Associations of sedentary behavior and physical activity with older adults' physical function: an isotemporal substitution approach

Association of Moderate-to-Vigorous Physical Activity, Sedentary Time, Fat Percentage, and Physical Fitness with Gait Parameters in Women with Fibromyalgia: The Al-Ándalus Project

Gait impairments have been found in women with fibromyalgia, reducing the physical activity possibilities in this population and leading to a negative correlation with fibromyalgia impact. The aim of this study was to analyze the individual and independent associations of moderate-to-vigorous physical activity (MVPA), sedentary time, fat percentage, and physical fitness with gait parameters in women with fibromyalgia. A total of 84 women with fibromyalgia were included. MVPA and sedentary time were assessed with accelerometry, fat percentage with bioimpedance analysis, and physical fitness with field-based fitness tests. Gait was assessed during a "6 min walk test" and categorized in velocity, cadence, step length, step cycle duration, unipedal stance phase, and bipedal stance phase. Individual relationships were analyzed by partial correlations and independent relationships by linear regressions, adjusting by age and height. MVPA, sedentary time, fat percentage, and physical fitness were correlated with most gait parameters (rpartial between |0.842| and |0.219|; p ≤ 0.05). Physical fitness was independently associated with all gait parameters (β between |0.346| and |0.761|; p ≤ 0.002). In addition, MVPA was independently associated with velocity and step length (β = 0.241 and 0.292; both p = 0.004), and fat percentage was associated with bipedal stance phase (β = 0.242; p = 0.049). Good levels of MVPA, physical fitness, and adequate weight balance are associated with improved gait parameters in women with fibromyalgia.

Isotemporal substitution analysis of time between sleep, sedentary behavior, and physical activity on depressive symptoms in older adults: a cross-sectional study

BACKGROUND

Compared to young individuals, older adults participate more in sedentary behavior (SB) and less in physical activity (PA). These behaviors are associated with numerous adverse health factors.

OBJECTIVE

The purpose of the study was to examine the hypothetical effects of substituting time spent sleeping, performing SB, and performing moderate-to-vigorous physical activity (MVPA) on depressive symptomatology in older adults.

DESIGN AND SETTING

An analytical cross-sectional study employing exploratory survey methods was conducted in the city of Alcobaça in the state of Bahia, Brazil.

METHODS

The study included 473 older adults who answered a structured questionnaire during an interview. Exposure time to SB and PA level were assessed using the International Physical Activity Questionnaire, and depressive symptoms were analyzed using the short version of the Geriatric Depression Scale. An isotemporal replacement model was used to evaluate the effects of different SB sessions on depressive symptomatology.

RESULTS

An increase in the risk of depressive symptoms was observed when MVPA and sleep time were substituted for the same SB time at all times tested, with maximum values of 40% and 20%, respectively. Opposite substitution of MVPA and sleep time increments reduced the risk of depressive symptomatology by 28% and 17%, respectively.

CONCLUSIONS

The results of the present study indicate that replacing SB with the same amount of sleep or MVPA may reduce depressive symptoms. The longer the reallocation time, the greater are the benefits.

Trends in obesity, leisure-time physical activity, and sedentary behavior in Korean adults: Korea national health and nutritional examinations survey from 2014 to 2021

OBJECTIVES

This study aimed to investigate trends in obesity by dividing it based on body mass index (BMI) and waist circumference indicators, sedentary behavior, and leisure-time physical activity (LTPA) in Korean adults from 2014 to 2021. This study also aimed to determine the adherence rate of people with obesity to physical activity.

METHODS

Data from the Korea National Health and Nutritional Examination Survey (KNHANES) from 2014 to 2021 were used. A total of 42,676 participants 19 years or older were included in the final analysis. Sociodemographic characteristics, anthropometric measurements, and physical activity levels were recorded. Physical activity levels were assessed using the Global Physical Activity Questionnaire, a self-reported questionnaire. Multivariable logistic regression analysis adjusted for covariates was used to investigate the prevalence of obesity and sitting time or adherence to meeting the physical activity guidelines for each survey year.

RESULTS

This study included 42,676 adults. The weighted prevalence of obesity in all ages significantly increased from 30.8% (29.1%-32.5%) in 2014 to 34.5% (32.9%-36.2%) in 2017 and 37.3% (35.5%-39.1%) in 2021 (p for trend < 0.004). The weighted adherence rate to LTPA ranged from 25.5% (95% confidence interval [CI], 23.7%-27.2%) in 2014 to 20.5% (95% CI, 18.7%-22.2%) in 2021(p for trend < 0.001). The weighted prevalence of sitting time for 8 h/day or more significantly increased from 46.7% (44.4%-49.0%) in 2014 to 56.2% (54.4%-58.0%) in 2017 and 63% (60.7%-65.3%) in 2021 (p for trend < 0.001). According to this study, the LTPA level among women with obesity was significantly low.

CONCLUSION

From 2014 to 2021, obesity and sedentary behavior significantly increased and adherence to LTPA decreased among Korean adults. Given these concerning trends, comprehensive interventions are needed at the national level to encourage healthy lifestyle behaviors.

The circadian activity rhythms for elderly inpatients with stroke or motor diseases in a rehabilitation facility and its relationship to physical activity level

Disturbances in the circadian activity rhythms (CARs) of inpatients in rehabilitation facilities delay the recovery of physical and mental functions. The purpose of this study is to elucidate the circadian activity rhythms of hospitalized patients in a rehabilitation facilitie using the synthetic periodic regression analysis, and investigate the relationship between their physical activity levels and CARs.An observational study was conducted. A group of thirty-four inpatients participated in the study by wearing wrist-type activity monitors to measure metabolic equivalents (METs). Using synthetic periodic regression analysis, the CARs were analyzed based on the amount of physical activity throughout the day, and the exercise intensity classification of their physical activity was assessed. In the CARs of the inpatients, the mean physical activity level was 1.23 ± 0.09 METs. The maximum amount was 1.36 ± 0.15 METs. The range was 0.30 ± 0.15 METs. The maximum phase time was 11:48 ± 2:31 h. The longer the duration of physical activity over 1.6 METs, the higher the mean, maximum and range of the CARs. Physical activities with a METs level of 1.6 or higher might have an impact on the mean, maximum, and range of circadian activity rhythms in hospitalized patients.

Supplementary Information

The online version contains supplementary material available at 10.1007/s41105-023-00488-8.

Associations between physical activity, physical fitness, and body composition in adults living in Germany: A cross-sectional study

BACKGROUND & AIMS

Body composition (BC) changes with age and is associated with morbidity and mortality. A physically active lifestyle influences BC and represents an important predictor of successful aging. To emphasize this, the World Health Organization established activity recommendations for all age groups. We describe BC during adulthood using a cross-sectional sample from a German community and investigate the associations between physical activity (PA), physical fitness (PF), and BC.

METHODS

Data from 329 men and women aged 35 to 86 years were analyzed. PA was measured by questionnaire and classified into sport activity and habitual activity. PF was measured through physical performance tests and BC by bioelectrical impedance analysis. Fat mass index (FMI) and fat-free mass index (FFMI) were calculated to represent height-adjusted BC. Associations between PA, PF, and BC were analyzed using linear regression models.

RESULTS

For both sexes, strength was positively associated with FFMI (♂: ß = 0.313; ♀: ß = 0.213) and phase angle (♂: ß = 0.357; ♀: ß = 0.409). For FMI, a significant negative association with strength was found only in women (ß = -0.189). Cardiorespiratory fitness showed a negative association with FMI (ß = -0.312) and FFMI (ß = -0.201) for men, while in women a positive association was found for FFMI (ß = 0.186). For coordination, a significant association with FMI was observed only in women (ß = -0.190). Regarding PA only one significant relationship between sport activity and FMI among women (ß = -0.170) was found.

