Impact of objectively measured sedentary behaviour on changes in insulin resistance and secretion over 3 years in the RISC study: interaction with weight gain

Glycemic control and prescription profiles in internal medicine inpatients: The role of frailty

AIM

This work aims to characterize the clinical profile of individuals with frailty syndrome, diabetes mellitus (DM), and hyperglycemia during hospitalization in regard to glycemic control and treatment regimen.

METHODS

This cross-sectional multicentric study included patients with DM or hyperglycemia at admission. Demographic data, blood glucose values, treatment administered during hospitalization, and treatment indicated at discharge were analyzed. The sample was divided into three groups according to score on a frailty questionnaire. Generalized additive models were used to describe the relationship between either glycemic variability (GV) or minimum capillary blood glucose and hypoglycemia. Models were adjusted for age, comorbidity, and sarcopenia.

RESULTS

A total of 1,137 patients were analyzed. Patients with frailty syndrome had more comorbidity and sarcopenia, worse renal function, and lower albumin and lymphocyte levels. A GV between 21% and 60% was related to a higher probability of hypoglycemia, especially in patients with frailty. Regarding minimum capillary blood glucose, patients with frailty had the highest probability of hypoglycemia. This probability remained significant even in the group with frailty in which, with a reference value of 200 mg/dl, the adjusted odds ratio of a minimum capillary blood glucose of 151 mg/dL was 1.08 (95% confidence interval (1.12-1.05)). Baseline treatments showed a significant predominance of insulin use in the frailest groups.

CONCLUSIONS

Patients with frailty had more sarcopenia and undernourishment. These patients were managed in a similar manner during hospitalization to patients without frailty, despite their higher risk of hypoglycemia according to GV or minimum capillary blood glucose levels.

Role of leisure sedentary behavior on type 2 diabetes and glycemic homeostasis: a Mendelian randomization analysis

Purpose

Utilize Mendelian randomization (MR) to examine the impact of leisure sedentary behavior (LSB) on the prevalence of type 2 diabetes mellitus (T2D) and glycemic homeostasis impairment, as well as to identify potential mediating pathways involved in these associations.

Methods

We chose genetic variants linked to LSB from a large genome-wide association study (GWAS) to use as instrumental variables (IVs). Then, we used a two-sample MR study to investigate the link between LSB and T2D and glycemic homeostasis. Multivariate MR (MVMR) and mediation analysis were also used to look at possible mediating paths.

Results

MR analysis showed a genetical link between leisure TV watching and T2D (OR 1.64, 95% CI 1.39-1.93, P< 0.001) and impaired Glycemic Homeostasis, while leisure computer use seemed to protect against T2D prevalence (OR 0.65, 95% CI 0.50-0.84, P< 0.001). It was found that leisure TV watching increases the risk of T2D through higher BMI (mediation effect 0.23, 95% CI 0.11-0.35, P< 0.001), higher triglycerides (mediation effect 0.07, 95% CI 0.04-0.11, P< 0.001), and less education (mediation effect 0.16, 95% CI 0.08-0.24, P< 0.001). Sensitivity and heterogeneity analyses further substantiated the robustness of these findings. Reverse MR analysis did not yield significant results.

Conclusion

This study shows LSB is linked to a higher rate of T2D and impaired glycemic homeostasis through obesity, lipid metabolism disorders, and reduced educational attainment.

Detrimental effects of physical inactivity on peripheral and brain vasculature in humans: Insights into mechanisms, long-term health consequences and protective strategies

The growing prevalence of physical inactivity in the population highlights the urgent need for a more comprehensive understanding of how sedentary behaviour affects health, the mechanisms involved and what strategies are effective in counteracting its negative effects. Physical inactivity is an independent risk factor for different pathologies including atherosclerosis, hypertension and cardiovascular disease. It is known to progressively lead to reduced life expectancy and quality of life, and it is the fourth leading risk factor for mortality worldwide. Recent evidence indicates that uninterrupted prolonged sitting and short-term inactivity periods impair endothelial function (measured by flow-mediated dilation) and induce arterial structural alterations, predominantly in the lower body vasculature. Similar effects may occur in the cerebral vasculature, with recent evidence showing impairments in cerebral blood flow following prolonged sitting. The precise molecular and physiological mechanisms underlying inactivity-induced vascular dysfunction in humans are yet to be fully established, although evidence to date indicates that it may involve modulation of shear stress, inflammatory and vascular biomarkers. Despite the steady increase in sedentarism in our societies, only a few intervention strategies have been investigated for their efficacy in counteracting the associated vascular impairments. The current review provides a comprehensive overview of the evidence linking acute and short-term physical inactivity to detrimental effects on peripheral, central and cerebral vascular health in humans. We further examine the underlying molecular and physiological mechanisms and attempt to link these to long-term consequences for cardiovascular health. Finally, we summarize and discuss the efficacy of lifestyle interventions in offsetting the negative consequences of physical inactivity.

