Trends in Step-determined Physical Activity among Japanese Adults from 1995 to 2016

Association of the interaction between daily step counts and frailty with disability in older adults

The differences in the association of objectively measured physical activity with disability between frail and non-frail older adults remain unclear. We (1) evaluated the dose-dependent relationship between daily steps and disability in older adults with and without frailty and (2) examined the interaction between steps and frailty status in relation to the risk of disability. This prospective study used data from 4065 adults aged ≥ 65 years from the Kyoto-Kameoka Study, Japan. The mean daily step count obtained using triaxial accelerometers across ≥ 4 days was recorded. Frailty was evaluated using the validated Kihon Checklist. Disability was identified using the long-term care insurance system's nationally unified database, with data collected until November 30, 2016. Overall, 385 disabilities were recorded during a median follow-up period of 3.32 years (12,855 person-years). After adjusting for confounders, an inverse association was observed between daily step count and disability risk. The disability risk plateaued at 5,000-7,000 steps/day in non-frail people, whereas step counts showed an almost linear inverse relationship with disability risk in frail people. Low step counts (< 5,000 steps) in frail people were more strongly associated with disability risk than were high step counts (≥ 5,000 steps) in non-frail people. The additive interaction between steps and frailty was associated with the relative excess risk of disability in frail people with low step counts (p for interaction = 0.015). The relationship between daily steps and disability differs between older adults with and without frailty, and the adverse effects of frailty on disability risk depend on physical activity.

Two-year scale-up dissemination study of a multi-strategic community-wide intervention promoting physical activity: a single-arm pre-post hybrid effectiveness-implementation trial

BACKGROUND

Intervention trials that have demonstrated significant effects may not always replicate those effects when scaled up. This study aimed to test whether scaling-up a successful cluster randomized trial (the COMMUNICATE study, 9 intervention communities), which promoted population-level physical activity (PA), could promote PA in a broader citywide setting (29 communities) after two years, as a mid-term evaluation of the six-year scaled-up trial.

METHODS

This is a single-arm, pre-post comparison of a multi-strategic community-wide intervention covering the entire Unnan City, Japan. The intervention for middle-aged and older people consisted of three components: information delivery, education, and support delivery. The intervention method followed the COMMUNICATE study but adapted and introduced new initiatives tailored to local resources. A baseline survey (n = 3,718) among randomly selected residents aged 40-79 years in 2016 and a follow-up survey with the same respondents two years later were conducted. The primary outcome was the change in the percentage of people who practiced the recommended levels of PA, analyzed with a generalized linear mixed model to account for clusters at individual and community levels. Additionally, we examined the dose-response relation of the effect based on the intervention doses in each community. The RE-AIM framework assessed intervention dissemination and implementation.

RESULTS

The two-year intervention was implemented in all communities, reaching and involving various groups. The rate of people engaged in PA significantly increased in two years (adjusted change: + 8.0 percentage points [95% confidence interval: 6.1, 10.0]). Based on the type of PA, only muscle-strengthening activity showed a significant increase (+ 11.5% points [9.6, 13.5]), whereas walking (-1.8% points [-3.6, 0.1]) and flexibility activities (+ 0.3% points [-1.5, 2.0]) did not. The increase in PA in higher-dose areas was not significantly different but slightly larger than that in lower-dose areas (+ 8.4% points vs. + 7.6% points, adjusted difference in change: 0.8% points [-3.8, 5.5]).

CONCLUSION

The scaled-up citywide intervention promoted PA, especially muscle-strengthening activity. Collaboration with diverse organizations in different settings is crucial for multi-faceted interventions and requires balancing uncertainty in its implementation quality and quantity owing to collaborative decision-making.

TRIAL REGISTRATION

UMIN-CTR, UMIN000024682. Registered 02 November 2016, https://center6.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000028377.

Device-measured physical activity and sedentary time in the Nordic countries: A scoping review of population-based studies

PURPOSE

The purpose of this scoping review was to summarize and describe the methodology and results from population-based studies of physical activity and sedentary time measured with devices in the Nordic countries (Denmark, Finland, Iceland, Norway, and Sweden) and published in 2000 or later.

METHODS

A systematic search was carried out in PubMed and Web of Science in June 2023 using predefined search terms.

RESULTS

Fourteen unique research projects or surveillance studies were identified. Additionally, 2 surveillance studies published by national agencies were included, resulting in a total of 16 studies for inclusion. National surveillance systems exist in Finland and Norway, with regular survey waves in school-aged children/adolescents and adults. In Denmark, recent nationally representative data have been collected in school children only. So far, Sweden has no regular national surveillance system using device-based data collection. No studies were found from Iceland. The first study was conducted in 2001 and the most recent in 2022, with most data collected from 2016 to date. Five studies included children/adolescents 6-18 years, no study included preschoolers. In total 11 studies included adults, of which 8 also covered older adults. No study focused specifically on older adults. The analytical sample size ranged from 205 to 27,890. Detailed methodology is presented, such as information on sampling strategy, device type and placement, wear protocols, and physical activity classification schemes. Levels of physical activity and sedentary time in children/adolescents, adults, and older adults across the Nordic countries are presented.

