Sedentary behavior as a mediator of type 2 diabetes

Sedentary behavior, exercise and COVID-19: immune and metabolic implications in obesity and its comorbidities

Many reports showed a dramatic decrease in the levels of physical activity during the current pandemic of SARS-CoV-2. This has substantial immune and metabolic implications, especially in those at risk or with metabolic diseases including individuals with obesity and Type 2 diabetes. In this study we discussed the route from physical inactivity to immune and metabolic aberrancies; focusing on how insulin resistance could represent an adaptive mechanism to the low physical activity levels and on how such an adaptive mechanism could shift to a pathognomonic feature of metabolic diseases, creating a vicious circle of immune and metabolic aberrancies. We provide a theoretical framework to the severe immunopathology of COVID-19 in patients with metabolic diseases. We finally discuss the idea of exercise as a potential adjuvant against COVID-19 and emphasize how even interrupting prolonged periods of sitting with short time breaks of very light activity could be a feasible strategy to limit the deleterious effects of the outbreak.

The Predictive Performance of Objective Measures of Physical Activity Derived From Accelerometry Data for 5-Year All-Cause Mortality in Older Adults: National Health and Nutritional Examination Survey 2003-2006

BACKGROUND

Declining physical activity (PA) is a hallmark of aging. Wearable technology provides reliable measures of the frequency, duration, intensity, and timing of PA. Accelerometry-derived measures of PA are compared with established predictors of 5-year all-cause mortality in older adults in terms of individual, relative, and combined predictive performance.

METHODS

Participants aged between 50 and 85 years from the 2003-2006 National Health and Nutritional Examination Survey (NHANES, n = 2,978) wore a hip-worn accelerometer in the free-living environment for up to 7 days. A total of 33 predictors of 5-year all-cause mortality (number of events = 297), including 20 measures of objective PA, were compared using univariate and multivariate logistic regression.

RESULTS

In univariate logistic regression, the total activity count was the best predictor of 5-year mortality (Area under the Curve (AUC) = 0.771) followed by age (AUC = 0.758). Overall, 9 of the top 10 predictors were objective PA measures (AUC from 0.771 to 0.692). In multivariate regression, the 10-fold cross-validated AUC was 0.798 for the model without objective PA variables (9 predictors) and 0.838 for the forward selection model with objective PA variables (13 predictors). The Net Reclassification Index was substantially improved by adding objective PA variables (p < .001).

CONCLUSIONS

Objective accelerometry-derived PA measures outperform traditional predictors of 5-year mortality, including age. This highlights the importance of wearable technology for providing reproducible, unbiased, and prognostic biomarkers of health.

Investigation of geographic disparities of pre-diabetes and diabetes in Florida

BACKGROUND

Diabetes is a leading cause of death and disability in the United States, and its precursor, pre-diabetes, is estimated to occur in one-third of American adults. Understanding the geographic disparities in the distribution of these conditions and identifying high-prevalence areas is critical to guiding control and prevention programs. Therefore, the objective of this study was to investigate clusters of pre-diabetes and diabetes risk in Florida and identify significant predictors of the conditions.

METHODS

Data from the 2013 Behavioral Risk Factor Surveillance System were obtained from the Florida Department of Health. Spatial scan statistics were used to identify and locate significant high-prevalence local clusters. The county prevalence proportions of pre-diabetes and diabetes and the identified significant clusters were displayed in maps. Logistic regression was used to identify significant predictors of the two conditions for individuals living within and outside high-prevalence clusters.

RESULTS

The study included a total of 34,186 respondents. The overall prevalence of pre-diabetes and diabetes were 8.2 and 11.5%, respectively. Three significant (p < 0.05) local, high-prevalence spatial clusters were detected for pre-diabetes, while five were detected for diabetes. The counties within the high-prevalence clusters had prevalence ratios ranging from 1.29 to 1.85. There were differences in the predictors of the conditions based on whether respondents lived within or outside high-prevalence clusters. Predictors of both pre-diabetes and diabetes regardless of region or place of residence were obesity/overweight, hypertension, and hypercholesterolemia. Income and physical activity level were significant predictors of diabetes but not pre-diabetes. Arthritis, sex, and marital status were significant predictors of diabetes only among residents of high-prevalence clusters, while educational attainment and smoking were significant predictors of diabetes only among residents of non-cluster counties.

CONCLUSIONS

Geographic disparities of pre-diabetes and diabetes exist in Florida. Information from this study is useful for guiding resource allocation and targeting of intervention programs focusing on identified modifiable predictors of pre-diabetes and diabetes so as to reduce health disparities and improve the health of all Floridians.

Physical Activity, Screen Time, and Emotional Well-Being during the 2019 Novel Coronavirus Outbreak in China

We aimed to evaluate the effects of the COVID-19 lock down on lifestyle in China during the initial stage of the pandemic. A questionnaire was distributed to Chinese adults living in 31 provinces of China via the internet using a snowball sampling strategy. Information on 7-day physical activity recall, screen time, and emotional state were collected between January 24 and February 2, 2020. ANOVA, χ² test, and Spearman’s correlation coefficients were used for statistical analysis. 12,107 participants aged 18–80 years were included. During the initial phase of the COVID-19 outbreak, nearly 60% of Chinese adults had inadequate physical activity (95% CI 56.6%–58.3%), which was more than twice the global prevalence (27.5%, 25.0%–32.2%). Their mean screen time was more than 4 hours per day while staying at home (261.3 ± 189.8 min per day), and the longest screen time was found in young adults (305.6 ± 217.5 min per day). We found a positive and significant correlation between provincial proportions of confirmed COVID-19 cases and negative affect scores (r = 0.501, p = 0.004). Individuals with vigorous physical activity appeared to have a better emotional state and less screen time than those with light physical activity. During this nationwide lockdown, more than half of Chinese adults temporarily adopted a sedentary lifestyle with insufficient physical activity, more screen time, and poor emotional state, which may carry considerable health risks. Promotion of home-based self-exercise can potentially help improve health and wellness.

The interactions of diet-induced obesity and organophosphate flame retardant exposure on energy homeostasis in adult male and female mice

Previously, sex-dependent alterations in energy homeostasis were reported in adult mice fed a standard chow attributed to exposure to a mixture of organophosphate flame retardants (OPFRs) via estrogen receptors (ERα). In this study, adult male and female mice (C57BL/6J; Taconic) were treated with the same mixture of OPFRs (1 mg/kg each of tricresyl phosphate (TCP), triphenyl phosphate (TPP), and tris(1-3-dichloro-2propyl)phosphate (TDCPP)) for 7 weeks on a low-fat diet (LFD, 10% kcal fat) or a high fat (HFD, 45% kcal fat) in a diet-induced obesity model. Consistent with our previous observations, OPFRs altered weight gain in males, differentially with diet, while females remained unaffected. OPFR treatment also revealed sex-dependent perturbations in metabolic activity. During the night (approximately 0100-0400 hr), males exhibited elevated activity and oxygen consumption, while in females these parameters were decreased, irrespective of diet. OPFR disrupted feeding behavior and abolished diurnal water intake patterns in females while increasing nighttime fluid consumption in males. Despite no marked effect of OPFRs on glucose or insulin tolerance, OPFR treatment altered circulating insulin and leptin in females and ghrelin in males. Data indicate that adult OPFR exposure might influence, and perhaps exacerbate, the effects of diet-induced obesity in adult mice by altering activity, ingestive behavior, and metabolism.

Physical activity attenuates cardiovascular risk and mortality in men and women with and without the metabolic syndrome - a 20-year follow-up of a population-based cohort of 60-year-olds

AIMS

The purpose of this study was to analyse the association of leisure-time physical activity of different intensities at baseline, and cardiovascular disease incidence, cardiovascular disease mortality and all-cause mortality in a population-based sample of 60-year-old men and women with and without established metabolic syndrome, for more than 20 years of follow-up. A secondary aim was to study which cardiometabolic factors may mediate the association between physical activity and long-term outcomes.

METHODS

A total of 3693 participants (53% women) underwent physical examination and laboratory tests, completed an extensive questionnaire at baseline 1997-1999 and were followed until their death or until 31 December 2017. First-time cardiovascular disease events and death from any cause were ascertained through regular examinations of national registers.

