Self-perceptions of aging, physical activity, and depressive symptoms in older community residents with varied neighborhood walkability in Taiwan.

BACKGROUND: Prior research has identified the mediating effect of physical activity in the relationship between self-perceptions of aging and physical health. However, this impact on mental health is unknown, and the influence of environmental contexts proposed by ecological models in this regard remains largely unexplored. Therefore, this study aimed to investigate the role of physical activity in the relationship between self-perceptions of aging and depressive symptoms in older adults, and compare the impact across four levels of neighborhood walkability. METHODS: A sample of 1,055 community-dwelling older adults aged 65 or above was obtained through random-digit-dialing computer-assisted telephone interviewing. The individual's neighborhood walkability was calculated using Walk Score®, and categorized into four levels: car-dependent, somewhat walkable, very walkable, and walker's paradise. Partial least squares structural equation modelling was employed. RESULTS: We found that more positive self-perceptions of aging were associated with fewer depressive symptoms and a mediation effect of physical activity in this relationship. Among the four levels of neighborhood walkability, the mediation effect of physical activity was only statistically significant in the lowest level (car-dependent). The findings supported our hypotheses regarding the mediating effect of self-perceptions of aging on depressive symptoms via physical activity. Neighborhood walkability might potentially influence the mediating role of physical activity. CONCLUSIONS: This study emphasizes key areas on intervention programs and policy formulation to promote mental health in older adults.

Association of 24-Hour movement behavior and cognitive function in older Taiwanese adults.

OBJECTIVES: This study investigates how 24-hour movement behaviors (physical activity, sedentary time, sleep) relate to cognitive performance in older adults. METHODS: 213 adults (aged 65+) wore accelerometers to track activity. Cognitive function was assessed using the Mini-Mental State Examination (MMSE). Isotemporal substitution analysis examined how replacing one behavior with another affected cognition. RESULTS: Increased light physical activity was linked to better cognitive function, whereas longer sleep had a negative impact. Replacing 30 min of sedentary behavior or sleep with light physical activity improved orientation, attention, language, and short-term memory. Substituting moderate-to-vigorous physical activity did not have the same cognitive benefit. CONCLUSION: Encouraging older adults to replace sedentary time or excess sleep with light physical activity could support cognitive health and potentially help prevent dementia. These findings have implications for public health strategies promoting cognitive well-being in aging populations.

Effect of information and communication technology-based smart care services for physical and cognitive functions in older adults living alone: A quasi-experimental study.

BACKGROUND: As the global population ages and the number of older adults living alone increases, societies face the responsibility of building new support systems and providing novel forms of care to ensure the independence and happiness of sick or frail older individuals. This quasi-experimental study examined the association between information and communication technology-based smart care services and the physical and cognitive functions of older individuals living alone. METHODS: This study used a suite of smart technologies (artificial intelligence speaker, radar sensor, and personalized exercise App.) and interventions tailored to the initial physical functional scores of the participants. A total of 176 participants were recruited and assigned, with 88 participants in the intervention group and 88 in the control group. The short physical performance battery (SPPB), the digit span test (DST), and the Korean mini-mental state examination (K-MMSE) were used to assess participants before and after 12 weeks. RESULTS: No significant differences in gender, age, or educational levels were observed between the intervention and control groups. After adjusting for baseline performance, analysis of covariance revealed that the intervention group exhibited better outcomes in the SPPB five-time chair stand score (adjusted score difference: 0.329; P = 0.044) and the backward DST (adjusted score difference: 0.472; P = 0.007), but had lower score of K-MMSE (adjusted score difference: -0.935; P = 0.021), indicating enhanced lower limb muscle strength and cognitive function in working memory. CONCLUSION: ICT-based smart care services, combined with personalized exercise interventions, significantly support the physical and cognitive health of solitary older individuals. This approach highlights the potential of integrating smart technology and targeted physical activity to foster the well-being of the aging population living alone.

