Should we target increased physical activity or less sedentary behavior in the battle against cardiovascular disease risk development?

Accelerometer-Measured Sedentary Behavior and Risk of Future Cardiovascular Disease

BACKGROUND

Beyond serving as a marker for insufficient physical activity, sedentary behavior may directly affect future cardiovascular (CV) disease risk.

OBJECTIVES

This study sought to examine associations between accelerometer-measured sedentary behavior with risk of specific CV outcomes, including potential relations with moderate to vigorous physical activity (MVPA).

METHODS

Among participants of the UK Biobank prospective cohort study, we fit Cox models adjusted for demographic and lifestyle factors to assess associations between accelerometer-measured daily sedentary time with incident atrial fibrillation (AF), myocardial infarction (MI), heart failure (HF), and CV mortality. We assessed the potential effect of MVPA on associations between sedentary time and CV disease by including MVPA as an adjustment variable, as well as performing subgroup analyses stratified at the guideline-recommended MVPA threshold (ie, ≥150 min/wk). We then performed compositional analyses to estimate the effects of reallocating sedentary time to other activities.

RESULTS

Among 89,530 individuals (age 62 ± 8 years, 56.4% women) undergoing 1 week of accelerometry, median sedentary time was 9.4 h/d (Q1-Q3: 8.2-10.6). In multivariable models, using the second quartile (8.2-9.4 h/d) as a referent, sedentary time in the top quartile (>10.6 h/d) was associated with greater risks of HF (HR: 1.45; 95% CI: 1.28-1.65) and CV mortality (HR: 1.62; 95% CI: 1.34-1.96), with an inflection of risk at 10.6 h/d. Higher sedentary time was also associated with greater risks of incident AF (HR: 1.11; 95% CI: 1.01-1.21) and MI (HR: 1.15; 95% CI: 1.00-1.32), with an approximately linear relation. Associations with HF and CV mortality persisted among individuals meeting guideline-recommended MVPA levels. Among individuals with >10.6 h/d of sedentary time, reallocating sedentary behavior to other activities substantially reduced the excess CV risk conferred by sedentary behavior (eg, 30-minute decrease in sedentary time for HF: HR: 0.93; 95% CI: 0.90-0.96), even among individuals meeting guideline-recommended MVPA (HR: 0.93; 95% CI: 0.87-0.99).

CONCLUSIONS

Sedentary behavior is broadly associated with future adverse CV outcomes, with particularly prominent effects on HF and CV mortality, where risk inflected at approximately 10.6 h/d. Although guideline-adherent MVPA partially mitigates excess risk, optimizing sedentary behavior appears to be important even among physically active individuals.

Obesity Phenotypes, Lifestyle Medicine, and Population Health: Precision Needed Everywhere!

The worldwide prevalence of obesity is a key factor involved in the epidemic proportions reached by chronic societal diseases. A revolution in the study of obesity has been the development of imaging techniques for the measurement of its regional distribution. These imaging studies have consistently reported that individuals with an excess of visceral adipose tissue (VAT) were those characterized by the highest cardiometabolic risk. Excess VAT has also been found to be accompanied by ectopic fat deposition. It is proposed that subcutaneous versus visceral obesity can be considered as two extremes of a continuum of adiposity phenotypes with cardiometabolic risk ranging from low to high. The heterogeneity of obesity phenotypes represents a clinical challenge to the evaluation of cardiometabolic risk associated with a given body mass index (BMI). Simple tools can be used to better appreciate its heterogeneity. Measuring waist circumference is a relevant step to characterize fat distribution. Another important modulator of cardiometabolic risk is cardiorespiratory fitness. Individuals with a high level of cardiorespiratory fitness are characterized by a lower accumulation of VAT compared to those with poor fitness. Diet quality and level of physical activity are also key behaviors that substantially modulate cardiometabolic risk. It is proposed that it is no longer acceptable to assess the health risk of obesity using the BMI alone. In the context of personalized medicine, precision lifestyle medicine should be applied to the field of obesity, which should rather be referred to as 'obesities.'

Promotion of Cardiometabolic Health: A Personal Journey

PURPOSE OF REVIEW: Narrative review of the author's main contributions to the field of cardiovascular health spanning four decades, with a focus on findings related to 1- the pathophysiology of obesity, insulin resistance, type 2 diabetes and cardiovascular disease, and 2- the management/prevention of these conditions. Particular attention is given to the importance of regular physical activity. RECENT FINDINGS: Because behaviors and their physiological consequences are still not measured in clinical practice, it is proposed to systematically assess and target "lifestyle vital signs" (waist circumference, cardiorespiratory fitness, food-based diet quality and level of leisure-time physical activity) in primary care. However, cardiometabolic health of the population will not be substantially improved until our living and economic conditions are permissive to the adoption of healthy behaviors. Closing the gap between primary care and public health should be a priority to address the socioeconomic determinants of cardiometabolic health.