RESULTS

Metabolic syndrome prevalence was 23.0%. In metabolic syndrome participants, light physical activity attenuated cardiovascular disease incidence (hazard ratio = 0.71; 95% confidence interval 0.50-1.00) compared to sedentary (reference) after multi-adjustment. Moderate/high physical activity was inversely associated with both cardiovascular disease and all-cause mortality, but became non-significant after multi-adjustment. Sedentary non-metabolic syndrome participants had lower cardiovascular disease incidence (0.47; 0.31-0.72) but not significantly different cardiovascular disease (0.61; 0.31-1.19) and all-cause mortality (0.92; 0.64-1.34) compared to sedentary metabolic syndrome participants. Both light and moderate/high physical activity were inversely associated with cardiovascular disease and all-cause mortality in non-metabolic syndrome participants (p<0.05). There were significant variations in several central cardiometabolic risk factors with physical activity level in non-metabolic syndrome participants. Fibrinogen mediated the protective effects of physical activity in non-metabolic syndrome participants.

CONCLUSION

Physical activity of different intensities attenuated cardiovascular risk and mortality in 60-year old men and women with metabolic syndrome during a 20-year follow-up.

Postprandial skeletal muscle metabolism following a high-fat diet in sedentary and endurance-trained males

Our objective was to determine the influence of a high-fat diet (HFD) on fasting and postprandial skeletal muscle substrate metabolism in endurance-trained (ET) compared with sedentary (SED) humans. SED (n = 17) and ET (n = 7) males were control-fed a 10-day moderate-fat diet followed by a 5-day isocaloric HFD (55% fat, 30% carbohydrate). Skeletal muscle biopsies were taken in the fasted condition and 4 h after a high-fat meal (820 kcals; 63% fat and 25% carbohydrate). Palmitate-induced suppression of pyruvate oxidation, an indication of substrate preference, and oxidation of fat and glucose were measured in homogenized skeletal muscle in fasted and fed states. Postprandial responses were calculated as percent changes from fasting to fed states. Postprandial suppression of pyruvate oxidation was maintained after the HFD in ET, but not SED skeletal muscle, suggesting greater adaptability to dietary intake changes in the former. Fasting total fat oxidation increased due to the HFD in ET skeletal muscle (P = 0.006), which was driven by incomplete fat oxidation (P = 0.008). Fasting fat oxidation remained unchanged in skeletal muscle of SED individuals. Yet, postprandial fat oxidation was similar between groups. Fasting glucose oxidation was elevated after the HFD in ET (P = 0.036), but not SED, skeletal muscle. Postprandial glucose oxidation was reduced due to the HFD in SED (P = 0.002), but not ET, skeletal muscle. These findings provide insight into differing substrate metabolism responses between SED and ET individuals and highlight the role that the prevailing diet may play in modulating fasting and postprandial metabolic responses in skeletal muscle.NEW & NOTEWORTHY The relationship between high dietary fat intake and physical activity level and their combined effect on skeletal muscle substrate metabolism remains unclear. We assessed the influence of the prevailing diet in modulating substrate oxidation in skeletal muscle of endurance-trained compared with sedentary humans during a high-fat challenge meal. Collectively, our findings demonstrate the adaptability of skeletal muscle in endurance-trained individuals to high dietary fat intake.

Hours lying down per day, as a proxy for sedentary behaviour and risk of diabetes in young and middle-aged adults in Norway: an 11-year follow-up of the HUNT study

OBJECTIVE

We aimed to examine relationship between hours lying down per day, as a proxy for sedentary behaviour and risk of diabetes in young and middle-aged adults, and to assess if leisure-time physical activity and body mass index (BMI) modified this relationship.

DESIGN

A population-based prospective cohort study.

SETTING

Nord-Trøndelag, Norway.

PARTICIPANTS

The cohort included 17 058 diabetes-free adults, at an age of 20-55 years in 1995-1997, who were followed-up to 2006-2008.

PRIMARY OUTCOME MEASURES

Incident diabetes was defined by self-report of diabetes or non-fasting glucose levels greater than 11 mmol/L at the follow-up.

METHODS

Multivariable logistic regression models were used to obtain OR with 95% CI for risk of diabetes by the categories of hours lying down (≤7, 8 and ≥9 hours/day).

RESULTS

362 individuals (2.1%) developed diabetes during an average of 11-year follow-up. Individuals who reported lying down ≥9 hours/day had an adjusted OR of 1.35 (95% CI 1.01 to 1.80) for incident diabetes compared with those lying down 8 hours/day. Lying down ≤7 hours/day was not associated with the risk of diabetes. In analysis stratified by physical activity, the ORs associated with lying down ≥9 hours/day were 1.41 (95% CI 1.05 to 1.90) and 0.90 (95% CI 0.23 to 3.55), respectively, among the less active and highly active individuals (p_interaction=0.048). There was little evidence that the association differed by BMI status (p_interaction=0.62).

CONCLUSIONS

Prolonged hours lying down per day was associated with an increased risk of diabetes in young and middle-aged adults. The positive association appeared to be modified by physical activity but not by BMI.

Sedentary behaviors and risk of depression: a meta-analysis of prospective studies

Epidemiological evidence on the association between sedentary behaviors and the risk of depression is inconsistent. We conducted a meta-analysis of prospective studies to identify the impact of sedentary behaviors on the risk of depression. We systematically searched in the PubMed and Embase databases to June 2019 for prospective cohort studies investigating sedentary behaviors in relation to the risk of depression. The pooled relative risks (RRs) and 95% confidence intervals (CIs) were calculated with random-effect meta-analysis. In addition, meta-regression analyses, subgroup analyses, and sensitivity analyses were performed to explore the potential sources of heterogeneity. Twelve prospective studies involving 128,553 participants were identified. A significantly positive association between sedentary behavior and the risk of depression was observed (RR = 1.10, 95% CI 1.03-1.19, I2 = 60.6%, P < 0.01). Subgroup analyses revealed that watching television was positively associated with the risk of depression (RR = 1.18, 95% CI 1.07-1.30), whereas using a computer was not (RR = 0.99, 95% CI 0.79-1.23). Mentally passive sedentary behaviors could increase the risk of depression (RR = 1.17, 95% CI 1.08-1.27), whereas the effect of mentally active sedentary behaviors were non-significant (RR = 0.98, 95% CI 0.83-1.15). Sedentary behaviors were positively related to depression defined by clinical diagnosis (RR = 1.08, 95% CI 1.03, 1.14), whereas the associations were statistically non-significant when depression was evaluated by the CES-D and the Prime-MD screening. The present study suggests that mentally passive sedentary behaviors, such as watching television, could increase the risk of depression. Interventions that reduce mentally passive sedentary behaviors may prevent depression.

The Role of Physical Therapists in Fighting the Type 2 Diabetes Epidemic

BACKGROUND

In 2014, the total prevalence of diabetes was estimated to be 422 million people worldwide. Due to the aging population and continued increase in obesity rates, the prevalence is expected to rise to 592 million by 2035. Diabetes can lead to several complications, including cardiovascular disease, stroke, peripheral arterial disease, nephropathy, neuropathy, retinopathy, lower extremity amputation, and musculoskeletal impairments.

CLINICAL QUESTION

Up to 80% of patients referred for outpatient physical therapy have diabetes or are at risk for diabetes, providing an opportunity for physical therapists to intervene. Therefore, we asked, "What is the role of physical therapists in fighting the diabetes epidemic?"

KEY RESULTS

Physical therapists commonly prescribe physical activity for the treatment of diabetes and other chronic diseases, such as cardiovascular disease and osteoarthritis. Physical therapists may also screen for risk factors for diabetes and diabetes-related complications and modify traditional musculoskeletal exercise prescription accordingly. Physical therapists must advocate for regular physical activity as a key component of the treatment of chronic diseases in all patient interactions.

CLINICAL APPLICATION

This commentary (1) describes the diabetes epidemic and the health impact of diabetes and diabetes-related complications, (2) highlights the physical therapist's role as front-line provider, and (3) provides recommendations for physical therapists in screening for diabetes risk factors and diabetes-related complications and considerations for patient management. We focus on type 2 diabetes. J Orthop Sports Phys Ther 2020;50(1):5-16. Epub 28 Nov 2019. doi:10.2519/jospt.2020.9154.

Physical Activity and Sedentary Time: Association with Metabolic Health and Liver Fat

Introduction/Purpose

To investigate whether (a) lower levels of daily physical activity (PA) and greater sedentary time accounted for contrasting metabolic phenotypes (higher liver fat/presence of metabolic syndrome [METS+] vs lower liver fat/absence of metabolic syndrome [METS−]) in individuals of similar body mass index and (b) the association of sedentary time on metabolic health and liver fat.

Methods

Ninety-eight habitually active participants (53 female, 45 male; age, 39 ± 13 yr; body mass index 26.9 ± 5.1 kg·m⁻²), underwent assessments of PA (SenseWear armband; wear time ~98%), cardiorespiratory fitness (V˙O₂ peak), body composition (magnetic resonance imaging and magnetic resonance spectroscopy) and multiorgan insulin sensitivity (oral glucose tolerance test). We undertook a) cross-sectional analysis comparing four groups: nonobese or obese, with and without metabolic syndrome (METS+ vs METS−) and b) univariate and multivariate regression for sedentary time and other levels of PA in relation to liver fat.