The association between sedentary behaviour, physical activity and type 2 diabetes markers: A systematic review of mixed analytic approaches

The negative effect of sedentary behaviour on type 2 diabetes markers is established, but the interaction with measures of physical activity is still largely unknown. Previous studies have analysed associations with single-activity models, which ignore the interaction with other behaviours. By including results from various analytical approaches, this review critically summarises the effects of sedentary behaviour on diabetes markers and the benefits of substitutions and compositions of physical activity. Ovid Medline, Embase and Cochrane Library databases were systematically searched. Studies were selected if sedentary behaviour and physical activity were measured by accelerometer in the general population, and if associations were reported with glucose, insulin, HOMA-IR, insulin sensitivity, HbA1c, diabetes incidence, CRP and IL-6. Forty-five studies were included in the review. Conclusive detrimental associations with sedentary behaviour were determined for 2-h insulin (6/12 studies found associations), fasting insulin (15/19 studies), insulin sensitivity (4/6 studies), diabetes (3/4 studies) and IL-6 (2/3 studies). Reallocating sedentary behaviour to light or moderate-to-vigorous activity has a beneficial effect for 2-h glucose (1/1 studies), fasting insulin (3/3 studies), HOMA-IR (1/1 studies) and insulin sensitivity (1/1 studies). Compositional measures of sedentary behaviour were found to affect 2-h glucose (1/1 studies), fasting insulin (2/3 studies), 2-h insulin (1/1 studies), HOMA-IR (2/2 studies) and CRP (1/1 studies). Different analytical methods produced conflicting results for fasting glucose, 2-h glucose, 2-h insulin, insulin sensitivity, HOMA-IR, diabetes, hbA1c, CRP and IL-6. Studies analysing data by quartiles report independent associations between sedentary behaviour and fasting insulin, HOMA-IR and diabetes only for high duration of sedentary time (7-9 hours/day). However, this review could not provide sufficient evidence for a time-specific cut-off of sedentary behaviour for diabetes biomarkers. While substituting sedentary behaviour with moderate-to-vigorous activity brings greater improvements for health, light activity also benefits metabolic health. Future research should elucidate the effects of substituting and combining different activity durations and modalities.

Self-Reported Sedentary Behavior and Metabolic Syndrome among Children Aged 6-14 Years in Beijing, China

(1) Objective: This study aimed to examine the prevalence of metabolic syndrome (MetS) in children aged 6−14 years in Beijing, and to determine whether sedentary behavior is a risk factor. (2) Methods: Using a multistage stratified cluster random sampling method, 3460 students were selected for the Nutrition and Health Surveillance in Schoolchildren of Beijing (NHSSB). Data on children’s sedentary behavior time and MetS indicators were collected using the questionnaires, physical measurements, and laboratory tests. MetS was defined according to the CHN2012 criteria, and logistic regression analysis was used to compare the effects of different sedentary time on MetS and its components. (3) Results: The overall prevalence of MetS among children aged 6−14 in Beijing was 2.4%, and boys, suburban children, and older age were associated with a higher prevalence (χ2 values were 3.947, 9.982, and 27.463, respectively; p < 0.05). In boys, the prevalence rates of abdominal obesity, hyperglycemia, high triglycerides (TG), and low high-density lipoprotein cholesterol (HDL-C) were higher in the high-level sedentary behavior group than those in the low-level sedentary behavior group (p < 0.05); and in girls, the prevalence rates of high TG, low HDL-C, and MetS were higher in the high-level sedentary behavior group than those in the low-level sedentary behavior group (p < 0.05). After adjusting for confounding factors, the multivariate logistic regression results showed that compared with children with low-level sedentary behavior, the risks of abdominal obesity and low HDL-C were higher in boys with high-level sedentary behavior (odds ratio (OR) 1.51, 95% confidence interval (CI) 1.10−2.07, p = 0.011; OR 2.25, 95% CI 1.06−4.76, p = 0.034, respectively); while the risk of abdominal obesity was higher in girls with medium and high-level sedentary behavior (OR 1.52, 95% CI 1.01−2.27, p = 0.043; OR 1.59, 95% CI 1.04−2.43, p = 0.032, respectively). (4) Conclusions: Higher sedentary behavior time was related to the higher risk of MetS components among children aged 6−14 in Beijing. Reducing sedentary behavior may be an important method for preventing metabolic diseases.

