Methods of Assessing Sedentary Behaviour

Increasing amounts of time spent in sedentary behaviour (SB), during occupation or recreation activities, is considered a global health problem. SB has been associated with several non-communicable diseases and all-cause mortality. Thus, it is essential to assess SB through the most accurate and suitable measurement tools. This chapter presents an overview of different methods for assessing SB and highlights the importance of determining the best measurement tool. In choosing an appropriate and accurate method, it is relevant to consider multiple factors, such as population characteristics, context, validity and reliability of measurement tools, and potential research and participant burdens. Subjective measurements, such as self-reported questionnaires, are widely used in epidemiologic studies because they are easy to administer at low cost. However, there is a large variety of questionnaires, which makes it difficult to select a single questionnaire to assess SB. Device-based measurements are more accurate for assessing SB as well as determining bouts and breaks. Both methods present strengths and limitations, and when possible, researchers should use a combination of device-based and subjective methods to improve SB assessment

Physical activity moderates the effect of sedentary time on an older adult's physical independence

Background/objectives: Moderate-to-vigorous physical activity (MVPA) and breaks in sedentary time (BST) have been proposed as viable solutions to improve an older adult's physical independence, whereas sedentary time (ST) has been associated with detrimental effects. We sought to assess the joint effects of ST, BST, and MVPA on the physical independence of older adults and determine whether and to what extent the ST relationship with physical independence is moderated by MVPA and/or BST. Design: Cross-sectional. Setting: Laboratory of Exercise and Health, Faculty of Human Kinetics. Participants: Older adults (≥65 years old) from the national surveillance sys tem in Portugal (n = 821). Measurements: Physical activity and ST were assessed by accelerometry. Physi cal independence was assessed using a 12-item composite physical function (CPF) questionnaire. Multiple linear regression was used to model the outcomes. Results: Higher ST was related to lower CPF score (β = −0.01, p < 0.0001), whereas higher MVPA was related to better CPF score (β = 0.02, p < 0.0001). BST was not related to physical independence after accounting for MVPA and ST (β = 0.03, p = 0.074). MVPA had a moderating effect on the relationship of ST with CPF score (p < 0.0001), where MVPA ≥36.30 min/day ameliorated the significant inverse relationship between ST and CPF. Engaging in ≥107.78 of MVPA resulted in ST having a significant positive relationship with CPF score. No moderation effect was found for BST (p > 0.05). Conclusion: Regardless of the time spent in MVPA and BST, ST was inversely related to CPF. However, MVPA was found to be a moderator of the relationship between ST and physical independence, such that engaging in at least 36 min/day of MVPA may blunt the negative effects of ST. At high levels of MVPA (≥108 min/day), having some ST may actually provide some benefit to an older adult's ability to maintain physical independence

Providing office workers with height-adjustable workstation to reduce and interrupt workplace sitting time: protocol for the Stand Up for Healthy Aging (SUFHA) cluster randomized controlled trial

© The Author(s) 2023. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.Background: Sedentary behavior (SB) has been linked to several negative health outcomes. Therefore, reducing SB or breaking up prolonged periods of SB improves functional fitness, food consumption, job satisfaction, and productivity. Reducing SB can be achieved by introducing a health-enhancing contextual modification promoted by a sit-stand desk in the workplace. The primary goal will be to test the effectiveness of this intervention in reducing and breaking up SB, while improving health outcomes in office-based workers during a 6-month intervention. Methods: A two-arm (1:1), superiority parallel-group cluster RCT will be conducted to evaluate the effectiveness of this intervention in a sample of office-based workers from a university in Portugal. The intervention will consist of a psychoeducation session, motivational prompts, and contextual modification promoted by a sit-stand desk in the workplace for 6 months. The control group will work as usual in their workplace, with no contextual change or prompts during the 6-month intervention. Three assessment points will be conducted in both groups, pre-intervention (baseline), post-intervention, and a 3-month follow-up. The primary outcomes include sedentary and physical activity-related variables, which will be objectively assessed with 24 h monitoring using the ActivPAL for 7 days. The secondary outcomes include (a) biometric indices as body composition, body mass index, waist circumference, and postural inequalities; and (b) psychosocial variables such as overall and work-related fatigue, overall discomfort, life/work satisfaction, quality of life, and eating behavior. Both the primary and secondary outcomes will be assessed at each assessment point. Discussion: This study will lean on the use of a sit-stand workstation for 6 months, prompted by an initial psychoeducational session and ongoing motivational prompts. We will aim to contribute to this topic by providing robust data on alternating sitting and standing postures in the workplace. Trial registration: The trial was prospectively registered, and the details are at: https://doi.org/10.17605/OSF.IO/JHGPW ; Registered 15 November 2022. OSF Preregistration.This study was funded by the ILIND “Fazer+” scientific program (Reference: FAZER+/ILIND/CIDEFES/1/2022).info:eu-repo/semantics/publishedVersio