Results

Light, moderate, and vigorous PA did not account for differences in metabolic health between individuals, whether nonobese or obese, although METS+ individuals were more sedentary, with a higher number, and prolonged bouts (~1–2 h). Overall, sedentary time, average daily METS and V˙O₂ peak were each independently associated with liver fat percentage. Each additional hour of daily sedentary time was associated with a 1.15% (95% confidence interval, 1.14%–1.50%) higher liver fat content.

Conclusions

Greater sedentary time, independent of other levels of PA, is associated with being metabolically unhealthy; even in habitually active people, lesser sedentary time, and higher cardiorespiratory fitness and average daily METS is associated with lower liver fat.

Dasymaschalolactams A-E, Aristolactams from a Twig Extract of Dasymaschalon dasymaschalum

Five new aristolactam alkaloids (1-5), dasymaschalolactams A-E, and the first isolation of dasymaschalolactone (17) as a natural product, together with 19 known compounds (6-16 and 18-25) were isolated from the twig extract of Dasymaschalon dasymaschalum. Their structures were elucidated by spectroscopic methods as well as comparisons made from the literature. Compounds 20 and 21 showed α-glucosidase inhibitory activities with IC₅₀ values of 4.5 and 24.7 μM, respectively.

A "Sit Less, Walk More" Workplace Intervention for Office Workers: Long-Term Efficacy of a Quasi-Experimental Study

OBJECTIVE

This study tested the maintenance outcomes of a 3-month Sit Less, Walk More (SLWM) workplace intervention for office workers compared with usual care at 12 months from the baseline.

METHOD

A quasi-experimental study was conducted in two workplaces. The intervention group (n = 51) received multi-component intervention and the comparison group (n = 50) received newsletters only. The outcomes of the study (self-reported psychosocial, physical activity, sitting, and lost productivity; objectively measured cardiometabolic biomarkers) were compared at baseline, 3, and 12 months.

RESULTS

Generalized estimating equations analyses found that the intervention group had significant improvements in self-regulation for sitting less and moving more (P = 0.017), walking (P = 0.003), weight (P = 0.013), waist circumference (P = 0.002), and insulin (P = 0.000) at 12 months compared with the comparison group.

CONCLUSION

The SLWM intervention was effective in improving self-regulation, walking, and some cardiometabolic biomarkers in office workers.

Adipose Tissue-Derived Signatures for Obesity and Type 2 Diabetes: Adipokines, Batokines and MicroRNAs

: Obesity is one of the main risk factors for type 2 diabetes mellitus (T2DM). It is closely related to metabolic disturbances in the adipose tissue that primarily functions as a fat reservoir. For this reason, adipose tissue is considered as the primary site for initiation and aggravation of obesity and T2DM. As a key endocrine organ, the adipose tissue communicates with other organs, such as the brain, liver, muscle, and pancreas, for the maintenance of energy homeostasis. Two different types of adipose tissues-the white adipose tissue (WAT) and brown adipose tissue (BAT)-secrete bioactive peptides and proteins, known as "adipokines" and "batokines," respectively. Some of them have beneficial anti-inflammatory effects, while others have harmful inflammatory effects. Recently, "exosomal microRNAs (miRNAs)" were identified as novel adipokines, as adipose tissue-derived exosomal miRNAs can affect other organs. In the present review, we discuss the role of adipose-derived secretory factors-adipokines, batokines, and exosomal miRNA-in obesity and T2DM. It will provide new insights into the pathophysiological mechanisms involved in disturbances of adipose-derived factors and will support the development of adipose-derived factors as potential therapeutic targets for obesity and T2DM.

Real-time Mobile Monitoring of the Dynamic Associations Among Motor Activity, Energy, Mood, and Sleep in Adults With Bipolar Disorder

IMPORTANCE

Biologic systems involved in the regulation of motor activity are intricately linked with other homeostatic systems such as sleep, feeding behavior, energy, and mood. Mobile monitoring technology (eg, actigraphy and ecological momentary assessment devices) allows the assessment of these multiple systems in real time. However, most clinical studies of mental disorders that use mobile devices have not focused on the dynamic associations between these systems.

OBJECTIVES

To examine the directional associations among motor activity, energy, mood, and sleep using mobile monitoring in a community-identified sample, and to evaluate whether these within-day associations differ between people with a history of bipolar or other mood disorders and controls without mood disorders.

DESIGN, SETTING, AND PARTICIPANTS

This study used a nested case-control design of 242 adults, a subsample of a community-based sample of adults. Probands were recruited by mail from the greater Washington, DC, metropolitan area from January 2005 to June 2013. Enrichment of the sample for mood disorders was provided by volunteers or referrals from the National Institutes of Health Clinical Center or by participants in the National Institute of Mental Health Mood and Anxiety Disorders Program. The inclusion criteria were the ability to speak English, availability to participate, and consent to contact at least 2 living first-degree relatives. Data analysis was performed from June 2013 through July 2018.

MAIN OUTCOMES AND MEASURES

Motor activity and sleep duration data were obtained from minute-to-minute activity counts from an actigraphy device worn on the nondominant wrist for 2 weeks. Mood and energy levels were assessed by subjective analogue ratings on the ecological momentary assessment (using a personal digital assistant) by participants 4 times per day for 2 weeks.

RESULTS

Of the total 242 participants, 92 (38.1%) were men and 150 (61.9%) were women, with a mean (SD) age of 48 (16.9) years. Among the participants, 54 (22.3%) had bipolar disorder (25 with bipolar I; 29 with bipolar II), 91 (37.6%) had major depressive disorder, and 97 (40.1%) were controls with no history of mood disorders. A unidirectional association was found between motor activity and subjective mood level (β = -0.018, P = .04). Bidirectional associations were observed between motor activity (β = 0.176; P = .03) and subjective energy level (β = 0.027; P = .03) as well as between motor activity (β = -0.027; P = .04) and sleep duration (β = -0.154; P = .04). Greater cross-domain reactivity was observed in bipolar disorder across all outcomes, including motor activity, sleep, mood, and energy.

CONCLUSIONS AND RELEVANCE

These findings suggest that interventions focused on motor activity and energy may have greater efficacy than current approaches that target depressed mood; both active and passive tracking of multiple regulatory systems are important in designing therapeutic targets.

Sickness absence in pregnancy and sedentary behavior: a population-based cohort study from Norway

Background

Sickness absence in pregnancy accounts for a large part of sickness-related absenteeism among women. Exercise in pregnancy is associated with a lower level of sickness absence, however little is known about how sedentary behaviour is related to sickness absence in pregnancy. In the current study, we hypothesize a positive association between sedentary hours/day and the risk of long-term sickness absence.

Methods

Population-based cohort study of pregnant women attending three Child Health Clinics in Groruddalen, Oslo, 823 Women (74% of those eligible) were included between 2008 and 2010. Questionnaire data were collected at gestational weeks 10–20 (visit 1) and 28 (visit 2). Sedentary time and physical activity were objectively recorded at visit 1 with the multi-sensor SenseWear™ Pro3 Armband (SWA). Long-term sickness absence was self-reported at visit 2. We explored the association between sedentary time and long-term sickness absence in pregnancy using multiple logistic regression analysis.

Results

The odds of long-term sickness absence was significantly increased per one-hour increase in daily sedentary time (odds ratio 1.45 [95% confidence interval 1.13–1.84]), providing support for our hypothesis that sedentary time is positively associated with long-term sickness absence.

Conclusions

Pregnant women with a sedentary lifestyle have a higher risk of long-term sickness absence from work. Reducing sedentary time in pregnancy may improve health, and may, in turn reduce sickness absence in pregnancy.

Television viewing time, walking time, and risk of type 2 diabetes in Japanese men and women: The Japan Collaborative Cohort Study

We examined the effect of television viewing and walking on the risk of type 2 diabetes among an Asian population. A total of 25,240 participants (9786 men and 15,454 women) aged 40-79 years, with no history of diabetes, stroke, coronary heart disease, or cancer at the baseline (1988-1990) and who have completed the 5-year follow-up questionnaire were included. During the 5-year follow-up, 778 new cases of type 2 diabetes were reported (397 men and 381 women). Television viewing time was positively associated with risk of type 2 diabetes (p for trend = 0.01). The multivariable OR (95% CI) for ≥5 h/day versus <2 h/day television viewing was 1.51 (1.03-2.19) in women and 1.06 (0.71-1.59) in men (p for interaction = 0.82). Walking time was inversely associated with type 2 diabetes risk in a fully adjusted model (p for trend = 0.02). The multivariable OR for type 2 diabetes of ≥1 h/day walking time was 0.87 (0.71-1.06) compared with 0.5 h/day walking time. The inverse association was found in men (p for trend = 0.02), but not in women (p for trend = 0.38) (p for interaction = 0.36). The multivariable OR for type 2 diabetes of <5 h/day television viewing and ≥1 h/day walking times was 0.72 (0.55-0.94) in fully adjusted model compared with ≥5 h/day television viewing and <1 h/day walking times. Limiting television viewing time and increasing walking time may reduce risk of type 2 diabetes among Japanese.