CONCLUSION

A growing implementation of device-based population surveillance of physical activity and sedentary behavior in the Nordic countries has been identified. The variety of devices, placement, and data procedures both within and between the Nordic countries highlights the challenges when it comes to comparing study outcomes as well as the need for more standardized data collection.

Comparison of step-count outcomes across seven different activity trackers: a free-living experiment with young and older adults

BACKGROUND

There are now many different types of activity trackers, including pedometers and accelerometers, to estimate step counts per day. Previous research has extensively examined step-count measurements using activity trackers across various settings while simultaneously wearing different devices.; however, older adults frequently display distinct walking patterns and gait speeds compared to younger adults. This study aimed to compare the step-count between older and younger adults by having them simultaneously wear seven different activity trackers in free-living experiments.

METHODS

This study included 35 younger adults (21-43 yrs) and 57 physically independent older adults (65-91 yrs). All participants simultaneously wore one pedometer and six activity trackers: ActiGraph GT3X + Wrist and Hip, Omron Active Style Pro HJA-350IT, Panasonic Actimarker, TANITA EZ-064, Yamasa TH-300, and Yamasa AS-200 for seven days. A regression equation was also used to assess inter-device compatibility.

RESULTS

When comparing wrist-worn ActiGraph to the six hip-worn activity trackers, the wrist-worn ActiGraph consistently recorded step counts over 4,000 steps higher than hip-worn activity trackers in both groups (range, 3000-5000 steps). Moreover, when comparing the ActiGraph worn on the wrist to that worn on the hip, the proportion was higher among older adults compared to younger ones (younger: 131%, older: 180%). The Actimarker recorded the highest average step counts among six hip-worn devices, with 8,569 ± 4,881 overall, 9,624 ± 5,177 for younger adults, and 7,890 ± 4,562 for older adults. The difference between the hip-worn ActiGraph and Active Style Pro was just about 70 steps/day overall. The correlation among all devices demonstrated a very high consistency, except for the wrist-worn ActiGraph (r = 0.874-0.978).

CONCLUSIONS

Step counts recorded from seven selected consumer-based and research-grade activity trackers and one pedometer, except for the wrist-worn ActiGraph. showed a variation of approximately 1700 steps (range, 1265-2275 steps) steps for both groups, yet maintained a high correlation with each other. These findings will be valuable for researchers and clinicians as they compare step counts across different studies or representative surveys conducted globally.

Data resource profile: Exercise habits, step counts, and sedentary behavior from the National Health and Nutrition Survey in Japan

The National Health and Nutrition Survey consistently assesses the prevalence of exercise habits, step counts, and sedentary behaviors in a strategically selected random sample of the Japanese population. The aim of this study was to provide descriptive epidemiological data on the average frequency of exercise habits, daily step counts, and sedentary behavior among Japanese adults from 2003 to 2019 using the National Health and Nutrition Survey database in Japan. Data were obtained from electronically available aggregate reports on the official survey website. To prepare for the third term of Health Japan 21, scheduled to start in 2024, we summarized population-level trends in exercise habits, step counts, and sedentary behavior among Japanese adults. The results could improve our understanding of trends in physical activity with respect to age and gender, providing a basis for public health monitoring and policy-making.

Association of step counts with cognitive function in apparently healthy middle-aged and older Japanese men

Background

Increasing physical activity may prevent cognitive decline. Previous studies primarily focused on older adults and used self-reported questionnaires to assess physical activity. We examined the relationship between step count, an objective measure of physical activity, and cognitive function in community-based middle-aged and older Japanese men.

Methods

The Shiga Epidemiological Study of Subclinical Atherosclerosis randomly recruited community-dwelling healthy men aged 40-79 years from Shiga, Japan, and measured their step counts over 7 consecutive days using a pedometer at baseline (2006-2008). Among men who returned for follow-up (2009-2014), we assessed their cognitive function using the Cognitive Abilities Screening Instrument (CASI) score. We restricted our analyses to those with valid 7-day average step counts at baseline and those who remained free of stroke at follow-up (n = 676). Using analysis of covariance, we calculated the adjusted means of the CASI score according to the quartiles of the average step counts.

Results

The mean (standard deviation) of age and unadjusted CASI score were 63.8 (9.1) years and 90.8 (5.8), respectively. The CASI score was elevated in higher quartiles of step counts (90.2, 90.4, 90.6, and 91.8 from the lowest to the highest quartile, respectively, [p for trend = 0.004]) in a model adjusted for age and education. Further adjustment for smoking, drinking, and other cardiovascular risk factors resulted in a similar pattern of association (p for trend = 0.005).

Conclusion

In apparently healthy middle-aged and older Japanese men, a greater 7-day average step count at baseline was associated with significantly higher cognitive function score.

