Objective: To evaluate free-living gait characteristics in comparison with in-laboratory walking among Japanese university students.
Methods: Gait characteristics (walking speed, step length, and cadence) were measured in a laboratory setting and a free-living situation. In both settings, the gait characteristics were assessed using motion sensors attached to both ankles. In the laboratory setting, subjects walked on a circular course for 5 minutes while maintaining their natural walking speed, which was assessed in 5-m walking tests. In a free-living situation, subjects were asked to wear the devices for 1 week. Frequencies of values higher than, the same as, and lower than the data measured in the laboratory were calculated for the free-living data. The effect of footwear type was also examined in a free-living situation.
Results: Eight healthy university students (age: 22.1 ± 0.4 years, six female subjects) completed the study. During the free-living period, the frequencies of slower walking speed, shorter step length, and slower cadence compared with the in-laboratory period were 79.4 ± 14.6%, 69.8 ± 25.3%, and 73.4 ± 15.6%, respectively. Walking speed, step length, and cadence were significantly lower when subjects wore slippers compared with other footwears.
Conclusion: Healthy Japanese university students’ walking speed, step length, and cadence during free-living were lower compared with the in-laboratory setting. This suggests that the evaluation of walking in an in-laboratory setting may not reflect free-living walking among university students.

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Objective: This study aimed to investigate the differences in expectations and satisfaction with a new exercise program for older adults between those who regularly participate in exercise classes and those who do not.
Methods: A questionnaire survey was conducted with participants in a Square-Stepping Exercise (SSE) trial session. Before the session, participants were asked whether they participated in regular exercise classes, their reasons for participating in the session, and their expectations from it. After the session, participants were asked about their resultant satisfaction and impressions.
Results: We analyzed subjects who had never participated in SSE before (n = 62). Of them, 32 people (75.6 ± 7.0 yrs) who regularly participated in other exercise classes were classified into an exercise class group, and 30 (73.8 ± 7.6 yrs) who did not participate were classified into a non-exercise class group. The exercise class group participated with an interest in the inexperienced exercise program, and the non-exercise class group participated expecting health benefits from the exercise. Before the session, the non-exercise group had significantly higher expectations related to factors such as “it’s fun.” Both groups showed higher satisfaction with the “good atmosphere” after the trial session compared to their expectations before the session.
Conclusion: Expectations and satisfaction with a new exercise program differ depending on whether individuals are already attending exercise classes. Trial sessions should consider participants’ characteristics.

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Objective: The results of the National Health and Nutrition Survey regarding exercise habits and step counts are utilized to set targets and monitor Japan’s health policy. A comprehensive understanding of the evolution of survey methodologies is thus essential for the effective formulation of policies within the realm of physical activity. This study aims to systematically categorize survey items pertaining to exercise habits, step counts, anthropometric measurements and physical fitness surveyed from 1946 to 2019.
Methods: This study encompasses surveys conducted from 1946 to 2019, comprising all years. Information pertaining to survey items related to exercise habits, step counts, and anthropometric measurements and physical fitness was gathered from the summaries and reports of each survey year. The data underwent systematic organization of the items, incorporating details on survey methods and any alterations made.
Results: Exercise habit is consistently defined as engagement in 30 minutes or more of exercise at least twice a week for a duration of one year or more. In this study, it was investigated through face-to-face surveys conducted by researchers since 1986. Since 1989, the pedometer from Yamasa Tokei Keiki Co., Ltd., worn at the waist, has been employed to measure daily step counts for November, excluding Sundays and holidays. The survey encompassed not only exercise habits and step counts but also delved into broader aspects, such as general physical activity, exercise, sports participation, frequency, duration, motivation, grip strength, and anthropometric measurements, and it was adapted to societal contexts.
Conclusion: The above definition of exercise habit and the pedometer to quantify step counts have been utilized consistently since the survey’s inception. Consequently, it was deemed feasible to utilize the National Health and Nutrition Survey to assess temporal variations in exercise habits and step counts.