Reductions in whole-body fat mass but not increases in lean mass predict changes in cardiometabolic health indices with exercise training among weight-stable adults

We assessed whether body composition changes with 9 months of exercise training predicted changes in cardiometabolic health indices in weight-stable adults. We hypothesized that within ±5% weight change, changes in whole-body fat and lean masses would predict changes in cardiometabolic health indices with exercise training. Using a randomized parallel design, 152 adults (age: 49 ± 8 year; body mass index: 30.0 ± 2.7 kg/m²; mean ± SD) performed resistance exercises 2 d/wk and aerobic exercises 1 d/wk for 9 months. Participants consumed isoenergetic supplements with 0, 10, 20, or 30 g whey protein twice daily and remained weight stable within ±5% of baseline weight. Body weight and composition were measured using dual-energy x-ray absorptiometry pre- and postintervention. Multiple linear regression model was applied for data analyses. Independent of whey protein supplementation, reductions in fat mass predicted increases in high-density lipoprotein cholesterol (unstandardized beta-coefficient [β], -0.03; 95% confidence interval [CI], -0.06 to -0.01; P = .007) and insulin sensitivity index (β, -0.52; 95% CI, -0.95 to -0.09; P = .018) and decreases in waist circumference (β, 0.67; 95% CI, 0.17-1.18; P = .009). In contrast, increases in lean mass did not predict changes in any of the measured cardiometabolic health indices. Health improvements with training that emphasize resistance exercises are typically attributed to increases in lean mass; however, these results underscore reducing body fat to predict cardiometabolic health improvements.

Prevalence and social and health determinants of pre-diabetes and diabetes among adults in Laos: a cross-sectional national population-based survey, 2013

OBJECTIVE

Diabetes is a major and fast-growing public health problem in Southeast Asia. We determined the prevalence of pre-diabetes and diabetes and assessed the levels of awareness, treatment and control in Lao People's Democratic Republic (PDR).

METHODS

A national cross-sectional study based on a stratified cluster random sampling was conducted in 2013. The sample comprised 2492 individuals aged 18-64 years (59.3% females; mean age 38.7 years, SD = 12.8) from Lao PDR. We followed the WHO STEPS method: step 1, questionnaire interview; step 2, anthropometric and Blood Pressure (BP) measurements; and step 3, biochemistry tests. Multinominal logistic regression was used to investigate the determinants of pre-diabetes and diabetes (fasting plasma glucose levels ≥ 7.0 mmol/L; or using insulin or oral hypoglycaemic drugs; or having a history of diagnosis of diabetes).

RESULTS

5.7% of the population had diabetes, 4.7% of men and 6.4% of women, and 2.3% had pre-diabetes, 1.8% of men and 2.6% of women. Only 14.1% of the population sample indicated that they had ever their blood glucose measured by a health-care worker. This was higher in urban (20.9%) than rural (10.9%) dwellers (P < 0.001), and among female (16.6%) than male (10.5%) participants (P < 0.001). Among those with diabetes, 58.1% were aware of their diabetes status, 40.3% were taking treatment and 10.9% had controlled diabetes. The factor independently associated with impaired fasting glycaemia (IFG) or pre-diabetes was central obesity (Adjusted Relative Risk Ratio-ARRR: 3.92, Confidence Interval-CI: 1.89, 8.14) but none of the other health (general body weight, fruit and vegetable consumption, physical activity, substance use, hypertension and cholesterol) and sociodemographic (age, sex, education, employment status, marital status, ethno-linguistic group and residence status) variables. Factors independently associated with diabetes were older age (ARRR: 5.12, CI: 1.55, 10.20), central obesity (ARRR: 2.15, CI: 1.16, 4.00), low or moderate physical activity (ARRR: 0.75, CI: 0.60, 0.93), having hypertension (ARRR: 1.68, CI: 1.01, 2.83), and dyslipidaemia (ARRR: 1.75, CI: 1.08, 2.81).

CONCLUSION

A public health response is needed in the form of integrated and comprehensive action targeting major non-communicable diseases in the country.

Sedentary behaviour in rheumatoid arthritis: definition, measurement and implications for health

RA is a chronic autoimmune disease characterized by high grade-inflammation, and associated with elevated cardiovascular risk, rheumatoid-cachexia and functional impairment. Sedentary behaviour (SB) is linked to heightened inflammation, and is highly pervasive in RA, likely as a result of compromised physical function and persistent fatigue. This high sedentarity may exacerbate the inflammatory process in RA, and hold relevance for disease-related outcomes. The aim of this narrative review is to provide an overview of the definition, measurement and health relevance of SB in the context of RA. Contradictions are highlighted with regard to the manner in which SB is operationalized, and the significance of SB for disease outcomes in RA is outlined. The advantages and disadvantages of SB measurement approaches are also discussed. Against this background, we summarize studies that have reported SB and its health correlates in RA, and propose directions for future research.

Variability and reliability study of overall physical activity and activity intensity levels using 24 h-accelerometry-assessed data

Background

24 h-accelerometry is now used to objectively assess physical activity (PA) in many observational studies like the German National Cohort; however, PA variability, observational time needed to estimate habitual PA, and reliability are unclear.

Methods

We assessed 24 h-PA of 50 participants using triaxial accelerometers (ActiGraph GT3X+) over 2 weeks. Variability of overall PA and different PA intensities (time in inactivity and in low intensity, moderate, vigorous, and very vigorous PA) between days of assessment or days of the week was quantified using linear mixed-effects and random effects models. We calculated the required number of days to estimate PA, and calculated PA reliability using intraclass correlation coefficients.

Results

Between- and within-person variance accounted for 34.4–45.5% and 54.5–65.6%, respectively, of total variance in overall PA and PA intensities over the 2 weeks. Overall PA and times in low intensity, moderate, and vigorous PA decreased slightly over the first 3 days of assessment. Overall PA (p = 0.03), time in inactivity (p = 0.003), in low intensity PA (p = 0.001), in moderate PA (p = 0.02), and in vigorous PA (p = 0.04) slightly differed between days of the week, being highest on Wednesday and Friday and lowest on Sunday and Monday, with apparent differences between Saturday and Sunday. In nested random models, the day of the week accounted for < 19% of total variance in the PA parameters. On average, the required number of days to estimate habitual PA was around 1 week, being 7 for overall PA and ranging from 6 to 9 for the PA intensities. Week-to-week reliability was good (intraclass correlation coefficients, range, 0.68–0.82).

Conclusions

Individual PA, as assessed using 24 h-accelerometry, is highly variable between days, but the day of assessment or the day of the week explain only small parts of this variance. Our data indicate that 1 week of assessment is necessary for reliable estimation of habitual PA.

Electronic supplementary material

The online version of this article (10.1186/s12889-018-5415-8) contains supplementary material, which is available to authorized users.

The Necessity of Active Muscle Metabolism for Healthy Aging: Muscular Activity Throughout the Entire Day

There is more need for "a movement-movement" than ever before. The percentage of seniors in our population is rising exponentially. Sedentary lifestyles throughout the lifespan have become the norm, including inactive youth and a sedentary workforce. Preventable chronic diseases caused by sedentary living have both lowered the quality of life for those directly affected or their families, and have created an unsustainable economic dilemma. In this article, we explain that whether it is a sedentary student, worker, or retiree, the most neglected but essential facts are as follows. By far, the most potent and rapid way to raise the rate of healthy metabolic and cardiovascular processes is through the immediate benefits of muscle contractions. Working muscle demands more energy and fuel than any other tissue in the body, but during inactivity the metabolic rate of muscle is relatively low. Depending on the type of contraction, muscle type, and other factors, the local fuel requirements within the working muscle can help to manage metabolic risks through a variety of processes, such as blood glucose utilization, uptake of unhealthy blood triglycerides, and increased blood flow. Given the large amount of time that people spend inactive each day, there is an enormous opportunity to raise the bar in optimizing health throughout the entire lifespan. Developed correctly, safe and low effort muscular activity can be performed for relatively long periods of time each day by the elderly and all segments of the population to optimize health and well being during aging.

Multiple Short Bouts of Walking Activity Attenuate Glucose Response in Obese Women

BACKGROUND

We sought to determine the effect of multiple walking breaks from sedentary behavior (SED) on glucose responses in sedentary obese women.