Step-Based Metrics and Translations of Physical Activity Guidelines among Adults in the HCHS/SOL

PURPOSE

In a cross-sectional sample of US Hispanic/Latino adults, we aimed to describe step-based metric distributions, estimate their associations with activity counts and self-report, and calibrate step-based translations of current (2018) US physical activity (PA) guidelines, that is, ≥150 min·wk -1 moderate-to-vigorous PA (MVPA) from accelerometer counts and self-report.

METHODS

The Hispanic Community Health Study/Study of Latinos enrolled 16,415 Hispanic/Latino adults 18-74 yr from four US cities (2008-2011). Participants completed the Global PA Questionnaire and 1 wk of Actical accelerometer wear ( n = 12,528). Weighted medians were used to describe step-based metrics, and Spearman correlations estimated their relationships with count-based and self-reported PA indicators. Receiver operator characteristic curve analyses were used to examine the ability of each step-based metric to classify participants meeting PA guidelines.

RESULTS

Overall, US Hispanic/Latino adults accumulated medians of 6770 steps per day and 6, 18, 236, and 630 min·d -1 at ≥100, ≥70, 1-69, and 0 steps per minute, respectively. Count-based time in MVPA, light PA, and sedentary behavior were most strongly correlated ( rs = 0.79-0.85) with times ≥70, 1-69, and 0 steps per minute, respectively, whereas self-reported MVPA had similar correlations with steps per day and times ≥40 and ≥70 steps per minute ( rs = 0.28-0.29). Time ≥70 steps per minute had the greatest capacity to classify participants meeting PA guidelines with both measures of MVPA.

CONCLUSIONS

This study provides the first normative values (based on percentiles) of step-based metrics for US Hispanic/Latino adults, which can facilitate surveillance, program planning, research, and data interpretation. Our finding that PA guidelines corresponded to 6000-7000 steps per day or ~20 min·d -1 at ≥70 steps per minute with an Actical accelerometer can be considered alongside dose-response relationships with health outcomes to develop step-based recommendations that are consistent with and better communicate PA guidelines.

National Trends in Physical Activity Among Adults in South Korea Before and During the COVID-19 Pandemic, 2009-2021

Importance

There is a lack of comprehensive data on the association of the COVID-19 pandemic with the prevalence of physical activity in large-scale data sets.

Objective

To investigate long-term trends in physical activity using information from a nationally representative survey covering 2009 to 2021.

Design, Setting, and Participants

This general population-based and repeated cross-sectional study was conducted from 2009 to 2021 using the Korea Community Health Survey, a nationally representative survey in South Korea. Data from 2009 to 2021 for 2 748 585 Korean adults were obtained through a nationwide, large-scale, serial study. Data were analyzed from December 2022 through January 2023.

Exposure

COVID-19 pandemic onset.

Main Outcomes and Measures

The trend of sufficient aerobic physical activity was measured by prevalence and mean metabolic equivalent of task (MET) score based on World Health Organization physical activity guidelines and defined as 600 MET-min/wk or greater. The cross-sectional survey included age, sex, body mass index (BMI), region of residence, education level, income level, smoking status, alcohol consumption level, stress status, physical activity level, and history of diabetes, hypertension, and depression.

Results

Among 2 748 585 Korean adults (738 934 aged 50-64 years [29.1%] and 657 560 aged ≥65 years [25.9%]; 1 178 869 males [46.4%]), the prevalence of sufficient physical activity did not change significantly during the prepandemic period (β difference, 1.0; 95% CI, 0.6 to 1.4). During the pandemic, the prevalence of sufficient physical activity decreased significantly, from 36.0% (95% CI, 35.9% to 36.1%) in 2017 to 2019 to 30.0% (95% CI, 29.8% to 30.2%) in 2020 and 29.7% (95% CI, 29.5% to 29.9%) in 2021. Trends showed decreases in the prevalence of sufficient physical activity among older adults (ages ≥65 years; β difference, -16.4; 95% CI, -17.5 to -15.3) and younger adults (ages 19 to 29 years; β difference, -16.6; 95% CI, -18.1 to -15.0) during the pandemic. In particular, the trend of sufficient physical activity declined during the pandemic in females (β difference, -16.8; 95% CI, -17.6 to -16.0), individuals in urban residences (β difference, -21.2; 95% CI, -22.2 to -20.2), healthy participants (eg, those with normal BMI, 18.5 to 22.9: β difference,-12.5; 95% CI, -13.4 to -11.7), and individuals at increased risk of stress (eg, history of a depressive episode; β difference, -13.7; 95% CI, -19.1 to -8.4). Prevalence trends in mean MET score were similar to those in the main results; total mean MET score decreased from the 2017 to 2019 period (1579.1 MET-min/wk; 95% CI, 1567.5 to 1590.7 MET-min/wk) to the 2020 to 2021 period (1191.9 MET-min/wk; 95% CI, 1182.4 to 1201.4 MET-min/wk.