Site-specific thrombus formation: advancements in photothrombosis-on-a-chip technology.

Thrombosis, characterized by blood clot formation within vessels, poses a significant medical challenge. Despite extensive research, the development of effective thrombosis therapies is hindered by substantial costs, lengthy development times, and high failure rates in medication commercialization. Conventional pre-clinical models often oversimplify cardiovascular disease, leading to a disparity between experimental results and human physiological responses. In response, we have engineered a photothrombosis-on-a-chip system. This microfluidic model integrates human endothelium, human whole blood, and blood flow dynamics and employs the photothrombotic method. It enables precise, site-specific thrombus induction through controlled laser irradiation, effectively mimicking both normal and thrombotic physiological conditions on a single chip. Additionally, the system allows for the fine-tuning of thrombus occlusion levels via laser parameter adjustments, offering a flexible thrombus model with varying degrees of obstruction. Additionally, the formation and progression of thrombosis noted on the chip closely resemble the thrombotic conditions observed in mice in previous studies. In the experiments, we perfused recalcified whole blood with Rose Bengal into an endothelialized microchannel and initiated photothrombosis using green laser irradiation. Various imaging methods verified the model's ability to precisely control thrombus formation and occlusion levels. The effectiveness of clinical drugs, including heparin and rt-PA, was assessed, confirming the chip's potential in drug screening applications. In summary, the photothrombosis-on-a-chip system significantly advances human thrombosis modeling. Its precise control over thrombus formation, flexibility in the thrombus severity levels, and capability to simulate dual physiological states on a single platform make it an invaluable tool for targeted drug testing, furthering the development of organ-on-a-chip drug screening techniques.

Cross-sectional association of physical activity levels with risks of sarcopenia among older Taiwanese adults.

OBJECTIVES: The updated World Health Organization 2020 guidelines strongly recommend an optimal physical activity level of 150-300 min/week for older adults. However, few studies have examined the relationship between different levels of physical activity and sarcopenia. Therefore, the purpose of this study was to investigate the cross-sectional associations between overall physical activity levels, gender, intensity, and the risk of sarcopenia among older Taiwanese adults. METHODS: A nationwide cross-sectional telephone survey of older adults (≥ 65 years) was conducted in Taiwan from October 2019 to January 2020. Participants were interviewed to collect self-reported data on their level of physical activity (measured by the Taiwanese version of the IPAQ-SF), sarcopenia risk (measured by the SARC-F questionnaire), and sociodemographics. RESULTS: A total of 1068 older adults were surveyed. Compared with the optimal physical activity level recommendations in the WHO guidelines and after adjusting for potential confounders and proposing an association independent of sedentary behavior, older adults with insufficient physical activity levels (< 150 min/week) were more likely to have a higher risk of sarcopenia (OR: 3.24; CI: 1.67-6.27), whereas older adults who exceeded physical activity guidelines (> 300 min/week) were more likely to have a lower risk of sarcopenia (OR: 0.39; CI: 0.20-0.78). Maintaining moderate-intensity physical activity is essential for older adults, as physical activity that exceeds the guidelines can significantly lower the risk of sarcopenia; meanwhile, insufficient physical activity can greatly increase it. Also, there seems to be a similar association between sarcopenia risk across different physical activity levels in vigorous-intensity physical activities in older adults. However, due to the small number of sarcopenia-risk participants who met or exceeded vigorous-intensity physical activity levels, further comparisons between different vigorous-intensity physical activity levels did not show significant differences in sarcopenia risk. Additionally, insufficient physical activity was found to be an important risk factor for sarcopenia in both genders, while physical activity that exceeded the guidelines prevented sarcopenia in females. CONCLUSIONS: The findings of this study highlight the potential dose-response relationship related to physical activity. The 2020 WHO guidelines provide the public with minimum recommendations for physical activity. However, exceeding these recommended levels appears to be more effective in preventing sarcopenia in older adults and may offer even greater health benefits. Future research should further explore whether exceeding these guidelines could result in additional health benefits.

