Potential effect of ketamine in treatment for dextromethorphan use disorder exploding in Japanese young population.

In Japan, the landscape of clinical practice for substance use disorder is changing significantly, primarily due to an increase in patients using over-the-counter drugs. A major concern is the rising number of patients misusing dextromethorphan (DXM). These patients with DXM use disorders often have severe trauma-related and mood symptoms, and therefore try to cope with those symptoms by self-medicating with DXM. In this article, we propose that ketamine, which has similar psychopharmacological effects to DXM, may be a useful alternative pharmacological treatment for these patients.

Hemodynamics of short-duration light-intensity physical exercise in the prefrontal cortex of children: a functional near-infrared spectroscopy study.

Identifying the types of exercise that enhance cerebral blood flow is crucial for developing exercise programs that enhance cognitive function. Nevertheless, few studies have explored the amount of light-intensity, short-duration exercises that individuals can easily perform on cerebral blood flow, particularly in children. We examined the effects of these exercises on the hemodynamics of the prefrontal cortex (PFC) using functional near-infrared spectroscopy. Participants comprised 41 children (aged 12.1 ± 1.5 years, 37% female) who engaged in seven light-intensity exercises, with each movement performed in two patterns lasting 10 or 20 s. Changes in oxygenated hemoglobin (oxy-Hb) levels at rest and during exercise were compared using analysis of covariance, with sex and age as covariates. Significant increases in oxy-Hb were observed in multiple regions of the PFC during all forms of exercise (including dynamic and twist stretching [66.6%, 8/12 regions, η2 = 0.07-0.27], hand and finger movements [75.0%, 9/12 regions, η2 = 0.07-0.16], and balance exercises (100.0%, 6/6 regions, η2 = 0.13-0.25]), except for static stretching with monotonic movements. This study implies that short-duration, light-intensity exercises, provided that they entail a certain degree of cognitive and/or physical demands, can activate the PFC and increase blood flow.

Social role of the 'Bow-Wow Patrol' in urban areas of Japan: a qualitative study.

The 'Bow-Wow Patrol (BWP)', established to avert local crime by encouraging dog walking, may help build social relationships among individuals through dog walking. However, details of its social influence remain unclear. Thus, this study aimed to elucidate the social roles of BWP in the urban areas of Japan. A total of 18 BWP organisation members from two Tokyo municipalities were recruited using snowball sampling between November 2021 and July 2022. In an interview, participants were asked about their perceptions of changes in their social relationships through the BWP. Qualitative content analysis was conducted after text mining using the KH Coder software. The mean age of the participants was 63.9 years, and 83.3% engaged in BWP 7 days a week. The content analysis revealed six social roles of the BWP: establishment of social networks with schools as the centre, establishment of loose networks inside and outside the BWP organization, enhancement of a sense of trust among neighbours, enhancement of a sense of trust in communities, norms of reciprocity among dog owners, and dog and owner characteristics. This study found that the BWP in urban Japan strengthens social cohesion and expands social networks among dog walkers, encouraging them to continue walking.

Healthy Japanese dietary pattern is associated with slower biological aging in older men: WASEDA'S health study.

Aging is the greatest risk factor for numerous diseases and mortality, and establishing geroprotective interventions targeting aging is required. Previous studies have suggested that healthy dietary patterns, such as the Mediterranean diet, are associated with delayed biological aging; however, these associations depend on nationality and sex. Therefore, this study aimed to investigate the relationship between dietary patterns identified through principal component analysis and biological aging in older men of Japan, one of the countries with the longest life expectancies. Principal component analysis identified two dietary patterns: a healthy Japanese dietary pattern and a Western-style dietary pattern. Eight epigenetic clocks, some of the most accurate aging biomarkers, were identified using DNA methylation data from whole-blood samples. Correlation analyses revealed that healthy Japanese dietary patterns were significantly negatively or positively correlated with multiple epigenetic age accelerations (AgeAccel), including AgeAccelGrim, FitAgeAccel, and age-adjusted DNAm-based telomere length (DNAmTLAdjAge). Conversely, the Western-style dietary pattern was observed not to correlate significantly with any of the examined AgeAccels or age-adjusted values. After adjusting for covariates, the healthy Japanese dietary pattern remained significantly positively correlated with DNAmTLAdjAge. Regression analysis showed that healthy Japanese dietary pattern contributed less to epigenetic age acceleration than smoking status. These findings suggest that a Western-style dietary pattern may not be associated with biological aging, whereas a healthy Japanese dietary pattern is associated with delayed biological aging in older Japanese men. Our findings provide evidence that healthy dietary patterns may have mild beneficial effects on delayed biological aging in older Japanese men.