CONCLUSIONS

In our sample, PF was closer related to BC than PA. Strength and cardiorespiratory fitness were the strongest predictors for BC. This supports the World Health Organization's activity recommendations to include both resistance and endurance training in the weekly sports program to maintain a healthy BC.

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.

Determinants of new participation in sports groups among community-dwelling older adults: Analysis of a prospective cohort from The Otassha Study

Participation in sports groups has health benefits for older adults, such as preventing functional limitations and social isolation. Encouraging participation in sports groups may be an important means of health promotion in older adults. However, there is insufficient research on the determinants of new participation in sports groups to consider effective interventions to promote participation in these groups. We investigated this using data from a 1-year prospective study. Data were obtained from "The Otassha Study" that assessed a cohort of community-dwelling older adults living in an urban area of Japan. Of 769 older adults who participated in a baseline health survey in 2018, 557 participated in a follow-up survey in 2019. We excluded 184 individuals who already participated in sports groups at baseline and 36 with missing data. Participation in sports groups was defined as that occurring more than once a week. Logistic regression analysis was used to identify the determinants of new participation in sports groups, with sociodemographic factors, lifestyle habits, physical functions, cognitive functions, psychological factors, and social factors as independent variables. Forty-one (12.2%) individuals participated in sports groups at follow-up. In the multiple adjusted logistic regression model, new participation in sports groups was significantly associated with female sex (odds ratio [OR] = 5.57, 95% confidence interval [CI]: 1.61‒19.26), engagement in regular exercise (OR = 2.23, 95%CI: 1.03‒4.84), and having a large social network (OR = 1.12, 95%CI: 1.04‒1.20). Physical functions were not associated with new participation. Determinants of new participation were lifestyle habits and social factors, rather than physical functions. Intervention through social networks may be effective in encouraging new participation in sports groups, which, in turn, may facilitate healthy aging.

Facilitators and barriers to real-life mobility in community-dwelling older adults: a narrative review of accelerometry- and global positioning system-based studies

Real-life mobility, also called "enacted" mobility, characterizes an individual's activity and participation in the community. Real-life mobility may be facilitated or hindered by a variety of factors, such as physical abilities, cognitive function, psychosocial aspects, and external environment characteristics. Advances in technology have allowed for objective quantification of real-life mobility using wearable sensors, specifically, accelerometry and global positioning systems (GPSs). In this review article, first, we summarize the common mobility measures extracted from accelerometry and GPS. Second, we summarize studies assessing the associations of facilitators and barriers influencing mobility of community-dwelling older adults with mobility measures from sensor technology. We found the most used accelerometry measures focus on the duration and intensity of activity in daily life. Gait quality measures, e.g., cadence, variability, and symmetry, are not usually included. GPS has been used to investigate mobility behavior, such as spatial and temporal measures of path traveled, location nodes traversed, and mode of transportation. Factors of note that facilitate/hinder community mobility were cognition and psychosocial influences. Fewer studies have included the influence of external environments, such as sidewalk quality, and socio-economic status in defining enacted mobility. Increasing our understanding of the facilitators and barriers to enacted mobility can inform wearable technology-enabled interventions targeted at delaying mobility-related disability and improving participation of older adults in the community.

Factors Associated with Handgrip Strength Among Older Adults in Malaysia

Purpose

Handgrip strength (HGS) is indicative of overall physical health among older adults. A decrease in HGS may be associated with an increased risk of disease. The aim of this study is to determine the factors associated with HGS among older adults in Malaysia.

Patients and Methods

One thousand two hundred four (1204) participants from urban and rural areas in Selangor state, Malaysia, were recruited. Sociodemographic and health-related conditions were gathered through a comprehensive face-to-face interview, followed by HGS assessments by a handgrip dynamometer. Subsequently, multiple linear regression was used to test the main association with the HGS.

Results

A total of 691 participants (57.4%) were male, and 513 (42.6%) were female. Males had a mean HGS of 30.0 (SD 7.53) kg, and females had a mean HGS of 19.4 (SD 5.28) kg. Males’ handgrip strength was significantly reduced with increasing age, physically inactive, and diabetes (all at the level p<0.001) after adjusting for social-demographic characteristics and health-related variables. Meanwhile, for females, the HGS was significantly decreased with age (p<0.001), physically inactive (p<0.001) and hypertension (p=0.03). However, female HGS was positively related to BMI (p<0.001).

Conclusion

The study contributed to a better understanding of factors associated with HGS, and thus, the HGS is recommended as a section in the health evaluation among high-risk older adults as the strategy of disease control and prevention.

Replacing Sedentary Behavior With Physical Activity of Different Intensities: Implications for Physical Function, Muscle Function, and Disability in Octogenarians Living in Long-Term Care Facilities

BACKGROUND

We investigated the associations of replacing sedentary behavior (SB) with physical activity of different intensities on the physical function of octogenarians living in long-term care facilities.

METHODS

This pooled study recruited 427 older adults aged 80 years and older (69.1% female; body mass index: 27.53). For 345 participants who provided valid data, we assessed device-measured time spent in SB, light-intensity physical activity (LIPA), and moderate to vigorous physical activity (MVPA). We assessed lower limb physical function, strength, mobility, and disability. We used compositional data analysis to investigate the associations of replacing SB with physical activity on the outcomes.

RESULTS

Reallocation of SB to LIPA and MVPA was associated with a higher number of 30-second Chair Stand cycles (LIPA: +0.21, MVPA: +1.81; P < .001), greater peak force (LIPA: +11.96 N, MVPA: +27.68 N; P < .001), peak power (LIPA: +35.82 W, MVPA: +92.73 W; P < .001), peak velocity (LIPA: +0.03 m/s, MVPA: +0.12 m/s; P < .001), higher levels of grip strength (LIPA: +0.68 kg, MVPA: +2.49 kg; P < .001), and less time in the Time Up and Go (LIPA: -7.63 s, MVPA: -12.43 s; P < .001).

CONCLUSIONS

Replacing SB with LIPA or MVPA is associated with physical function and disability of older adults living in long-term care facilities.

Assessment of Physical Activity and Related Factors among Adults with Visual Impairments in Japan

In Japan, there is a lack of physical activity data on health and disease among people with visual impairments, making it difficult to develop specific strategies for health promotion. This study aimed to identify moderate-to-vigorous physical activity (MVPA) among people with visual impairments in Japan, to examine the percentage of them who meet the MVPA recommended activity, and to identify factors related to MVPA. In this cross-sectional study, we analyzed a survey of 169 adults with visual impairments. The relationship between MVPA and related factors was analyzed using binomial logistic regression analysis. The median MVPA was 46 min/day for men and 36 min/day for women, respectively, aged < 65 years, and 26 min/day for men and 34 min/day for women, respectively, aged ≥ 65 years. Seventy-eight percent of the subjects achieved the recommendations by the WHO, and 28% of the subjects < 65 years had achieved the MVPA of 60 min/day recommended by the Japanese Active Guide. Self-efficacy (SE) for PA, recommended PA implementation behavior, subjective walking speed, and exercise habits were significantly associated with MVPA. The current status of MVPA time among people with visual impairments in Japan, as revealed by this study, indicates that it is important to set realistic goals and plan a step-by-step process to achieve the recommendation. In the future, it will be important to develop a program that encourages the improvement of SE and promotes PA.

Effects of Reallocating Time Spent in Different Physical Activity Intensities on Sarcopenia Risk in Older Adults: An Isotemporal Substitution Analysis

Simple Summary

The role of daily time spent sedentary and in different intensities of physical activity (PA) for maintenance of muscle health is currently unclear. Therefore, we investigated the impact of reallocating time spent in different PA intensities on a sarcopenia risk score (SRS) in older adults, while considering PA type (muscle strengthening activities, MSA) and protein intake. In the present study, we show for the first time that reallocating sedentary time with at least light-intensity PA was significantly related to a lower SRS, which remained evident after adjustment by PA type (MSA) and protein intake. Similarly, reallocating time in light- to moderate-to-vigorous-intensity PA was related to a significantly lower SRS. Our results emphasize the importance of displacing sedentary behaviours for more active pursuits, where PA of even light intensities may alleviate age-related deteriorations of muscle health in older adults.