Conclusions and Relevance

This cross-sectional study found that the national prevalence of physical activity was stable or consistent before the pandemic period, with a marked decrease during the pandemic, particularly among healthy individuals and subgroups at increased risk of negative outcomes, including older adults, females, urban residents, and those with depressive episodes. Future studies may be needed to evaluate the association between the COVID-19 pandemic and changes in physical activity.

Promoting Stair Use is Possible by Displaying Signs, Even for Stairs of 80 or 105 Steps

Installing signs is known to be effective in encouraging people to use stairs instead of escalators. However, it has been reported that the effectiveness of such signs is diminished as the number of stairs increases, and no effect was reported at 44 steps. Thus, this study examined whether stair use could be promoted even with 80 or 105 steps by presenting specific numerical values for the health benefits of using stairs. At two universities with parallel escalators and stairs (105 and 80 steps, respectively), we installed signs stating, "Going up one flight of stairs increases your life span by 4 seconds." A one-week baseline period was followed by a one-week intervention using signs displayed to passersby. Follow-up data were also collected for one week immediately after removing the signs. Measurements were collected Monday through Friday from 7:30 to 9:15 a.m. The number of passersby was recorded by categorizing them into four attributes: male and female students, and male and female faculty/staff. A total of 25,065 observations (963 stair users vs. 24,102 escalator users) at University A and 25,677 observations (1020 stair users vs. 24,657 escalator users) at University B were recorded. Sign installation promoted stair use at University A (odds ratio [OR], 1.513; 95% confidence interval [CI], 1.307-1.752) and University B (OR, 1.221; 95% CI, 1.046-1.425). However, there was no effect of the sign installation on the population with attributes that had a high percentage of stair use prior to this study, implying that there is a ceiling effect on the effectiveness of such signs. The implication of the findings is that it is effective to provide detailed information to passersby on the health benefits of stair use for stairs with 80 or 105 steps.

Factors associated with changes in the objectively measured physical activity among Japanese adults: A longitudinal and dynamic panel data analysis

Factors associated with dynamic changes in the objectively measured physical activity have not been well understood. We aimed to 1) evaluate the longitudinal change in the physical activity trajectory according to sex which is associated with age and to 2) determine the factors associated with the dynamic change in physical activity-related variables across a wide age range among Japanese adults. This longitudinal prospective study included 689 Japanese adults (3914 measurements) aged 26-85 years, whose physical activity data in at least two surveys were available. Physical activity-related variables, such as intensity (inactive, light [LPA; 1.5 to 2.9 metabolic equivalents (METs)], moderate-to-vigorous [MVPA; ≥3.0 METs]), total energy expenditure (TEE), physical activity level (PAL), and step count, were evaluated using a validated triaxial accelerometer. Statistical analysis involved the latent growth curve models and random-effect panel data multivariate regression analysis. During a mean follow-up period of 6.8 years, physical activity was assessed an average of 5.1 times in men and 5.9 times in women. The profiles for the inactive time, LPA (only men), MVPA, step count, PAL, and TEE showed clear curvature, indicating an accelerated rate of change around the age of 70. In contrast, other variables exhibited minimal or no curvature over the age span. The MVPA trajectory was positively associated with alcohol consumption, hand grips, leg power, and trunk flexibility and negatively associated with age, local area, body mass index (BMI), comorbidity score, and heart rate over time. Our results indicated that the physical activity trajectory revealed clear curvature, accelerated rate of change around the age of 70, and determined physical health and fitness and BMI as dynamic factors associated with physical activity changes. These findings may be useful to help support populations to achieve and maintain the recommended level of physical activity.

Evaluation of pre-Games effects of the Tokyo 2020 Olympic Games on Japanese population-level physical activity: a time-series analysis

Background

The Olympic Games represent an opportunity to create a ‘physical activity legacy’ that promotes physical activity at the population level in the host nations and cities. However, previous studies showed little increase in population-level physical activity following the Olympics. The upsurge of public interest in sports and physical activity participation before the Olympics may diminish rapidly following the Games. We examined the pre-Games effects of the Olympics on Japanese population-level physical activity after the announcement of Tokyo’s successful bid for the 2020 Olympic and Paralympic Games in September 2013.

Methods

We used publicly available data from serial cross-sectional surveys conducted with nationally or regionally representative samples in Japan seven years before and after the announcement (from 2006–2020). The outcomes were 1) daily step counts and 2) exercise habit prevalence (≥ 30 min/day, ≥ 2 days/week, and over a year) from the National Health and Nutrition Surveys Japan (NHNS-J; 14 time points; aggregated data); and 3) sports participation (at least once a week) from the National Sports-Life Survey conducted every two years (NSLS; eight time points; individual-level data of 18,867 adults) and from the Public Opinion Survey on Sports Participation of Tokyo Residents (POSSP; eight time points; aggregated data). Age- and gender-adjusted regression models were used to estimate changes in the outcomes before and after the announcement.

