日足P&Fの状況：（10月14日）～（10月18日）

There is a dearth of evidence about how high-density living may influence dog-walking behaviour. We examined associations between neighbourhood built environment attributes and dog-ownership and dog-walking behaviour in Japan. Data from 1058 participants were used. The dog-ownership was 18.8%. All neighbourhood built attributes (excluding availability of parks) were negatively associated with dog-ownership. Among dog-owners, these same attributes were positively associated with any dog-walking in a usual week and with achieving 150-min per week of physical activity through dog-walking alone. These findings provided evidence on the importance of neighbourhood built environment attributes on dog-ownership and dog-walking behaviour in dense and compact areas. The urban design and public health implication of these findings is that the built environment attributes in high-density living areas may have different impacts on dog-ownership and dog-walking: while living in a walkable neighbourhood may not be conducive to dog-ownership, it may support dog-walking in such areas. Programs targeting dog-owners in high-density areas might be needed to encourage them to walk their dogs more. If successful, these programs could contribute to higher physical activity levels among dog-owners.

Previous studies have not investigated the determinants of resting oxidative stress, including physical fitness, as it relates to redox regulation. The present study therefore was aimed at identifying lifestyle and biological factors that determine resting oxidative stress, including objectively measured physical fitness. In 873 middle-aged and elderly men and women, age and anthropometric parameters, lifestyle-related parameters, medication and supplementation status, physical fitness, biochemical parameters, and nutritional intake status, as well as three plasma oxidative stress markers: protein carbonyl (PC), F2-isoprostane (F2-IsoP), and thiobarbituric acid reactive substances (TBARS), were surveyed and measured. The determinants of PC, F2-IsoP, and TBARS in all participants were investigated using stepwise multiple regression analysis. In PC, age (β = -0.11, P = 0.002), leg extension power (β = -0.12, P = 0.008), BMI (β = 0.12, P = 0.004), and HDL-C (β = 0.08, P = 0.040) were included in the regression model (adjusted R 2 = 0.018). In the F2-IsoP, smoking status (β = 0.07, P = 0.060), BMI (β = 0.07, P = 0.054), and HbA1c (β = -0.06, P = 0.089) were included in the regression model (adjusted R 2 = 0.006). In TBARS, glucose (β = 0.18, P < 0.001), CRF (β = 0.16, P < 0.001), age (β = 0.15, P < 0.001), TG (β = 0.11, P = 0.001), antioxidant supplementation (β = 0.10, P = 0.002), and HbA1c (β = -0.13, P = 0.004) were included in the regression model (adjusted R 2 = 0.071). In conclusion, the present study showed that age, anthropometric index, lifestyle-related parameters, medication and supplementation status, objectively measured physical fitness, biochemical parameters, and nutritional intake status explain less than 10% of oxidative stress at rest.

OBJECTIVES: This study examined cross-sectional and 2-year prospective associations of perceived and objectively measured environmental attributes with screen time among middle-aged Japanese adults. DESIGN: Prospective cohort study. SETTING: Nerima and Kanuma cities of Japan. PARTICIPANTS: Data were collected from adults aged 40-69 years living in two cities of Japan in 2011 (baseline: n=1011; 55.3±8.4 years) and again in 2013 (follow-up: n=533; 52.7% of baseline sample). MEASURES: The exposure variables were five geographic information system-based and perceived attributes of neighbourhood environments (residential density, access to shops and public transport, footpaths, street connectivity), respectively. The outcome variables were baseline screen time (television viewing time and leisure-time internet use) and its change over 2 years. Multilevel generalised linear modelling was used. RESULTS: On average, participants' screen time was not statistically different over 2 years (2.3 hours/day at baseline and 2.2 hours/day at follow-up; P=0.24). There were cross-sectional associations of objective (exp(β): 1.11; 95% CI 1.01 to 1.22) and perceived (1.12; 1.02 to 1.23) good access to public transport, perceived good access to shop (1.18; 1.04 to 1.36) and perceived good street connectivity (1.11; 1.01 to 1.23) with higher time spent in screen time at baseline. No objective and perceived environmental attributes were significantly associated with change in screen time. CONCLUSIONS: Activity-supportive neighbourhood environmental attributes appear to be related to higher levels of screen time cross-sectionally. Pattern of screen time might be maintained rather than changed over time under the same neighbourhood environments. Environmental interventions that promote physical activity may need to consider the potential negative health impact of screen time in Japan.