Cultural adaptation, translation and validation of the Spanish version of Past-day Adults' Sedentary Time

Background

To better understand sedentary behaviour and favour international comparisons, more evidence from different countries are needed. However, there are a few tools available in Spanish to measure sedentary behaviour. This study aimed to culturally adapt, translate and validate the Past-day Adults’ Sedentary Time (PAST) questionnaire in Chilean adults compared with the ActivPAL.

Method

One hundred one workers wore an ActivPAL for 1 week and were asked to respond to the Spanish version of the PAST twice on different visits at a 7-day interval. The PAST assesses sedentary behaviour in several domains, including working time, during the previous day. Reliability was assessed with the intraclass correlation coefficient (ICC). Correlations and Bland-Altman methods were used to determine accuracy properties of the PAST compared with the ActivPAL.

Results

Seventy-seven participants provided valid data (51.0% male; age = 39.0 ± 12.39 years). The PAST showed moderate reliability (ICC = 0.63). For the total time in sedentary behavior per day, the PAST showed no correlation (r = 0.21, p = 0.07) and a mean bias of 54.9 min/day (LoA 95%: − 484.3, 594.2 min/day) with the ActivPAL. For the total time in SB at work, the PAST showed moderate reliability (ICC = 0.40), weak correlation (r = 0.37, p < 0.002), and mean bias was 33.8 min/day (LoA 95%: − 285.7, 353.3 min/day).

Conclusions

The PAST performed better when estimating sedentary behaviour during working hours compared with the whole day. In this setting, accuracy properties were comparable with other self-report tools.

The role of physical activity in metabolic homeostasis before and after the onset of type 2 diabetes: an IMI DIRECT study

AIMS/HYPOTHESIS

It is well established that physical activity, abdominal ectopic fat and glycaemic regulation are related but the underlying structure of these relationships is unclear. The previously proposed twin-cycle hypothesis (TC) provides a mechanistic basis for impairment in glycaemic control through the interactions of substrate availability, substrate metabolism and abdominal ectopic fat accumulation. Here, we hypothesise that the effect of physical activity in glucose regulation is mediated by the twin-cycle. We aimed to examine this notion in the Innovative Medicines Initiative Diabetes Research on Patient Stratification (IMI DIRECT) Consortium cohorts comprised of participants with normal or impaired glucose regulation (cohort 1: N ≤ 920) or with recently diagnosed type 2 diabetes (cohort 2: N ≤ 435).

METHODS

We defined a structural equation model that describes the TC and fitted this within the IMI DIRECT dataset. A second model, twin-cycle plus physical activity (TC-PA), to assess the extent to which the effects of physical activity in glycaemic regulation are mediated by components in the twin-cycle, was also fitted. Beta cell function, insulin sensitivity and glycaemic control were modelled from frequently sampled 75 g OGTTs (fsOGTTs) and mixed-meal tolerance tests (MMTTs) in participants without and with diabetes, respectively. Abdominal fat distribution was assessed using MRI, and physical activity through wrist-worn triaxial accelerometry. Results are presented as standardised beta coefficients, SE and p values, respectively.

RESULTS

The TC and TC-PA models showed better fit than null models (TC: χ² = 242, p = 0.004 and χ² = 63, p = 0.001 in cohort 1 and 2, respectively; TC-PA: χ² = 180, p = 0.041 and χ² = 60, p = 0.008 in cohort 1 and 2, respectively). The association of physical activity with glycaemic control was primarily mediated by variables in the liver fat cycle.

CONCLUSIONS/INTERPRETATION

These analyses partially support the mechanisms proposed in the twin-cycle model and highlight mechanistic pathways through which insulin sensitivity and liver fat mediate the association between physical activity and glycaemic control.

