. Odds ratios (95% CI) were 1.23 (1.00–1.51), 1.39 (1.14–1.71), and 1.48 (1.21–1.81), respectively. Regarding walking for specific purposes, social environment and aesthetics were consistent correlates of both transportation walking and recreational walking. Environmental correlates differed by specific types of walking and by sex. Transportation walking significantly correlated with a greater variety of environmental attributes. Sex differences were observed, especially for transportation walking. Bicycle lanes, crime safety, traffic safety, aesthetics, and household motor vehicles were significant correlates among men, while access to shops, access to exercise facilities, and social environment were important among women. Conclusions Specific environment–walking associations differed by walking purpose and sex among elderly adults. Social environment and aesthetics were consistent correlates of both transportation walking and recreational walking. Improving these environmental features might be effective in promoting physical activity among elderly Japanese.

Resistance Exercise Enhances Cognitive Function in Mouse

Physical exercise has been shown to increase adult neurogenesis in the hippocampus and to enhance synaptic plasticity. It has been demonstrated that these neuroprotective effects can be observed following aerobic exercise. However, it remains unknown whether plasticity molecules, such as brain-derived neurotrophic factor (BDNF) and cyclic AMP response element-binding protein (CREB), are expressed in the hippocampus following resistance exercise. We applied voluntary progressive-resistance wheel exercise (RE) for 14 days, and measured BDNF and CREB in the hippocampus. The Morris water maze was also performed to estimate learning and memory. Furthermore, we measured RE effects on mammalian target of rapamycin (mTOR) and 70-kDa ribosomal protein S6 kinase (p70S6K) mediating muscle protein synthesis in the soleus. As a result, we found that RE enhanced cognition and elevated BDNF and CREB expressions in the hippocampus. Also, RE activated the mTOR-p70S6K signaling pathway in the soleus. We found that phosphorylated mTOR and p70S6K were significantly positively correlated with BDNF expression. Our results indicated that resistance exercise drove the protein synthesis signaling pathway in the soleus and enhanced hippocampal synaptic plasticity-related molecules. These results suggest the beneficial effects of resistance exercise on cognitive function.

Effect on Mental Health of a Participatory Intervention to Improve Psychosocial Work Environment: A Cluster Randomized Controlled Trial among Nurses

Effect on Mental Health of a Participatory Intervention to Improve Psychosocial Work Environment: A Cluster Randomized Controlled Trial among Nurses: Ayako UCHIYAMA, et al. Department of Preventive Medicine and Public Health, Tokyo Medical University, Japan—

Sociodemographic variation in the perception of barriers to exercise among japanese adults

Background The perception of barriers to exercise is an important correlate of exercise participation. However, only a limited number of studies—mostly from Western countries—have attempted to describe the perceptions of barriers to exercise in specific population groups. This study examined the associations between sociodemographic attributes and perceived barriers to exercise in Japanese adults. Methods A population-based cross sectional study of 865 participants (age: 20–69 years old, men: 46.5%) was conducted in 4 cities in Japan. Nine sociodemographic attributes (sex, age, location of residence, educational attainment, marital status, employment status, presence of dependents in the household, self-rated health, body mass index), along with exercise frequency and perception of barriers to exercise (discomfort, lack of motivation, lack of time, lack of social support, poor environment) were assessed by self-administered questionnaire. Results The most strongly perceived barrier was lack of time. Five of 9 sociodemographic attributes were significantly related to certain types of perceived barriers. Participants who more strongly perceived barriers were younger, more highly educated, more likely to be employed, and had relatively poor self-rated health and a high BMI. The specific types of barriers that were strongly perceived varied with the sociodemographic attributes of the participants. Conclusions The results show that the perception of barriers to exercise varies among specific population groups, which indicates the importance of targeting exercise promotion strategies to specific populations.

Sociodemographic determinants of pedometer-determined physical activity among Japanese adults.

BACKGROUND Although previous studies have reported physical activity and its sociodemographic determinants using self-report measures, there have been few studies using pedometers. PURPOSE To ascertain pedometer-determined physical activity and its sociodemographic determinants among community residents living in four Japanese cities. METHODS A cross-sectional mail survey was conducted from February 2007 to January 2008 with a sample of 4000 residents (aged 20-69 years and 50% male) who were randomly selected from the registry of residential addresses. Complete responses for both questionnaire and pedometer were obtained from 790 residents (48.3±13.7 years, 46.7% male). Associations of 11 sociodemographic variables with steps per day were examined using multiple logistic regression analyses. Data were analyzed in 2010. RESULTS Men averaged 8763±3497 steps/day and women averaged 8242±3277 steps/day. Further, 29.0% of men and 27.8% of women walked ≥10,000 steps/day. City of residence, good self-rated health, low educational attainment, and not owning a car were associated with taking ≥10,000 steps/day in men, whereas employed status and dog ownership were associated with walking ≥10,000 steps/day in women. CONCLUSIONS The results contribute to understanding of step-defined physical activity and its sociodemographic determinants. A diversity of step counts by sociodemographic variables clarifies specific populations among Japanese who are in need of intervention to promote physical activity.

Characteristics of Accelerometry Respondents to a Mail-Based Surveillance Study

Background Differences in the characteristics of respondents and nonrespondents to a survey can be a cause of selection bias. The aim of this study was to determine the sociodemographic and lifestyle characteristics of respondents to a field-based accelerometry survey. Methods A cross-sectional mail survey was sent to 4000 adults (50% male; age 20 to 69 years) who were randomly selected from the registries of residential addresses of 4 cities in Japan. There were 1508 respondents (responding subsample) to the initial questionnaire. A total of 786 participants from the responding subsample also agreed to wear an accelerometer for 7 days (accelerometer subsample). Age, sex, and city of residence were compared between the accelerometer subsample and all 3214 nonrespondents, including those who did not respond to the initial questionnaire. In addition, multiple logistic regression analyses were used to compare the sociodemographic and lifestyle characteristics of the accelerometer subsample and the 722 respondents who participated in the questionnaire survey but not the accelerometry (questionnaire-only subsample). Results As compared with all nonrespondents, the accelerometer subsample included significantly more women, middle-aged and older adults, and residents of specific cities. Multiple logistic regression analyses comparing the accelerometer and questionnaire-only subsamples revealed that participation in the accelerometry survey was greater among nonsmokers (odds ratio, 1.35; 95% confidence interval, 1.02–1.79) and persons who reported a habit of leisure walking (1.56, 1.21–2.01). Conclusions Sex, age, city of residence, smoking status, and leisure walking were associated with participation in accelerometry. This response pattern reveals potential selection bias in mail-based accelerometry studies.

Organizational justice and insomnia: Relationships between justice components and insomnia symptoms among private company workers in Japan

Organizational justice and insomnia: Relationships between justice components and insomnia symptoms among private company workers in Japan: Toshio Hayashi, et al. Department of Preventive Medicine and Public Health, Tokyo Medical University