Studies have shown the potential effects of sedentary behavior and physical activity on not only physical and mental health but also academic performance in children. Nevertheless, studies have only focused on either sedentary behavior or physical activity. Examining the joint effects of both behaviors on academic performance provides detailed insights into the patterns of these behaviors in relation to children's academic achievement. The present study investigated the joint longitudinal associations of physical activity and screen time with academic performance among Japanese children. The screen time and physical activity of 261 children aged 7-10 years were assessed, and their academic performance was evaluated one year later. Multivariate logistic regression analysis was used to examine the joint associations of screen time and physical activity with academic performance adjusted for demographic characteristics. Children with low screen time and physical activity had 2.04 (95% confidence interval: 1.11-3.78) times greater odds of having high academic performance compared to children with high screen time and low physical activity, while children with low screen time and high physical activity had 2.75 (1.17-6.43) times greater odds (boys; 4.12 (1.19-14.24)). Low screen time was related to high academic performance after one year, regardless of the physical activity level.

Background: Concern over the health risks of sedentary behavior has highlighted the need to examine factors associated with screen-based (television/computer) sedentary behavior. The present study examined the association of screen-based sedentary behavior with body weight and sociodemographic attributes among Japanese adults.Methods: A population-based cross-sectional study enrolled 1034 Japanese adults aged 40 to 69 years who lived in 2 Japanese cities. Sociodemographic variables, height, weight, and time spent on screen-based sedentary behavior were collected by self-administered questionnaire. Differences in screen time in relation to body mass index and weight gain since age 20 years were assessed by the Mann-Whitney U test. Independent associations of each variable with screen time were examined by forced-entry logistic regression analyses.Results: Mean (SD) age and median (interquartile range) duration of screen time per week were 55.6 (8.4) years and 832.0 (368.8-1263.1) minutes, respectively, for men, and 55.3 (8.4) years and 852.6 (426.0-1307.5) minutes, respectively, for women. Screen time among participants with weight gain was longer than among those with a weight gain of less than 10 kg (P = 0.08). Unmarried and unemployed participants had longer screen times. Participants aged 40 to 49 years were less likely than older age groups to spend time on screen-based sedentary behavior during leisure hours.Conclusions: The present findings imply that strategies are necessary to discourage screen-based sedentary behavior among all demographic groups, especially among adults who are elderly, unmarried, or unemployed.

Built environment is an important correlate of physical activity participation. Understanding the long-term effects of environment on health behavior is necessary for the promotion of population-based physical activity. However, most studies assessing the relationships between physical activity and environment have been conducted in the United States and Australia. The present study reviews Japanese researches on built environment and physical activity, and discusses the applicability of the built environment on promoting physical activity among Japanese adults. A review was conducted by searching the PubMed and Ichushi electronic database from inception to Sept 24, 2009. Eligible articles were identified as follows : 2 studies that developed the environment scale ; 10 studies that assessed the relationships with physical activity and built environment. There have been only a limited number of studies which were conducted with Japanese adults, thus more researches are needed to draw conclusions about the built environment associated with physical activity.

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.