A single bout of resistance exercise improves postprandial lipid metabolism in overweight/obese men with prediabetes

AIMS/HYPOTHESIS

Prediabetes is associated with postprandial hypertriacylglycerolaemia. Resistance exercise acutely lowers postprandial plasma triacylglycerol (TG); however, the changes in lipid metabolism that mediate this reduction are poorly understood. The aim of this study was to identify the constitutive metabolic mechanisms underlying the changes in postprandial lipid metabolism after resistance exercise in obese men with prediabetes.

METHODS

We evaluated the effect of a single bout of whole-body resistance exercise (seven exercises, three sets, 10-12 repetitions at 80% of one-repetition maximum) on postprandial lipid metabolism in ten middle-aged (50 ± 9 years), overweight/obese (BMI: 33 ± 3 kg/m²), sedentary men with prediabetes (HbA_1c >38 but <48 mmol/mol [>5.7% but <6.5%]), or fasting plasma glucose >5.6 mmol/l but <7.0 mmol/l or 2 h OGTT glucose >7.8 mmol/l but <11.1 mmol/l). We used a randomised, crossover design with a triple-tracer mixed meal test (ingested [(¹³C₄)₃]tripalmitin, i.v. [U-¹³C₁₆]palmitate and [²H₅]glycerol) to evaluate chylomicron-TG and total triacylglycerol-rich lipoprotein (TRL)-TG kinetics. We used adipose tissue and skeletal muscle biopsies to evaluate the expression of genes regulating lipolysis and lipid oxidation, skeletal muscle respirometry to evaluate oxidative capacity, and indirect calorimetry to assess whole-body lipid oxidation.

RESULTS

The single bout of resistance exercise reduced the lipaemic response to a mixed meal in obese men with prediabetes without changing chylomicron-TG or TRL-TG fractional clearance rates. However, resistance exercise reduced endogenous and meal-derived fatty acid incorporation into chylomicron-TG and TRL-TG. Resistance exercise also increased whole-body lipid oxidation, skeletal muscle mitochondrial respiration, oxidative gene expression in skeletal muscle, and the expression of key lipolysis genes in adipose tissue.

CONCLUSIONS/INTERPRETATION

A single bout of resistance exercise improves postprandial lipid metabolism in obese men with prediabetes, which may mitigate the risk for cardiovascular disease and type 2 diabetes.

The effects of cigarette smoking on the associations between sitting time and all-cause mortality: a meta-analysis

BACKGROUND

Sedentary behavior is recognized as an independent risk factor for mortality, but it remains unclear whether cigarette smoking will aggravate the detrimental effects of prolonged sitting on mortality. This study examined the impact of cigarette smoking on the relationship between sitting time and all-cause mortality in adults.

METHODS

Electronic database searches were conducted in PubMed, Web of Science, and the EMBASE up to 1 June 2017. Prospective studies that reported sitting time, percent of current smokers, and all-cause mortality were included. Data were extracted independently by two authors.

RESULTS

Ten prospective studies met the inclusion criteria. These studies included 850990 adults who were followed up for 2-15.7 years, during which 64 781 died (7.6%). Generally, during follow-up sitting time showed a dose-response relationship with all-cause mortality, with each 1 h increment of sitting time per day accounting for hazard ratio (HR) of mortality 1.02 (95%CI, 1.02-1.03). The relationship remained significant when stratified by the quartiles of smoking populations (≤8.4%, 8.5%-12.6%, 12.7%-27.9%, and ≥28.0%), and the risk of sitting time-related mortality increased parallel to the increment of the percent of smoking populations, with HRs 1.02 (95%CI, 1.02-1.03), 1.03 (95%CI, 1.02-1.03), 1.04 (95%CI, 1.03-1.04) and 1.06 (95%CI, 1.06-1.06), respectively. The associations between the risk of prolonged sitting-related mortality and the percent of smoking populations were linear (P = 0.032).

CONCLUSIONS

Cigarette smoking significantly aggravated the detrimental effects of sitting time on all-cause mortality. Our findings provided further evidence on the harmful effects of smoking combing prolonged sitting on adult health.

[Antioxidant and anti-inflammatory modulation of exercise during aging]

Aging is characterised by a gradual loss of the functional reserve. This, along with the fostering of sedentary habits and the increase in risk factors, causes a deterioration of antioxidant defences and an increase of the circulatory levels of inflammatory and oxidative markers, boosting a low-rate chronic inflammation, defined as inflamm-aging. This phenomenon is present in the aetiopathology of chronic diseases, as well as in cognitive deterioration cases associated with aging. The objective of this review is to describe the modulation of antioxidant and anti-inflammatory effects of physical exercise of moderate intensity and volume in the elderly. Evidence of its effectiveness as a non-pharmacological resource is presented, which decreases some deleterious effects of aging. This is mainly due to its neuroprotective action, the increase in circulating anti-inflammatory markers, and the improvement of antioxidant defence derived from its practice.