Can incidental physical activity offset the deleterious associations of sedentary behaviour with major adverse cardiovascular events?

AIMS

Incidental physical activity as part of daily living may offer feasibility advantages over traditional exercise. We examined the joint associations of incidental physical activity and sedentary behaviour with major adverse cardiovascular events (MACE) risk.

METHODS AND RESULTS

Analyses included 22 368 non-exercising adults from the UK Biobank accelerometry sub-study (median age [IQR]: 62.9 [11.6] years; 41.8% male). Physical activity and sedentary behaviour exposures were derived using a machine learning-based intensity and posture classification schema. We assessed the tertile-based joint associations of sedentary behaviour and the following: a) incidental vigorous (VPA), b) incidental moderate to vigorous (MVPA), c) vigorous intermittent lifestyle physical activity (VILPA; bouts lasting up to 1 min), and d) moderate to vigorous intermittent lifestyle physical activity (MV-ILPA; bouts lasting up to 3 min) with MACE risk. Over an 8.0-year median follow-up, 819 MACE events occurred. Compared to the highest physical activity and lowest sedentary time, high sedentary behaviour (>11.4 h/day) with low incidental VPA (<2.1 min/day) had an HR of 1.34 (95% CI: 0.98, 1.84) and low incidental MVPA (<21.8 min/day) had a 1.89 HR (95% CI: 1.42, 2.52) for MACE. Sedentary behaviour was not associated with MACE at medium and high levels of VPA or VILPA. Completing 4.1 min/day of VPA or VILPA may offset the MACE risk associated with high sedentary behaviour. Conversely, 31-65 min of incidental MVPA or 26-52 min of MV-ILPA per day largely attenuated the associations with MACE.

CONCLUSION

Brief intermittent bursts of vigorous incidental physical activity may offset cardiovascular risks from high sedentary behaviour.

LAY SUMMARY

Literature to date has examined the role of total or leisure time physical activity in mitigating the health risks associated with high sedentary behaviour. However, the vast majority of adults achieve their daily physical activity incidentally through day-to-day activities. In this study of 22 368 adults from the UK Biobank accelerometry sub-study, we provide the first investigation into whether a) incidental vigorous (VPA), b) incidental moderate to vigorous (MVPA), c) vigorous intermittent lifestyle physical activity (VILPA; bouts lasting up to 1 min), and d) moderate to vigorous intermittent lifestyle physical activity (MV-ILPA; bouts lasting up to 3 min) completed through normal daily living can offset the risk of major adverse cardiovascular events (MACE) associated with high sedentary behaviour (>11.4 h per day). We demonstrate that incidental VPA and MVPA may offset the MACE risk associated with high-sedentary behaviour even if accrued in brief bursts lasting <3 min. Completing 4.1 min/day of VPA or VILPA may offset the MACE risk associated with high sedentary behaviour.A daily duration of 31-65 min of incidental MVPA or 26-52 min of MV-ILPA per day largely attenuated the associations with MACE.

Knowledge, Attitudes, and Practice Regarding Physical Exercise in Type 2 Diabetic and Non-Diabetic Staff at a Tertiary Institution

Type 2 diabetes mellitus (T2DM) has become a global epidemic, where increasing urbanization encourages sedentary lifestyles. Persistent physical inactivity can lead to T2DM and increase the risk of T2DM in the general population. Therefore, the aim of this study was to explore the knowledge, attitudes, and practices (KAP) regarding exercise amongst T2DM and non-diabetic (ND) staff at a tertiary institution in KwaZulu Natal South Africa. A total of 166 responses were received: a total of 16 responses (9.6%) were T2DM, and 150 responses (90.0%) were non-diabetic (ND). The demographics included 66.3% females and 33.7% males who consented to taking part, 62.7% were black, 18.7% were Indian, 12% were white, 5.4% were colored, and 1.2% were other. A cross-sectional descriptive survey design, utilizing a modified validated online knowledge, attitudes, and practice questionnaire, was used to collect data. Descriptive statistics were used for the analysis: inferential statistics; the ordinal (1-5) Likert scale; t-tests; and chi-square tests. The level of statistical significance was set at p ≤ 0.05. No significant differences were found between the T2DM and ND groups except in their attitude towards exercise, which showed three items with significant differences. The ND group agreed significantly more than the T2DM group that they looked forward to exercising (p = 0.002), and even without company, they exercised regularly (p = 0.042). The T2DM group agreed significantly more with the statement that they had asked their doctor if there was medicine available to make them better without doing any exercise (p = 0.002). The overall KAP results of the current study found that both participants diagnosed with T2DM and those in the ND group know about exercise and have a good attitude toward exercise. However, both groups still have poor practice regarding physical activity.

