Active-to-Sedentary Behavior Transitions, Fatigability, and Physical Functioning in Older Adults

Abstract

Background: With aging, daily physical activity (PA) becomes less frequent and more fragmented. Accumulation patterns of daily PAincluding transitions from active-to-sedentary behaviors-may provide important insights into functional status in older, less active populations. Methods: Participants of the Baltimore Longitudinal Study of Aging (n = 680, 50% male, aged 27-94 years) completed a clinical assessment and wore an Actiheart accelerometer. Transitions between active and sedentary states were modeled as a probability (Active-to-Sedentary Transition Probability [ASTP]) defined as the reciprocal of the average PA bout duration. Cross-sectional associations between ASTP and gait speed (m/s), fatigability (rating-of-perceived-exertion [RPE]), 400 m time (seconds), and expanded short physical performance battery score were modeled using linear and logistic regression, adjusted for chronic conditions. Further analyses explored the utility of ASTP over-andabove total daily PA. Results: In continuous models, each 0.10-unit higher ASTP was associated slower gait (β = −0.06 m/s, SE = 0.01), higher fatigability (β = 0.60 RPE, SE = 0.12), slower 400 m time (β = 16.31 s, SE = 2.70), and lower functioning (β = −0.13 expanded short physical performance battery score, SE = 0.03; p < .001). In categorical analyses, those in the highest tertile of ASTP were >2 times more likely to have high fatigability (rating of perceived exertion ≥10), slow 400 m time (>300 seconds) and reduced functional performance (expanded short physical performance battery score < 3.07) than those in the lowest tertile (p < .01). Further analyses demonstrated ASTP provided additional insight into functional outcomes beyond total daily PA. Conclusion: Fragmented daily PA-as measured by ASTP-is strongly linked with measures of health and functional status and may identify those at risk of high fatigability and reduced functional performance over and above traditional PA metrics.

Association of Total Daily Physical Activity and Fragmented Physical Activity With Mortality in Older Adults

“…21,26 The concept of activity fragmentation goes beyond traditional measures of active and sedentary time by using minute-by-minute data to capture the probability of transitioning from an active to a sedentary state in free-living settings. 7,8,11 Yet, the issue of whether deliberative or compensatory alterations in physical activity are associated with functional decline and accelerated mortality risk remains complex. Although current clinical-based functional assessments measure functional limitations, 9,27 ceiling effects limit their ability to assess higher-order physical functioning, such as endurance capacity, fatigability, or walking efficiency.…”

“…With aging and disease, activity becomes less frequent and shorter in duration, or more fragmented, 7 as physiological capacity declines. Fragmented patterns of activity are associated with poorer physical functioning, 7,8 a precursor of disability and frailty, 9,10 and have been detected in cancer survivors with high fatigability and low endurance performance, 11,12 factors consistent with accelerated aging. Thus, activity fragmentation may be a marker of a compromised physiological state and impending decline in health and functional status, making it a potential early target for intervention.…”

Diurnal patterns of sedentary behavior and changes in physical function over time among older women: a prospective cohort study

“…Many investigators have developed new analytic approaches for accelerometer data in an effort to not just measure total accumulation of PA/SB time but to detect patterns in the data. Several studies have investigated patterns based on lengths of uninterrupted intervals ("bouts") and/or degree of fragmentation of PA/SB [15,22,[51][52][53][54][55][56][57]. More relevant to the current investigation, studies have also described variations in the timing of sedentary time and PA time accumulation with respect to hour of the day and/or day of the week, including differences in timing by sociodemographic factors [23,28,[58][59][60][61][62].…”

Effects of Vibrotactile Feedback on Sedentary Behaviors in Adults: A Pilot Randomized Controlled Trial

“…If bouts of sedentary behavior are interrupted for 5 min or longer by standing or walking, greater health and work-productivity benefits can be expected. For that purpose, it is necessary to assess various newly proposed sedentary and activity metrics (e.g., sedentary-to-active transition probabilities) [24] and health and work productivity outcomes. Based on the lessons learned from this study, we plan to refine the intervention program and design another small randomized controlled trial to obtain a robust estimate of effect size; this will be utilized to conduct a larger trial in the future.…”