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Objective: We examined the relationships of residential areas, age, and their interaction with active and sedentary travel in a region consisting of small- to medium-scale municipal areas.
Methods: We used data from adults in the third Higashi-Surugawan metropolitan area travel survey in December 2015 and February 2016. The outcomes were either active travel (≥ 30 min/day of walking and cycling and 0 min/day of car use) or sedentary travel (0 min/day of walking and cycling and ≥ 60 min/day of car use). The exposure categories were residential areas (regional core cities [reference]/neighboring cities), age group (young [reference], 20–44 years; middle-aged, 45–64 years; early-older adults, 65–74 years; late-older adults, 75–84 years), or their interaction terms. Logistic regression analysis was used to examine their associations.
Results: Active and sedentary travel constituted 11.2% and 27.0%, respectively, in the analytical sample (n=25,930). Neighborhood cities had significantly lower odds ratios of active travel in the comparisons of the same sex and age group. Middle-aged, early- and late-older men and middle-aged women had significantly lower odds ratios of active travel in the comparisons within the same residential area. Proportion of sedentary travel did not significantly differ by residential region, except for in early-older women, while within-region comparisons showed significantly lower odds ratios of sedentary travel in late-older men and early- and late-older women in both residential regions. No significant interactions were found in either case.
Conclusion: We found disparities in transport-related physical activity in each age group due to differences in residential areas within small- to medium-scale municipalities.

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Objective: Physical inactivity among children and adolescents with disabilities might increase the risk of serious health problems. The purpose of this study was to summarize an overview of international trends in the evaluation methodology of physical activity for children and adolescents with disabilities.
Methods: Literatures from 14 countries or jurisdictions that participated in “Global Matrix of Para Report Cards on Physical Activity of Children and Adolescents With Disabilities” were identified. Evidence to grade the overall physical activity levels in each country or jurisdiction was collected to summarize the evaluation methodology of physical activity for children and adolescents with disabilities.
Results: The Health Behaviour in School-aged Children (HBSC) questionnaire was used most frequently among the 11 countries or jurisdictions (5 countries, 45.5%). Many countries used questionnaires, including the HBSC questionnaire, that ask participants about “the number of days in which they achieved 60 minutes/day of moderate to vigorous physical activity” to evaluate their physical activity (8 countries or jurisdictions：72.7%). Three countries and 1 jurisdiction (36.4%) assigned their grade of overall physical activity using both questionnaire and accelerometer.
Conclusion: The present study showed that the frequency of achieving 60 minutes/day of moderate to vigorous physical activity using a question or questionnaire (e.g., HBSC) was the most frequently used to evaluate the overall physical activity in children and adolescents with disabilities among 11 countries or jurisdictions.

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Purpose: The protocol on graduated return to play (GRTP) after concussion was revised in August 2022 for Japanese rugby. This study aimed to investigate the occurrence of injures, including concussion, in male college rugby players and to compare the frequency of these incidents before and after the revision of the GRTP protocol following a concussion.
Methods: This study adopted epidemiological observational research design. We recorded the total number of injuries including concussions, the number of days until return to play after a concussion, and the recurrent concussions among 101 male collegiate rugby players of one team before (September to December 2021) and after (September to December 2022) the revision of GRTP protocol. We calculated the exposure time in rugby matches and trainings, the incidence rate per 1000 hours (injuries/1000 h), the 95% confidence interval (95% CI), and the rate ratio.
Results: During the study period, 146 injuries occurred. The incidence of all injures was significantly lower after the GRTP revision (6.2 injuries/1000 h; 95% CI, 4.7 - 7.6) than before the GRTP revision (8.9 injuries/1000 h; 95% CI, 6.9 - 10.9) (Rate Ratio = 0.67; 95% CI, 0.48 - 0.92). The incidence of concussion was also significantly lower after the GRTP revision (0.7 concussions/1000 h; 95% CI, 0.2 - 1.2) in comparison to before the revision (1.7 concussions/1000 h; 95% CI, 0.8 - 2.6) (Rate Ratio = 0.41; 95% CI, 0.18 - 0.92). The rate of recurrent concussions dropped from 18.7% before the GRTP protocol revision to 0% following the protocol’s revision.
Conclusions: We investigated the incidence of all injuries among male collegiate rugby players before and after the revision of the staged GRTP protocol following a concussion. And observed a decrease in the incidence of both injuries and concussions following the revision.

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Objective: This study aims to clarify the government’s dissemination measures for implementing the early childhood exercise program (hereafter, “exercise program”).
Methods: We evaluated the implementation process of exercise programs for childcare workers in Unnan City using the PAIREM model. Our evaluation utilized government, childcare facility, and preschool worker data from 2016 to 2021. We analyzed the fundamental movement skills of preschoolers up to 2019, considering the impact of the coronavirus disease 2019 pandemic on the data.
Results: Plan: The goal was to determine “the percentage (95.0%) of parents who perceive their child as being physically and mentally healthy.’’ The government planned “the number of workshops held,’’ including “the number of kindergartens and children who would participate in fundamental movement skills tests.’’ There was no target value for fundamental movement skills improvement in preschoolers. Implementation: The educational administration held 14 training sessions for childcare providers over six years. Reach: Study materials were distributed to all childcare providers. A total of 21 pseudo-childcare facilities and 18.5% (342/1849) of pseudo-childcare workers were included in the training sessions. Effectiveness: The percentage of pseudo-childcare workers’ exercise support behavior for preschoolers ranged from 75.5% to 90.4%. Furthermore, fundamental movement skills measurements showed that the softball throw and 25-meter run were higher in 2019 compared to 2016 for children aged 4–5 years. However, the standing long jump in 2019 was lower than in 2016 among children aged 5 years. Maintenance: Data will be collected in the future.
Conclusion: The evaluation by PAIREM clarified the government’s implementation of measures to disseminate exercise programs through workshops, among others. Further improvements and promotion of the project will be necessary in the future.