Results

There were no significant pre-Games effects of the Olympics on national-level physical activity participation among Japanese adults. Sports participation (56.4% and 57.5%, respectively; P = 0.518), daily steps (6,535 and 6,686 steps/day; P = 0.353), and exercise habit (30.7% and 29.1%, P = 0.309) did not change significantly before and after the announcement. Although an increase in sports participation among Tokyo residents was not found in the NSLS (61.5% and 59.3%, P = 0.227), it was observed in the POSSP (49.1% and 57.7%, P = 0.019). Nonetheless, this increase might not be related to the pre-Games effects since the trend diminished following the announcement.

Conclusions

Population-level physical activity did not show significant changes until 2020. Realising the physical activity legacy of an Olympics may require strategic promotion and cross-agency partnership implementation in the pre- and post-event period.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12966-022-01332-x.

The Surveillance of Physical Activity, Sedentary Behavior, and Sleep: Protocol for the Development and Feasibility Evaluation of a Novel Measurement System

BACKGROUND

There is increasing recognition of the need for more comprehensive surveillance data, including information on physical activity of all intensities, sedentary behavior, and sleep. However, meeting this need poses significant challenges for current surveillance systems, which are mainly reliant on self-report.

OBJECTIVE

The primary objective of this project is to develop and evaluate the feasibility of a sensor-based system for use in the surveillance of physical activity, sedentary behavior, and sleep (SurPASS) at a national level in Denmark.

METHODS

The SurPASS project involves an international, multidisciplinary team of researchers collaborating with an industrial partner. The SurPASS system consists of (1) a thigh-worn accelerometer with Bluetooth connectivity, (2) a smartphone app, (3) an integrated back end, facilitating the automated upload, analysis, storage, and provision of individualized feedback in a manner compliant with European Union regulations on data privacy, and (4) an administrator web interface (web application) to monitor progress. The system development and evaluation will be performed in 3 phases. These phases will include gathering user input and specifications (phase 1), the iterative development, evaluation, and refinement of the system (phase 2), and the feasibility evaluation (phase 3).

RESULTS

The project started in September 2020 and completed phase 2 in February 2022. Phase 3 began in March 2022 and results will be made available in 2023.

CONCLUSIONS

If feasible, the SurPASS system could be a catalyst toward large-scale, sensor-based surveillance of physical activity, sedentary behavior, and sleep. It could also be adapted for cohort and interventional research, thus contributing to the generation of evidence for both interventions and public health policies and recommendations.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/35697.

Equivalency of four research-grade movement sensors to assess movement behaviors and its implications for population surveillance

the benefits of physical activity (PA) and sleep for health, accurate and objective population-based surveillance is important. Monitor-based surveillance has potential, but the main challenge is the need for replicable outcomes from different monitors. This study investigated the agreement of movement behavior outcomes assessed with four research-grade activity monitors (i.e., Movisens Move4, ActiGraph GT3X+, GENEActiv, and Axivity AX3) in adults. Twenty-three participants wore four monitors on the non-dominant wrist simultaneously for seven days. Open-source software (GGIR) was used to estimate the daily time in sedentary, light, moderate-to-vigorous PA (MVPA), and sleep (movement behaviors). The prevalence of participants meeting the PA and sleep recommendations were calculated from each monitor’s data. Outcomes were deemed equivalent between monitors if the absolute standardized difference and its 95% confidence intervals (CI_95%) fell within ± 0.2 standard deviations (SD) of the mean of the differences. The participants were mostly men (n = 14, 61%) and aged 36 (SD = 14) years. Pairwise confusion matrices showed that 83–87% of the daily time was equally classified into the movement categories by the different pairs of monitors. The between-monitor difference in MVPA ranged from 1 (CI_95%: − 6, 7) to 8 (CI_95%: 1, 15) min/day. Most of the PA and sleep metrics could be considered equivalent. The prevalence of participants meeting the PA and the sleep guidelines was 100% consistent across monitors (22 and 5 participants out of the 23, respectively). Our findings indicate that the various research-grade activity monitors investigated show high inter-instrument reliability with respect to sedentary, PA and sleep-related estimates when their raw data are processed in an identical manner. These findings may have important implications for advancement towards monitor-based PA and sleep surveillance systems.

Time Trends in Physical Activity Using Wearable Devices: A Systematic Review and Meta-analysis of Studies from 1995 to 2017

INTRODUCTION

Conflicting evidence exists on whether physical activity (PA) levels of humans have changed over the last quarter-century. The main objective of this study was to determine if there is evidence of time trends in PA, from cross-sectional studies that assessed PA at different time points using wearable devices (e.g., pedometers and accelerometers). A secondary objective was to quantify the rate of change in PA.