Efficacy of hard gummy candy chewing in improving masticatory function in Japanese children aged 6-12 years: a clinical trial.

OBJECTIVES: Japanese children have been shown to exhibit decreased masticatory function; however, limited evidence is available regarding the efficacy of certain food items in improving this issue. Therefore, this study examined the effects of chewing hard gummy candy on the masticatory function of Japanese children aged 6-12 years. METHODS: The study included 26 participants (10 boys and 16 girls; mean age ± standard error = 9.3 ± 0.3 years) who were asked to chew hard gummy candy twice daily for 4 weeks at home. The lip-closing force, occlusal force, and masticatory performance of the participants were recorded before commencement (T1), 4 weeks after commencement (T2), and 4 weeks after completion (T3) of the training. Statistical analyses were performed using the Wilcoxon rank-sum test or the Wilcoxon signed-rank test with Bonferroni correction. RESULTS: No correlation was observed between masticatory function and sex at T1. The lip-closing and right occlusal forces increased significantly after 4 weeks of exercise, and the effects persisted for another 4 weeks after completion. The masticatory performance also improved after training, although these effects did not persist and deteriorated substantially 4 weeks after completion of the training. CONCLUSIONS: Habitual mastication training using hard gummy candy markedly enhances masticatory function (e.g., lip-closing force, occlusal force, and masticatory performance) in Japanese children.

Polygenic Risk Score, Cardiorespiratory Fitness, and Cardiometabolic Risk Factors: WASEDA'S Health Study.

PURPOSE: This study estimated an individual's genetic liability to cardiometabolic risk factors by polygenic risk score (PRS) construction and examined whether high cardiorespiratory fitness (CRF) modifies the association between PRS and cardiometabolic risk factors. METHODS: This cross-sectional study enrolled 1,296 Japanese adults aged ≥40 years. The PRS for each cardiometabolic trait (blood lipids, glucose, hypertension, and obesity) was calculated using the LDpred2 and clumping and thresholding methods. Participants were divided into low-, intermediate-, and high-PRS groups according to PRS tertiles for each trait. CRF was quantified as peak oxygen uptake (VO 2 peak) per kg body weight. Participants were divided into low-, intermediate-, and high-CRF groups according to the tertile VO 2 peak value. RESULTS: Linear regression analysis revealed a significant interaction between PRS for triglyceride (PRS TG ) and CRF groups on serum TG levels regardless of the PRS calculation method, and attenuated the association between PRS TG and TG levels in the high-CRF group. Logistic regression analysis revealed a significant sub-additive interaction between LDpred2 PRS TG and CRF on the prevalence of high TG, indicating that high CRF attenuated the genetic predisposition to high TG. Furthermore, a significant sub-additive interaction between PRS for body mass index and CRF on obesity was detected regardless of the PRS calculation method. These significant interaction effects on high TG and obesity were diminished in the sensitivity analysis using VO 2 peak per kg fat-free mass as the CRF index. Effects of PRSs for other cardiometabolic traits were not significantly attenuated in the high-CRF group regardless of PRS calculation methods. CONCLUSIONS: The findings of the present study suggest that individuals with high CRF overcome the genetic predisposition to high TG levels and obesity.

Chronotype and emotional/behavioral problems mediate the association between leisure screen time and academic achievement in children.