Can weekend catch-up sleep decrease the risk of cognitive dysfunction in older adults?

PURPOSE: This study investigated whether weekend catch-up sleep was related to a decreased risk of cognitive dysfunction in older Taiwanese adults by using self-reported diaries and objective accelerometer measurements. METHODS: This cross-sectional study enrolled participants who were aged ≥ 65 years and had the capability to walk independently from a medical center in Taipei City, Taiwan, between September 2020 and December 2022. Self-reported sleep diaries and tri-axial accelerometers were used to record and measure sleep-related data for 7 consecutive nights. Weekend catch-up sleep was defined as the mean of weekend sleep time minus the mean of weekdays sleep time. Mini-Mental State Examination (MMSE) was evaluated the risk of cognitive dysfunction. The association between weekend catch-up sleep and the MMSE score was examined using a binary logistic regression model. RESULTS: A total of 215 older adults (53.0% female; 80.5 ± 7.1 years old; 11.6% at risk of cognitive dysfunction) were included. In the adjusted model (adjusted for sex, education level, moderate-to-vigorous physical activity and total accelerometer wear time), both the self-reported sleep diaries (odds ratio [OR] = 0.26, 95% confidence interval [CI] = 0.09-0.69, P = 0.007) and the accelerometer data (OR = 0.27, 95% CI = 0.10-0.70, P = 0.007) indicated that weekend catch-up sleep could decrease the risk of cognitive dysfunction by 73-74%. CONCLUSION: The study findings suggest that there is an association between weekend catch-up sleep and lower risk for cognitive decline. The causal relationship between weekend catch-up sleep and cognitive function in older adults should be further investigated in a study with longitudinal design.

Associations between objectively measured overall and intensity-specific physical activity and phase angle in older adults.

Phase angle (PhA) is an indicator of cellular health and is positively associated with overall physical activity (PA). However, varied associations between different intensities of PA and PhA by body segment in older populations remain unexplored. We investigated the associations between overall and different intensities of PA and upper-, lower-, and whole-body PhA in older adults. Overall exposure to light-intensity (LPA), moderate-intensity (MPA), and vigorous-intensity physical activity (VPA) was assessed using a triaxial accelerometer (GT3X + , ActiGraph). The outcome variables were upper-, lower-, and whole-body PhA measured using bioelectrical impedance analysis (MC-780MA, TANITA). Multiple linear regression helped examine the associations between the exposure and outcome variables after adjusting for age, gender, body mass index, and accelerometer wear time. A cross-sectional analysis involved 166 community-dwelling older participants (mean age = 72.1 ± 5.5 years; 78.3% women). Overall PA was associated with larger upper- (B: 0.057, 95% confidence interval [CI] 0.018-0.095) and whole-body PhA (B: 0.044, 95% CI 0.006-0.081). LPA was associated with larger upper-body PhA (B: 0.059, 95% CI 0.017-0.101), and MPA was associated with larger lower- (B: 0.273, 95% CI 0.128-0.419) and whole-body PhA (B: 0.141, 95% CI 0.002-0.280). VPA and PhA were not associated. Future interventions targeting PhA in older adults should consider the differential impact of PA intensity on various body segments of the PhA.

Capillary action-driven surface-enhanced Raman spectroscopy (SERS) for the identification of phthalocyanine blue in modern paintings based on the BPG spot test.

A method for the extraction and accumulation of Ag nanoparticles utilizing capillary action through a piece of triangular-shaped cotton paper is reported. This method allowed the integration of SERS and the BPG spot test, which are typically employed for examining pigments on paper or in books. Malachite green oxalate was used as the model material for investigating the extent of enhancement when SERS was applied. The dynamic behavior of the Ag nanoparticles was also studied. When the cotton paper was pre-treated with malachite green oxalate, Ag nanoparticles could be extracted and accumulated on the triangular top, resulting in a dramatic SERS improvement. When malachite green oxalate (at a concentration of 10-6 M) was applied using this method, a dramatic analytical enhancement factor of approximately 3000% was obtained. Finally, the method developed in this study was successfully applied to the analysis of pigments in paintings from a university collection. The findings revealed that phthalocyanine blue was a popular pigment used in numerous paintings during the 1950s.