METHODS

A systematic literature review was conducted of English-language studies indexed in PubMed, SPORTDiscus, and Web of Science (1960-2020) using search terms (time OR temporal OR secular) AND trends AND (steps per day OR pedometer OR accelerometer OR MVPA). Subsequently, a meta-analytic approach was used to aggregate data from multiple studies and to examine specific factors (i.e., sex, age-group, sex and age-group, and PA metric).

RESULTS

Based on 16 peer-reviewed scientific studies conducted between 1995 and 2017, levels of ambulatory PA are trending downward in developed countries. Significant declines were seen in both males and females (P < 0.001) as well as in children (P = 0.020), adolescents (P < 0.001), and adults (P = 0.004). The average study duration was 9.4 yr (accelerometer studies, 5.3 yr; pedometer studies, 10.8 yr). For studies that assessed steps, the average change in PA was -1118 steps per day over the course of the study (P < 0.001), and adolescents had the greatest change in PA at -2278 steps per day (P < 0.001). Adolescents also had the steepest rate of change over time, expressed in steps per day per decade.

CONCLUSIONS

Evidence from studies conducted in eight developed nations over a 22-yr period indicates that PA levels have declined overall, especially in adolescents. This study emphasizes the need for continued research tracking time trends in PA using wearable devices.

Effect of a 1-year intervention comprising brief counselling sessions and low-dose physical activity recommendations in Japanese adults, and retention of the effect at 2 years: a randomized trial

Background

In an effort to increase people’s adherence to active lifestyles, contemporary physical activity (PA) guidelines now include low-dose PA.

Methods

PA was evaluated in 583 participants of the Nutritional and Physical Activity Intervention Study (NEXIS) cohort (30–65 years old); 349 inactive participants (MVPA, 2.7 ± 1.0 MET-h/day) were randomly assigned to the intervention or control groups, and 235 active participants participated in follow-up visits. The intervention aimed to increase MVPA and comprised five brief counseling sessions over 1 year. The 1-year target for the participant was increasing their step-count to 10,000 steps/d or +3000 steps/d, relative to the baseline score. The counseling sessions were designed to stimulate progressive changes in physical behaviors by recommendations promoting small and/or light-intensity bouts of PA. PA was measured at baseline, the end of the intervention, and 1 year after the intervention ended. Additionally, several nutrition, health, and fitness parameters were measured.

Results

Participants in the intervention group significantly increased their step-count from 8415 ± 1924 at baseline to 9493 ± 2575 at the end of the 1-year period. During the same period, MVPA significantly increased by 0.9 MET-h. The daily time spent in ≥ 3, ≥ 4 and ≥ 5 MET activities increased by 11, 6, and 3 min, respectively. This increase in PA remained observable 1 year after intervention concluded. The active group maintained higher physical activity levels throughout the two years. The intervention group showed smaller energy intakes at the end of the 2-year period. Significant correlations were noted between the 1-year change in MVPA and the change in resting heart rate (r =  − 0.22), and between the 2-year change in MVPA and the change in waist circumference (r =  − 0.08) and peak oxygen consumption capacity (r = 0.23) in the intervention group only.

Conclusions

A prolonged and progressive PA intervention promoting small bouts of light-to-moderate PA may be used in healthy, not-optimally-active people to increase PA beyond the strict period of the intervention. Further studies are necessary to understand whether low-dose PA messages can be effective in initiating a progressive increase toward larger amounts of PA.

Trial registration: Clinical Trials.gov, NCT00926744, retrospectively registered.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13102-021-00360-7.

Are Japanese Women Less Physically Active Than Men? Findings From the DOSANCO Health Study

BACKGROUND

Previous research has established that women accumulate less moderate-to-vigorous physical activity (MVPA) than men. To date, however, little is known about the gender differences in device-based activity patterns of sedentary behavior (SB) and light-intensity physical activity (LPA). We aimed to compare time spent in SB and different intensities of physical activity taking into account of co-dependence of time use domains.

METHODS

This cross-sectional study was conducted in Suttu town, Hokkaido, Japan. Data were analyzed from 634 Japanese adults (278 men, aged 19-92 years) who provided valid accelerometer (HJA-750C) data. Gender differences in activity behavior patterns were tested using multivariate analysis of covariance (MANCOVA) based on isometric log-ratio transformations of time use, adjusting for age. We also developed bootstrap percentile confidence intervals (CI) to support the interpretation of which behavior differed between genders.

RESULTS

Overall, participants had percent time spent in SB, LPA, MVPA during wearing time (mean, 14.8 hours) corresponding to 53.9%, 41.7%, and 4.4% of wearing time, respectively. Activity behavior patterns differed significantly between genders after controlling for time spent in all activities. Women spent relatively 13.3% (95% CI, 9.9-15.9%) less time in SB and 19.8% (95% CI, 14.9-24.6%) more time in LPA compared to men. The difference of time spent in MVPA was not statistically significant.

CONCLUSIONS

In contrast with previous studies, our findings suggest that Japanese women are more physically active than men when all intensities of activities are considered. Given the health benefits of LPA, evaluating only MVPA may disproportionately underestimate the level of physical activity of women.