Leisure screen time is associated with poor academic achievement; however, the mechanism underlying this relationship is unclear. Chronotypes and emotional/behavioral problems may be linked to this association. This study aimed to examine the associations between leisure screen time, chronotype, emotional/behavioral problems, and academic achievement using mediation analysis. A total of 113 children aged 9-12 years participated in this study. All participants were assessed for leisure screen time, chronotype, emotional/behavioral problems, and academic achievement. Leisure screen time was evaluated using a self-reported questionnaire. Chronotypes were measured using The Japanese Children's Chronotype Questionnaire, and the morningness/eveningness (M/E) score was calculated. Emotional/behavioral problems were assessed using The Japanese Strengths and Difficulties Questionnaire, and the total difficulties score (TDS) was calculated. Academic achievement was assessed by the homeroom teacher for each of the seven school subjects. Partial correlation analysis adjusted for grade, sex, and sleep duration indicated that leisure screen time was associated with M/E scores and academic achievement (p < 0.05). There was a positive association between M/E score and TDS (p < 0.05) and a negative association between TDS and academic achievement (p < 0.05). A mediation analysis adjusted for grade, sex, and sleep duration was performed. There was a significant total effect of leisure screen time on academic achievement (p < 0.05). Additionally, the M/E score and TDS significantly mediated the association between leisure screen time and academic achievement (p < 0.05). Our findings suggest that the serial path between chronotype and emotional/behavioral problems weakly but significantly mediates the association of leisure screen time with academic achievement.

Associations between cardiorespiratory fitness and lifestyle-related factors with DNA methylation-based ageing clocks in older men: WASEDA'S Health Study.

DNA methylation-based age estimators (DNAm ageing clocks) are currently one of the most promising biomarkers for predicting biological age. However, the relationships between cardiorespiratory fitness (CRF), measured directly by expiratory gas analysis, and DNAm ageing clocks are largely unknown. We investigated the relationships between CRF and the age-adjusted value from the residuals of the regression of DNAm ageing clock to chronological age (DNAmAgeAcceleration: DNAmAgeAccel) and attempted to determine the relative contribution of CRF to DNAmAgeAccel in the presence of other lifestyle factors. DNA samples from 144 Japanese men aged 65-72 years were used to appraise first- (i.e., DNAmHorvath and DNAmHannum) and second- (i.e., DNAmPhenoAge, DNAmGrimAge, and DNAmFitAge) generation DNAm ageing clocks. Various surveys and measurements were conducted, including physical fitness, body composition, blood biochemical parameters, nutrient intake, smoking, alcohol consumption, disease status, sleep status, and chronotype. Both oxygen uptake at ventilatory threshold (VO2 /kg at VT) and peak oxygen uptake (VO2 /kg at Peak) showed a significant negative correlation with GrimAgeAccel, even after adjustments for chronological age and smoking and drinking status. Notably, VO2 /kg at VT and VO2 /kg at Peak above the reference value were also associated with delayed GrimAgeAccel. Multiple regression analysis showed that calf circumference, serum triglyceride, carbohydrate intake, and smoking status, rather than CRF, contributed more to GrimAgeAccel and FitAgeAccel. In conclusion, although the contribution of CRF to GrimAgeAccel and FitAgeAccel is relatively low compared to lifestyle-related factors such as smoking, the results suggest that the maintenance of CRF is associated with delayed biological ageing in older men.

Appropriately Addressing Too Much Sitting as a Public Health Issue: Content Analysis of Coverage in the Five Major National Japanese Newspapers.

Recent international public health guidelines now address reducing and breaking up time spent sitting (sedentary behavior). Japanese people spend considerable time sitting in workplaces and other contexts. With potential future public health guidelines in Japan, there is the need for greater public awareness of the importance of reducing sedentary time and of practical ways to do so. From the five major Japanese national newspapers, articles on sedentary behavior published between 2000 and 2021 were identified and coded for content analysis, including the main topic of the article, population group, sedentary behavior context or domain, health outcome, and solutions for reducing sedentary time. There were 53 articles identified, with sedentary behavior being the main topic in 22; workers as a population group appeared in 20 articles and workplaces as a domain in 22. More than 70% mentioned health influences, but fewer than 60% mentioned solutions. Further to informing the public about adverse health influences and consequences for workers and workplaces, there is also the need for improved coverage of the broader benefits of reducing sitting time, sedentary behavior among older adults and children, sitting in all aspects of daily life, and, importantly, considering public health guidelines and solutions for reducing prolonged sitting.