Household physical activity and subjective well-being: An international comparison among East Asian older adult populations.

PURPOSE: Engaging in lifelong physical activity has multiple health benefits for older populations. Household physical activity occupies older adults' awake time, and they can be an important energy expenditure during the day. The purpose of this study was to investigate the association between older adults' household physical activity and subjective well-being in four East Asian societies. METHODS: The study design was a secondary data analysis. Data were retrieved from the module of Families 2016 in the database of the East Asian Social Survey. Participants were community-dwelling older adults with a mean age of 70.30±7.50 years and who lived in China, Japan, Korea, and Taiwan. Data were collected by interviews via structured questionnaires between 2016 and 2018. Descriptive analyses, independent t-tests, and an analysis of covariance were performed for the statistical analyses. RESULTS: In total, there were 3,432 valid responses. Participants who lived in Taiwan had significantly lower levels of total household physical activity than those living in other societies. Older adults' household physical activity was found to significantly differ by age, educational degree, gender, religion, marital status, occupation, and whether living alone. Older adults with high levels of household physical activity had significantly higher self-rated health and marital satisfaction than those with low levels. CONCLUSIONS: Household physical activity has potential benefits for subjective well-being across international older adult populations. Increasing household physical activity is recommended for older married couples to maintain marital satisfaction.

Is overall and timing-specific physical activity associated with depression in older adults?

Objective: Regarding the circadian rhythm regulating an individual's response to external stimulation, it remains unclear whether older adults engaged in physical activity at different times of day may be differently related to depression symptoms. Thus, this study aimed to investigate the association between overall and timing-specific physical activity and depressive symptoms in older Taiwanese adults. Methods: This cross-sectional study was conducted at a medical center in Taipei City, Taiwan, between September 2020 and December 2021. The participants were community-dwelling older adults aged ≥65 who could walk independently and were not at high risk of cognitive dysfunction. Physical activity was measured using a triaxial accelerometer (GT3X+, ActiGraph) and categorized into timing-specific periods (morning: 06:01-12:00; afternoon: 12:01-18:00; evening: 18:01-24:00) as well as overall physical activity, which included both light physical activity (LPA) and moderate-to-vigorous physical activity (MVPA). A 15-item Geriatric Depression Scale was utilized to assess and measure depressive symptoms. Multivariate linear regression models were estimated for data analysis. Results: A total of 180 older adults (55.0% female; 80.5 ± 7.1 years old; 18.3% at risk of depression) were included. On average, the participants spent 237.3 (± 85.7) minutes in LPA per day and 12.8 (± 17.0) minutes in MVPA per day. The results showed that overall MVPA engagement was associated with lower depressive-symptom scores [B = -1.357, 95% CI (-2.561, -0.153)] in older adults. However, no significant associations were observed between overall LPA, timing-specific MVPA and LPA, and depression in older adults. Conclusion: To prevent depression in older adults, it is advisable to accumulate a higher amount of MVPA throughout the entire day rather than engage in LPA. Further studies employing a prospective design are necessary to validate and strengthen our findings.

Objective assessment of the association between frailty and sedentary behavior in older adults: a cross-sectional study.