Abstract

The role of daily time spent sedentary and in different intensities of physical activity (PA) for the maintenance of muscle health currently remains unclear. Therefore, we investigated the impact of reallocating time spent in different PA intensities on sarcopenia risk in older adults, while considering PA type (muscle strengthening activities, MSA) and protein intake. In a sample of 235 community-dwelling older adults (65–70 years), a sarcopenia risk score (SRS) was created based on muscle mass assessed by bioimpedance, together with handgrip strength and performance on the five times sit-to-stand (5-STS) test assessed by standardized procedures. Time spent in light-intensity PA (LPA), moderate-to-vigorous PA (MVPA), and being sedentary was assessed by accelerometry, and PA type (MSA) by self-report. Linear regression models based on isotemporal substitution were employed. Reallocating sedentary time to at least LPA was significantly (p < 0.05) related to a lower SRS, which remained evident after adjustment by PA type (MSA) and protein intake. Similarly, reallocating time in LPA by MVPA was related to a significantly (p < 0.05) lower SRS. Our results emphasize the importance of displacing sedentary behaviours for more active pursuits, where PA of even light intensities may alleviate age-related deteriorations of muscle health in older adults.

The Associations between Objectively Measured Physical Activity and Physical Function in Community-Dwelling Older Japanese Men and Women

Objective: The relationships between physical activity (PA) and physical function (PF) among older Japanese adults have been examined before, with some studies reporting that moderate-to-vigorous physical activity (MVPA) is positively associated with PF. However, it is unclear whether the observed associations differ between men and women. In this study, we investigated the associations of objectively measured MVPA, light physical activity (LPA), and sedentary time (ST) with different PF levels in older Japanese men and women. Subjects and Methods: A total of 810 community-dwelling subjects aged 65–75 years were investigated (52.1% women, 47.9% men). The PF variables included grip strength, one-leg standing, usual and maximum walking speeds, and chair-standing time. PA (MVPA, LPA, and ST) and the number of steps taken daily were assessed for seven consecutive days by a tri-axial accelerometer. We determined the sex-specific quartiles of MVPA, LPA, and ST and analyzed their associations with physical function in separate models for each exposure measure. Results: In the crude analysis, MVPA was significantly associated with all PF variables in the men, and with the usual walking speed, max. walking speed, and chair-standing time in the women. Neither LPA nor ST was significantly associated with any PF variables. After adjusting potential confounding factors, significant associations between MVPA and usual walking speed remained in the men and women. Conclusions: Only greater moderate-to-vigorous physical activity (MVPA) was significantly associated with higher levels of PF variables in both men and women. Thus, time spent in moderate-to-vigorous physical activity (MVPA) can help older adults maintain or improve their physical function.

Difference in sarcopenia characteristics associated with physical activity and disability incidences in older adults

BACKGROUND

Deteriorated skeletal muscle condition, including sarcopenia, is a risk factor for disability in older adults. Promoting physical activity is a useful treatment for sarcopenia. However, optimal intensity of physical activity according to sarcopenia characteristics is unclear.

METHODS

This longitudinal cohort study enrolled 2149 community-dwelling older adults (women 55.7%, mean age: 75.5 ± 4.0 years). Five-year disability incidence defined by Japanese long-term care insurance certification and accelerometer-measured physical activities (light-intensity physical activity [LPA] and moderate-to-vigorous intensity physical activity [MVPA]), which were adjusted for potential confounders, was analysed using cox-proportional hazard model stratified by sarcopenia characteristics based on the diagnostic algorithm by the Asian working group for sarcopenia (robust, low physical function, low muscle mass, and sarcopenia). The sarcopenia group was defined as low muscle mass and low physical function (weakness and/or slowness). The low muscle mass and low physical function groups were each defined by these characteristics alone. Muscle mass was analysed via bioelectrical impedance analysis. Each intensity of physical activity times was divided by median values.

RESULTS

The disability incidence rate was 15.4%, excluding those who could not be followed up. Mean LPA times were 43.8 ± 18.0, 45.6 ± 17.5, 45.4 ± 16.6, 40.8 ± 18.6, and 41.4 ± 18.5 min/day and MVPA times were 24.6 ± 17.6, 26.3 ± 18.3, 27.2 ± 17.3, 21.6 ± 16.3, and 21.5 ± 16.4 min/day in all participants, the robust, low muscle mass, low physical function, and sarcopenia groups, respectively. For all participants, higher MVPA was associated with disability incidence [hazard ratios (HR), 0.63; 95% confidence interval (95% CI), 0.49-0.81; P < 0.001], whereas higher LPA showed no association (HR, 0.86; 95% CI, 0.68-1.10; P = 0.22). Higher LPA was associated in the sarcopenia group (HR, 0.35; 95% CI, 0.15-0.85; P = 0.019), and MVPA was associated in the robust (HR, 0.58; 95% CI, 0.39-0.87; P = 0.008) and low physical function (HR, 0.66; 95% CI, 0.45-0.98; P = 0.040) groups. Both LPA and MVPA showed no association in the low muscle mass group. The P values for interactions between sarcopenia characteristics and physical activity were 0.017 for LPA and 0.014 for MVPA.

CONCLUSIONS

The LPA was associated with a lower risk of disability in older adults with sarcopenia, whereas MVPA was associated in subjects with robust and low physical function. Our findings indicate a need for individualized approaches to prevent disability based on muscle condition.

A Cross-Sectional Study on the Characteristics of Physical Activity in Pre-Frail Older Adults

This cross-sectional study aimed to characterize the physical activity (PA) of older adults with pre-frail status by examining sedentary behavior (SB) and PA using triaxial accelerometer data, with non-frail older adults as the control group. In this study, we divided the study participants into older adults who regularly participated in self-initiated citizen group exercise activities and those who did not. Data were collected between September and December 2017. We analyzed data from 256 older adults (women: 86.3%) aged ≥65 years. The interaction effect of participation status (participation and non-participation group) and frailty status (pre-frail and non-frail group) for moderate-to-vigorous PA (F = 9.178, p = 0.003) and daily mean number of steps (F = 9.351, p = 0.002) was significant. For the participation group, there was no difference between pre-frail older adults and non-frail older adults regarding length of SB and PA time, indicating that PA level was maintained in the participating pre-frail older adults. In contrast, moderate-to-vigorous PA and daily mean number of steps were low in pre-frail older adults who did not participate in the activities. The opportunity to participate in self-initiated group exercise activities and other PAs in the community may help pre-frail older adults maintain their PA.

Replacing sedentary time for physical activity on bone density in patients with chronic kidney disease

INTRODUCTION

This study aimed to examine the cross-sectional associations of sedentary time and physical activity time with bone density in patients with chronic kidney disease (CKD). The isotemporal substitution (IS) modeling was used to estimate the beneficial effects of behavioral changes (e.g., replacing sedentary time with physical activity time) on bone density in these patients.

MATERIALS AND METHODS

A total of 92 patients with CKD (age: 65 ± 9 years; estimated glomerular filtration rate: 57 ± 22 mL/min/1.73 m²) were included in this cross-sectional study. The times spent in sedentary behavior (SB), light-intensity physical activity (LPA), and moderate- to vigorous-intensity physical activity (MVPA) were assessed using a triaxial accelerometer. Through quantitative ultrasound measurements, the stiffness index, as a measure of bone density, was calculated using the speed of sound and broadband ultrasound attenuation.