Background: Sedentary behaviors (SB) are associated with health indicators; however, there are currently very few studies that have examined these associations, especially in conjunction with psychological factors, in children. The current study examined the independent relationship between objectively assessed SB, and indicators of obesity and psychological, well-being, among Japanese children. Methods: A total of 967 elementary-school children completed a cross-sectional survey. SB was measured with accelerometers for 7 consecutive days. Psychological well-being data (eg, anxiety and behavior problems) were collected via a self-report questionnaire. To determine the relationship of SB with degree of obesity and psychological well-being, linear regression analyses were conducted to relate the indicators of obesity and psychological well-being on SB, adjusted by gender, grade, percentage of moderate-to-vigorous physical activity per day, duration spent wearing the accelerometer, and degree of obesity. Results: SB was significantly related to behavioral/emotional problems (beta = .280, P = .010, R-2 = .015). There was a statistically significant relationship between SB and anxiety (beta = .206, P = .059, R-2 = .007). No significant association with degree of obesity was found. Conclusions: Excess SB relates higher levels of behavioral/emotional problems and anxiety. These results can inspire the development of interventions that promote well-being and enhance psychological health, by focusing on SB in Japanese children.

Background. Comparability of accelerometers in epidemiological studies is important for public health researchers. This study aimed to compare physical activity (light, LPA; moderate, MPA; and moderate-to-vigorous, MVPA) and sedentary behavior (SB) data collected using two Omron triaxial accelerometer generations (Active style Pro, ASP) among a sample of Japanese workers in a free-living environment. Methods. Thirty active and sedentary workers (24-62 years) wore two types of ASP accelerometers, the HJA-350IT (350IT) and the HJA-750C (750C), simultaneously for seven consecutive days to represent a typical week. The accelerometers estimated daily average step counts and time spent per day in LPA, MPA, and MVPA. If a participant had data for ≥4 days (>10 h/day) it was considered valid. The difference and agreement between the two ASPs were analyzed using a paired t-test, intra-class correlation coefficients (ICC), and a Bland-Altman analysis in total and for each type of worker. Results. Among all workers, the 750C measured significantly (p < 0.05) less SB, MPA, MVPA, and more LPA compared with the 350IT. The agreements in ICC were high (ICC ≥ 0.94). Conclusions. Compared with the 350IT, the newer generation 750C ASP accelerometer may not provide equivalent estimates of activity time, regardless of the type of physical activity.

BackgroundPhysical activity and physical performance relate to quality of life, mortality, and morbidity in elderly people. However, little is known about differences in physical performance related to low-intensity light physical activity (LLPA), high-intensity light physical activity (HLPA), and moderate-intensity physical activity (MPA) and how they are separated by sex in elderly populations.AimsThis study aimed to determine differences in LLPA, HLPA, MPA, and physical performance, and associations between these measures in community-dwelling elderly men and women.MethodsPhysical activity and physical performance such as timed-up-and-go test, one-leg standing time, and maximum gait speed were measured in 181 community-dwelling elderly men (mean age, 75.1 +/- 5.3 years) and 109 women (mean age, 73.4 +/- 4.8 years) in 2013. Physical activity was classified as LLPA (1.6 +/- 1.9 METs of physical activity), HLPA (2.0 similar to 2.9 METs of physical activity), and MPA (over 3 METs of physical activity). The association between the values of these three intensities of physical activity in the participants was assessed by Pearson's correlation coefficients. Multiple linear regression analyses were used to assess the association of physical performance values with the three groups defined by accelerometer- measured physical activity intensity adjusted for sociographic, behavioral, and multiple diseases in the participants.ResultsMPA was beneficially associated with all physical performance indicators in the men (all P 0.05) and women (all P 0.05). Only HLPA showed significant associations with the timed-up-and-go test (P = 0.001) and maximum gait speed (P = 0.006) in women. Discussion These results may support the notion that not only HLPA in women but MPA in both sexes appears to improve physical performance in elderly populations. Conclusion The present study findings provide novel epidemiological evidence for the potential benefits of HLPA in women and also reinforce the potential benefits of MPA in both sexes, which is the mainstay of public health recommendations.