BACKGROUND: Given the inconsistent findings of the association between frailty and sedentary behavior in older adults, this cross-sectional study investigated the aforementioned association using four different frailty criteria and two sedentary behavior indices in older adults. METHODS: Data from older adults (age ≥ 65 y) who participated in health examinations or attended outpatient integrated clinics at a medical center in Taipei, Taiwan, were collected. Frailty was measured using the modified Fried Frailty Phenotype (mFFP), Clinical Frailty Scale in Chinese Translation (CFS-C), Study of Osteoporotic Fractures (SOF) index, and Clinical Frailty-Deficit Count (CF-DC) index; sedentary behavior was assessed with a waist-worn accelerometer. Adjusted linear regression ascertained the association between frailty and both sedentary behavior outcomes. RESULTS: Among the 214 participants (mean age 80.82 ± 7.14 y), 116 were women. The average total sedentary time and number of sedentary bouts were 609.74 ± 79.29 min and 5.51 ± 2.09 times per day, respectively. Frail participants had a longer total sedentary time (odds ratio [OR]: 30.13, P = .01 and 39.43, P < .001) and more sedentary bouts (OR: 3.50 and 5.86, both P < .001) on mFFP and CFS-C assessments, respectively. The SOF index revealed more sedentary bouts among frail than in robust participants (OR: 2.06, P = .009), without a significant difference in the total sedentary time. Frail participants defined by the CF-DC index were more likely to have frequent sedentary bouts (OR: 2.03, P = .016), but did not have a longer total sedentary time. CONCLUSIONS: Regardless of the frailty criteria adopted, frailty was positively associated with the number of sedentary bouts per day in older adults. A significant correlation between frailty and total sedentary time was detected only with mFFP and CFS-C indices. Further research may target decreasing the sedentary bouts in older adults as a strategy to improve frailty.

Associations of accelerometer-measured sedentary behavior and physical activity with sleep in older adults.

BACKGROUND: Few studies have examined the non-linear relationships of objectively-measured sedentary behavior and physical activity with insomnia symptoms in older adults. We investigated such relationships of sedentary and physically-active behaviors with total sleep time and nocturnal wakefulness. METHODS: We recruited adults aged 60 years and above who have received health check-ups or been to geriatric outpatient services from a hospital setting. Sedentary and physically-active behaviors, total sleep time, and wakefulness time after sleep onset were measured by Actigraphy, and their relationships were estimated using generalized additive models. RESULTS: The 157 older adults receiving health-related services slept 7.5 h (20.8 min awake) on average per day. Total sleep time was negatively associated with sedentary and physically-active behaviors. By contrast, a U-shape relationship was found between sedentary behavior and wakefulness time after sleep onset, with a turning point at a daily sedentary time of 10.9 h. CONCLUSION: Longer high-intensity physical activity time was related to a shorter wakefulness time after sleep onset. By contrast, daily sedentary time longer than 10.9 h was related to shorter total sleep time but more nocturnal wakefulness time. Future nonpharmacological strategies for sleep improvement should consider the sedentary threshold.

The Association between a Minimum Amount of Physical Activity and Subsequent Muscle Strength and Balance in Older Adults: A Prospective Study.

This study aimed to investigate the association between 15 min of daily moderate-to-vigorous physical activity (MVPA) and subsequent muscle strength and balance in older adults. Data concerning community-dwelling older Taiwanese adults (mean age, 69.5 years) were collected during the baseline period (2018) and at a 12-month follow-up survey (2019). Time spent performing MVPA was objectively assessed using a triaxial accelerometer (ActiGraph wGT3x-BT) at baseline. Upper and lower limb muscle strength were measured using handgrip strength and a five-times sit-to-stand test, respectively. Balance was assessed using a one-leg standing test. The 12-month variations in muscle strength and balance were calculated through subtracting follow-up data from baseline data. A forced entry-adjusted logistic regression analysis was conducted. In total, 65.2% of participants engaged in at least 15 min of daily MVPA in the baseline survey. After adjusting for confounders, older adults who achieved 15 min of daily MVPA during the baseline period were more likely to maintain or improve balance performance (odds ratio, 8.12). Performing 15 min of daily MVPA was found to benefit older adults' subsequent balance performance but not muscle strength.

Effect of isotemporal substitution of sedentary behavior with different intensities of physical activity on the muscle function of older adults in the context of a medical center.