Which is More Effective and Safer? Comparison of Propensity Score-Matched Microhook Ab Interno Trabeculotomy and iStent Inject.

INTRODUCTION: The purpose of this study was to compare the surgical outcomes between ab interno trabeculotomy (LOT) and iStent inject W implantation (iStent) both combined with cataract surgery, matching the background factors including age, intraocular pressure (IOP), medication score, central corneal thickness (CCT), and axial length. METHODS: A total of 100 eyes from 75/79 patients with primary open-angle glaucoma were included in the LOT/iStent groups. The background factors were matched between the two groups using the propensity score. RESULTS: There were no significant differences in age, IOP, medication score, CCT, and axial length, preoperatively. The postoperative medication scores were 1.3 ± 1.2 and 1.2 ± 1.2 in the LOT and iStent groups. The postoperative IOPs were 12.8 ± 2.8 and 13.1 ± 2.4 mmHg in the LOT and iStent groups, respectively. The changes in the medication score were - 0.64 ± 1.4 and - 0.44 ± 1.6 in the LOT and iStent groups, respectively. The changes in the IOP were - 2.1 ± 3.3 and - 1.5 ± 3.0 mmHg in the LOT and iStent groups, respectively. These values were not significantly different between the two groups. The postoperative IOP and changes in the IOP were significantly associated with preoperative IOP and CCT. There was no significant difference in the occurrence of postoperative complications (hyphema, 11.0% and 6.0%, and transient ocular hypertension, 8.0% and 5.0%, in the LOT and iStent groups, respectively). CONCLUSION: LOT and iStent have similar surgical outcomes with sufficient safety. Postoperative IOP was significantly associated with preoperative IOP and CCT in both groups.

Time Course of Priming Effect of TF Inducers on Synergistic TF Expression and Intra-Cellular Gap Formation of Human Vascular Endothelial Cells via the Extrinsic Coagulation Cascade.

Chronic spontaneous urticaria (CSU) is characterized by daily recurring wheal and flare with itch for more than 6 weeks. The extrinsic coagulation system has been shown to be activated in correlation with CSU severity. We have reported that tissue factor (TF), a trigger of the extrinsic coagulation cascade, is synergistically expressed on vascular endothelial cells by simultaneous stimulation with TF inducers (TFI), followed by activation of the extrinsic coagulation cascade and hyper permeability in vitro. However, vascular endothelial cells are not likely to be simultaneously stimulated by multiple TFIs under physiological conditions. Therefore, in order to know whether sequential, rather than simultaneous, stimuli with interval may induce synergistic activation of TF, we investigated the time course of the priming effects of each TFI for synergistic TF expression in vascular endothelial cells (HUVECs). We stimulated HUVECs with a TFI (first stimulation) and then stimulated cells with another TFI at indicated time points (second stimulation) and detected TF expression and activity. The TF expression induced by simultaneous stimulation diminished in a few hours. However, both synergistic enhancement of TF expression and activation level of the coagulation cascade were detected even when the second stimulation was added 18 or 22 h after the first stimulation. Thus, the priming effect of TFI for synergistic TF expression may persist for a half day or longer.

Activity diversity is associated with the prevention of frailty in community-dwelling older adults: The Otassha Study.