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Objective: We aimed to examine the effects of insulation retrofitting on sedentary behavior time (SBT) and light-to-vigorous physical activity (LVPA) at home in adults during winter.
Methods: Adults intending to retrofit their insulation participated in a 14-day baseline survey in winter and a follow-up survey 1–4 years after retrofitting. Participants were classified into an intervention (insulation retrofitting) or a control (non-insulation retrofitting) group. SBT and LVPA changes were calculated using an accelerometer and questionnaires. A multilevel model was fitted to estimate the effects of insulation retrofitting on these changes. As a secondary analysis, the change in dressing room temperature (Td) from baseline was added as an independent variable in the model, categorized as a decrease in Td (<-1.0°C), no change in Td (-1.0°C to +0.9°C), a small increase in Td (+1.0°C to +4.9°C), and a large increase in Td (≥+5.0°C).
Results: Of the 1751 participants, 1640 were in the intervention group. Both groups experienced an increase in Td. The intervention group experienced a slight increase in outside temperature, whereas the control group experienced a significant increase in outside temperature. Insulation retrofitting was not significantly associated with SBT and LVPA at home; however, the change in Td was significantly associated with SBT and LVPA. Compared to no change in Td, the large increase in Td was associated with a decrease in SBT and an increase in LVPA. In contrast, the decrease in Td was associated with an increase in SBT and a decrease in LVPA.
Conclusion: Insulation retrofitting was not associated with changes in SBT and LVPA in adults during winter. However, improving room temperature, including Td, could potentially decrease SBT and increase LVPA in adults. Further research is needed to confirm the effect of insulation retrofitting on SBT and LVPA.

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There have been projects to promote group exercise activities (circles) in Japan conducted by volunteers. Since 2009, we have been implementing several projects to promote such circles in Kasama City, Ibaraki, as well. The PAIREM model, a tool for evaluation of such projects, comprehensively evaluates the project using six dimensions (Plan, Adoption, Implementation, Reach, Efficacy/Effectiveness, and Maintenance). This study used the PAIREM model for evaluation of a project promoting circles in Kasama City. The purpose of this study was to investigate the merits and demerits of the project. Additionally, this study aims to provide an example of the data necessary for evaluation using this model.
The plan, adoption, implementation, reach, efficacy/effectiveness, and maintenance of the project in Kasama were evaluated and reported as follows. Plan: We could not report the plan because there was no information on that dimension. Adoption: Projects were implemented across the city with the involvement of five organizations. Implementation: Forty-eight educational opportunities were provided during the year for training and supporting volunteers. Reach: Thirty-two circles have been established from April 2009 to March 2017. Additionally, 661 elderly people participated in these circles. Efficacy/Effectiveness: Participation in a circle can maintain or improve the physical and cognitive functions of volunteers and other older people. Maintenance: The number of circles and people’s participation continually increased until 2021.
The project successfully increased the number of circles and female volunteers in Kasama City. However, the circles were possibly not well attended by men or the frail elderly. We need to develop projects that encourage the participation of all elderly people. Furthermore, to clarify the cost-effectiveness of such projects, it is necessary to estimate the human and economic costs of the project and investigate the effectiveness of the care prevention.

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Objective: The purpose of this cross-sectional study was to evaluate the sedentary behavior of community-dwelling older adults aged 85–89 years using an accelerometer, and to investigate its correlates, including TV viewing time, from a multifaceted perspective.
Methods: We asked 1,026 participants in the 2017–2018 baseline survey of “The Kawasaki Aging and Wellbeing Project” to wear an accelerometer for 7 consecutive days. Of these, we evaluated sedentary behavior of valid data from 914 people (473 women). Using multiple regression analysis by gender, we investigated the correlation of 25 factors with sedentary behavior ─24 factors in 3 domains (physical condition, socio-economic condition, and lifestyle) and age.
Results: The average (SD) total sedentary time and the proportion of sedentary time to wearing time of men and women were 9.4 (1.9) hours/67% per day and 8.6 (1.8) hours/59% per day, respectively. Moreover, men’s proportion of prolonged sedentary time (≥ 30 minutes) was higher than that of women. For men, the following factors were correlated with sedentary behavior in order of strength of association: screen time and BMI (positive); household work time, gardening score, exercise time, walking speed, grip strength, and ADL (negative). For women, the correlated factors were BMI and screen time (positive); household work time, sleep time, exercise time, ADL, and outing score (negative).
Conclusion: The sedentary behavior of community-dwelling older adults in their late 80s was correlated not only to screen time but also to physical condition factors (such as BMI, walking speed, grip strength, and ADL), and lifestyle factors (such as household work, gardening, exercise, sleep, and going out).