RESULTS

In multivariate analyses, the stiffness index was beneficially associated with the MVPA time (β = 0.748), but was not significantly associated with the SB and LPA times. The IS models showed that replacing 10 min/day of SB with the equivalent LPA time was not significantly associated with the stiffness index; however, replacing 10 min/day of SB with the equivalent MVPA time was beneficially associated with the stiffness index (β = 0.804).

CONCLUSION

These results suggest that a small increase in MVPA time (e.g., 10 min/day) may attenuate the decline in bone density in patients with CKD. Our findings may provide insight for the development of novel strategies for improving bone health in patients with CKD.

Cardiovascular risk and functional burden at midlife: Prospective associations of isotemporal reallocations of accelerometer-measured physical activity and sedentary time in the CARDIA study

Cardiovascular risk and functional burden, or the accumulation of cardiovascular risk factors coupled with functional decline, may be an important risk state analogy to multimorbidity. We investigated prospective associations of sedentary time (ST), light intensity physical activity (LPA), and moderate to vigorous intensity physical activity (MVPA) with cardiovascular risk and functional burden at midlife. Participants were 1648 adults (mean ± SD age = 45 ± 4 years, 61% female, 39% Black) from Coronary Artery Risk Development in Young Adults (CARDIA) who wore accelerometers in 2005-2006 and 2015-2016. Cardiovascular risk and functional burden was defined as ≥2 cardiovascular risk factors (untreated/uncontrolled hypertension and hypercholesterolemia, type 2 diabetes, reduced kidney function) and/or functional decline conditions (reduced physical functioning and depressive symptoms). Prospective logistic regression models tested single activity, partition, and isotemporal substitution associations of accelerometer-measured ST, LPA, and MVPA with cardiovascular risk and functional burden 10 years later. In isotemporal models of baseline activity, reallocating 24 min of ST to MVPA was associated with 15% lower odds of cardiovascular risk and functional burden (OR: 0.85; CI: 0.75, 0.96). Reallocating 24 min of LPA to MVPA was associated with a 14% lower odds of cardiovascular risk and functional burden (OR: 0.86; CI: 0.75, 0.99). In longitudinal isotemporal models, similar beneficial associations were observed when 10-year increases in MVPA replaced time in ST or LPA. Findings suggest that maintaining an MVPA dose reflecting daily physical activity recommendations in early midlife is associated with lower odds of cardiovascular risk and functional burden later in midlife.

Physical Activity, Sedentary Behavior, and Skeletal Muscle Strength in Patients With Chronic Kidney Disease: An Isotemporal Substitution Approach

OBJECTIVE

Insufficient physical activity and excessive sedentary behavior can contribute to decreased skeletal muscle strength, which is strongly associated with increased mortality in patients with chronic kidney disease (CKD). However, the potential impact of replacing sedentary behavior with physical activity on skeletal muscle strength remains unclear in these individuals. The purpose of this study was to examine the associations of physical activity, sedentary behavior, and skeletal muscle strength in patients with CKD using an isotemporal substitution model to estimate the associations on replacing time from one behavior to another while keeping the total time and other behaviors fixed.

METHODS

A total of 108 patients with CKD (mean age = 65 [SD = 9] y; mean estimated glomerular filtration rate = 57 [SD = 22] mL/min/1.73 m2) participated in this cross-sectional analysis study. The time spent in sedentary behavior, light-intensity physical activity, and moderate- to vigorous-intensity physical activity (MVPA) was assessed using a triaxial accelerometer. Handgrip strength, isometric knee extension strength, and 30-second chair stand test were used to measure skeletal muscle strength.

RESULTS

In multivariate analyses (single-factor and partition models), the time spent in MVPA was beneficially associated with both isometric knee extension strength and 30-second chair stand test. Furthermore, the isotemporal substitution model found that replacing 10 min/d of sedentary behavior or light-intensity physical activity with equivalent MVPA time was beneficially associated with both isometric knee extension strength and 30-second chair stand test.

CONCLUSION

These cross-sectional findings indicate that MVPA time is beneficially associated with lower extremity muscle strength and that a slight increase in the MVPA time may contribute to maintaining skeletal muscle strength in patients with CKD.

IMPACT

Increasing the time spent in MVPA (10 min/d) may be a feasible strategy in patients with CKD who have a high prevalence of impaired physical function.

Preoperative physical activity predicts postoperative functional recovery in gastrointestinal cancer patients

PURPOSE

The present study aimed to investigate the association between preoperative physical activity (PA) and postoperative functional recovery in gastrointestinal cancer patients.

MATERIALS AND METHODS

In this prospective study, we included 101 patients who underwent colorectal or gastric cancer surgery. Primary outcome was 6-minute walk distance (6MWD) decline ratio ((postoperative 6MWD value - preoperative 6MWD value)/preoperative 6MWD value × 100 (%)), which was determined as postoperative functional recovery. Patients were divided into two groups according to the median of 6MWD decline ratio: above the median (non-decline group) and below the median (decline group). The International Physical Activity Questionnaire (IPAQ-SV) (the usual seven-day short version) was used to assess preoperative PA and sedentary time. Multivariate logistic regression analysis was performed to identify predictive factors of postoperative functional recovery.

RESULTS

Preoperative PA (odds ratio (OR): 3.812; 95% confidence interval (CI): 1.326-10.956; p = 0.01), 6MWD (OR: 1.006; 95% CI: 1.002-1.011; p < 0.01), C-reactive protein (OR: 4.138; 95% CI: 1.383-12.377; p = 0.01), and combined resection (OR: 3.425; 95% CI: 1.101-10.649; p = 0.03) were associated with postoperative functional recovery.

CONCLUSIONS

Preoperative PA is a predictor of postoperative functional recovery in patients who undergoing gastrointestinal cancer surgery.Implications for rehabilitationThe association between preoperative physical activity (PA) and postoperative functional recovery has been unclear in gastrointestinal cancer patients.We indicated that preoperative PA predicts postoperative functional recovery.Patients who low preoperative PA need to be monitored carefully in the postoperative course.Patients with low preoperative PA may need enhanced postoperative rehabilitation to reduce postoperative functional decline.

Associations of accelerometer-determined sedentary behavior and physical activity with physical performance outcomes by race/ethnicity in older women

To determine the cross-sectional associations of accelerometer-measured time spent in physical activity intensity categories (sedentary, low and high light intensity, or moderate to vigorous intensity physical activity (MVPA) with physical performance outcomes [stair climb ascent, 40 foot walk test, and short physical performance battery (SPPB)] in older women and examine differences by race/ethnicity. Data were from 1,256 Study of Women's Health Across the Nation (SWAN) participants [aged 64.9 (2.7) years at Visit 15 (2015-16); 54.1% non-White]. Three sets of adjusted multivariable linear or logistic regression models were built to test the study objectives using the backward elimination approach to identify relevant covariates. In the full analytic sample, a 10 min increment in MVPA was related to faster performance on the stair climb [β = -0.023 (95% CI: -0.04, -0.005) seconds] and 40 foot walk test [β = -0.066 (95% CI: -0.133, -0.038) seconds], and a 9% lower odds [OR: 0.91; 95% CI: 0.87, 0.96; p = 0.004] of limitations based on the SPPB. Statistically significant differences by race/ethnicity were found for the stair climb ascent time as MVPA was associated with better performance for White, Chinese, and Japanese participants while high light intensity physical activity, but not MVPA, was deemed beneficial in Black women. Findings from the isotemporal substitution models were consistent. Findings further support the importance of MVPA on physical performance outcomes in older women. Further research is needed to examine the complex associations between physical (in)activity and physical performance outcomes by race/ethnicity to provide more targeted recommendations.