BACKGROUND: Engaging in physical activity and reducing sedentary time in daily life may enable older individuals to maintain muscle mass. This study aimed to investigate the effects of replacing sedentary behavior with light physical activity (LPA) or moderate-to-vigorous physical activity (MVPA) on the muscle function of older adults at a medical center in Taiwan. METHODS: We recruited 141 older adults (51.1% men; 81.1 ± 6.9 years old) and asked them to wear a triaxial accelerometer on the waist to measure their sedentary behavior and physical activity. Functional performance was assessed based on handgrip strength, Timed Up and Go (TUG) test, gait speed, and five-times-sit-to-stand test (5XSST). Isotemporal substitution analysis was performed to examine the effect of substituting 60 min of sedentary time with 60 min of LPA, MVPA, and combined LPA and MVPA in different proportions. RESULTS: Reallocating 60 min of sedentary behavior per day to LPA was associated with better handgrip strength (Beta [B] = 1.587, 95% confidence interval [CI] = 0.706, 2.468), TUG test findings (B = -1.415, 95% CI = -2.186, -0.643), and gait speed (B = 0.042, 95% CI = 0.007, 0.078). Reallocating 60 min of sedentary behavior per day to MVPA was associated with better gait speed (B = 0.105, 95% CI = 0.018, 0.193) and 5XSST findings (B = -0.060, 95% CI = -0.117, -0.003). In addition, each 5-min increment in MVPA in the total physical activity replacing 60 min of sedentary behavior per day resulted in greater gait speed. Replacing 60 min of sedentary behavior with 30-min of LPA and 30-min of MVPA per day significantly decreased the 5XSST test time. CONCLUSION: Our study indicates that introducing LPA and a combination of LPA and MVPA to specifically replace sedentary behavior may help maintain muscle function in older adults.

Diurnal pattern of breaks in sedentary time and the physical function of older adults.

BACKGROUND: The association of breaks in sedentary time with outcomes of physical function can vary according to the time of day. We examined the association of the diurnal pattern of breaks in sedentary time with physical function outcomes in older adults. METHODS: A cross-sectional analysis was conducted among 115 older adults (≥60 years). The overall and time-specific breaks (morning: 06:00-12:00; afternoon: 12:00-18:00; evening: 18:00-24:00) in sedentary time were assessed using a triaxial accelerometer (Actigraph GT3X+). A break in sedentary time was defined as at least 1 min where the accelerometer registered ≥100 cpm following a sedentary period. Five physical function outcomes were assessed: handgrip strength (dynamometer), balance ability (single leg stance), gait speed (11-m walking), basic functional mobility (time up and go), and lower-limb strength (five times sit-to-stand). Generalized linear models were used to examine the associations of the overall and time-specific breaks in sedentary time with the physical function outcomes. RESULTS: Participants showed an average of 69.4 breaks in sedentary time during the day. Less frequent breaks in the evening (19.3) were found than that in the morning (24.3) and the afternoon (25.3) (p < 0.05). Breaks in sedentary time during the day were associated with less time on gait speed in older adults (exp (ß) = 0.92, 95% confidence interval [CI] 0.86-0.98; p < 0.01). Time-specific analysis showed that breaks in sedentary time were associated with less time on gait speed (exp (ß) = 0.94, 95% CI 0.91-0.97; p < 0.01), basic functional mobility (exp (ß) = 0.93, 95% CI 0.89-0.97; p < 0.01), and lower-limb strength (exp (ß) = 0.92, 95% CI 0.87-0.97; p < 0.01) in the evening only. CONCLUSION: A break in sedentary time, particularly during the evening, was associated with better lower extremity strength in older adults. Further strategies to interrupt sedentary time with frequent breaks, with an emphasis on evening hours, can be helpful to maintain and improve physical function in older adults.

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.