MATERIALS AND METHODS

Ten women [aged = 36 (5) y, body mass index = 38.0 (1.6) kg/m², body fat = 49.6 (1.4)%] completed 3 conditions (48-h "washout" in-between conditions) following a standardized meal in random order: 4-hour SED, 4-hour SED with 2 minutes of moderate-intensity walking every 30 minutes (SED + 2 min), and 4-hour SED with 5 minutes of moderate-intensity walking every 30 minutes (SED + 5 min). Measurements included continuous interstitial glucose concentration monitoring immediately before and during standardized conditions and accelerometry for physical activity patterns during and in-between the standardized conditions. Repeated-measures 1-way analyses of variance (α = .05) with Bonferroni correction for post hoc comparisons were performed. Effect sizes (d [95% confidence interval]) were calculated as mean difference from SED/pooled standard deviation.

RESULTS

Sedentary time was similar in the 48 hours preceding each condition (P > .05). By design, sedentary time was different between conditions (P < .001). Compared with SED, 2-hour postprandial glucose positive incremental area under the curve was lower for SED + 5 minutes (P = .005; d = - 0.57 [-1.48, 0.40]), but not for SED + 2 minutes (P = .086; d = - 0.71 [-1.63, 0.27]). Four-hour postprandial glucose area under the curve was similar between conditions (P > .05).

CONCLUSION

In sedentary obese women, 5 minutes of moderate-intensity walking breaks from SED each 30 minutes attenuate 2-hour postprandial glucose excursions.

Factors associated with physical activity levels in people with venous leg ulcers: A multicentre, prospective, cohort study

Increasing levels of physical activity among people with venous leg ulcers (VLUs) can potentially reduce the health cost burden, improve functional aspects of patients' lives and increase ulcer healing rates. The aim of this study was to investigate factors associated with physical activity levels in patients with VLUs. Data from 2016 to 2017 Aspirin for Venous Leg Ulcer cohort study were analysed for the present study. Ninety participants were recruited from 5 outpatient specialist wound clinics across Victoria, Australia between August 2016 and April 2017. There was a statistically significant association between diabetes and physical activity, with a higher proportion of people with type 2 diabetes in the sedentary category. Further, there was a statistically significant association between patient-reported VLU education and physical activity levels. An indirect advantage of relevant, easy-to-understand education about VLUs may increase physical activity levels, which may facilitate improved time to healing of VLUs.

Replacement Effects of Sedentary Time on Metabolic Outcomes: The Maastricht Study

INTRODUCTION

Sedentary time has been associated with detrimental health effects, so in some countries, guidelines to reduce sedentary time have been developed. As reducing sedentary time inevitably results in more nonsedentary time, effects of this reduction may depend on the activity with which it is replaced.

PURPOSE

This study aimed to examine associations of theoretical reallocations of sedentary time to standing or stepping with cardiometabolic outcomes and type 2 diabetes.

METHODS

We included 2213 participants (51% men, mean ± SD age = 60.0 ± 8.1 yr) of the Maastricht Study who were asked to wear an accelerometer 24 h·d for a week. We calculated daily sedentary, standing, and stepping time. An isotemporal substitution modeling approach was applied to examine effects on waist circumference; body mass index; cholesterol, triacylglycerol, glucose, and insulin levels; metabolic syndrome; and type 2 diabetes.

RESULTS

Replacement of sedentary time (30 min·d) with stepping was associated with lower odds for metabolic syndrome (odds ratio [OR] = 0.72, 95% confidence interval [CI] = 0.66-0.78) and type 2 diabetes (OR = 0.79, 95% CI = 0.72-0.87), more favorable waist circumference (B = -1.42, 95% CI = -1.78 to -1.06), and body mass index (B = -0.48, 95% CI = -0.62 to -0.35) and improved cholesterol, triacylglycerol, glucose, and insulin levels. Replacing sedentary time with standing was associated with lower odds for metabolic syndrome and type 2 diabetes and favorable outcomes in waist circumference, cholesterol, triacylglycerol, and insulin levels.

CONCLUSION

Theoretical replacements of sedentary time with nonsedentary time (both standing and stepping) were associated with lower odds for metabolic syndrome, type 2 diabetes, and beneficial metabolic outcomes. These results could be important for the general population, including those who cannot meet physical activity guidelines. Consideration should be given to developing recommendations for daily reallocating sedentary time.

Correlates of accelerometer-assessed physical activity and sedentary time among adults with type 2 diabetes

OBJECTIVES

The aims of this study were to describe the volume and patterns of objectively assessed sedentary behaviour, light intensity physical activity (LPA) and moderate-vigorous physical activity (MVPA), and to examine socio-demographic correlates, among adults living with type 2 diabetes.

METHODS

Participants (n = 166) wore an accelerometer (Actigraph® GT3X+) for seven consecutive days during waking hours and completed a questionnaire. Physical activity (PA) and sedentary time were described, and multivariable linear regression was used to estimate associations between socio-demographic characteristics and sedentary time and PA.

RESULTS

Participants, 46% of whom were female, had a mean age of 65.4 years (standard deviation (SD) = 9.5), body mass index (BMI) of 31.5 (6.6) kg/m2 and had been living with diabetes for an average of 13.1 (7.6) years. Participants were sedentary for 543.6 minutes/day, spent 273.4 minutes/day and 22.4 minutes/day in LPA and MVPA respectively. BMI was associated with increased sedentary time and reduced LPA (-2.5 minutes/day, 95% CI: -4.33 to -0.70) and MVPA (-0.62 minutes/day, 95% CI: -1.05 to -0.18) time. Compared with males, females had more LPA (34.4 minutes/day, 95% CI: 10.21-58.49) and less MVPA (-6.2 minutes/day, 95% CI: -12.04 to -0.41) time. Unemployed participants had 30.05 minutes more MVPA (95% CI: 3.35-56.75) than those who were employed or homemakers, and those not reporting income had 13 minutes/day more MVPA time than participants in the lowest income category (95% CI: 3.46-22.40).

CONCLUSION

Adults living with type 2 diabetes were not sufficiently active and were highly sedentary. Our results emphasize the need for more research exploring the diabetes-related health outcomes of sedentary behaviour and physical inactivity among people living with type 2 diabetes.

Exercise training dose differentially alters muscle and heart capillary density and metabolic functions in an obese rat with metabolic syndrome

NEW FINDINGS

What is the central question of this study? Regular exercise is recommended as a non-pharmacological approach for the prevention and treatment of metabolic syndrome. However, the impact of different combinations of intensity, duration and frequency of exercise on metabolic syndrome and microvascular density has not been reported. What is the main finding and its importance? We provide evidence on the impact of aerobic exercise dose on metabolic and microvascular alterations in an experimental model of metabolic syndrome induced by high-fat diet. We found that the exercise frequency and duration were the main factors affecting anthropometric and metabolic parameters and microvascular density in the skeletal muscle. Exercise intensity was related only to microvascular density in the heart. We evaluated the effect of the frequency, duration and intensity of exercise training on metabolic parameters and structural capillary density in obese rats with metabolic syndrome. Wistar-Kyoto rats were fed either a standard commercial diet (CON) or a high-fat diet (HFD). Animals that received the HFD were randomly separated into either a sedentary (SED) group or eight different exercise groups that varied according to the frequency, duration and intensity of training. After 12 weeks of aerobic exercise training, the body composition, aerobic capacity, haemodynamic variables, metabolic parameters and capillary density in the heart and skeletal muscle were evaluated. All the exercise training groups showed reduced resting systolic blood pressure and heart rate and normalized fasting glucose. The minimal amount of exercise (90 min per week) produced little effect on metabolic syndrome parameters. A moderate amount of exercise (150 min per week) was required to reduce body weight and improve capillary density. However, only the high amount of exercise (300 min per week) significantly reduced the amount of body fat depots. The three-way ANOVA showed a main effect of exercise frequency and duration for the improvement of metabolic syndrome and capillary density in skeletal muscle. Exercise intensity was a main factor in reversing microvascular rarefaction in the heart.

Formative Assessment: Design of a Web-Connected Sedentary Behavior Intervention for Females

Background

Sedentary behavior (SB) is a significant risk factor for heart disease, diabetes, obesity, and early mortality, particularly among women, and the health consequences associated with SB are independent of physical activity status. Interventions utilizing wearable technologies can improve SB, but their effectiveness is influenced by individual preferences, device engagement strategies, and technological features, which may affect user compliance. Gathering a priori insight from target populations on their preferences for program tools and strategies may assist researchers in identifying effective methods to improve the efficacy of SB interventions.