The association of objectively measured physical activity and sedentary behavior with skeletal muscle strength and muscle power in older adults: A systematic review and meta-analysis

BACKGROUND

Engaging in physical activity (PA) and avoiding sedentary behavior (SB) are important for healthy ageing with benefits including the mitigation of disability and mortality. Whether benefits extend to key determinants of disability and mortality, namely muscle strength and muscle power, is unclear.

AIMS

This systematic review aimed to describe the association of objective measures of PA and SB with measures of skeletal muscle strength and muscle power in community-dwelling older adults.

METHODS

Six databases were searched from their inception to June 21^st, 2020 for articles reporting associations between objectively measured PA and SB and upper body or lower body muscle strength or muscle power in community dwelling adults aged 60 years and older. An overview of associations was visualized by effect direction heat maps, standardized effect sizes were estimated with albatross plots and summarized in box plots. Articles reporting adjusted standardized regression coefficients (β) were included in meta-analyses.

RESULTS

A total of 112 articles were included representing 43,796 individuals (range: 21 to 3726 per article) with a mean or median age from 61.0 to 88.0 years (mean 56.4 % female). Higher PA measures and lower SB were associated with better upper body muscle strength (hand grip strength), upper body muscle power (arm curl), lower body muscle strength, and lower body muscle power (chair stand test). Median standardized effect sizes were consistently larger for measures of PA and SB with lower compared to upper body muscle strength and muscle power. The meta-analyses of adjusted β coefficients confirmed the associations between total PA (TPA), moderate-to-vigorous PA (MVPA) and light PA (LPA) with hand grip strength (β = 0.041, β = 0.057, and β = 0.070, respectively, all p ≤ 0.001), and TPA and MVPA with chair stand test (β = 0.199 and β = 0.211, respectively, all p ≤ 0.001).

CONCLUSIONS

Higher PA and lower SB are associated with greater skeletal muscle strength and muscle power, particularly with the chair stand test.

The Feasibility and Effectiveness of a Community-Based Intervention to Reduce Sedentary Behavior in Older Adults

The purpose of this study was to examine the effectiveness and feasibility of translating a 4-week "Stand Up and Move More" (SUMM) intervention by state aging units to older adults (N = 56, M age = 74 years). A randomized controlled trial assessed sedentary behavior, physical function, and health-related quality of life (HRQoL) before and after the intervention. Participants included healthy community-dwelling, sedentary (sit > 6 hr/day) and aged ≥ 55 years adults. For the primary outcome, the SUMM group (n = 31) significantly (p < .05) reduced total sedentary time post-intervention by 68 min/day on average (Cohen's d = -0.56) compared with no change in the wait-list control group (n = 25, Cohen's d = 0.12). HRQoL and function also improved (p < .05) in the SUMM group post-intervention. Workshop facilitators indicated the intervention was easy to implement, and participants expressed high satisfaction. The SUMM intervention reduced sedentary time, improved physical function and HRQoL, and was feasible to implement in community settings.

Correlates of change in accelerometer-assessed total sedentary time and prolonged sedentary bouts among older English adults: results from five-year follow-up in the EPIC-Norfolk cohort

BACKGROUND

Development of effective strategies to reduce sedentary time among older adults necessitates understanding of its determinants but longitudinal studies of this utilising objective measures are scarce.

METHODS

Among 1536 older adults (≥60 years) in the EPIC-Norfolk study, sedentary time was assessed for seven days at two time-points using accelerometers. We assessed associations of change in total and prolonged bouts of sedentary time (≥ 30 minutes) with change in demographic and behavioural factors using multi-level regression.

RESULTS

Over follow-up (5.3±1.9 years), greater increases in total sedentary time were associated with older age, being male, higher rate of increase in BMI, lower rate of increase in gardening (0.5 min/day/yr greater sedentary time per hour/week/yr less gardening, 95% CI 0.1, 1.0), a lower rate of increase in walking (0.2 min/day/yr greater sedentary time per hour/week/yr less walking, 95% CI 0.1, 0.3) and a higher rate of increase in television viewing. Correlates of change in prolonged sedentary bouts were similar.

CONCLUSION

Individuals in specific sub-groups (older, male, higher BMI) and who differentially participate in certain behaviours (less gardening, less walking and more television viewing) but not others increase their sedentary time at a higher rate than others; utilising this information could inform successful intervention content and targeting.

Associations of sitting and physical activity with grip strength and balance in mid-life: 1970 British Cohort Study

Strength and balance training are now recommended in many physical activity (PA) guidelines. However, it is unclear whether these recommendations are applicable to middle-aged adults. We aimed to examine the associations of sitting and physical activity times with grip strength and standing balance performance in mid-life. Up to 4726 participants from the 1970 British Cohort study, with data on sitting and activity (measured using a thigh-worn accelerometer (activPAL3-micro)), grip strength and balance times at age 46 years were included in analyses. Associations of sitting, moderate-vigorous, and total PA times with grip strength and balance performance were tested using linear and multinomial logistic regression models, respectively. Greater time spent sitting was associated with weaker grip strength even after adjustment for potential confounders and MVPA time (fully adjusted regression coefficient: -0.51 kg (95% CI: -0.63, -0.39) per 1-hour sitting/day). Associations of PA time with grip strength were not independent of sitting time. There was only a weak association between sitting time and balance performance but greater MVPA and total PA times were associated with higher relative risks of successfully balancing for 30 seconds with eyes closed (vs poor balance). However, these associations were fully attenuated after adjustments for covariates. In summary, among a sample of middle-aged adults a robust association between sitting time and grip strength was observed. These findings suggest potential benefits of actively promoting less sitting alongside activities that specifically benefit muscle strength and balance performance in mid-life to ensure that people maintain all important aspects of their physical capability as they age.

Objectively Measured Sedentary Behavior and Physical Fitness in Adults: A Systematic Review and Meta-Analysis

Background: Sedentary behavior has been considered an independent risk factor to health. The aim of this systematic review and meta-analysis was to examine associations between objectively measured sedentary time and physical fitness components in healthy adults. Methods: Four electronic databases (Web of Science, Scopus, Pubmed and Sport Discus) were searched (up to 20 September 2020) to retrieve studies on healthy adults which used observational, cohort and cross-sectional designs. Studies were included if sedentary time was measured objectively and examined associations with the health- or skill-related attributes of physical fitness (e.g., muscular strength, cardiorespiratory fitness, balance). After applying additional search criteria, 21 papers (11,101 participants) were selected from an initial pool of 5192 identified papers. Results: Significant negative associations were found between total sedentary time with cardiorespiratory fitness (r = −0.164, 95%CI: −0.240, −0.086, p < 0.001), muscular strength (r = −0.147, 95%CI: −0.266, −0.024, p = 0.020) and balance (r = −0.133, 95%CI: −0.255, −0.006, p = 0.040). Conclusions: The evidence found suggests that sedentary time can be associated with poor physical fitness in adults (i.e., muscular strength, cardiorespiratory fitness and balance), so strategies should be created to encourage behavioral changes.

Association of objectively measured physical activity with combined bilateral knee and low-back pain in older adults with knee osteoarthritis: A cross-sectional study

OBJECTIVE

Knee pain (KP) and low-back pain (LBP) are common sites of pain and major public health issues among older adults. We investigated the combined association of bilateral KP and LBP with objectively measured physical activity (PA) among adults with knee osteoarthritis (OA).

METHODS

We recruited 150 knee OA adults and measured steps and PA intensity, including sedentary behavior (SB), low PA (LPA), and moderate-to-vigorous PA, using an accelerometer. KP and LBP were measured using a numerical rating scale. They were classified into 4 groups based on the presence of KP and LBP: with the only unilateral KP (UKP), with the combined UKP and LBP (UKP and LBP), with the bilateral KP (BKP), and with the combined bilateral KP and LBP (BKP and LBP). One-way analysis of covariance was performed to compare physical activity variables (intensity or steps) between the four groups.