Domain-specific Physical Activity and the Risk of All-cause Mortality Among Middle-aged and Older Adults in Taiwan: A Prospective Cohort Study.

BACKGROUND: The impact of meeting leisure-time physical activity (LTPA) recommendations and household physical activity (HPA) on all-cause mortality in the Taiwanese population is unclear. We aimed to investigate the relationship between sufficient LTPA and all-cause mortality in middle-aged and older Taiwanese adults and the role of HPA in those with insufficient LTPA. METHODS: This nationwide prospective cohort study included 4,960 participants aged ≥50 years from the Taiwan Longitudinal Study in Aging (TLSA) survey. Physical activity patterns were assessed in 2003 and then followed up until 2015 for mortality through the National Death Registration Record. Cox proportional hazards regression was conducted to evaluate hazard ratios (HRs) and 95% confidence intervals (CIs) for all-cause mortality. RESULTS: Of the 4,960 participants, 1,712 died of all-cause mortality. Compared to those who had insufficient LTPA, participants who engaged in sufficient LTPA showed a significantly lower risk of all-cause mortality (HR = 0.84, 95% CI, 0.73-0.97). For those with insufficient LTPA, HPA also had a significantly reduced risk of all-cause mortality (HR = 0.85, 95% CI, 0.75-0.96) among general population. Similar associations were observed in subsequent sensitivity analyses. The subgroup analysis showed that the relationship between HPA and reduced mortality risk was only found in the women with insufficient LTPA group. CONCLUSION: This study confirmed that sufficient LTPA is associated with a lower risk of all-cause mortality. If sufficient LTPA cannot be performed, additional HPA is related to lower mortality.

Relationship of sleep regularity with device-based sedentary behavior time and physical activity time in working adults.

OBJECTIVES: This study aimed to investigate the association of sleep regularity with time spent in sedentary behavior (SB) and physical activity (PA) in adults with full-time jobs. METHODS: This was a cross-sectional study. Adults aged 21-64 years with full-time jobs were recruited between August 2019 and December 2020 in Taiwan. The time spent in SB/PA was assessed using triaxial accelerometers (Actigraph wGT3x-BT), and PA was further classified into light-intensity physical activity (LPA) and moderate-to-vigorous intensity physical activity (MVPA). Each participant recorded their daily sleep patterns and work hours in a log, which was further used to measure sleep variability and social jet lag. Linear regression was applied to examine the associations of indicators of sleep regularity with SB time and PA time. RESULTS: A total of 192 adults (men = 28.13%; mean age = 38.56 ± 8.89 years) were included in this study. After adjusting for potential covariates, greater social jet lag was related to more SB time (unstandardized coefficient [B] = 14.39, P = .005) and less LPA time (B = -0.02, P = .010). No evidence of an association between other indicators of sleep regularity with SB/PA time was found. CONCLUSIONS: These results provide evidence for a relationship between sleep regularity and SB/PA time in working adults. Maintaining regular sleep, especially a small social jet lag, was suggested to promote physical activity and avoid a sedentary lifestyle. Future research is recommended to examine work-related influences on the associations and bidirectional relationship between sleep regularity and SB/PA.

Associations of the audited residential neighborhood built-environment attributes with objectively-measured sedentary time among adults: a systematic review.

This study systematically reviewed the relevant studies and summarized the associations of objective measures of residential neighborhood built-environment attributes with sedentary time among adults. Published studies were obtained from PubMed and Scopus, restricting to those published in English language peer-reviewed journals to Oct. 2021. There were nine studies and 48 instances of estimated associations. Most instances showed no statistical-significant associations; by contrast, few instances showed that adults living in a neighborhood characterized by a high density of local destinations and connected intersections were associated with less sedentary time. The findings suggest that a high density of destinations and street intersections around residence may provide opportunities to transfer and access to services, thus reducing the sedentary time. Future research strengthening the research design and measurements are needed to investigate the potential explanations of the associations between residential neighborhood built environments and sedentary time in adults.