Introduction: A prior study showed an association between diversity in daily activities (type, frequency, evenness) and frailty in older adults. However, the causality of this relationship is unclear. Therefore, this study aimed to clarify the relationship between activity diversity and frailty through a 2-year longitudinal study conducted among community-dwelling older adults. Methods: We evaluated data from the 2018 and 2020 waves of the Otassha Study. Frailty was assessed using the Cardiovascular Health Study criteria, with pre-frail and frail participants defined as frail and the other participants categorized into the robust group. We enrolled a total of 207 participants who were not frail at baseline. Activity type, frequency, and evenness scores were calculated using an Activity Diversity Questionnaire. The association between each activity diversity score and the incidence of frailty was evaluated using logistic regression modeling (each diversity score was entered the model after Z-transformation). Results: Of the 207 enrolled participants (median age, 73 years; age range, 65-91 years; 60.4% women), 64 (30.9%) had incident frailty during the follow-up period. A logistic regression analysis adjusting for sociodemographic and psychosomatic factors revealed odds ratios for activity type and evenness scores of 0.64 and 0.61, respectively (P < 0.05). These factors were significantly associated with the incidence of frailty. Discussion: Activity type and evenness (except frequency) within daily activities were predictors of frailty during 2 years of follow-up. Engagement in diverse activities appears to be more effective in preventing frailty than does engagement in a few activities.

Sedentary behaviour and sleep quality.

High-quality sleep is an important factor in sustaining health and improving well-being. Previous evidence has demonstrated the positive associations between increased physical activity and reduced sedentary behaviour (SB) with sleep quality. The substitutional relationships between SB, light-intensity physical activity (LPA), and moderate-to-vigorous physical activity (MVPA) need to be considered when examining how a particular behaviour may impact sleep quality. No studies, to our knowledge, have explored these substitutional relationships in middle-aged adulthood. Using an isotemporal substitution approach, this study examined the associations of replacing sedentary time with physical activity on sleep quality measures in a sample of middle-aged adults in Japan. Data from 683 adults aged 40-64 living in Japan were used. The average daily time spent in SB, LPA, and MVPA was objectively assessed by accelerometers. Two self-reported sleep quality measures were obtained using questionnaires, including rest by sleep and sleep quality. Multivariable linear regression models were used to assess the associations of SB, LPA, and MVPA with the sleep quality measures stratified by gender. We found that each 60 min unit of SB or LPA replaced with MVPA was favourably associated with rest by sleep among women (ß = 0.16, 95% CI 0.07, 0.28, p < 0.001; ß = 0.18, 95% CI 0.07, 0.32, p < 0.05, respectively). There were no significant associations between SB, LPA, and MVPA with sleep measures in men across all three models. These findings indicate that higher MVPA has a positive association with sleep quality in middle-aged women.

Coffee consumption and skeletal muscle mass: WASEDA'S Health Study.

Few studies have examined the association between coffee consumption and muscle mass; their results are conflicting. Therefore, we examined the association between coffee consumption and low muscle mass prevalence. We also performed an exploratory investigation of the potential effect modification by demographic, health status-related and physical activity-related covariates. This cross-sectional study included 2085 adults aged 40-87 years. The frequency of coffee consumption was assessed using a self-administered questionnaire. Muscle mass was assessed as appendicular skeletal muscle mass/height2 using a multifrequency bioelectrical impedance analyser. We defined low muscle mass using cut-offs recommended by the Asian Working Group for Sarcopenia. Multivariable-adjusted OR for low muscle mass prevalence were estimated using a logistic regression model. The prevalence of low muscle mass was 5·4 % (n 113). Compared with the lowest coffee consumption group (< 1 cup/week), the multivariable-adjusted OR (95 % CI) of low muscle mass prevalence were 0·62 (0·30, 1·29) for 1-3 cups/week, 0·53 (0·29, 0·96) for 4-6 cups/week or 1 cup/d and 0·28 (0·15, 0·53) for ≥ 2 cups/d (P for trend < 0·001). There were no significant interactions among the various covariates after Bonferroni correction. In conclusion, coffee consumption may be inversely associated with low muscle mass prevalence.

Physical therapist-delivered acceptance and commitment therapy and exercise for older outpatients with knee osteoarthritis: a pilot randomized controlled trial.