The cross-sectional associations between objectively measured sedentary time and cardiometabolic health markers in adults - a systematic review with meta-analysis component

Sedentary time is viewed as an independent risk factor for adverse cardiometabolic health (CMH). No systematic review and meta-analysis on the cross-sectional associations between objectively measured sedentary time and CMH markers has been conducted. PubMed, Scopus and Web of Science Core Collection were searched for papers that examined the cross-sectional association between objectively measured sedentary time and CMH markers in adults. Forty-six papers met the inclusion criteria. The included papers had a combined sample size of 70,576 and an age range of 18-87 years. To examine the effect of increased levels of sedentary time on CMH markers, data on effect sizes and moderators were extracted, where possible. By pooling the unadjusted data from the included papers, increased sedentary time was shown to have a significant detrimental association with fasting glucose (Δ = 0.12, 95% confidence interval [CI]: 0.02, 0.23), fasting insulin (Δ = 0.19, 95% CI: 0.06, 0.32), triglycerides (Δ = 0.25, 95% CI: 0.14, 0.37), high-density lipoprotein cholesterol (Δ = -0.20, 95% CI: -0.28, -0.13) and waist circumference (Δ = 0.25, 95% CI: 0.15, 0.35). How sedentary time was quantified and the device used to measure sedentary time significantly influence the size of the effect reported. Future interventions focused on both decreasing sedentary time and increasing physical activity may be the most effective strategy to improve CMH.

Replacement of Sedentary Time with Physical Activity: Effect on Lipoproteins

PURPOSE

Limited data on the relationship between physical activity and lipoprotein particle profiles exist. Our objective was to investigate associations between objectively measured physical activity and lipoprotein particle size and number, and specifically whether substituting daily sedentary behavior with light activity or moderate-to-vigorous physical activity (MVPA) is associated with beneficial alterations to the lipoprotein profile among adults and those at increased cardiometabolic risk (obese and insulin-resistant subjects).

METHODS

Sedentary behavior and physical activity intensity and duration were measured for 7 consecutive days using the GENEActiv accelerometer in a cross-sectional adult cohort (n = 396; mean age, 59.6 ± 5.5 yr). Lipoprotein particle size and subclass concentrations were determined using nuclear magnetic resonance spectroscopy. Isotemporal substitution regression modeling quantified the associations between replacing 30 min·d of sedentary behavior with equal amounts of light activity and MVPA on lipoprotein profiles.

RESULTS

Daily duration of MVPA was inversely associated with large VLDL particles and lipoprotein insulin resistance scores (P < 0.05, after adjustment for sedentary time and other confounding factors). Reallocating 30 min of sedentary time with MVPA, but not light activity, was associated with less large VLDL particles resulting in more favorable average VLDL particle size and improved lipoprotein insulin resistance score (P < 0.05). Analysis of high-cardiometabolic-risk groups revealed similar beneficial alterations to VLDL profiles (P < 0.05) with substitution of sedentary time for MVPA among the insulin-resistant (homeostasis model assessment for insulin resistance ≥75th percentile) but not the obese (body mass index ≥30 kg·m) individuals.

CONCLUSIONS

Daily MVPA duration and theoretical replacement of sedentary time with MVPA, but not light activity, were associated with less atherogenic VLDL profiles, particularly among the insulin-resistant individuals. These findings, which require further investigation, highlight the need to develop physical activity interventions aimed at improving atherogenic dyslipidemia and lowering cardiometabolic risk.

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.

