Using isotemporal substitution to predict the effects of changing physical behaviour on older adults’ cardio-metabolic profiles

Abstract

BackgroundIt has been advocated that older adults should concomitantly spend less time in sedentary behaviour (SB), and engage in sufficient physical activity (PA), to reduce their risk of cardio-metabolic diseases. However, it is not clear what intensity of PA must be done to offset SB engagement.AimModel how cardio-metabolic profiles could change if older adults replaced an hour per day (hr·day-1) of a physical behaviour intensity with 1 hr·day-1 of another physical behaviour of a different intensity.MethodsOlder adults (n = 93, 60–89 years old, 55% female) wore a thigh-mounted triaxial accelerometer for seven consecutive free-living days to estimate mean daily hourly engagement in SB, Standing, Light Intensity PA (LIPA), sporadic moderate to vigorous physical activity (sMVPA, bouts <10 continuous minutes), and 10-minute MVPA (10MVPA, bouts ≥10 continuous minutes. Fasting whole blood concentration of plasma glucose, triglyceride, total cholesterol, and glycated haemoglobin (%), along with serum concentration of lipoprotein lipase (LPL), interleukin-6 (IL-6), and procollagen III N-terminal propeptide (PIIINP) were measured.ResultsIsotemporal Substitution, with covariate adjustment, suggested that: total cholesterol concentration could theoretically decrease when 1 hr·day-1 of SB is replaced with Standing, when 1 hr.day-1 of LIPA is replaced with Standing, and when 1 hr·day-1 of sMVPA is replaced with Standing. Triglyceride concentration theoretically decreased when 1 hr·day-1 of SB, Standing, LIPA, or sMVPA is replaced with 10MVPA. Triglyceride concentration theoretically increases when 1 hr·day-1 of 10MVPA is replaced with SB, Standing, or LIPA. No associations with time reallocation appears to exist for LPL, HbA1c, IL-6, and PIIINP.ConclusionThe type of physical behaviour being replaced could be crucial for total cholesterol maintenance. Engagement in 10MVPA could be necessary to improve triglyceride concentration.

Modelling the Reallocation of Time Spent Sitting into Physical Activity: Isotemporal Substitution vs. Compositional Isotemporal Substitution

“…The associations observed here are similar to previous studies that used ISM and CISM to examine association of reallocating time from one physical behaviour to another on markers of cardiometabolic health [15,19,21,51]. Two previous studies that utilised thighworn accelerometery to assess physical behaviours showed that reallocating time from sitting to movement was favourably associated with waist circumference, triglycerides, and HDL [15,19].…”

“…Reallocating time from sitting to standing was favourably associated with triglycerides and HDL [15]. In older adults, Ryan et al (2019) showed that modelling the reallocation of time in sedentary behaviour to time in physical activity was favourably associated with total cholesterol and triglycerides [21]. In the current study, favourable associations were observed for reallocating time from sitting to standing and stepping for triglycerides, but not for total cholesterol.…”

“…There is a substantial body of epidemiological evidence linking high sedentary behaviour and lack of physical activity (PA) with morbidity [1][2][3][4] and mortality [2,[5][6][7][8]. Recently, there has been an increase in the number of studies that have examined both PA and sedentary behaviour and their impact or associations with health, either by modelling the association of reallocating time from one to another [9][10][11][12][13][14][15][16][17][18][19][20][21][22], or by accounting for the other behaviours as covariates [23][24][25][26].…”

Comparability of Postural and Physical Activity Metrics from Different Accelerometer Brands Worn on the Thigh: Data Harmonization Possibilities

“…The thigh has become a wear location of interest due to its accuracy for estimating the postural component of sedentary behavior (i.e., lying, sitting, and reclining postures) as well as physical activity (Edwardson et al, 2016;Montoye et al, 2016b;Lyden et al, 2017;Sellers et al, 2016). The activPAL device (PAL Technologies Ltd, Glasgow, UK) is specifically designed to be worn on the thigh but more recently other brands of accelerometer, such as ActiGraph, Axivity, and GENEActiv, are being used in this wear location (Daugaard et al, 2018;Hartley et al, 2018;Jørgensen et al, 2019;Ryan et al, 2019). These devices all measure raw acceleration across three axes so there is potential for data harmonization across devices.…”

A Cross-Sectional Examination of Patterns of Sedentary Behavior and Cardiometabolic Risk in Community-Dwelling Adults Aged 55 Years and Older

“…Replacing SB with an equivalent amount of LPA and MVPA was associated with lower odds of metabolic syndrome, decreased clustered cardiometabolic risk, and healthier individual cardiometabolic markers in samples of adults ages 29-82 and 50-64 years [24,25]. In their isotemporal substitution analysis, Ryan et al showed that replacing one hour per day of MVPA with an equivalent amount of SB is associated with higher triglyceride levels in older adults [26]. However, relatively few studies have used isotemporal substitution modeling in the older adult populations [23].…”