Objective

The objective of this study was to (1) explore the likeability (likes and dislikes) and usability (engagement intentions and navigation) of a wearable device (Movband) and its accompanying website (dashboard), (2) examine social incentive preferences (teammates), and (3) assess the feasibility (participants’ experiences during an activity-monitoring period) of these tools for use in an intervention to reduce SB in girls and women.

Methods

A total of 9 girls (mean age: 8.9 years, standard deviation [SD] 1.1 years) and 11 college-aged women (mean age: 22.6 years, SD 3.2 years) participated in this study. Separate focus groups were held for girls and women, and all participants attended one before and the other following a 7-day activity-monitoring period. During the focus groups, participants were prompted with questions to address the study aims, and the nominal group technique was used to compile lists of group-specific preferences for the activity-monitoring system. The top three ranking likes and dislikes were reverse coded to determine likeability.

Results

The top-ranking responses for the girls and women were the following: visual display of movements and ease of navigation (dashboard like), boring to look at and no calorie-tracking function (dashboard dislike), backlight and long battery life (Movband like), and color and not waterproof (tied for girls) and vertical time display (Movband dislike). Additionally, participants identified several aesthetic preferences and functional limitations. At the second focus group visit, the majority of the participants self-reported less SB during the previous week. Objective data from the activity-monitoring period revealed that the average steps per day for girls and women were 12,373.4 (SD 2617.6) and 8515.8 (SD 3076.7), respectively.

Conclusions

These results suggest that the girls and women liked many features of the Movband and dashboard. However, several dislikes were mentioned, which may negatively influence compliance and the effectiveness of the activity-monitoring system and require improvements before using in an SB intervention.

The sedentary (r)evolution: Have we lost our metabolic flexibility?

During the course of evolution, up until the agricultural revolution, environmental fluctuations forced the human species to develop a flexible metabolism in order to adapt its energy needs to various climate, seasonal and vegetation conditions. Metabolic flexibility safeguarded human survival independent of food availability. In modern times, humans switched their primal lifestyle towards a constant availability of energy-dense, yet often nutrient-deficient, foods, persistent psycho-emotional stressors and a lack of exercise. As a result, humans progressively gain metabolic disorders, such as the metabolic syndrome, type 2 diabetes, non-alcoholic fatty liver disease, certain types of cancer, cardiovascular disease and Alzheimer´s disease, wherever the sedentary lifestyle spreads in the world. For more than 2.5 million years, our capability to store fat for times of food shortage was an outstanding survival advantage. Nowadays, the same survival strategy in a completely altered surrounding is responsible for a constant accumulation of body fat. In this article, we argue that the metabolic disease epidemic is largely based on a deficit in metabolic flexibility. We hypothesize that the modern energetic inflexibility, typically displayed by symptoms of neuroglycopenia, can be reversed by re-cultivating suppressed metabolic programs, which became obsolete in an affluent environment, particularly the ability to easily switch to ketone body and fat oxidation. In a simplified model, the basic metabolic programs of humans' primal hunter-gatherer lifestyle are opposed to the current sedentary lifestyle. Those metabolic programs, which are chronically neglected in modern surroundings, are identified and conclusions for the prevention of chronic metabolic diseases are drawn.

The sedentary (r)evolution: Have we lost our metabolic flexibility?

During the course of evolution, up until the agricultural revolution, environmental fluctuations forced the human species to develop a flexible metabolism in order to adapt its energy needs to various climate, seasonal and vegetation conditions. Metabolic flexibility safeguarded human survival independent of food availability. In modern times, humans switched their primal lifestyle towards a constant availability of energy-dense, yet often nutrient-deficient, foods, persistent psycho-emotional stressors and a lack of exercise. As a result, humans progressively gain metabolic disorders, such as the metabolic syndrome, type 2 diabetes, non-alcoholic fatty liver disease, certain types of cancer, cardiovascular disease and Alzheimer´s disease, wherever the sedentary lifestyle spreads in the world. For more than 2.5 million years, our capability to store fat for times of food shortage was an outstanding survival advantage. Nowadays, the same survival strategy in a completely altered surrounding is responsible for a constant accumulation of body fat. In this article, we argue that the metabolic disease epidemic is largely based on a deficit in metabolic flexibility. We hypothesize that the modern energetic inflexibility, typically displayed by symptoms of neuroglycopenia, can be reversed by re-cultivating suppressed metabolic programs, which became obsolete in an affluent environment, particularly the ability to easily switch to ketone body and fat oxidation. In a simplified model, the basic metabolic programs of humans’ primal hunter-gatherer lifestyle are opposed to the current sedentary lifestyle. Those metabolic programs, which are chronically neglected in modern surroundings, are identified and conclusions for the prevention of chronic metabolic diseases are drawn.

Dysregulation of objectively assessed 24-hour motor activity patterns as a potential marker for bipolar I disorder: results of a community-based family study

There has been a growing number of studies that have employed actigraphy to investigate differences in motor activity in mood disorders. In general, these studies have shown that people with bipolar disorders (BPDs) tend to exhibit greater variability and less daytime motor activity than controls. The goal of this study was to examine whether patterns of motor activity differ in euthymic individuals across the full range of mood disorder subtypes (Bipolar I (BPI), Bipolar II (BPII) and major depression (MDD)) compared with unaffected controls in a community-based family study of mood spectrum disorders. Minute-to-minute activity counts derived from actigraphy were collected over a 2-week period for each participant. Prospective assessments of the level, timing and day-to-day variability of physical activity measures were compared across diagnostic groups after controlling for a comprehensive list of potential confounding factors. After adjusting for the effects of age, sex, body mass index (BMI) and medication use, the BPI group had lower median activity intensity levels across the second half of the day and greater variability in the afternoon compared with controls. Those with a history of BPII had increased variability during the night time compared with controls, indicating poorer sleep quality. No differences were found in the average intensity, variability or timing of activity in comparisons between other mood disorder subgroups and controls. Findings confirm evidence from previous studies that BPI may be a manifestation of a rhythm disturbance that is most prominent during the second half of the day. The present study is the largest study to date that included the full range of mood disorder subgroups in a nonclinical sample that increases the generalizability of our findings to the general community. The manifestations of activity patterns outside of acute episodes add to the accumulating evidence that dysregulation of patterns of activity may constitute a potential biomarker for BPD.

The role of skeletal muscle contractile duration throughout the whole day: reducing sedentary time and promoting universal physical activity in all people

A shared goal of many researchers has been to discover how to improve health and prevent disease, through safely replacing a large amount of daily sedentary time with physical activity in everyone, regardless of age and current health status. This involves contrasting how different muscle contractile activity patterns regulate the underlying molecular and physiological responses impacting health‐related processes. It also requires an equal attention to behavioural feasibility studies in extremely unfit and sedentary people. A sound scientific principle is that the body is constantly sensing and responding to changes in skeletal muscle metabolism induced by contractile activity. Because of that, the rapid time course of health‐related responses to physical inactivity/activity patterns are caused in large part directly because of the variable amounts of muscle inactivity/activity throughout the day. However, traditional modes and doses of exercise fall far short of replacing most of the sedentary time in the modern lifestyle, because both the weekly frequency and the weekly duration of exercise time are an order of magnitude less than those for people sitting inactive. This can explain why high amounts of sedentary time produce distinct metabolic and cardiovascular responses through inactivity physiology that are not sufficiently prevented by low doses of exercise. For these reasons, we hypothesize that maintaining a high metabolic rate over the majority of the day, through safe and sustainable types of muscular activity, will be the optimal way to create a healthy active lifestyle over the whole lifespan.

Environmental/lifestyle factors in the pathogenesis and prevention of type 2 diabetes

BACKGROUND

Environmental and lifestyle changes, in addition to the ageing of populations, are generally believed to account for the rapid global increase in type 2 diabetes prevalence and incidence in recent decades.

DISCUSSION

In this review, we present a comprehensive overview of factors contributing to diabetes risk, including aspects of diet quality and quantity, little physical activity, increased monitor viewing time or sitting in general, exposure to noise or fine dust, short or disturbed sleep, smoking, stress and depression, and a low socioeconomic status. In general, these factors promote an increase in body mass index. Since loss of β-cell function is the ultimate cause of developing overt type 2 diabetes, environmental and lifestyle changes must have resulted in a higher risk of β-cell damage in those at genetic risk. Multiple mechanistic pathways may come into play.

CONCLUSIONS

Strategies of diabetes prevention should aim at promoting a 'diabetes-protective lifestyle' whilst simultaneously enhancing the resistance of the human organism to pro-diabetic environmental and lifestyle factors. More research on diabetes-protective mechanisms seems warranted.