Association of objectively measured daily physical activity and health utility to disease severity in chronic heart failure patients: A cross-sectional study

Background and aims

Physical activity (PA) levels are related to mortality and morbidity in patients with chronic heart failure (CHF). Health utility (HU), a very important cost-effectiveness analysis for health care and health status, is measured by several preference-based utility measures. This study aimed to evaluate the relation between PA and HU and the effect of disease severity on PA and HU in patients with CHF.

Methods

We enrolled 226 consecutive outpatients with CHF (mean age, 57.5 years; males, 79.6%) in this retrospective cross-sectional study. Patients were divided into three groups by NYHA class for classification of disease severity. Patient characteristics, average step count in steps/day, PA energy expenditure (PAEE) in kcal/day for 7 days as assessed by accelerometer, and HU assessed by Short Form-6D were compared between the groups.

Results

Average step count (r = 0.37, P < 0.01) and average PAEE (r = 0.36, P < 0.01) correlated positively with HU in all patients. Patients were classified into three groups by NYHA class: class I (n = 92), class II (n = 97), and class III (n = 37). Average step counts (7618.58, 6452.51, and 4225.63 steps/day, P < 0.001), average PAEE (244.65, 176.88, and 103.72 kcal/day, P < 0.001), and HU (0.68, 0.63, and 0.57, P < 0.001) respectively decreased with the increase in NYHA class (P < 0.001).

Conclusion

This study showed a significant relationship of daily PA and HU to disease severity in patients with CHF. Although causation cannot be determined from this study, these results suggest that PA and HU may provide important information related to the severity of disease in patients with CHF.

Developing a Study Protocol for Analyzing Policies to Promote Physical Activity Among Urban Middle-Aged People: A Case of a Metropolitan City in Iran

Background: The level of physical activity (PA) among middle-aged Iranians is less than optimal. This study will be carried out to analyze and recommend policy options to promote PA among urban middle-aged adults in Tabriz, one of the metropolitan cities in Iran. Methods: This multi-method policy analysis study will include the following four phases: First, a qualitative content analysis to explore the reasons for lack of PA. Second, a comparative study of successful PA programs and policies in Iran and other similar developing countries. Third, a qualitative thematic analysis based on the policy triangle to analyses PA promotion policies using the key informants’ views. Fourth, analysis and prioritizing the policy options suggested by a panel of experts using the analytical hierarchy process (AHP) techniques. Conclusions: Prospective policy analysis promises the systematic process of selecting potentially effective policy options to promote PA in metropolitan settings of developing countries. The results of this study will provide a comprehensive vision of the most appropriate policy options based on the criteria of acceptability, effectiveness, and feasibility for addressing PA at the local and national levels. Considerations on the challenges of PA policymaking cycle and the barriers to the implementation of current policies in the Iranian context will also be identified.

An evidence-based assessment of the impact of the Olympic Games on population levels of physical activity

Pre-Olympic Games predictions commonly include an increase in population-based physical activity in the host city, as often stated in the bid, but the post-Olympic Games effects on physical activity have not been summarised. In this Series paper, we aim to do the following: examine mentions of a physical activity legacy in pre-Olympic bid documentation; analyse existing physical activity surveillance data collected before, during, and after the Olympic Games in hosting areas around the world; and evaluate Google Trends data surrounding the London 2012 Olympic Games as a case study of community interest in the topic of exercise during the time of the Olympic Games. Before 2007, little mention of physical activity was made in pre-Olympic Games documentation, but, after that, most documents had targets for population physical activity or sports participation. The synthesis of available surveillance data indicates that there was no change in the prevalence of physical activity or sports participation, except for the 2008 Summer Olympics in Beijing and the 1998 Winter Olympics in Nagano; although, the increase in participation in Nagano might not be attributable to the Olympic Games since there was no change in participation in winter sports. The Google Trends data showed an acute spike in searches with the term "Olympic" immediately associated with the London Olympic Games period and showed a sustained peri-Olympic increase in searches with the term "exercise". By themselves, the Olympic Games have not improved population-wide physical activity but might be an important missed public health opportunity. Such a legacy will require strategic planning and partnerships across the International Olympic Committee and the Olympic, sport, and public health agencies and a thorough evaluation framework implemented throughout the pre-Olympic Games and post-Olympic Games period in the host country.

How can global physical activity surveillance adapt to evolving physical activity guidelines? Needs, challenges and future directions

Public health guidelines on physical activity (PA) establish national policy agendas and provide the basis for setting goals and targets. Advances in measurement and resulting new scientific findings lead to evolution of PA guidelines. PA surveillance serves to track compliance with national guidelines, usually expressed as the proportion of the population ‘meeting’ the main quantitative guidelines. The WHO recently completed a process to review and update the global PA guidelines. Changes to the guidelines, such as removal of a 10-min bout criterion, pose challenges for PA surveillance. We review the evolution of PA guidelines and associated surveillance methods and explore implications of the updated guidelines for changes in population surveillance and opportunities for technological approaches to PA to enhance surveillance.