[Purpose] In this pilot study, we investigated the effectiveness of physical therapist-delivered acceptance and commitment therapy in older outpatients with knee osteoarthritis and chronic pain. [Participants and Methods] This single-center, open-label, parallel-group pilot randomized controlled trial included 30 patients assigned to the physical therapist-delivered acceptance and commitment therapy group (n=15) and the usual care physical therapy-only group (n=15). Both treatments were administered once a week for 8 weeks. Evaluation was performed 4 weeks before intervention, pre-intervention, post-intervention, and 4 weeks after intervention. The primary outcome was diagnosis of a physical disability, and secondary outcomes included psychological inflexibility, pain intensity, anxiety, depression, physical function, and objectively measured physical activity. [Results] Physical therapist-delivered acceptance and commitment therapy had a limited effect on physical disability, although we observed a favorable tendency. With regard to secondary outcomes, physical therapist-delivered acceptance and commitment therapy did not show significant effects. Notably, 15 patients withdrew from this study and 6 were diagnosed with coronavirus disease. [Conclusion] Physical therapist-delivered acceptance and commitment therapy did not appear to show significant effects in the present study. It is necessary to correct these issues in this study, and future studies are warranted to investigate the effects of this therapy.

The relationships between parents' and children's screen times on body mass index: a cross-sectional path analysis.

BACKGROUND: Understanding factors contributing to an individual reducing screen time is essential for promoting a healthy weight. Parents' behavior affects children by influencing their daily decision-making through modeling, rules or restrictions, social support, and co-participation. We examined how the direct and indirect effects of parents' and children's behaviors regarding screen time influenced body mass index (BMI) among Japanese elementary school children. METHODS: We included 283 Japanese children, one child per household, aged 6-12 years, who were randomly selected from resident registries of two cities. The questionnaires were completed by children and their mothers and fathers. Screen time and sociodemographic attributes, including sex, age, employment status, height, and weight, were assessed using a mail-based survey. Path analyses were conducted to determine associations among children's, fathers', and mothers' variables. It was hypothesized that after controlling for household income and children's sex and age, mothers' and fathers' screen time on weekdays and weekends would be related to children's weekdays and weekend screen time, respectively. In addition, we hypothesized that children's weekday and weekend screen time was related to children's BMI. RESULTS: Both fathers' and mothers' weekday screen times were associated with children's weekday and weekend screen times. BMI was affected by children's weekday screen time (0.117). The path coefficients for the indirect effects of mothers' and fathers' screen time on children's BMI through children's weekday screen time were 0.016 from the fathers' weekday screen time and 0.024 from the mothers' weekday screen time (GFI = .980, AGFI = .953, RMSEA = .030, AIC = 93.030). CONCLUSIONS: Both fathers' and mothers' weekday screen times indirectly affected children's BMI through children's weekday screen time among Japanese elementary school children. The strongest indirect effects could be seen by examining the paths of a mother's weekday screen time through children's screen time to BMI. Mothers who spend much time with their children are role models, and their behavior could affect the child's behavior. The findings imply that intervention strategies to reduce screen time in children should also focus on modeling the mothers' behavior.

Correlates of domain-specific sedentary behaviors and objectively assessed sedentary time among elementary school children.

Understanding the correlates of sedentary behavior among children is essential in developing effective interventions to reduce sitting time in this vulnerable population. This study aimed to identify correlates of domain-specific sedentary behaviors and objectively assessed sedentary time among a sample of children in Japan. Data from 343 children (aged 6-12 years) living in Japan were used. Domain-specific sedentary behaviors were assessed using a questionnaire. Total sedentary time was estimated using hip-worn accelerometers. Twenty-two potential correlates across five categories (parental characteristics, household indoor environment, residential neighborhood environment, school environment, and school neighborhood environment) were included. Multivariable linear regression models were used to identify correlates of domain-specific sedentary behaviors and objectively assessed sedentary time. Eight correlates were significantly associated with children's domain-specific sedentary behaviors: mother's and father's age, mother's educational level, having a video/DVD recorder/player, having a video console, having a TV one's own room, home's Walk Score®, and pedestrian/cycling safety. No significant associations were found between potential correlates and accelerometer-based total sedentary time. These findings highlight that strategies to reduce children's sedentary time should consider the context of these behaviors. For example, urban design attributes such as perceived pedestrian and cycling safety can be improved to reduce children's car sitting time.

Basophils activation of patients with chronic spontaneous urticaria in response to C5a despite failure to respond to IgE-mediated stimuli.