Relative sit-to-stand power: aging trajectories, functionally relevant cut-off points, and normative data in a large European cohort

Background A validated, standardized, and feasible test to assess muscle power in older adults has recently been re ported: the sit-to-stand (STS) muscle power test. This investigation aimed to assess the relationship between relative STS power and age and to provide normative data, cut-off points, and minimal clinically important differences (MCID) for STS power measures in older women and men. Methods A total of 9320 older adults (6161 women and 3159 men) aged 60–103 years and 586 young and middle-aged adults (318 women and 268 men) aged 20–60 years were included in this cross-sectional study. Relative (normalized to body mass), allometric (normalized to height squared), and specific (normalized to legs muscle mass) muscle power values were assessed by the 30 s STS power test. Body composition was evaluated by dual energy X-ray absorptiometry and bioelectrical impedance analysis, and legs skeletal muscle index (SMI; normalized to height squared) was calculated. Habitual and maximal gait speed, timed up-and-go test, and 6 min walking distance were col lected as physical performance measures, and participants were classified into two groups: well-functioning and mobility-limited older adults. Results Relative STS power was found to decrease between 30–50 years ( 0.05 W·kg 1 ·year 1 ; P > 0.05), 50–80 years ( 0.10 to 0.13 W·kg 1 ·year 1 ; P < 0.001), and above 80 years ( 0.07 to 0.08 W·kg 1 ·year 1 ; P < 0.001). A total of 1129 older women (18%) and 510 older men (16%) presented mobility limitations. Mobility-limited older adults were older and exhibited lower relative, allometric, and specific power; higher body mass index (BMI) and legs SMI (both only in women); and lower legs SMI (only in men) than their well-functioning coun terparts (all P < 0.05). Normative data and cut-off points for relative, allometric, and specific STS power and for BMI and legs SMI were reported. Low relative STS power occurred below 2.1 W·kg 1 in women (area under the curve, AUC, [95% confidence interval, CI] = 0.85 [0.84–0.87]) and below 2.6 W·kg 1 in men (AUC [95% CI] = 0.89 [0.87–0.91]). The age-adjusted odds ratios [95% CI] for mobility limitations in older women and men with low relative STS power were 10.6 [9.0–12.6] and 14.1 [10.9–18.2], respectively. MCID values for relative STS power were 0.33 W·kg 1 in women and 0.42 W·kg 1 in men. Conclusions Relative STS power decreased significantly after the age of 50 years and was negatively and strongly as sociated with mobility limitations. Our study provides normative data, functionally relevant cut-off points, and MCID values for STS power for their use in daily clinical practice

Discrepancies Between Self-reported and Objectively Measured Smartphone Screen Time: Before and During Lockdown

Screen time shows higher health risks compared to other types of sedentary behaviors. A lockdown may simultaneously increase screen time, reduce physical activity (PA), and change time perception. Our goal was to compare self-reported against objectively measured smartphone screen time (SST) in a sample of active and inactive Portuguese adults before and during a social lockdown. This study was a cross-sectional analysis with 211 Portuguese adults (57.8% males), aged 25.2 ± 8.5 years, from two cohorts, one before the social lockdown and the other during the lockdown. SST was self-reported (SR-SST) and objectively measured using a smartphone (OM-SST). PA was self-reported. Linear regressions were performed to determine the association between SR-SST and OM-SST. A Bland and Altman analysis was used to assess agreement. Independent T-tests were performed for comparisons between cohorts and paired sample T-tests for comparisons within each cohort. The cohort assessed during the lockdown showed a higher SST than the cohort assessed before the lockdown (OM-SST; p \u3c 0.001 and SR-SST; p = 0.009). Before the lockdown, there was no difference between SR-SST and OM-SST (p = 0.100). However, during the social lockdown, although the agreement between SR-SST and OM-SST was good (ICC = 0.72), participants systematically underestimated their SST by ~ 71 min/day (p \u3c 0.001), and this underestimation was higher in inactive participants (~ 85 min/day) than in active individuals (~ 49 min/day). The general population needs to be aware of the benefits of limiting screen time, especially during periods of societal modifications, such as a generalized lockdown. There was a tendency to underestimate SST, meaning a lack of awareness of the actual time spent in this potentially deleterious behavior. This underestimation was more pronounced during the lockdown period and for the inactive participants, thus posing a greater health risk. The findings from this investigation entail relevant information for policy makers to delineate strategies for reducing population screen time from a preventive health perspective

