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.

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.

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.

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.

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.

A dose response relationship between accelerometer assessed daily steps and depressive symptoms in older adults: a two-year cohort study.

OBJECTIVES: this study investigated the prospective associations of accelerometer assessed daily steps with subsequent depressive symptoms in older adults. METHODS: a 2-year prospective study was performed in the community. A total of 285 older adults ≥65 years (mean age = 74.5) attended the baseline assessment in 2012. The second wave of assessment was carried out in 2014 including 274 (96.1%) participants. Daily step counts were measured with a triaxial accelerometer (ActiGraph GT3X+), and participants were divided into three categories (<3,500, 3,500-6,999 and ≥ 7,000 steps/day). The 15-item Geriatric Depression Scale was used to measure depressive symptoms. Negative binomial regression models with multivariable adjustment for covariates (baseline depressive symptoms, accelerometer wear time, age, gender, education, chronic disease, activities of daily living) were conducted to examine the association between daily steps and subsequent depressive symptoms. RESULTS: each 1,000-step increase in daily walking was linearly associated with a reduced rate of subsequent depressive symptoms (rate ratio [RR] = 0.95, 95% confidence interval [CI] = 0.92-0.98). Participants with daily step count in 3,500-6,999 (RR = 0.84, 95% CI = 0.70-0.99) and ≥7,000 steps (RR = 0.71, 95% CI = 0.55-0.92) per day had fewer depressive symptoms at follow-up. Sensitivity analyses assessing confounding and reverse causation provided further support for the stability of our findings. CONCLUSION: older adults engaging in more daily steps had fewer depressive symptoms after 2 years. Even as few as 3,500-6,999 steps a day was associated with a protecting effect. Accumulating ≥7,000 steps a day could provide the greatest protection against depressive symptoms.

Is achieving 7,000 steps/day cross-sectionally and prospectively associated with older adults' lower-extremity performance?

BACKGROUND: Evidence regarding the association between daily steps recommendation and older adults' lower limb strength is lacking; thus, this study investigated whether taking at least 7,000 steps/day is cross-sectionally and prospectively related to lower-extremity performance in older Taiwanese adults. METHODS: There were 89 community-dwelling adults aged over 60 years (mean age: 69.5 years) attending both baseline and follow-up surveys. This study used adjusted logistic regression analysis to explore cross-sectional and prospective relationships between their accelerometer-assessed daily steps and lower-extremity performance (five-times-sit-to-stand test). RESULTS: This study found the older adults who took 7,000 steps/day were more likely to have better lower-extremity performance cross-sectionally (odds ratio [OR] = 3.82; 95 % confidence interval [CI]: 1.04, 13.95; p = 0.04), as well as to maintain or increase their lower-extremity performance prospectively (OR = 3.53; 95 % CI: 1.05, 11.84; p = 0.04). CONCLUSIONS: Our findings support a minimum recommended level of step-based physical activity for older adults, namely, 7,000 steps/day, as beneficial for maintaining or increasing older adults' lower-extremity performance.

Device-measured light-intensity physical activity and mortality: A meta-analysis.

INTRODUCTION: The association of light-intensity physical activity (LPA) with mortality is poorly understood. This meta-analysis of cohort studies aimed to examine the dose-response relationships between daily device-measured LPA and mortality in adults aged 18 or older and to explore whether the associations were independent of moderate-to-vigorous physical activity (MVPA). METHODS: Searches for prospective cohort studies providing effect estimates of daily LPA (exposure) on all-cause mortality (outcome) were systematically undertaken in electronic databases up to April 30, 2019. Subgroup analyses and meta-regression analyses with random-effects models were performed to quantify the dose-response relationships between daily LPA and mortality. Sensitivity analyses were also conducted to assess the stability of the results. RESULTS: A total of 11 studies were included in the meta-analysis. Analyses contained 49 239 individuals (mean age 60.7, SD = 13.6) who were followed up for a mean 6.2 years (2.3-14.2 years), during which 3669 (7.5%) died. In comparison with the reference group (<3 h/d), the pooled HRs (and 95% CIs) of mortality were 0.71 (0.62-0.82), 0.68 (0.59-0.79), 0.56 (0.44-0.71) for groups 3 to <5 h/d, 5 to <7 h/d, and more than 7 hours a day LPA, respectively. Meta-regression models indicated that there was a log-cubic dose-response relationship between daily LPA and mortality in adults and older people, independent of MVPA. CONCLUSIONS: Time spent in daily LPA was associated with reduced risks of mortality in adults and older people. These data support the inclusion of LPA in the future physical activity guidelines.