Urticaria is characterized by the occurrence of wheals and flares in response to vasoactive mediators, such as histamine. Various studies have suggested the involvement of basophils in the pathogenesis of chronic spontaneous urticaria (CSU). However, histamine release from peripheral basophils in response to stimuli acting on the high affinity IgE receptor (FcϵRI) is impaired in many patients with CSU (non/low responders). We previously demonstrated that tissue factor (TF)s expressed on vascular endothelial cells in response to a combination of various stimuli, such as that of histamine and lipopolysaccharide (LPS), activates the extrinsic coagulation pathway and produces anaphylatoxin, complement 5a (C5a), which then activates basophils and mast cells via the C5a receptor (C5aR). We have revealed that histamine release was induced in response to C5a and formyl-l-methionyl-l-leucyl-l-phenylalanine (fMLP), regardless of the response to anti-IgE antibody, the reduced numbers of basophils and severity of urticaria. Moreover, we found that spontaneous release of histamine ex vivo from basophils of patients with CSU is higher than that from healthy individuals. These results suggest that basophils and the complement system, which could be activated by coagulation factors, may play a critical role in the pathogenesis of CSU, especially in cases refractory to treatment involving the IgE/FcϵRI pathway.

Timing and intensity of physical activity and late sleeping habits among children in Japan.

Background: Little is known about what timing and intensity of physical activity (PA) are beneficial to preventing children's late sleeping habits. We investigated the association between timing and intensity of PA and late sleeping habits among Japanese children. Methods: The amount of PA on a weekday (light (>1.5 to <3.0 metabolic equivalents [METs]); moderate (3.0 to <6.0 METs); and vigorous (6.0 to <20.0 METs) was measured for the whole day, before school, during school, and after school, using accelerometers for population-based fourth-grade elementary school and eighth graders for 7 consecutive days between September and December 2018. Late sleeping habit (going to bed after 10 p.m. for fourth graders and after 11 p.m. for eighth graders) was assessed by questionnaires. The data of 229 fourth graders and 182 eighth graders were analyzed with Poisson regression adjusted for grade, gender, household income, body mass index (BMI), belonging to a sports club, wake-up time on weekdays, and PAs with different intensities. Results: Total PA was not associated with late sleeping habits. Light-intensity PA before school was protectively associated with late sleeping habits (prevalence ratio [PR]: 0.82, 95% confidence interval [CI]: 0.68, 0.99) while PA at school or after school was not. Conclusion: Light-intensity PA before school may enhance the earlier bedtime of children.

Factors promoting collaboration between community sports leaders and guardians in urban areas of Japan: A cross-sectional study.

Background: Community sports leaders (CSLs) are expected to play an important role in promoting regional sports in Japan. Increased opportunities for CSLs to work in schools and engage with guardians could encourage middle-aged adults to participate in regional sports activities. However, few CSLs work with guardians, and there is no evidence regarding what CSL characteristics encourage collaboration. The present study aimed to ascertain the aspects of coordination for CSLs collaborating with guardians in urban areas. Methods: A self-administered questionnaire survey was mailed to all 1,489 CSLs through 59 municipalities using the CSL out of 62 in Tokyo, Japan, from July to November 2021. The questionnaire covered sociodemographic data, variables related to CSL activities, coordination functions, and experience collaborating with guardians. We conducted a binomial logistic regression analysis using experience collaborating with guardians as the dependent variable, coordination function as the explanatory variable, and gender, age, residence duration, years of CSL experience, and the number of activities as covariates. Results: The analyzed sample comprised 478 CSLs. Binomial logistic regression analysis revealed a significant relationship between experience collaborating with guardians and the coordination function of internal/external CSL organizations, such as participation in non-CSL community activities, experience teaching and supporting their own children's sports, activity initiatives, number of times they used the school gymnasium, awareness of the regional sports plan, and cooperation with the chairman of the neighborhood association. Conclusions: Collaboration with guardians was related to CSL's individual experience engaging in regional sports from parenting and community collaboration, such as participation in non-CSL community activities and their relationship with the chairman of the neighborhood association. CSL activities may have the potential to encourage middle-aged adults to participate in regional sports.