Fitness, physical activity, or sedentary patterns? Integrated analysis with obesity surrogates in a large youth sample

© 2020 Wiley Periodicals LLC.Objective: Physical fitness (PF) and physical activity (PA) are inversely associated with body mass index and waist circumference (WC), whereas sedentary time (ST) seems to boost obesity in youth. The aim was to examine the associations of each selected PF test, PA-related exposures, and specific ST patterns with obesity and determine the most relevant ones, in a large sample of a school-aged adolescent. Methods: The sample consisted of 2696 Portuguese youth aged 10 to 18 years. Height, weight, and WC were measured. PA and ST components were measured using accelerometry. PF was evaluated using a battery of tests. Results: The Progressive Aerobic Cardiovascular Endurance Run (PACER) and push-up tests seemed to be the exposures that presented the strongest and more consistent associations with obesity, independent of PA/ST profiles (P < .05). The second exposure of relevance for adolescent obesity level was the breaks in ST with a negative relationship regardless of PA/PF profiles (P < .05). Finally, ST accumulated in periods of <30 minutes, and moderateto-vigorous PA were favorably associated with obesity, independent of ST/PF. Conclusions: Independent of PA and ST, cardiorespiratory fitness (CRF), measured by PACER, was associated with obesity markers. This may be in part due to the dependence of PACER performance on adiposity. Also, limiting prolonged ST and promoting interruptions in this behavior were associated with obesity. These associations suggest that future research should examine other strategies beyond PA promotion for tackling obesity that consider CRF and breaking ST.Duarte Henriques-Neto is supported by a grant from Comité Olímpico de Portugal (doctoral scholarship—COP). Pedro Barracha Júdice is supported by a grant (SFRH/BPD/115977/2016) from the FCT—Fundação para a Ciência e Tecnologia. Miguel Peralta is supported by a grant (SFRH/BD/122219/2016) from FCT - Fundação para a Ciência e Tecnologia. This work was supported by a national grant through the FCT—Fundação para a Ciência e Tecnologia within the unit I&D472 (UID/DTP/00447/2019), Faculty of Human Kinetics of University of Lisbon.info:eu-repo/semantics/publishedVersio

Anthropometry, Physical and Movement Features, and Repeated-sprint Ability in Soccer Players

This study aimed to evaluate the associations of anthropometry, functional movement patterns (FMP) and physical performance characteristics with repeated-sprint ability (RSA) in male youth soccer players. Thirty six athletes (ages 16.6±0.5 years, BMI 22.0±1.3 kg/m2) completed the RSA test and other physical tests including countermovement jump with (CMJA) and without the help of arms (CMJ), 10-m and 20-m straight-line sprints, Yo-Yo Intermittent Recovery Test Level 1 (Yo-Yo), and functional movement screen (FMS). In addition, a battery of anthropometric variables was measured. RSA performance components such as best time (BT), mean time (MT) and sprint decrement were calculated. Results showed that measures of physical performance derived from horizontal plane in 10-m and 20-m sprints, were more strongly associated (p<0.01) with RSA performance than those obtained with CMJ or CMJA (p<0.05). High correlations (p<0.01) were found between MT, BT and Yo-Yo distance (r=-0.79, r=-0.67, respectively), as well as with FMS scores (r=-0.68, r=-0.58, respectively). Anthropometric measures, such as fat mass, upper fat area, thigh fat area, calf muscle area, and endomorphy were associated with RSA components (p<0.05). Predictors for the RSA performance identified in the stepwise multivariate analysis included Yo-Yo distance, time in sprints, FMP, and calf muscle area

Sedentary Patterns, Physical Activity, and Cardiorespiratory Fitness in Association to Glycemic Control in Type 2 Diabetes Patients

