Associations of Mutually Exclusive Categories of Physical Activity and Sedentary Time With Metabolic Syndrome in Older Adults: An Isotemporal Substitution Approach.

The aim of this study was to examine, theoretically, how reallocating time between the intensity of mutually exclusive categories of physical activity and sedentary behavior time is associated with metabolic syndrome. Four hundred and six older adults (61.6% women) from the second wave of the EpiFloripa Aging Cohort Study were included in the study (mean age 71.7 ± 5.9 years). Isotemporal substitution analysis showed a decrease of 35% (odds ratio: 0.65; 95% confidence interval [0.45, 0.96]) in the risk for metabolic syndrome when replacing 30 min/day of sedentary behavior with an equivalent amount of moderate to vigorous physical activity. Furthermore, it has been observed that older adults classified as low sedentary behavior and physically active were 57% less likely to have metabolic syndrome than participants classified as high sedentary and physically inactive (odds ratio: 0.43; 95% confidence interval [0.19, 0.97]). This study highlights the importance of behavioral categories that may emerge concerning the interrelationships of physical activity and health in older adults, having important implications for future health intervention programs.

Associations of daily activities measured by a pattern-recognition activity monitor with overall and abdominal obesity in older people: the IMPACT65+ study.

OBJECTIVES: The aims of the present study were: (i) to analyze the associations of the time spent in daily activities (i.e., lie, recline, passive sit, active sit, stand, walk at slow pace, walk at average pace, walk at brisk pace, and other activities) with body mass index (BMI) and waist circumference (WC); and (ii) to examine how theoretically reallocating time between these daily activities is associated with BMI and WC. METHODS: The sample included 437 older adults (288 women), aged 65 to 92 years, participating in the IMPACT65+ study. The time in daily activities was assessed by the Intelligent Device for Energy Expenditure and Activity (IDEEA). BMI and WC were measured following standardized procedures. Associations of daily activities with BMI and WC were examined using linear regression models adjusting for potential confounders. Isotemporal substitution models were performed to estimate the theoretical effect of replacing one activity with another activity while holding total time constant. RESULTS: The time spent lying and reclining was associated with increased BMI and WC, while the time spent standing, walking at average pace, and walking at brisk pace was associated with decreased BMI and WC. Isotemporal substitution analyses revealed significant hypothetical reductions in BMI and WC when reallocating 15 min from lying or reclining to standing or walking at average pace. Moreover, replacing 15 min from any sedentary activity or light physical activity (except for walking at average pace) with an equal amount of time in walking at brisk pace was associated with lower BMI and WC. CONCLUSIONS: This is the first study examining the activity specific and isotemporal associations of daily behaviors (considering body postures and movements) with overall and abdominal obesity in older people. The results could be used in the development of specific recommendations encouraging an active lifestyle in older people.

Need to promote healthy lifestyle as primary prevention to the COVID-19 and to improve the immune response to vaccines.

Letter to the editor.

Clinical and Ambulatory Gait Speed in Older Adults: Associations With Several Physical, Mental, and Cognitive Health Outcomes.

BACKGROUND: Although clinical gait speed may indicate health and well-being in older adults, there is a lack of studies comparing clinical tests with ambulatory gait speed with regard to several health outcomes. OBJECTIVE: The objective of this study was to examine the associations of clinical gait speed, measured by the 2.44-m walk test and the ambulatory gait speed with several physical, mental, and cognitive health outcomes in older adults. DESIGN: A cross-sectional design was used. METHODS: The study population comprised 432 high-functioning, community-dwelling older adults (287 women) aged between 65 and 92 years. Clinical and ambulatory gait speeds were measured using the 2.44-m walk test and a portable gait analysis device, respectively. Multiple linear regressions were used to examine the association of clinical and ambulatory gait speeds with several health outcomes (body mass index, waist circumference, systolic and diastolic blood pressure, chronic conditions, self-rated health, exhaustion, upper- and lower-body strength, physical and mental health status, cognitive status, and self-rated cognitive status). RESULTS: The results showed that the average gait speed for clinical and ambulatory measures cannot be directly compared. Clinical gait speed was associated with 7 health outcomes, and the ambulatory gait speed was associated with 6 health outcomes. The significant associations between measures of gait speed and the health outcomes converged in 5 of the 13 health outcomes studied; however, the strength of associations was singly different between measures. LIMITATIONS: The short monitoring time, the inability to distinguish between the ambulatory gait speed inside the home and outdoor gait speed, and the under-representative sample are limitations of the study. CONCLUSION: The results indicated differences in the number and strength of associations between clinical and ambulatory gait speed. Both measures have construct validity because they have been associated with physical and health outcomes; however, they may have different predictive validity. Further research should be conducted to compare their predictive validity in longitudinal designs.

Criterion Validity of the Sedentary Behavior Question From the Global Physical Activity Questionnaire in Older Adults.

BACKGROUND: To assess the validity of the single question to determine sedentary behavior (SB) by using the Global Physical Activity Questionnaire (GPAQ) in older adults. METHODS: The sample included 163 participants (96 women) aged 65-92 years. Self-reported SB was obtained from the GPAQ. Objectively measured SB was assessed using the Intelligent Device for Energy Expenditure and Activity. Participants wore the Intelligent Device for Energy Expenditure and Activity continuously during 2 consecutive days while following their daily routine. The relative validity was assessed using the Spearman rank correlation coefficient (ρ), and the agreement was examined using mean bias and 95% limit of agreement with the Intelligent Device for Energy Expenditure and Activity as reference. RESULTS: The results showed small correlations (ρ = .291, P < .001) between the SB from the GPAQ and the objective measures, and ranged from ρ = .217 to ρ = .491 depending on the potential moderator. Similarly, the GPAQ underestimates the SB for approximately 2 hours per day in older adults (limit of agreement = -7.3 to 3.4 h/d). CONCLUSION: The GPAQ may not be the most suitable questionnaire for measuring SB in this population and should be used with caution because those studies that use this questionnaire in older adults may have an inaccurate measurement of SB levels.