RESULTS

Overall, 126 patients were enrolled. The prevalence of UKP, BKP, UKP and LBP, and BKP and LBP were 29.4%, 23.8%, 18.3%, and 28.6%. The proportion of SB was higher in the BKP and LBP group than in the other groups (F = 6.51, p < 0.01). The proportion of LPA was lower in the BKP and LBP group than in the other groups (F = 6.21, p < 0.01).

CONCLUSIONS

The proportions of SB and LPA were significantly worse in knee OA adults with BKP and LBP than in those with UKP. Our findings may be a basis for considering knee OA adults for improving PA.

The association between recreational screen time and cancer risk: findings from the UK Biobank, a large prospective cohort study

Background

Evidence is suggestive of sedentary behaviour being associated with an increased risk of endometrial cancer, but the evidence base is too limited to draw any conclusions for other cancers. The aim of the study was to investigate the association between recreational screen time and site-specific cancer risk.

Methods

We analysed data from the prospective UK Biobank cohort study. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for associations between daily recreational screen time (including television (TV) viewing time, computer use time and total screen time) and site-specific cancer risk. Partition models and isotemporal substitution models investigated the impact of substituting recreational screen time with physical activity.

Results

During a mean follow-up of 7.6 years, 28,992 incident cancers were identified among 470,578 adults. A 1-h increase in daily TV viewing time was associated with higher risks of oropharyngeal, oesophago-gastric and colon cancer in fully adjusted models. Participants who reported ≤1, compared with 1- ≤ 3, hours/day of TV viewing time had lower risks of lung, breast, and oesophago-gastric cancer. Findings were inconsistent for daily recreational computer use and daily total recreational screen time. The majority of observed associations were small, and were attenuated after excluding cancers diagnosed within the first two years of follow-up, except for oesophago-gastric and colon cancers (HR 1.05, 95% CI: 1.01, 1.10; and HR 1.04, 95% CI: 1.01, 1.07 per 1-h increase in daily TV viewing time, respectively). However, isotemporal substitution models showed reduced risk of some site-specific (oropharyngeal, lung, breast and colorectal) cancers when replacing 1-h/day of TV viewing with 1-h of moderate-intensity physical activity or walking.

Conclusions

Our findings show that daily recreational screen time, particularly TV viewing, was associated with small increased risks of oesophago-gastric and colon cancer. Replacing 1-h/day of TV viewing with 1-h of moderate-intensity physical activity or walking was associated with lower risk of oropharyngeal, lung, breast and colorectal cancers. Further research from other large prospective cohort studies is required, while mechanistic research is warranted to enhance the biological plausibility of these findings.

Sedentary behaviour, physical activity, and renal function in older adults: isotemporal substitution modelling

Background

Physical inactivity and sedentary behaviour (too much sitting) can contribute to renal dysfunction. However, the potential benefits of behavioural change (e.g. replacing sedentary behaviour with physical activity) on renal function are not well understood. We used isotemporal substitution to model potential impacts of behaviours on renal function by replacing time spent in one behaviour to another.

Methods

In 174 older Japanese adults (age, 50–83 years; females, 76%), the time spent in sedentary behaviour, light-intensity physical activity (LPA), and moderate- to vigorous-intensity physical activity (MVPA) were assessed using an uniaxial accelerometer. Renal function was evaluated by the estimated glomerular filtration rate (eGFR) from serum creatinine and cystatin C levels.

Results

In univariate analyses, eGFR was significantly, albeit weakly, correlated with time spent in sedentary behaviour (r_s = − 0.229), LPA (r_s = 0.265), and MVPA (r_s = 0.353). In the isotemporal substitution models, replacement of 30 min/day of sedentary behaviour with an equivalent LPA time was not significantly associated with eGFR (β = 2.26, p = 0.112); however, replacement with an equivalent time of MVPA was beneficially associated with eGFR (β = 5.49, p < 0.05).

Conclusions

These cross-sectional findings suggest that sedentary behaviour (detrimentally) and physical activity (beneficially) may affect renal function and that replacing sedentary behaviour with MVPA may benefit renal health in older adults.

Clustering of Domain-Specific Sedentary Behaviors and Their Association With Physical Function Among Community-Dwelling Older Adults

BACKGROUND

The present study examined the cluster of domain-specific sedentary behaviors (SBs) and their associations with physical function among community-dwelling older adults to identify the target groups that require intervention for SBs.

METHODS

A total of 314 older adults who participated in a population-based cross-sectional survey and an on-site functional assessment in Matsudo City in Chiba participated in this study. Participants were asked to report the daily average of 6 domain-specific SBs. To identify the cluster of domain-specific SBs, hierarchical cluster analysis was performed using the Ward method. Analysis of covariance adjusted for sociodemographic factors, exercise habit, chronic disease, and total SB time was performed to examine the associations between each cluster and physical functional status.

RESULTS

The average age of the participants was 74.5 (5.2) years. The 4 clusters identified were leisure cluster, low cluster, work and personal computer use cluster, and television viewing cluster. The analysis of covariance adjusted for covariates showed that grip strength (P = .01), maximum walking speed (P = .03), and 1-leg standing time (P = .03) were significantly poorer in the television viewing cluster than other clusters.

CONCLUSIONS

It has been concluded that the television viewing group identified as a high-risk group of physical functional decline; therefore, interventions targeting this group are needed to prevent physical functional decline.

Associations of physical activity in detailed intensity ranges with body composition and physical function. a cross-sectional study among sedentary older adults

BACKGROUND

Physical activity is crucial to maintain older adults' health and functioning, but the health benefits of particular activity intensities remain unclear. The aim of this cross-sectional study was to peruse the distribution of physical activity, and to investigate the associations of particular physical activity intensities with body composition and physical function among older adults.

METHODS

The sample comprised of 293 community-dwelling sedentary or at most moderately active older adults (42% men, mean age 74 ± 4 years). Physical activity was measured with a hip-worn tri-axial accelerometer over seven consecutive days, and investigated in detailed intensity range and in categories of sedentary, light and moderate-to-vigorous activity. Fat percent and appendicular lean mass were measured with DXA. Physical function was assessed by six-minutes walking test (6-min walk), maximal walking speed over 10 m (10-m walk) and Short Physical Performance Battery (SPPB). Associations were estimated with partial correlation adjusted for sex and age.

RESULTS

Participants spent on average 602 min per day sedentary, 210 min in light activity and 32 min in moderate-to-vigorous activity. Light and moderate-to-vigorous activity were negatively associated with fat percent (r = - 0.360 and r = - 0.384, respectively, p < 0.001 for both), and positively with SPPB, 10-m walk and 6-min walk results (r = 0.145-0.279, p < 0.01, for light and r = 0.220-0.465, p < 0.001, for moderate-to-vigorous activity). In detailed investigation of the intensity range, associations of physical activity with fat percent, 6-min walk and 10-m walk were statistically significant from very light intensity activity onward, whereas significant associations between physical activity and SPPB were observed mostly at higher end of the intensity range. Sedentary time was positively associated with fat percent (r = 0.251, p < 0.001) and negatively with 6-min walk (r = - 0.170, p < 0.01).

CONCLUSION

Perusing the physical activity intensity range revealed that, among community-dwelling sedentary or at most moderately active older adults, physical activity of any intensity was positively associated with lower fat percent and higher walking speed over long and short distances. These findings provide additional evidence of the importance of encouraging older adults to engage in physical activity of any intensity. More intervention studies are required to confirm the health benefits of light-intensity activity.

Physical multimorbidity and sedentary behavior in older adults: Findings from the Irish longitudinal study on ageing (TILDA)

BACKGROUND

Physical multimorbidity, defined as the presence of two or more chronic physical conditions, is widespread and reduces life expectancy and quality of life in older adults. Sedentary behavior (SB) is increasingly identified as a risk factor for a range of chronic physical conditions, independent of physical activity.