Effects of Acute Aerobic Exercise on Executive Function in Children With and Without Learning Disability: A Randomized Controlled Trial.

This study examined the effects of acute aerobic exercise on sustained attention and discriminatory ability of children with and without learning disabilities (LD). Fifty-one children with LD and 49 typically developing children were randomly assigned to exercise or control groups. The participants in the exercise groups performed a 30-min session of moderate-intensity aerobic exercise, whereas the control groups watched a running/exercise-related video. Neuropsychological tasks, the Daueraufmerksamkeit sustained attention test, and the determination tests were assessed before and after each treatment. Exercise significantly benefited performance in sustained attention and discriminatory ability, particularly in higher accuracy rate and shorter reaction time. In addition, the LD exercise group demonstrated greater improvement than the typically developing exercise group. The findings suggest that the acute aerobic exercise influenced the sustained attention and the discriminatory function in children with LD by enhancing regulation of mental states and allocation of attentional resources.

A cut-off of daily sedentary time and all-cause mortality in adults: a meta-regression analysis involving more than 1 million participants.

BACKGROUND: The appropriate limit to the amount of daily sedentary time (ST) required to minimize mortality is uncertain. This meta-analysis aimed to quantify the dose-response association between daily ST and all-cause mortality and to explore the cut-off point above which health is impaired in adults aged 18-64 years old. We also examined whether there are differences between studies using self-report ST and those with device-based ST. METHODS: Prospective cohort studies providing effect estimates of daily ST (exposure) on all-cause mortality (outcome) were identified via MEDLINE, PubMed, Scopus, Web of Science, and Google Scholar databases until January 2018. Dose-response relationships between daily ST and all-cause mortality were examined using random-effects meta-regression models. RESULTS: Based on the pooled data for more than 1 million participants from 19 studies, the results showed a log-linear dose-response association between daily ST and all-cause mortality. Overall, more time spent in sedentary behaviors is associated with increased mortality risks. However, the method of measuring ST moderated the association between daily ST and mortality risk (p < 0.05). The cut-off of daily ST in studies with self-report ST was 7 h/day in comparison with 9 h/day for those with device-based ST. CONCLUSIONS: Higher amounts of daily ST are log-linearly associated with increased risk of all-cause mortality in adults. On the basis of a limited number of studies using device-based measures, the findings suggest that it may be appropriate to encourage adults to engage in less sedentary behaviors, with fewer than 9 h a day being relevant for all-cause mortality.

Personal and behavioral correlates of total and domain-specific sedentary behaviors in older Taiwanese adults.

BACKGROUND: Evidence of the harmful health effects of sedentary behavior is emerging; however, little is known about domain-specific sedentary behavior correlates. Thus, in this study, the personal and behavioral correlates of total and domain-specific sedentary behavior in older Taiwanese adults were identified. METHOD: The sample comprised 1046 older adults (aged ≥65 years). Cross-sectional data on self-administered personal behavioral variables and time spent engaging in domain-specific sedentary behavior were obtained using computer-assisted telephone-based interviews. Binary logistic regression analyses were performed. RESULTS: Those aged older than 75 years were less likely to have longer total sedentary, computer use, and transportation times. Compared to women, older men were more likely to have longer total sedentary and transportation times. Older adults with low educational levels were less likely to have longer total sedentary and computer use times but were more likely to have an excessive television (TV) viewing time (≥2 h/day). Older adults who lived alone and were overweight had a longer TV viewing time. Furthermore, unemployment was associated with an excessive TV viewing time and shorter transportation time. Older adults residing in nonmetropolitan areas had lower total sedentary, TV viewing, and computer use times. Older adults who engaged in insufficient leisure time physical activity were more likely to have longer total sedentary and transportation times. CONCLUSIONS: Both common and distinct personal and behavioral factors were associated with total and domain-specific sedentary behavior. Interventions for reducing total and domain-specific sedentary behavior should focus on both common and distinct subgroups of the Taiwanese older population.