Environmental/lifestyle factors in the pathogenesis and prevention of type 2 diabetes

BACKGROUND

Environmental and lifestyle changes, in addition to the ageing of populations, are generally believed to account for the rapid global increase in type 2 diabetes prevalence and incidence in recent decades.

DISCUSSION

In this review, we present a comprehensive overview of factors contributing to diabetes risk, including aspects of diet quality and quantity, little physical activity, increased monitor viewing time or sitting in general, exposure to noise or fine dust, short or disturbed sleep, smoking, stress and depression, and a low socioeconomic status. In general, these factors promote an increase in body mass index. Since loss of β-cell function is the ultimate cause of developing overt type 2 diabetes, environmental and lifestyle changes must have resulted in a higher risk of β-cell damage in those at genetic risk. Multiple mechanistic pathways may come into play.

CONCLUSIONS

Strategies of diabetes prevention should aim at promoting a 'diabetes-protective lifestyle' whilst simultaneously enhancing the resistance of the human organism to pro-diabetic environmental and lifestyle factors. More research on diabetes-protective mechanisms seems warranted.

Sedentary behaviour is a key determinant of metabolic inflexibility

Metabolic flexibility is defined as the ability to adapt substrate oxidation rates in response to changes in fuel availability. The inability to switch between the oxidation of lipid and carbohydrate appears to be an important feature of chronic disorders such as obesity and type 2 diabetes. Laboratory assessment of metabolic flexibility has traditionally involved measurement of the respiratory quotient (RQ) by indirect calorimetry during the fasted to fed transition (e.g. mixed meal challenge) or during a hyperinsulinaemic-euglycaemic clamp. Under these controlled experimental conditions, 'metabolic inflexibility' is characterized by lower fasting fat oxidation (higher fasting RQ) and/or an impaired ability to oxidize carbohydrate during feeding or insulin-stimulated conditions (lower postprandial or clamp RQ). This experimental paradigm has provided fundamental information regarding the role of substrate oxidation in the development of obesity and insulin resistance. However, the key determinants of metabolic flexibility among relevant clinical populations remain unclear. Herein, we propose that habitual physical activity levels are a primary determinant of metabolic flexibility. We present evidence demonstrating that high levels of physical activity predict metabolic flexibility, while physical inactivity and sedentary behaviours trigger a state of metabolic 'inflexibility', even among individuals who meet physical activity recommendations. Furthermore, we describe alternative experimental approaches to studying the concept of metabolic flexibility across a range of activity and inactivity. Finally, we address the promising use of strategies that aim to reduce sedentary behaviours as therapy to improve metabolic flexibility and reduce weight gain risk.

Health-related behaviors and mortality outcomes in women diagnosed with ductal carcinoma in situ

PURPOSE

Women diagnosed with ductal carcinoma in situ (DCIS) of the breast are at greater risk of dying from cardiovascular disease and other causes than from breast cancer, yet associations between health-related behaviors and mortality outcomes after DCIS have not been well studied.

METHODS

We examined the association of body mass index, physical activity, alcohol consumption, and smoking with mortality among 1925 women with DCIS in the Wisconsin In Situ Cohort study. Behaviors were self-reported through baseline interviews and up to three follow-up questionnaires. Cox proportional hazards regression was used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for mortality after DCIS, with adjustment for patient sociodemographic, comorbidity, and treatment factors.

RESULTS

Over a mean of 6.7 years of follow-up, 196 deaths occurred. All-cause mortality was elevated among women who were current smokers 1 year prior to diagnosis (HR = 2.17 [95% CI 1.48, 3.18] vs. never smokers) and reduced among women with greater physical activity levels prior to diagnosis (HR = 0.55 [95% CI: 0.35, 0.87] for ≥5 h per week vs. no activity). Moderate levels of post-diagnosis physical activity were associated with reduced all-cause mortality (HR = 0.31 [95% CI 0.14, 0.68] for 2-5 h per week vs. no activity). Cancer-specific mortality was elevated among smokers and cardiovascular disease mortality decreased with increasing physical activity levels.

CONCLUSIONS

There are numerous associations between health-related behaviors and mortality outcomes after a DCIS diagnosis.

IMPLICATIONS FOR CANCER SURVIVORS

Women diagnosed with DCIS should be aware that their health-related behaviors are associated with mortality outcomes.

A new aspect of chronic pain as a lifestyle-related disease

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Activation of mesolimbic dopamine system underlies exercise-induced hypoalgesia.

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Interaction between mesolimbic system and hypothalamus determines physical activity.

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Changing the lifestyle inactive to active may attenuate and prevent chronic pain.

Physical exercise has been established as a low-cost, safe, and effective way to manage chronic intractable pain. We investigated the underlying mechanisms of exercise-induced hypoalgesia (EIH) using a mouse model of neuropathic pain (NPP). Epigenetic changes in activated microglia and maintained GABA synthesis in the spinal dorsal horn may contribute to EIH. Voluntary exercise (VE), a strong reward for animals, also induced EIH, which may be due in part to the activation of dopamine (DA) neurons in the ventral tegmental area (VTA). VE increases the expression of pCREB in dopaminergic neurons in the VTA, which would enhance dopamine production, and thereby contributes to the activation of the mesolimbic reward system in NPP model mice. We demonstrated that neurons in the laterodorsal tegmental and pedunculopontine tegmental nuclei, a major input source of rewarding stimuli to the VTA, were activated by exercise.

Chronic pain is at least partly attributed to sedentary and inactive lifestyle as indicated by the Fear-avoidance model. Therefore, chronic pain could be recognized as a lifestyle-related disease. Physical activity/inactivity may be determined by genetic/epigenetic and neural factors encoded in our brain. The hypothalamus and reward system is closely related in the axis of food intake, energy metabolism and physical activity. Understanding the interactions between the mesolimbic DA system and the hypothalamus that sense and regulate energy balance is thus of significant importance. For example, proopiomelanocortin neurons and melanocortin 4 receptors may play a role in connecting these two systems. Therefore, in a certain sense, chronic pain and obesity may share common behavioral and neural pathology, i.e. physical inactivity, as a result of inactivation of the mesolimbic DA system. Exercise and increasing physical activity in daily life may be important in treating and preventing chronic pain, a life-style related disease.

Leisure sedentary time is differentially associated with hypertension, diabetes mellitus, and hyperlipidemia depending on occupation

Background

Sedentary behavior is considered an independent cause of cardio-metabolic diseases, regardless of physical activity level and obesity. Few studies have reported the association between leisure sedentary time and cardio-vascular diseases in terms of occupation.

Methods

We performed a cross-sectional study using data from the Korean Community Health Survey (KCHS) for 240,086 participants assessed in 2011 and 2013. Occupation was categorized into four groups: farmer or fisherman, laborer, and soldier (Group I); service worker, salesperson, technician, mechanic, production worker, and engineer (Group II); manager, expert, specialist, and clerk (Group III); and unemployed (Group IV). Leisure sedentary time was divided into five groups: 0 h, 1 h, 2 h, 3 h, and 4+ h. The association between leisure sedentary time on weekdays and hypertension/diabetes mellitus/hyperlipidemia for different occupations was analyzed using simple and multiple logistic regression analyses with complex sampling.

Results

In Groups I, II and III, no length of sedentary time was associated with hypertension, and only 3 h or 4+ h of sedentary time was associated with diabetes mellitus and hyperlipidemia. Group IV showed a significant association with hypertension and diabetes mellitus for the 2 h, 3 h, and 4+ h sedentary times.

Conclusions

The unemployed are more susceptible than other occupation groups to cardio-metabolic diseases when leisure time is sedentary.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-017-4192-0) contains supplementary material, which is available to authorized users.

What is the metabolic and energy cost of sitting, standing and sit/stand transitions?

PURPOSE

Modern lifestyles require people to spend prolonged periods of sitting, and public health messages recommend replacing sitting with as much standing as is feasible. The metabolic/energy cost (MEC) of sitting and standing is poorly understood, and MEC associated with a transition from sitting to standing has not been reported. Thus, we carefully quantified the MEC for sitting, standing and sit/stand transitions, adjusting for age and fat-free mass (FFM) in a sample of adults with no known disease.

METHODS

Participants (N = 50; 25 women), 20–64 years, randomly performed three conditions for 10 min each (sitting, standing, 1 sit/stand transition min(−1) and then sitting back down). MEC was measured by indirect calorimetry and FFM by dual-energy X-ray absorptiometry.