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Objective: We analyzed how early childhood physical activity (PA) and motor competence (MC) are related cross-sectionally and longitudinally.
Methods: The participants were 66 children who joined kindergarten from 2018 to 2020. They participated in this longitudinal survey for 3 years. PA and MC surveys were conducted. We assessed their moderate-to-vigorous PA (MVPA) using an accelerometer. MC consisted of four events (25m run, standing long jump, ball throw, and ball catch). A path analysis using structural equation modeling was applied to analyze the association.
Results: Cross-sectionally, in the 2nd year of kindergarten (2nd), MVPA, and each MC were weakly-to-moderately correlated (r=-.637~.450). The 3rd year kindergarteners (3rd) showed a correlation (r=.294) for ball throw and catch but not for others. Longitudinally, in the 1st year of kindergarten (1st), MVPA had a moderate effect (β=.405) on the 2nd MVPA and a weak effect (β=.352) on the 3rd MVPA. The 2nd standing long jump had a weak effect (β=.317) on the 3rd MVPA. Each 2nd MC had a weak-to-moderate effect on each 3rd MC (β=-.280~.527).
Conclusion: In this study, 2nd PA and each MC were related. Only ball throw and catch were related in the 3rd. Furthermore, 1st PA influenced 2nd and 3rd PA. We inferred that MC indirectly influences PA by changing the content and quality of play. A step-by-step approach is needed to elucidate this relation further.

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The emergence of the coronavirus disease of 2019 (COVID-19) pandemic has raised awareness regarding the use of information derived from online interventions and associated with communication technology strategies capable of reducing infection risk. However, empirical information addressing the implementation of such online interventions to promote physical activity is still scarce, and no consensus on this issue has been reached so far. Here, we aim to introduce study cases with a special focus on application strategies and online coaching for target populations (e.g., children and older adults). We also discuss the future perspectives in this rapidly evolving field. This work is based on elements discussed at the symposium on “Exercise and Health” held by the Japanese Association of Exercise Epidemiology on September 20, 2022. The primary contents are as follows: 1) merit and demerit of online interventions; 2) overview of studies using web-based systems for monitoring physical activity and wearable devices; 3) a case study of online coaching at a university; 4) a case study for kindergarten children; and 5) a case study for older adults. We expect this work foster future epidemiology studies associated with online coaching and physical exercise education programs.

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Objective: The purpose of this study was to clarify the characteristics of university students who would accept walking for only up to 10 minutes distance.
Methods: An anonymous web-based survey was conducted among 1,476 students at five universities in Okinawa Prefecture from November to December 2021, and 462 students responded (response rate: 31.3%). Data were collected for acceptable walking time (AWT), which is the distance (minutes) that people would accept walking to the destination, sex, university, grade, hometown, current residence, body mass index, driving license, transportation to and from school, and the exercise stage of change. Logistic regression analysis was used to calculate odds ratios for each explanatory variable against AWT less than 10 minutes (equivalent to within walking distance).
Results: Odds ratios for AWT less than 10 minutes were associated with 2.27 (95%CI: 1.41-3.65) for male, 1.88 (95%CI: 1.00-3.52) for normal weight against underweight, 2.79 (95%CI: 1.44-5.40) for those with a driving license, and 2.96 (95%CI: 1.86-4.69) for sedentary travelers.
Conclusion: The characteristics of university students who would accept walking for only up to 10 minutes distance were male, those who were of normal weight against underweight, those with a driving license, and sedentary travelers. The results suggested sedentary travel by car or motorcycle was associated with acceptable walking distance.