Background: It is vital to reduce the proportion of sedentary behavior in children. Understanding the duration and behavioral context is needed. The present study examined school-grade and sex differences in domain-specific sedentary times and concurrence with screen-time guidelines among Japanese elementary school children.Methods: A total of 625 children (330 boys) were surveyed in 2010 and 2014. Using a questionnaire, data regarding participants' grade (first through third grades: lower grades; fourth through six grades: higher grades), sex, weight, and height were collected in addition to the time spent per day engaging in each specific sedentary behavior separately: (1) reading or listening to music, (2) TV or video viewing, (3) TV game use, (4) internet use excluding class, (5) homework, and (6) car travel. Two-way analysis of covariance and logistic regression analyses, adjusted for BMI and moderate to vigorous physical activity, were used to examine school-grade and sex differences in sedentary behaviors and the independent risk of exceeding recommended total daily screen time ( 2 h).Results: On 625 children, mean minutes (SD) of sedentary behavior per week in (1) - (6) were 90.3 (123.4), 535.0 (356.6), 167.3 (222.1), 23.9 (70.9), 264.9 (185.3), and 33.4 (61.2) in weekdays and 42.1 (70.0), 323.9 (232.0), 123.0 (96.4), 15.8 (49.9), 74.4 (96.4), and 71.3 (84.9) in weekends, respectively. There were differences in the minutes of sedentary behavior between participants of 2010 and 2014; e.g., TV game use and homework in weekdays and weekdays and car travel in weekends. Boys spent more time in TV game use, and girls spent more time reading, listening to music, doing homework, and car travel. Higher-grade students spent more time reading or listening to music, using a computer, and doing homework. Higher-grade students were 2.09 times (95% CI: 1.32 - 3.30) in whole week, 2.08 times (95% CI: 1.45 - 3.00) in weekday, and 1.88 times (95% CI: 1.29 - 2.74) in weekend more likely to spend = 2 h per day in domains (2) - (4) (screen-time) than lower-grade students.Conclusions: Time spent engaging in each domain-specific sedentary behavior differed according to sex and school grade. Higher-grade students were less likely to meet screen-time guidelines. These findings highlight the need for domain-focused strategies to decrease sedentary behavior in Japanese school-age children.

Although greater sedentary time has been found to be associated with negative health impacts, little is known whether the specific pattern of sedentary behavior (i.e. sedentary bouts, breaks and durations) are associated with physical function among older adults. The present study examined the associations between objectively measured sedentary behavior and physical function among older Japanese adults. A total of 174 male and 107 female community-dwelling older Japanese adults aged 65-84 years (mean age: 74.5 ± 5.2 years) were recruited. Sedentary behavior and physical activity were assessed using a triaxial accelerometer. Physical function was measured through hand grip strength, eye-open one leg standing, 5-m walking, and timed up and go tests. Forced-entry multiple linear regression models adjusted for potential confounders were performed. After adjustment, total daily sedentary time and duration of prolonged sedentary bouts (both ≥ 30 min) were positively associated with time spent on the 5-m walking stage and timed up and go tests in older women; however, no significant associations were observed in older men or the whole sample. This paper highlights the importance of developing sedentary behavior change strategies for interventions aiming to improve mobility in in older women. Further evidence from a prospective study is required to establish directions of causality between sedentary behavior and mobility.

本研究の目的は、高齢者における座位行動の現状と健康影響を明らかにすることであった。ベースライン調査・測定の結果、一日の覚醒時間のうち座位行動が占める割合は58％（8.7時間）で、1回30分以上継続する長時間の座位行動は4.4回（総座位行動時間の42％）であった。男性、後期高齢者、過体重・肥満者における総座位時間等が最も長かった。テレビの視聴における座位行動が最も座りすぎを助長する生活場面（46.9％）であった。また、10分間の座位行動から中等度以上の身体活動への置換は、健康関連QOLや多くの身体機能（歩行能力等）の改善に有用である可能性が明らかとなった。今後は、縦断的検討を行っていく。

