Journal of Medical Internet Research - International Scientific Journal for Medical Research, Information and Communication on the Internet

Objective measures of environmental attributes have been used to understand how neighborhood environments relate to physical activity. However, this method relies on detailed spatial data, which are often not easily available. Walk Score® is a free, publicly available web-based tool that shows how walkable a given location is based on objectively-derived proximity to several types of local destinations and street connectivity. To date, several studies have tested the concurrent validity of Walk Score as a measure of neighborhood walkability in the USA and Canada. However, it is unknown whether Walk Score is a valid measure in other regions. The current study examined how Walk Score is correlated with objectively-derived attributes of neighborhood walkability, for residential addresses in Japan. Walk Scores were obtained for 1072 residential addresses in urban and rural areas in Japan. Five environmental attributes (residential density, intersection density, number of local destinations, sidewalk availability, and access to public transportation) were calculated using geographic information systems for each address. Pearson's correlation coefficients between Walk Score and these environmental attributes were calculated (conducted in May 2017). Significant positive correlations were observed between Walk Score and environmental attributes relevant to walking. Walk Score was most closely associated with intersection density (r = 0.82) and with the number of local destinations (r = 0.77). Walk Score appears to be a valid measure of neighborhood walkability in Japan. Walk Score will allow urban designers and public health practitioners to identify walkability of local areas without relying on detailed geographic data.

Background: Sedentary behaviors and physical activity are likely to be affected by the COVID-19 outbreak, and sedentary lifestyles can increase subjective fatigue. The nonpharmaceutical policies imposed as a result of the COVID-19 pandemic may also have adverse effects on fatigue. Objective: This study has two aims: to examine the changes in sedentary behaviors and physical activity of company workers in response to the COVID-19 pandemic in Japan and to examine relationships between changes in these sedentary behaviors and physical activity and changes in fatigue. Methods: Data from a nationwide prospective online survey conducted in 2019 and 2020 were used. On February 22, 2019, an email with a link to participate in the study was sent to 45,659 workers, aged 20 to 59 years, who were randomly selected from a database of approximately 1 million individuals. A total of 2466 and 1318 participants, who self-reported their occupation as company workers, answered the baseline and follow-up surveys, respectively. Surveys captured fatigue, workday and daily domain-specific sedentary behaviors and physical activity, and total sedentary behaviors and physical activity. We used multivariable linear regression models to estimate associations of changes in sedentary behaviors and physical activity with changes in fatigue. Results: Increases in public transportation sitting during workdays, other leisure sitting time during workdays, and other leisure sitting time were associated with an increase in the motivation aspect of fatigue (b=0.29, 95% CI 0-0.57, P=.048; b=0.40, 95% CI 0.18-0.62, P<.001; and b=0.26, 95% CI 0.07-0.45, P=.007, respectively). Increases in work-related sitting time during workdays, total sitting time during workdays, and total work-related sitting time were significantly associated with an increase in the physical activity aspect of fatigue (b=0.06, 95% CI 0-0.12, P=.03; b=0.05, 95% CI 0.01-0.09, P=.02; and b=0.07, 95% CI 0-0.14, P=.04, respectively). The motivation and physical activity aspects of fatigue increased by 0.06 for each 1-hour increase in total sitting time between baseline and follow-up (b=0.06, 95% CI 0-0.11, P=.045; and b=0.06, 95% CI 0.01-0.10, P=.009, respectively). Conclusions: Our findings demonstrated that sedentary and active behaviors among company workers in Japan were negatively affected during the COVID-19 outbreak. Increases in several domain-specific sedentary behaviors also contributed to unfavorable changes in workers’ fatigue. Social distancing and teleworking amid a pandemic may contribute to the sedentary lifestyle of company workers. Public health interventions are needed to mitigate the negative effects of the COVID-19 pandemic or future pandemics on sedentary and physical activity behaviors and fatigue among company workers.

In the context of rapid urbanization, public open spaces in dense urban areas are critical built environment elements to support active lifestyles. Several reviews have explored the associations of public open space attributes with physically active and sedentary behavior. However, few reviews have included studies from Asia, and no studies have focused on dense urban areas. This systematic review analyzed 18 observational studies investigating associations between public open space attributes with physical activity and sedentary behavior in dense urban areas of East Asian countries, including Japan, Taiwan, China, and Hong Kong. We found that closer distance to and a greater number of public open spaces and features within them were positively associated with leisure-time physical activity. Places near water features and corridors within public open spaces were associated with more sedentary behavior. These findings inform landscape and urban design guidelines for (re)designing public open spaces to support active lifestyles in high dense urban areas.

Preventing social isolation is essential for promoting healthy aging. This study aims to 1) systematically review and synthesize the predictors of objectively measured social isolation from observational studies that have treated isolation as an outcome in community-dwelling older adults, and 2) overview previous studies in this area and reveal an agenda to develop future research. Peer-reviewed primary studies published in English or Japanese were identified from PubMed, ScienceDirect, PsycINFO, Igaku-Chuo-Zasshi, and CiNii. We followed the PRISMA statement. Risk of bias of included studies was assessed using the Newcastle-Ottawa Scale. Of the 1,161 studies identified, 10 were included in the review. Most studies were cross-sectional and published in the past 20 years. The risk of bias score ranged from 3 to 6 for the individual studies, indicating a moderate to high risk. The assessment measures for social isolation and proportion of isolated subjects varied greatly across studies. Findings on the predictors of social isolation from each study were clustered into four categories: socio-demographic factors, physical health factors, psychological and cognitive factors, and social and cultural factors. It was difficult to confirm these predictors conclusively because of the cross-sectional study design and a huge variety of assessment tools for social isolation. This result suggests the need to build consensus on the appropriate scales and standard cut-off points for assessing social isolation. Furthermore, longitudinal studies are urgently required. When considering predictors of social isolation, it is also essential to consider the regional and ethnic background of the samples studied.