Dog ownership, dog walking, and leisure-time walking among Taiwanese metropolitan and nonmetropolitan older adults.

BACKGROUND: This study examined the prevalence of dog ownership and dog walking and its association with leisure-time walking among metropolitan and nonmetropolitan older adults. METHODS: A telephone-based cross-sectional survey targeting Taiwanese older adults was conducted in November 2016. Data related to dog ownership, time spent dog walking (categorized as non-dog owner, non-dog walkers, and dog walkers), and sociodemographic variables were obtained from 1074 older adults. Adjusted binary logistic regression was then performed. RESULTS: In this sample, 12% of Taiwanese older adults owned a dog and 31% of them walked their dogs for an average of 232.13 min over 5.9 days/week (standard deviation = 2.03). Older adults living in nonmetropolitan areas were more likely to own a dog (14.7% vs. 9.1%) but less likely to walk their dog (25.9% vs. 39.6%) than were those living in metropolitan areas. Compared with non-dog owners, only older adults living in nonmetropolitan areas who were dog walkers achieved 150 min of leisure-time walking (odds ratio: 3.03, 95% confidence interval: 1.05-8.77), after adjustment for potential confounders. CONCLUSION: Older Taiwanese adults living in nonmetropolitan areas who owned and walked their dogs were more likely to achieve health-enhancing levels of leisure-time walking. Tailored physical activity interventions for promoting dog walking should be developed for older adults who are dog owners living in nonmetropolitan areas and who do not engage in dog walking.

Associations of Total and Domain-Specific Sedentary Time With Type 2 Diabetes in Taiwanese Older Adults.

BACKGROUND: The increasing prevalence of type 2 diabetes in older adults has become a public health concern. We investigated the associations of total and domain-specific sedentary time with risk of type 2 diabetes in older adults. METHODS: The sample comprised 1046 older people (aged ≥65 years). Analyses were performed using cross-sectional data collected via computer-assisted telephone-based interviews in 2014. Data on six self-reported domains of sedentary time (Measure of Older Adults' Sedentary Time), type 2 diabetes status, and sociodemographic variables were included in the study. Binary logistic regression analysis was performed to calculate the adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for total and individual sedentary behavior components and likelihood of type 2 diabetes. RESULTS: A total of 17.5% of the participants reported type 2 diabetes. No significant associations were found between total sitting time and risk of type 2 diabetes, after controlling for confounding factors. After total sedentary behavior was stratified into six domains, only watching television for more than 2 hours per day was associated with higher odds of type 2 diabetes (OR 1.56; 95% CI, 1.10-2.21), but no significant associations were found between other domains of sedentary behavior (computer use, reading, socializing, transport, and hobbies) and risk of type 2 diabetes. CONCLUSIONS: These findings suggest that, among domain-specific sedentary behavior, excessive television viewing might increase the risk of type 2 diabetes among older adults more than other forms of sedentary behavior.

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.

Effects of Coordinative Exercise on Sustained Attention and Perceptual Discrimination in Elementary School Physical Education.

Purpose: This study examined the effects of coordinative exercise on children's sustained attention and perceptual discrimination in a school-based physical education (SBPE) setting. Methods: Seventy-three children received an intervention of moderate-to-vigorous intensity coordinative exercise, and 75 children participated in a moderate-to-vigorous intensity physical activity as part of a regular physical education class. Two neuropsychological tests of executive function (EF) were used to assess attention and perceptual discrimination functions before and after each treatment. Results: The results found that coordinative exercise significantly improved the performances on sustained attention and perceptual discrimination, as evidenced by enhanced response accuracy and improved speed of responding. Specifically, higher progressions in task performance were seen following coordinative exercise relative to regular physical activity. Conclusion: These findings suggest that coordinative exercise could enable more robust improvements in sustained attention and perceptual discrimination among children. Overall, we conclude that structured coordinative exercise, implemented in SBPE settings, may be a promising alternative to promote children's cognitive abilities.

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.

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.

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.

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.