RESULTS

V̇O2 (ml kg(−1) min(−1)) for sitting (2.93 ± 0.61; 2.87 ± 0.37 in men and women respectively), standing (3.16 ± 0.63; 3.03 ± 0.40), and steady-state cost of repeated sit/stand transitions (1 min(−1)) (3.86 ± 0.75; 3.79 ± 0.57) were significantly different regardless of sex and weight (p < 0.001). EE (kcal min(−1)) also differed from sitting (1.14 ± 0.18; 0.88 ± 0.11), to standing (1.23 ± 0.19; 0.92 ± 0.13), and sit/stand transitions (1 min(−1)) (1.49 ± 0.25; 1.16 ± 0.16). Heart-rate increased from sitting to standing (~13 bpm; p < 0.001). Neither sex nor FFM influenced the results (p ≥ 0.05).

CONCLUSIONS

This study found in a sample of adults with no known disease that continuous standing raised MEC 0.07 kcal min(−1) above normal sitting. The transition from sitting to standing (and return to sitting) had a metabolic cost of 0.32 kcal min(−1) above sitting. Therefore, public health messages recommending to interrupt sitting frequently should be informed of the modest energetic costs regardless of sex and body composition.

Chair-based fidgeting and energy expenditure

Introduction

Sedentariness is associated with chronic health conditions, impaired cognitive function and obesity. Work contributes significantly to sedentariness because many work tasks necessitate sitting. Few sustained solutions exist to reverse workplace sedentariness. Here, we evaluated a chair and an under-table device that were designed to promote fidgeting while seated. Our hypothesis was that an under-table leg-fidget bar and/or a fidget-promoting chair significantly increased energy expenditure. We compared these devices with chair-based exercise and walking.

Materials and methods

We measured energy expenditure and heart rate in 16 people while they sat and worked using a standard chair, an under-desk device that encourages leg fidgeting and a fidget-promoting chair. We compared outcomes with chair-based exercise and walking.

Results

Energy expenditure increased significantly while using either an under-table leg-fidget bar or a fidget-promoting chair, when compared to the standard office chair (standard chair, 76±31 kcal/hour; leg-fidget bar, 98±42 kcal/hour (p<0.001); fidget chair, 89±40 kcal/hour (p=0.03)). However, heart rate did not increase significantly in either case. Bouts of exercise performed while seated provided energetic and heart rate equivalency to walking at 2 mph.

Conclusions

Chairs and devices that promote fidgeting can increase energy expenditure by ∼20–30% but not increase heart rate. Dynamic sitting may be among a lexicon of options to help people move more while at work.

Lifestyle interventions in preventing new type 2 diabetes in Asian populations

The aim of this study was to review current evidence on interventional studies aimed at the prevention of type 2 diabetes in Asian population with lifestyle interventions. Prevalence of type 2 diabetes sharply increased in most Asian countries during the last decades. This issue has now also relevant implication for Europe where different surveys are also consistently revealing an higher prevalence of type 2 diabetes and other and major CVD risk factors among subjects originating from Asian Countries than in the native population. Nutrition and lifestyle transition seem to play a role in disclosing the predisposition for the development of type 2 diabetes and great interest is now shown toward the possibility to intervene with lifestyle intervention on at risk populations. A meta-analysis of Randomized Controlled Trials showed that lifestyle interventions are highly effective also in the Asian population. All studies were, however, conducted with an individual approach based on the identification of high-risk individuals. When ethnic minority groups have to be addressed, an approach directed to the community rather than to the individual might, however, be more effective. This review reinforces the importance for policy-makers to consider the involvement of the whole community of minority immigrant groups with lifestyle intervention programs.

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.

Prevalence and determinants of diabetes and prediabetes among Vietnamese adults

AIMS

We estimated the prevalence of diabetes and prediabetes among Vietnamese adults, and quantitatively evaluated association with known risk factors.

METHODS

Subjects were 5602 men and 10,680 women in North Vietnam aged 30-69 years participating in community diabetes screening programs during 2011-2013. We calculated standardized prevalence rates and demographic projections for 2035, and used multinomial regression analysis to examine the associations of multiple risk factors with diabetes and prediabetes.

RESULTS

The age-, sex- and area of residence-standardized prevalence of diabetes was 6.0% and of prediabetes was 13.5%, with higher prevalence among men than women. Population aging is projected to raise the prevalence of diabetes to 7.0% and of prediabetes to 15.7% by 2035. Older age, obesity, large waist-to-hip ratio and hypertension were each associated with higher prevalence of diabetes, whereas the opposite direction of association was observed for underweight and minority ethnicity. In addition, diabetes was positively associated with family history of diabetes in women, but inversely related to physically heavy work among men.

CONCLUSIONS

One in 17 and one in 7 adults had diabetes and prediabetes, respectively, in Vietnam. Urbanization, population aging, increased adiposity, hypertension and sedentary work are associated with the increasing prevalence of diabetes.

Sitting Time, Fidgeting, and All-Cause Mortality in the UK Women's Cohort Study

INTRODUCTION

Sedentary behaviors (including sitting) may increase mortality risk independently of physical activity level. Little is known about how fidgeting behaviors might modify the association.

METHODS

Data were from the United Kingdom (UK) Women's Cohort Study. In 1999-2002, a total of 12,778 women (aged 37-78 years) provided data on average daily sitting time, overall fidgeting (irrespective of posture), and a range of relevant covariates including physical activity, diet, smoking status, and alcohol consumption. Participants were followed for mortality over a mean of 12 years. Proportional hazards Cox regression models estimated the relative risk of mortality in high (versus low) and medium (versus low) sitting time groups.

RESULTS

Fidgeting modified the risk associated with sitting time (p=0.04 for interaction), leading us to separate groups for analysis. Adjusting for covariates, sitting for ≥7 hours/day (versus <5 hours/day) was associated with 30% increased all-cause mortality risk (hazard ratio [HR]=1.30, 95% CI=1.02, 1.66) only among women in the low fidgeting group. Among women in the high fidgeting group, sitting for 5-6 hours/day (versus <5 hours/day) was associated with decreased mortality risk (HR=0.63, 95% CI=0.43, 0.91), adjusting for a range of covariates. There was no increased mortality risk from longer sitting time in the middle and high fidgeting groups.

CONCLUSIONS

Fidgeting may reduce the risk of all-cause mortality associated with excessive sitting time. More detailed and better-validated measures of fidgeting should be identified in other studies to replicate these findings and identity mechanisms, particularly measures that distinguish fidgeting in a seated from standing posture.

Pediatric obesity prevention: From naïve examination of energy imbalance towards strategies that influence the competition for nutrient resources among tissues

Current pediatric obesity interventions have collectively yielded relatively unsuccessful results. In this Field of Vision, we present plausible physiologic underpinnings fostering ineffectiveness of conventional strategies grounded in requisite induction of negative energy imbalance. Moreover, such recommendations exacerbate the underlying metabolic dysfunction by further limiting metabolic fuel availability, lowering energy expenditure, and increasing hunger (recapitulating the starvation response amid apparent nutritional adequacy) which precede and promote obesity during growth and development. The qualitative aspects of musculoskeletal system (i.e., endocrine response, muscle functional capacity) are likely to improve metabolic function and increase nutrient delivery and utilization. An intricate and complex system including multiple feedback mechanisms operates to homeostatically regulate energy balance and support optimal body composition trajectories and metabolic health, during growth and development. Thus, ignoring the interdependencies of regulatory growth processes initiates a nuanced understanding of energy regulation and thus misguided attempts at preventive strategies. Importantly, these gains are not dependent upon weight-loss, rather we suggest can be achieved through resistance training. Collectively, optimizing musculoskeletal health via resistance training elicits augmentation of competitive capacity across systems. Further, substantial gains can be achieved in skeletal muscle mass, strength, and functional capacity through resistance training in a relatively short period of time.

Health behavior change following a diagnosis of ductal carcinoma in situ: An opportunity to improve health outcomes

Ductal carcinoma in situ (DCIS) is a non-invasive breast cancer that comprises approximately 20% of new breast cancer diagnoses. DCIS is predominantly detected by screening mammography prior to the development of any clinical symptoms. Prognosis following a DCIS diagnosis is excellent, due to both the availability of effective treatments and the frequently benign nature of the disease. However, a DCIS diagnosis and its treatment have psychological and physical impacts that often lead to adverse changes in health-related behaviors, including changes in physical activity, body weight, alcohol intake, and smoking, which may represent a greater threat to the woman's overall health than the DCIS itself. Depending on age at diagnosis, women diagnosed with DCIS are 3-13 times more likely to die from non-breast cancer related causes, such as cardiovascular disease, than from breast cancer. Thus, the maintenance and improvement of healthy behaviors that influence a variety of outcomes after diagnosis may warrant increased attention during DCIS management. This may also represent an important opportunity to promote the adoption of healthy behaviors, given that DCIS carries the psychological impact of a cancer diagnosis but also a favorable prognosis. Particular focus is needed to address these issues in vulnerable patient subgroups with pre-existing higher rates of unhealthy behaviors and demonstrated health disparities.