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The purpose of this study was to provide an overview of international trends in the promotion of physical activity (PA) among all children and adolescents, including those with disabilities, as well as the current situation in Japan. Today, efforts are being made worldwide to address the prevalence of physical inactivity among children, adolescents, and adults. The Sustainable Development Goals (SDGs), which pledge to "Leave no one behind," can serve as a conceptual base for such efforts. The World Health Organization (WHO)’s action plans and guidelines can contribute to the principles and goals of the SDGs. The Active Healthy Kids Global Alliance is working on a global scale for the promotion and surveillance of PA in all children and adolescents. Although several countries have reported data for children and adolescents with disabilities and/or chronic diseases since 2016, developing a comprehensive system to monitor the national and international situation is still necessary. In Japan, existing surveys on PA of children and adolescents have consistently focused on organized sports participation and there is little data on overall PA. Children and adolescents with disabilities are generally thought to be less likely to participate in organized sports when compared to able-bodied people of the same age, and the variety of sports they play can be limited. Since the WHO recommends the same values for PA irrespective of disability status, it is necessary to promote not only organized sports participation but also the overall PA among children and adolescents with disabilities.

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Objectives: The present study aimed to review the guidelines for sedentary behavior in different countries, summarize their contents, characteristics, and the background of their formulation, and obtain essential data to formulate guidelines for sedentary behavior in Japanese adults (including the elderly), children, and adolescents.
Methods: The guidelines for sedentary behavior were selected from four countries and one organization with a significant research track record on physical activity and sedentary behavior. They included Australia, the United States, Canada, the United Kingdom, and the World Health Organization (WHO).
Results: In adults, “minimizing prolonged sedentary behavior” and “breaking sedentary behavior as frequently as possible” were commonly included in all the sedentary behavior guidelines (with a minor wording difference). In children and adolescents, the sedentary behavior guidelines focused on “limiting leisure-time screen time to 2 hours” and “breaking prolonged sitting.”
Conclusion: When formulating guidelines for sedentary behavior in Japanese adults and children/adolescents, it is important to summarize the effects of sedentary behavior on various health outcomes in other countries and Japan. Furthermore, the need for identifying numerical thresholds and benchmarks in formulating sedentary behavior guidelines in Japanese adults should be further discussed.

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Objective: This report aims to examine health education in schools using a bone stiffness survey in Koshu City, Yamanashi Prefecture, based on the plan, adaptation, implementation, reach, effectiveness, and maintenance (PAIREM) framework.
Methods: The six factors of the PAIREM framework were used to evaluate the 2011-2020 health education practices of elementary and junior high schools in the city.
Results: Plan: The bone stiffness survey was an additional survey and targeted schools of interest. No specific achievement goals were set. Adoption: Although junior high schools no longer participate, adoption by primary schools has increased from 61.5% to 84.6% over the 10 years. Implementation: Health education was developed using the bone stiffness survey’s results and information was provided at the health committee (5 schools, 7 times/10 years) and bone research committee meetings (5 times/10 years). Reach: Bone stiffness measurements were obtained from 7,200 (97.8%) of the 7,362 eligible participants, indicating high achievement. All of the targeted children were provided with information on bone strength (100%). Effectiveness: As achievement goals were not set, the effectiveness of bone stiffness survey practice could not be evaluated. Maintenance: The average number of years of maintenance among the participating schools over 10 years was 8.36 years (standard deviation of 2.2), but the program’s long-term effect on individuals could not be examined.
Conclusion: The results showed that a school-based bone stiffness survey could be conducted with a high degree of achievement among children. Future practices need to understand the details of health education, perform evaluations at the individual level, and implement efforts to achieve specific targets.

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Objective: This study aimed to determine trends in adverse events during voluntary physical activity and sports performed by Sakae Ward residents.
Methods: This mixed study quantitatively and qualitatively analyzed the data obtained from a questionnaire (selective and free text) regarding accidents and injuries during sports activities conducted by Sakae Ward in 2017 for people who voluntarily engaged in sports activities. Of the 518 responses, 473 were included in the analysis.
Results: There were 94 cases (20%) with adverse events in the last 5 years. Soccer, badminton, and volleyball, in that order, had the most frequently reported adverse events. Sprain/ligament injuries of the lower extremities (26 cases), muscle/tendon injuries of the lower extremities (20 cases), and contusions of the head/face (7 cases) were the most common injuries. The results of free descriptions also confirmed the occurrence of serious injuries such as Achilles tendon rupture, anterior cruciate ligament injury of the knee joint, skull fracture, femur fracture, and cerebral hemorrhage. Muscle and tendon injuries (16 cases) were distinctive among residents in the 50–60 age group, while falls (11 cases) was distinctive in the 60–70 age group.
Conclusion: The study results show that lower limb injuries such as sprained ankle joints and adverse events such as falls among the elderly occurred during physical activity and sports voluntarily performed by Sakae Ward residents. Therefore, preventive measures and countermeasures should be taken to prevent these adverse events.

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