OBJECTIVES

To investigate associations between physical multimorbidity and SB in older adults.

STUDY DESIGN

We used cross-sectional data from a population-based sample of 6903 adults aged ≥50 years who participated in the Irish Longitudinal Study on Ageing (TILDA) in 2009-2011. We conducted multivariable linear and logistic regression analyses to assess associations between multimorbidity and SB.

MAIN OUTCOME MEASURES

Self-reported minutes/day of SB and high SB (≥ 8 h/day).

RESULTS

We found that most of the 14 individual chronic physical conditions included here were associated with greater SB. Those with stroke (OR = 2.63, 95 % CI = 1.69, 4.10) and cirrhosis (OR = 2.53, 95 %CI = 1.19, 5.41) were the most likely to be classified with high SB. Time spent in SB and the prevalence of high SB increased linearly with number of chronic conditions. Multivariable regression models adjusting for sociodemographic and psychological factors, disability, social network, and physical activity showed that, compared with people with none, those with ≥4 chronic physical conditions had 1.45 times greater odds (OR = 1.45, 95 % CI = 1.09, 1.93) of high SB and higher mean minutes/day of SB (β = 21.37, 95 % CI = 5.53, 37.20).

CONCLUSIONS

Our results suggest that physical multimorbidity is associated with SB and highlight the need for prospective research to examine the directionality and mechanisms of these associations.

Effect of preoperative sedentary behavior on clinical recovery after total knee arthroplasty: a prospective cohort study

OBJECTIVES

Prolonged sedentary behavior (SB) may affect clinical improvements following total knee arthroplasty (TKA). We aim to assess preoperative SB effect on improvements in clinical outcomes after TKA. We hypothesized that patients with high proportion of preoperative SB have small improvements in clinical outcomes after TKA.

METHODS

We recruited 115 adults with knee osteoarthritis (OA), planning to undergo TKA. Knee-specific functional outcomes were assessed using the new knee society score (KSS), including total score, symptoms, patient satisfaction, patient expectations, and functional activities. Gait function was assessed using the timed up and go (TUG) test. SB was measured using a triaxial accelerometer. Multiple linear regression analysis was performed to investigate preoperative SB effect on improvements in clinical outcomes 6 months postoperatively by adjusting for several factors as potential confounders.

RESULTS

Of 115 patients, 82 were included. High proportion of preoperative SB had a significant negative effect on recovery at 6 months in the new KSS total score [β, -0.83, 95% confidence interval (CI), -1.53 to -0.12; p = 0.02], symptoms (-0.15, -0.28 to -0.02; p = 0.03), patient satisfaction (-0.22, -0.42 to -0.02; p = 0.03), and functional activities (-0.40, -0.76 to -0.04; p = 0.03) after adjusting for potential confounders.

CONCLUSIONS

A high proportion of preoperative SB was a risk factor for reduced improvements in knee-specific functional outcomes after TKA. To prevent poor functional recovery after TKA, it is essential to understand the preoperative lifestyle factors and intervene proactively during acute postoperative phase in patients with high SB proportion.Key Points• Preoperative high proportion of SB had a negative effect on improvement in new KSS total scores, symptoms, patient satisfaction, and functional activities.• When considering clinical outcomes after TKA, clinicians should closely monitor patients with high proportions of preoperative SB to prevent poor functional recovery.

The Sedentary Time and Physical Activity Levels on Physical Fitness in the Elderly: A Comparative Cross Sectional Study

Background: Ageing is a life-long process characterized by a progressive loss of physical fitness compromising strength, flexibility, and agility. The purpose of this study was to use accelerometry to examine the relationship between sedentary time, light physical activity (LPA), and moderate to vigorous physical activity (MVPA) with the elderly’s physical fitness. Additionally, we aimed to examine the association between the aforementioned variables on older adults who fulfilled global recommendations on physical activity for health and on those who did not fulfil these recommendations. Methods: Eighty-three elderly (mean ± SD: 72.14 ± 5.61 years old) of both genders volunteered to participate in this cross-sectional study, being divided into an active group (n = 53; 71.02 ± 5.27 years old) and an inactive group (n = 30; 74.13 ± 5.72 years old) according to the established guidelines. Sedentary and physical activity times were assessed using an ActiGraph^® GT1M accelerometer, whereas physical fitness was evaluated with the Senior Fitness Test. Results: MVPA time was correlated with lower body mass index (BMI) ((r_s = −0.218; p = 0.048; −0.3 < r ≤ −0.1 (small)) and shorter time to complete the agility test ((r_s = −0.367; p = 0.001; −0.5 < r ≤ −0.3 (low)). Moreover, MVPA time was positively correlated with aerobic endurance ((r_s = 0.397; p = 0.000; 0.5 < r ≤ 0.3 (low)) and strength ((r_s = 0.243; p = 0.027; 0.3 < r ≤ 0.1 (small)). In the inactive group, MVPA time was positively correlated with upper limb flexibility ((rs = 0.400; p = 0.028; 0.5 < r ≤ 0.3 (low)); moreover, sedentary time was negatively correlated with upper limb flexibility ((r = −0.443; p = 0.014; −0.5 < r ≤ −0.3 (low)), and LPA time was negatively correlated with BMI ((r = −0.423; p = 0.020; −0.5 < r ≤ −0.3 (low)). In the active group, MVPA time was correlated with lower BMI ((rs = −0.320; p = 0.020; −0.5 < r ≤ −0.3 (low)), and shorter time to complete agility test ((rs = −0.296; p = 0.031; −0.3 < r ≤ −0.1 (small)). Conclusions: Our results reinforce the importance of promoting MVPA practice among the elderly, thereby allowing physical fitness maintenance or improvement.

Effects of sedentary behavior and physical activity on sleep quality in older people: A cross-sectional study

The aim of this cross-sectional study was to investigate the influence of replacing sedentary time with time engaged in one of two levels of physical activity on sleep quality using an isotemporal substitution model. The participants were 70 community-dwelling older Japanese adults (approximately 70% female). Physical activity types were measured using a triaxial accelerometer and categorized based on intensity as sedentary, light-intensity, and vigorous-intensity. The Pittsburgh Sleep Quality Index assessed subjective sleep quality. Objective sleep parameters were assessed using an actigraph. A series of multi-linear regression models analyzed the statistical relationships. Our findings showed that replacing 30 min of sedentary activity per day with an equal period of light-intensity physical activity significantly influenced sleep quality parameters. However, there was no significant difference in sleep quality when light-intensity activity was replaced with vigorous-intensity activity. Engaging in one activity type means less available time for other types of activity; habitual replacement of sedentary activity with light-intensity physical activity might have long-term benefits on the sleep quality of older people.

Physical Activity and Sedentary Behavior Assessment: A Laboratory-Based Evaluation of Agreement between Commonly Used ActiGraph and Omron Accelerometers

Different models of accelerometer have the potential to provide a different estimate of the same physical activity or sedentary behavior. Our study compared the outputs of the Active Style Pro (ASP) and ActiGraph (AG) devices in assessing predicted metabolic equivalents (METs) for specific activities under laboratory conditions. Thirty healthy young adults wore two hip accelerometers (ASP and AG), simultaneously while performing twenty-two activities (eight sedentary, eight household, and six ambulatory activities) in a controlled laboratory setting. For the AG, predicted METs for each activity was calculated using four equations based on vertical-axis and vector magnitude data. Separate paired t-tests and Bland–Altman analysis examined the difference and agreement in METs between AG using four commonly used equations and ASP measurements for each activity. AG devices using different equations calculated significantly different outcomes for most activities compared with ASP devices. The smallest differences in predicted METs estimates between ASP and AG were observed for ambulatory activities. Ambulatory activities demonstrated the best agreement between ASP and AG regardless of which AG equation was used. Our findings can be used to assist researchers in their selection of accelerometer and output estimation equations for measuring physical activity and sedentary behavior in adults.