Leisure-time physical activity, sedentary behaviors, sleep, and cardiometabolic risk factors at baseline in the PREDIMED-PLUS intervention trial: A cross-sectional analysis

Limited data exists on the interrelationships between physical activity (PA), sedentary behaviors and sleep concerning cardiometabolic risk factors in aged adults at high cardiovascular disease risk. Our aim was to examine independent and joint associations between time spent in leisure-time PA, sedentary behaviors and sleep on the prevalence of obesity, type 2 diabetes (T2D) and components of the metabolic syndrome (MetS) in Mediterranean individuals at high cardiovascular risk. Cross-sectional analyses were performed on baseline data from 5776 Spanish adults (aged 55-75y in men; 60-75y in women) with overweight/obesity and MetS, from October 2013 to October 2016, in the PREDIMED-PLUS trial. Employing multivariable-adjusted Cox regression with robust variance and constant time (given the cross-sectional design), higher prevalence of obesity, T2D and abdominal obesity as component of the MetS were associated with greater time in TV-viewing (Relative Risk, RR: 1.02, 95%CI: 1.01, 1.03; RR:1.04, 95%CI: 1.02, 1.06 and RR: 1.01 95%CI: 1.00, 1.02; respectively, all P < .01). Conversely, greater time in moderate-vigorous PA (MVPA) was associated with lower prevalence of obesity, T2D, abdominal obesity and low HDL-cholesterol (RR: 0.95, 95%CI: 0.93, 0.97; RR: 0.94, 95%CI: 0.89, 0.99; RR: 0.97, 95%CI: 0.96, 0.98; and RR: 0.95, 95%CI: 0.91, 0.99, respectively, all P < .05). For these outcomes, theoretically substituting 1-h/day of MVPA for 1-h/day TV-viewing was also significantly associated with lower prevalence (RR 0.91 to 0.97, all P < .05). Similar lower RR in these outcomes was observed when substituting 1-h/day of MVPA for 1-h/day of sleeping. Longer time watching TV and not meeting MVPA recommendations were jointly associated with higher RR of the prevalence of obesity and T2D. We concluded that, in senior individuals at high cardiovascular risk, greater time spent on MVPA and fewer on sedentary behaviors was inversely associated with prevalence of obesity, T2D, and some of the components of MetS.

Associations of total amount and patterns of sedentary behaviour with type 2 diabetes and the metabolic syndrome: The Maastricht Study

AIMS/HYPOTHESIS

The study investigated cross-sectional associations of total amount and patterns of sedentary behaviour with glucose metabolism status and the metabolic syndrome.

METHODS

We included 2,497 participants (mean age 60.0 ± 8.1 years, 52% men) from The Maastricht Study who were asked to wear an activPAL accelerometer 24 h/day for 8 consecutive days. We calculated the daily amount of sedentary time, daily number of sedentary breaks and prolonged sedentary bouts (≥30 min), and the average duration of the sedentary bouts. To determine glucose metabolism status, participants underwent an oral glucose tolerance test. Associations of sedentary behaviour variables with glucose metabolism status and the metabolic syndrome were examined using multinomial logistic regression analyses.

RESULTS

Overall, 1,395 (55.9%) participants had normal glucose metabolism, 388 (15.5%) had impaired glucose metabolism and 714 (28.6%) had type 2 diabetes. The odds ratio per additional hour of sedentary time was 1.22 (95% CI 1.13, 1.32) for type 2 diabetes and 1.39 (1.27, 1.53) for the metabolic syndrome. No significant or only weak associations were seen for the number of sedentary breaks, number of prolonged sedentary bouts or average bout duration with either glucose metabolism status or the metabolic syndrome.

CONCLUSIONS/INTERPRETATION

An extra hour of sedentary time was associated with a 22% increased odds for type 2 diabetes and a 39% increased odds for the metabolic syndrome. The pattern in which sedentary time was accumulated was weakly associated with the presence of the metabolic syndrome. These results suggest that sedentary behaviour may play a significant role in the development and prevention of type 2 diabetes, although longitudinal studies are needed to confirm our findings.

Prospective associations between sedentary time, physical activity, fitness and cardiometabolic risk factors in people with type 2 diabetes

AIMS/HYPOTHESIS

The aim of this study was to examine the prospective associations between objectively measured physical activity energy expenditure (PAEE), sedentary time, moderate-to-vigorous-intensity physical activity (MVPA), cardiorespiratory fitness (CRF) and cardiometabolic risk factors over 4 years in individuals with recently diagnosed diabetes.

METHODS

Among 308 adults (mean age 61.0 [SD 7.2] years; 34% female) with type 2 diabetes from the Anglo-Danish-Dutch Study of Intensive Treatment in People with Screen Detected Diabetes in Primary Care (ADDITION)-Plus study, we measured physical activity using individually calibrated combined heart rate and movement sensing. Multivariable linear regression models were constructed to examine the associations between baseline PAEE, sedentary time, MVPA, CRF and cardiometabolic risk factors and clustered cardiometabolic risk (CCMR) at follow-up, and change in these exposures and change in CCMR and its components over 4 years of follow-up.