Background–Several non-pharmaceutical policies, which include stay-at-home orders, mobility restrictions, and quarantine, have been implemented to reduce the spread of novel coron-avirus disease 2019 (COVID-19). The present study examines work style changes among company workers after COVID-19 and analyses their effects on workers’ domain-specific sedentary and active behaviours. Methods-We analysed data from a nationwide prospective online survey in Japan. The data were obtained in February 2019 (n = 3200) and in July 2020 (n = 1709) from the registered individuals of a Japanese internet research service company. The participants reported work style patterns before and after the outbreak of COVID-19 in the follow-up survey. Domain-specific sedentary behaviours and physical activities were assessed by questionnaires. Paired t-tests were used to compare work styles before and after the outbreak of COVID-19. Multivariable linear regression models were used to assess the associations between changes in work style and changes in sedentary behaviours and physical activities. Results. Workers had more working from home days and fewer office-based working days after the outbreak of COVID-19 (p < 0.001 and p < 0.001, respectively). The increase in the number of working from home days per week was significantly associated with increases in work-related sitting time and total sitting time (b = 0.16, 95% CI 0.08, 0.24, p < 0.001 and b = 0.23, 95% CI 0.11, 0.36, p < 0.001, respectively). However, it was also associated with a decrease in car sitting time (b = −0.04, 95% CI −0.06,-0.01, p < 0.001). In addition, the increase in the number of working from home days was associated with a decrease in work-related moderate physical activity (b =−0.06, 95% CI −0.10, −0.02, p < 0.001). Conclusions. Our study provided preliminary evidence of an increase in working from home days in response to COVID-19 in Japan and of how this increase in the number of working from home days has affected workers’ sedentary behaviours and physical activities. These findings shed light on the effects of COVID-19 on work styles and workers’ sedentary behaviours and physical activity.

Background: In the rapidly developing use of the Internet in society, eHealth literacy-having the skills to utilize health information on the Internet-has become an important prerequisite for promoting healthy behavior. However, little is known about whether eHealth literacy is associated with health behavior in a representative sample of adult Internet users.Objective: The aim of this study was to examine the association between eHealth literacy and general health behavior (cigarette smoking, physical exercise, alcohol consumption, sleeping hours, eating breakfast, eating between meals, and balanced nutrition) among adult Internet users in Japan.Methods: The participants were recruited among registrants of a Japanese Internet research service company and asked to answer a cross-sectional Internet-based survey in 2012. The potential respondents (N= 10,178) were randomly and blindly invited via email from the registrants in accordance with the set sample size and other attributes. eHealth literacy was assessed using the Japanese version of the eHealth Literacy Scale. The self-reported health behaviors investigated included never smoking cigarettes, physical exercise, alcohol consumption, sleeping hours, eating breakfast, not eating between meals, and balanced nutrition. We obtained details of sociodemographic attributes (sex, age, marital status, educational attainment, and household income level) and frequency of conducting Internet searches. To determine the association of each health behavior with eHealth literacy, we performed a logistic regression analysis; we adjusted for sociodemographic attributes and frequency of Internet searching as well as for other health behaviors that were statistically significant with respect to eHealth literacy in univariate analyses.Results: We analyzed the data of 2115 adults (response rate: 24.04%, 2142/10,178; male: 49.74%, 1052/2115; age: mean 39.7, SD 10.9 years) who responded to the survey. Logistic regression analysis showed that individuals with high eHealth literacy were significantly more likely to exhibit the good health behaviors of physical exercise (adjusted odds ratio [AOR] 1.377, 95% CI 1.131-1.678) and eating a balanced diet (AOR 1.572, 95% CI 1.274-1.940) than individuals with low eHealth literacy.Conclusions: We found that some health behaviors, including exercise and balanced nutrition, were independently associated with eHealth literacy among Japanese adult Internet users.