Assessing Physical Activity and Sedentary Behavior under Free-Living Conditions: Comparison of Active Style Pro HJA-350IT and ActiGraphTM GT3X

Various accelerometers have been used in research measuring physical activity (PA) and sedentary behavior (SB). This study compared two triaxial accelerometers—Active style Pro (ASP) and ActiGraph (AG)—in measuring PA and SB during work and nonwork days in free-living conditions. A total of 50 working participants simultaneously wore these two accelerometers on one work day and one nonwork day. The difference and agreement between the ASP and AG were analyzed using paired t-tests, Bland–Altman plots, and intraclass coefficients, respectively. Correction factors were provided by linear regression analysis. The agreement in intraclass coefficients was high among all PA intensities between ASP and AG. SB in the AG vertical axis was approximately 103 min greater than ASP. Regarding moderate-to-vigorous-intensity PA (MVPA), ASP had the greatest amount, followed by AG. There were significant differences in all variables among these devices across all day classifications, except for SB between ASP and AG vector magnitude. The correction factors decreased the differences of SB and MVPA. PA time differed significantly between ASP and AG. However, SB and MVPA differences between these two devices can be decreased using correction factors, which are useful methods for public health researchers.

Comparison of Older and Newer Generation Active Style Pro Accelerometers in Physical Activity and Sedentary Behavior Surveillance under a Free-Living Environment

Background. Comparability of accelerometers in epidemiological studies is important for public health researchers. This study aimed to compare physical activity (light, LPA; moderate, MPA; and moderate-to-vigorous, MVPA) and sedentary behavior (SB) data collected using two Omron triaxial accelerometer generations (Active style Pro, ASP) among a sample of Japanese workers in a free-living environment. Methods. Thirty active and sedentary workers (24–62 years) wore two types of ASP accelerometers, the HJA-350IT (350IT) and the HJA-750C (750C), simultaneously for seven consecutive days to represent a typical week. The accelerometers estimated daily average step counts and time spent per day in LPA, MPA, and MVPA. If a participant had data for ≥4 days (>10 h/day) it was considered valid. The difference and agreement between the two ASPs were analyzed using a paired t-test, intra-class correlation coefficients (ICC), and a Bland–Altman analysis in total and for each type of worker. Results. Among all workers, the 750C measured significantly (p < 0.05) less SB, MPA, MVPA, and more LPA compared with the 350IT. The agreements in ICC were high (ICC ≥ 0.94). Conclusions. Compared with the 350IT, the newer generation 750C ASP accelerometer may not provide equivalent estimates of activity time, regardless of the type of physical activity.

Land use proportion and walking: Application of isometric substitution analysis

Entropy measures of land use mix are a commonly used component of walkability. However, they present methodological challenges, and studies on their associations with walking have produced mixed findings. This study examined associations of the proportion of discrete land uses with walking, using isometric substitution models that take the complementary nature of land use proportions into account. Analysis of data collected from middle-aged adults living in Brisbane, Australia (n = 10,794) found that replacing residential or other land with commercial land was associated with higher levels of walking. The isometric substitution approach may explain the potential impact of land use changes on residents' walking.

Replacing sedentary time with physical activity: effects on health-related quality of life in older Japanese adults

Background

The isotemporal substitution (IS) approach can be used to assess the effect of replacing one activity with the equal duration of another activity on relevant outcomes. This study examined the associations of objectively assessed sedentary behavior (SB) and physical activity (PA) with health-related quality of life (HRQOL) in older Japanese adults, using the IS approach.

Methods

Participants were 287 older Japanese adults (aged 65–84 years) who wore accelerometers for at least 7 days. We calculated the average daily time spent in SB (≤1.5 METs); light-intensity PA (LPA: > 1.5 to < 3.0 METs); and moderate- to vigorous-intensity PA (MVPA: ≥3.0 METs) per day. HRQOL was assessed using the Medical Outcomes Survey Short Form-8 questionnaire.

Results

The IS models showed replacing SB or LPA with MVPA to be significantly associated with better physical component summary scores. Replacing SB with MVPA was marginally associated with better mental component summary scores.

Conclusion

These findings indicate that replacing SB with the same amount of MVPA may contribute to better physical HRQOL in older adults.

Let's walk! Age reattribution and physical activity among older Hispanic/Latino adults: results from the ¡Caminemos! Randomized trial

Background

Many older Hispanics/Latinos are physically inactive and suffer the harmful health consequences associated with prolonged periods of inactivity. Negative age attributions that equate getting older with “slowing down” reinforce this inactive behavior. We implemented a community-based exercise intervention among insufficiently active older Hispanics/Latinos with a randomized trial of an attribution-retraining program, ¡Caminemos! (Let’s Walk!), and measured the effect of the program on walking behavior.

Methods

Five hundred and seventy-two older Hispanics/Latinos (≥60 years) were enrolled in an exercise program that randomly assigned participants to the exercise class and one of two conditions: (a) treatment (attribution retraining to dispel the notion that physical activity inevitably ceases with age) or (b) control (generic health education). Data were collected at baseline and follow-up (1, 12, and 24 months). Physical activity was determined through pedometer data and the Yale Physical Activity Survey. We also measured the intervention effects on age-expectations, self-efficacy expectations, and outcome expectations for physical activity. Mixed-effects regression models were used to determine intervention effects on prospective measures of physical activity and intrapersonal expectations.

Results

The sample had a mean age of 73 years (SD = 6.8) and was 77% female, and 76% of the sample reported income <$20,000. At baseline, control and treatment groups walked about 3000 steps/day. By 24 months, participants in both arms of the intervention maintained greater than 10,000 mean steps/day, but the difference between the groups was not statistically significant. In analyses adjusted for age, sex, education, income, health status, and acculturation, participants in both trial arms increased their mean numbers of steps at 12 and 24 months, with the treatment group showing a greater number of mean steps compared to the controls at 12 months.

Conclusions

In this group of physically inactive older Hispanics/Latinos, attribution retraining in combination with an exercise class was superior to the exercise class alone with regard to increasing walking behavior. This success was sustained at 12 months (the pre-defined primary study outcome) but not at 24 months. For older Hispanics/Latinos, enrollment in an attribution-retraining exercise program can improve an inactive lifestyle.

Trial registration

clinicaltrials.gov identifier: NCT00183014.

The association of locomotive and non-locomotive physical activity measured by an accelerometer with functional fitness in healthy elderly men: a pilot study

PURPOSE

The purpose of this study was to investigate the relationship of various aspects of daily physical activity, such as the number of steps, time spent in moderate to vigorous intensity physical activity (MVPA), and locomotive and non-locomotive MVPA measured by a triaxial accelerometer, with the functional fitness in healthy elderly men.

METHODS

The subjects of this study were 22 healthy elderly men aged over 65 years. The participants wore a triaxial accelerometer for two weeks to estimate their daily physical activities. The level of functional fitness was measured based on "National Fitness Award 100 in Korea" immediately after the measurement of two weeks of daily physical activities.

RESULTS

The results showed that active healthy elderly men with more than 6,500 walking steps per day and more than 60 min per day spent in MVPA showed a significantly higher 2-min marching in place and index of cardiorespiratory endurance compared to less physically active participants. Particularly, locomotive MVPA was significantly associated with cardiorespiratory endurance levels (r = 0.50), whereas non-locomotive MVPA was not associated with other measurements of functional fitness.

CONCLUSION

Increased MVPA time, especially the locomotive MVPA, can effectively suppress the decrease in cardiorespiratory endurance level in elderly men. However, no association was observed between non-locomotive MVPA, such as household activities, and functional fitness in healthy elderly men.