RESULTS

Individuals who increased their PAEE between baseline and follow-up had a greater reduction in waist circumference (-2.84 cm, 95% CI -4.84, -0.85) and CCMR (-0.17, 95% CI -0.29, -0.04) compared with those who decreased their PAEE. Compared with individuals who decreased their sedentary time, those who increased their sedentary time had a greater increase in waist circumference (3.20 cm, 95% CI 0.84, 5.56). Increases in MVPA were associated with reductions in systolic blood pressure (-6.30 mmHg, 95% CI -11.58, -1.03), while increases in CRF were associated with reductions in CCMR (-0.23, 95% CI -0.40,-0.05) and waist circumference (-3.79 cm, 95% CI -6.62, -0.96). Baseline measures were generally not predictive of cardiometabolic risk at follow-up.

CONCLUSIONS/INTERPRETATION

Encouraging people with recently diagnosed diabetes to increase their physical activity and decrease their sedentary time may have beneficial effects on their waist circumference, blood pressure and CCMR.

Association Between Daily Time Spent in Sedentary Behavior and Duration of Hyperglycemia in Type 2 Diabetes

Exercise and sedentary behavior have different physiologic effects, which have yet to be fully explained. Time spent in sedentary behavior has been associated with glucose intolerance in adults at risk for type 2 diabetes, but these data have come largely from cross-sectional studies that have not explored this relationship in adults with diabetes. The specific aim of this study was to examine the relationship between time spent in sedentary behavior and glucose levels in adults diagnosed with type 2 diabetes over 3-5 days.

METHODS

Using continuous and concurrent data gathered from wrist accelerometry and a Continuous Glucose-Monitoring Sensor (CGMS), we conducted a longitudinal, descriptive study involving 86 patients with type 2 diabetes.

RESULTS

More time spent in sedentary behavior was predictive of significant increases in time spent in hyperglycemia (B = 0.12, p < .05).

CONCLUSIONS

These findings highlight the relationship between time spent sedentary and time spent in hyperglycemia, as identified through our use of objective, continuous data collection methods for both sedentary behavior and glucose levels across multiple days (Actiwatch, CGMS). For patients with type 2 diabetes, these findings emphasize the need for the development of individualized interventions aimed at decreasing the amount of time spent in hyperglycemia by reducing sedentary time.

Accelerometer-measured sedentary time and cardiometabolic biomarkers: A systematic review

OBJECTIVE

We conducted a systematic review to investigate the cross-sectional and prospective associations of accelerometer-measured total sedentary time and breaks in sedentary time with individual cardiometabolic biomarkers in adults ≥18years of age.

METHODS

Ovid Medline, Embase, Web of Science and the Cochrane Library were searched for studies meeting the inclusion criteria. Due to inconsistencies in the measurement and analysis of sedentary time, data was synthesised and presented narratively rather than as a meta-analysis.

RESULTS

Twenty-nine studies were included in the review; twenty-eight reported on total sedentary time and six on breaks in sedentary time. There was consistent evidence from cross-sectional data of an unfavourable association between total sedentary time and insulin sensitivity. There was also some evidence that total sedentary time was unfavourably associated with fasting insulin, insulin resistance and triglycerides. Furthermore, there was some evidence from cross-sectional data of a favourable association between breaks in sedentary time and triglycerides.

CONCLUSION

Total sedentary time was consistently shown to be associated with poorer insulin sensitivity, even after adjusting for time spent in physical activity. This finding supports the proposed association between sedentary time and the development of Type 2 diabetes and reinforces the need to identify interventions to reduce time spent sedentary.

Sedentary Behavior as a Risk Factor for Physical Frailty Independent of Moderate Activity: Results From the Osteoarthritis Initiative

OBJECTIVES

This prospective longitudinal study investigated the association between baseline objectively measured sedentary time and 2-year onset of physical frailty.

METHODS

We studied 1333 Osteoarthritis Initiative participants 55 to 83 years of age who were at risk for physical frailty, as assessed via low gait speed (< 0.6 m per second) or inability to perform a single chair stand. Baseline sedentary time was assessed through accelerometer monitoring. Hazard ratios (HRs) for physical frailty onset were estimated with discrete survival methods that controlled for moderate physical activity, sociodemographic characteristics, baseline gait and chair stand functioning, and health factors.