Background: Sedentary behavior has been considered an independent risk factor for type-2 diabetes (T2D), with a negative impact on several physiological outcomes, whereas breaks in sedentary time (BST) have been proposed as a viable solution to mitigate some of these effects. However, little is known about the independent associations of sedentary pursuits, physical activity, and cardiorespiratory fitness (CRF) variables with glycemic control. We investigated the independent associations of total sedentary time, BST, moderate-to-vigorous physical activity (MVPA), and CRF with glycemic outcomes in patients with T2D.Methods: Total sedentary time, BST, and MVPA were assessed in 66 participants (29 women) with T2D, using accelerometry. Glucose and insulin were measured during a mixed meal tolerance test, with the respective calculations of HOMA-IR and Matsuda index. Glycated hemoglobin (HbA1c) was also analyzed. CRF was measured in a maximal treadmill test with breath-by-breath gases analysis. Multiple regressions were used for data analysis.Results: Regardless of CRF, total sedentary time was positively associated with HbA1c (β = 0.25, p = 0.044). Adjusting for MVPA, total sedentary time was related to fasting glucose (β = 0.32, p = 0.037). No associations between total sedentary time and the remaining glycemic outcomes, after adjusting for MVPA. BST had favorable associations with HOMA-IR (β = −0.28, p = 0.047) and fasting glucose (β = −0.25, p = 0.046), when adjusted for MVPA, and with HOMA-IR (β = −0.25, p = 0.036), Matsuda index (β = 0.26, p = 0.036), and fasting glucose (β = −0.22, p = 0.038), following adjustment for CRF. When adjusting for total sedentary time, only CRF yielded favorable associations with HOMA-IR (β = −0.29, p = 0.039), fasting glucose (β = −0.32, p = 0.012), and glucose at 120-min (β = −0.26, p = 0.035), and no associations were found for MVPA with none of the metabolic outcomes.Conclusion: The results from this study suggest that sedentary time and patterns are relevant for the glycemic control in patients with T2D. Still, MVPA and CRF counteracted most of the associations for total sedentary time but not for the BST. MVPA was not associated with metabolic outcomes, and CRF lost some of the associations with glycemic indicators when adjusted for total sedentary time. Future interventions aiming to control/improve T2D must consider reducing and breaking up sedentary time as a viable strategy to improve glycemic control

Sedentary Patterns Are Associated with Bone Mineral Density and Physical Function in Older Adults: Cross-Sectional and Prospective Data

Aging causes some unfavorable morphological and functional changes, such as the decline in bone mineral density (BMD) and physical function. Moderate-to-vigorous physical activity (MVPA) and sedentary time seem to be related with these alterations, but the impact of distinct patterns remains unclear. The aim of this study was to cross-sectionally and prospectively assess the association between objectively measured MVPA and sedentary patterns (bouts and breaks) with BMD and physical function in older adults. The study considered 151 Brazilians (aged &ge; 60 years), out of which 68 participants completed 2-year follow-up measurements. MVPA and sedentary patterns were measured by means of accelerometry, BMD&mdash;(total proximal femur and lumbar spine (L1-L4)) by means of dual-energy X-ray absorptiometry (DXA), and physical function&mdash;by means of physical tests. In older women, sedentary bouts &gt;60 min were inversely associated with handgrip strength (&beta; = &minus;2.03, 95% CI: from &minus;3.43 to &minus;0.63). The prospective analyses showed that changes in sedentary bouts (20 to 30 min and &gt;60 min) were inversely associated with changes in the lumbar spine&rsquo;s BMD (&beta; = &minus;0.01, 95% CI: from &minus;0.01 to &minus;0.00 and &beta; = &minus;0.03, 95% CI: from &minus;0.06 to &minus;0.01) and the lumbar spine&rsquo;s T-score (&beta; = &minus;0.06, 95% CI: from &minus;0.10 to &minus;0.01 and &beta; = &minus;0.27, 95% CI: from &minus;0.49 to &minus;0.04), respectively. In older women, sedentary patterns are cross-sectionally associated with handgrip strength and prospectively associated with BMD independent of MVPA

A supervised home-based exercise program for breast cancer survivors' functional performance (Home-Pac): a randomised controlled study.

The goal was to analyze the effects of a home-based exercise intervention, with a supervised component (online group session), and an unsupervised booklet-based component, on the functional performance, quality of life, and physical activity levels of breast cancer survivors ongoing hormonal therap