Neighborhood Environmental Factors and Physical Activity Status among Rural Older Adults in Japan

(1) Background: Although several neighborhood environmental factors have been identified to be associated with older adults’ physical activity, little research has been done in rural areas where the population is aging. This study aimed to investigate neighborhood environmental factors and the longitudinal change of physical activity status among rural older adults in Japan. (2) Methods: The study included 2211 older adults, aged over 60 years, residing in three municipalities in Shimane prefecture and participating at least twice in annual health checkups between 2010 and 2019. Physical activity was identified based on self-report. Hilliness, bus stop density, intersection density, residential density, and distance to a community center were calculated for each subject. Hazard ratios for the incidence of physical inactivity were estimated using Cox proportional hazards models. (3) Results: We found that 994 (45%) of the study subjects became physically inactive during the follow-up. Those living far from a community center had a lower risk of becoming physically inactive compared to those living close to a community center. When the analysis was stratified by residential municipality, this association remained in Ohnan town. Those living in hilly areas had a higher risk of becoming physically inactive in Okinoshima town. (4) Conclusions: The impact of neighborhood environmental factors on older adults’ physical activity status might differ by region possibly due to different terrain and local lifestyles.

Older Adults' Daily Step Counts and Time in Sedentary Behavior and Different Intensities of Physical Activity

Background

Daily step count is the simplest measure of physical activity. However, little is known about how daily step count related to time spent in different intensities of physical activity (PA) and sedentary behavior (SB).

Methods

These cross-sectional data were derived from 450 older Japanese adults (56.7% men; mean age, 74.3 years) who were randomly selected from three communities and responded a survey. Daily step count and time spent in moderate-to-vigorous PA (MVPA), light-intensity PA (LPA), and SB were measured using a validated wearable technology (HJA-350IT). Associations of daily step count with time spent in measured behaviors were examined using linear regression models with isometric log-ratio transformations of time-use composition, adjusting for gender, age, and residential area.

Results

Participants averaged 5,412 (standard deviation, 2,878) steps/d and accumulated MVPA, LPA, and SB corresponding to 4.0%, 34.8%, and 61.2% of daily waking time, respectively. Daily step count significantly increased with increase in time spent in MVPA relative to other behaviors (ie, LPA and SB) and in the ratio of LPA to SB after allowing for MVPA. After stratification, daily step count was significantly related to the ratio of LPA to SB in those taking <5,000 steps/d, but not in those taking 5,000–7,499 and ≥7,500 steps/d.

Conclusions

Higher daily step count can be an indicator of not only larger relative contribution of time spent in MVPA, but also higher ratio between LPA and SB, particularly among those who are the least physically active.

Objectively Measured Daily Step Counts and Prevalence of Frailty in 3,616 Older Adults

OBJECTIVES

Although previous studies have reported lower mortality and morbidity in people with higher daily step counts, the association between frailty and objectively measured step counts has not been evaluated well. We investigated the association between step counts and prevalence of frailty in community‐dwelling older adults.

DESIGN

A cross‐sectional study.

SETTING

The Kyoto‐Kameoka study in Japan.

PARTICIPANTS

We used data of 3,616 Japanese older adults, aged 65 years or older, with valid daily step count data, obtained by an accelerometer‐based pedometer.

MEASUREMENTS

The step count during 4 or more days was objectively obtained by a validated triaxial accelerometer. Participants were classified by quartiles (Qs) based on their step counts. Frailty was defined using the Fried phenotype (FP) model and the Kihon Checklist (KCL). We evaluated the association between prevalence of frailty and step counts using multivariate logistic regression and the restricted cubic spline model.

RESULTS

Mean step counts across low‐to‐high Qs of distribution were 1,759, 2,988, 4,377, and 7,200 steps/day, respectively. The prevalence of frailty, as defined by the FP model and KCL, was 11.3% and 26.8%, respectively. After adjusting for confounders, there was a negative association between the odds ratio (OR) and prevalence of frailty, as defined by the FP model among people with higher step counts (Q1: reference; Q2: OR = 0.73; 95% confidence interval (CI) = 0.56–0.96; Q3: OR = 0.56; 95% CI = 0.42–0.76; and Q4: OR = 0.41; 95% CI = 0.30–0.57; P for trend <.001). The mean step count of the population was 4,081. The OR of frailty for a 1,000‐steps/day increment was 0.74 (95% CI = 0.58–0.91) and 0.85 (95% CI = 0.72–0.97) below 4,000 steps and above 4,000 steps, respectively. In the spline model, this relationship was similar between the FP model and KCL.

CONCLUSION

These findings suggest that slightly increasing the current step count, as by 1,000 steps/day (about 10 minutes of activity), may potentially prevent frailty. J Am Geriatr Soc 68:2310–2318, 2020.