RESULTS

The incidence of physical frailty in this high-risk group was 20.7 per 1000 person-years. Greater baseline sedentary time (adjusted HR = 1.36 per sedentary hour; 95% confidence interval [CI] = 1.02, 1.79) was significantly related to incident physical frailty after control for time spent in moderate-intensity activities and other covariates.

CONCLUSIONS

Our prospective data demonstrated a strong relationship between daily sedentary time and development of physical frailty distinct from insufficient moderate activity. Interventions that promote reductions in sedentary behaviors in addition to increases in physical activity may help decrease physical frailty onset.

Validation of PIN 3 physical activity survey in low-income overweight and obese young mothers

Background

Existing physical activity surveys have not been validated for use with low-income overweight and obese young mothers. This study aimed to validate the Pregnancy Infection and Nutrition 3 (PIN3) physical activity survey and to explore whether its validity varied by race/ethnicity and body mass index (BMI) category when including or excluding child and adult care activities in the target population.

Methods

Participants were recruited from the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) and were asked to fill out the PIN3 survey and wear an Actigraph accelerometer. Validity was assessed (N = 42) using Spearman correlation coefficient.

Results

Regardless of inclusion or exclusion of child and adult care activity, the PIN3 survey showed evidence of validity for moderate (correlation coefficients 0.33 [p = 0.03]; 0.40 [p = 0.08]) but not vigorous (−0.01 [p = 0.91]; −0.06 [p = 0.69]) physical activity. The mean minutes per week spent in moderate, vigorous and moderate-vigorous physical activity measured by the PIN3 were substantially higher than when measured by accelerometer, for example, 588 (PIN3) versus 148 (accelerometer) minutes per week. Also, correlations between self-reported and objective monitored activity varied substantially by race/ethnicity and BMI category, for example, 0.29 (p = 0.18) for overweight women versus 0.57 (p = 0.007) for obese women; 0.27 (p = 0.20) for African American versus 0.66 (p = 0.001) for white.

Conclusions

The PIN3 survey may be adequate for many applications where quick and practical assessments are needed for moderate physical activity data in low-income overweight and obese young mothers. The substantial differences in mean minutes per week between the PIN3 and accelerometer may be due to over-reported physical activity by the study participants.

Trial registration

Clinical Trials Number: NCT01839708

Increasing objectively measured sedentary time increases clustered cardiometabolic risk: a 6 year analysis of the ProActive study

AIMS/HYPOTHESIS

We aimed to quantify the associations between change in objectively measured sedentary and moderate-to-vigorous physical activity (MVPA) times and self-reported television viewing over 6 years and change in a clustered cardiometabolic risk score (CCMR), including and excluding waist circumference (CCMR without adiposity component, CCMR no adip ), and its individual components, among the adult children of people with type 2 diabetes.

METHODS

In 171 adults (mean ± SD age 42.52 ± 6.30 years; 46% men) with a parental history of diabetes (ProActive UK), physical activity accelerometer measures and self-reported television viewing were assessed at baseline and a mean ± SD of 6.27 ± 0.46 years later. Associations between change in sedentary time, MVPA time and television viewing and cardiometabolic risk and mediation by adiposity change were examined by multiple linear regression and the product of coefficients method, respectively.

RESULTS

Greater increases in sedentary time (h/day) were associated with larger increases in clustered cardiometabolic risk (CCMR: 0.08 [95% CI 0.01, 0.15]; CCMR no adip : 0.08 [0.01, 0.16]) and triacylglycerol (0.15 [0.01, 0.29]), independent of baseline sedentary and MVPA times, change in MVPA time and other confounders. No evidence was found for mediation by change in waist circumference and BMI for the associations with CCMR no adip and triacylglycerol. Greater increases in MVPA time (h/day) were associated with larger decreases in waist circumference (-3.86 [-7.58, -0.14]), independently of baseline MVPA and sedentary times, change in sedentary time and other confounders. Television viewing was not independently associated with any of the cardiometabolic outcomes.

CONCLUSIONS/INTERPRETATION

Increasing sedentary time is independently related to increasing clustered cardiometabolic risk and triacylglycerol in adults at high risk of developing diabetes. Strategies to prevent diabetes might target reducing sedentary time. Trial registration ISRCTN61323766.