Resistance exercise breaks during prolonged sitting augment the blood flow response to a subsequent oral glucose load in sedentary adults

Sitting-induced impairments in postprandial blood flow are an important link between sedentary behaviour and cardiometabolic disease risk. The objective of this work was to examine the effects of resistance exercise breaks (REB) performed every 30 min during an otherwise sedentary 3-h period on the vasodilatory response to a subsequent oral glucose load in sedentary adults. Twenty-four sedentary adults (27 ± 7 years, 16 females) completed two conditions. Fasting blood glucose, insulin, popliteal artery blood flow (PABF) and gastrocnemius perfusion were measured immediately before standardized breakfast consumption. After breakfast, the 3-h REB or uninterrupted (SIT) intervention period commenced. Participants sat at a workstation, and popliteal artery shear rate (PASR) was measured 60 and 120 min into this period. In the REB condition, participants performed a 3-min REB (3 × [20 s squats, 20 s high knees, 20 s calf raises]) every 30 min. Following the intervention period, baseline measurements were repeated. Participants then consumed a 75 g glucose beverage, and PABF and perfusion were measured every 30-60 min for the following 120 min. Relative to SIT, REB increased PASR at 60 min (+31.4 ± 9.2/s, P = 0.037) and 120 min (+37.4 ± 10.2/s, P = 0.019) into the intervention period. Insulin and glucose increased (P < 0.001) in response to glucose consumption, with no differences between conditions (P ≥ 0.299). In response to the glucose load, perfusion (1.57 vs. 1.11 mL/100 mL/min, P = 0.023) and PABF (+45.3 ± 11.8 mL/min, P = 0.001) were greater after REB versus SIT. Performing 3-min REB every 30 min during an otherwise sedentary 3-h period augmented leg blood flow responses to an oral glucose load. HIGHLIGHTS: What is the central question of this study? Can 3-min resistance exercise breaks (REB) performed during an otherwise sedentary 3-h period augment the vasodilatory response to a subsequent oral glucose load in sedentary adults? What is the main finding and its importance? Performing 3-min REB, which included squats, high knees, and calf raises, every 30 min augmented lower limb blood flow responses to a subsequent oral glucose load compared to 3 h of uninterrupted sitting in sedentary adults. Sitting-induced impairment in postprandial vasodilatory function has been identified as a link between sedentary behaviour and cardiometabolic disease. Thus, the current study presents a potentially effective strategy to offset this risk.

A 10-week implementation of the FIT FIRST FOR ALL school-based physical activity concept effectively improves cardiorespiratory fitness and body composition in 7-16-year-old schoolchildren

Introduction

The purpose of the present study was to investigate the impact of the FIT FIRST FOR ALL school-based physical activity program on health-related physical fitness in Faroese schoolchildren. The program aimed to add three weekly sessions of organized high-intensity physical activity to the standard weekly physical education sessions for all pupils across the entire school.

Methods

A non-randomized controlled design was used to evaluate the effects of the program. Two schools participated, including one intervention school (INT; n =179) and one control school (CON; n =181), with pupils aged 7-16 years (grades 1-9). The FIT FIRST FOR ALL program consisted of three weekly 40-minute sessions of age-adjusted high-intensity physical activity over 10 weeks for the INT school, while the CON school continued their normal school program. Pre- and post-intervention assessments included cardiorespiratory fitness (Yo-Yo IR1C test), agility (Arrowhead Agility test), postural balance (Stork Stand), standing long jump performance, body composition, blood pressure, and resting heart rate.

Results

A significant time × group effect (p < 0.001) was observed for cardiorespiratory fitness, which increased by 31% [23;39] in INT (p < 0.001) and remained unaltered in CON (7% [-2;16], p = 0.13). In addition, a time × group effect (p < 0.001) was observed for agility, which improved by 2.1% [1.0;3.2] in INT (p < 0.001) and regressed by 3.3% [2.3;4.4] in CON (p < 0.001). No significant between-group effects were found for standing long jump and balance. A time × group effect (p < 0.001) was observed for changes in total muscle mass, which increased by 1.4 kg [1.2;1.5] in INT (p < 0.001) and by 0.4 kg [0.3;0.6] in CON (p < 0.05). Furthermore, a time × group effect (p < 0.001) was observed for total fat percentage, which decreased by -2.3% [-2.8;-1.9] in INT (p < 0.001) and remained unchanged in CON (-0.3% [-0.7;0.1], p = 0.16). No significant time × group effects were found for blood pressure and resting heart rate.

Discussion

The FIT FIRST FOR ALL program significantly improved cardiorespiratory fitness and agility, and it led to favorable changes in body composition in the intervention school. These findings suggest that the program is highly effective in enhancing physical fitness and health status across all investigated age groups when implemented at a school-wide level.

Longitudinal description and prediction of physical inactivity among patients with borderline personality disorder and personality-disordered comparison subjects

BACKGROUND

The physical and psychological benefits of physical activity are well-known, and physical activity has been proven to be a helpful adjunct to psychotherapeutic treatment for many symptomatic disorders, including mood and anxiety disorders. The current study explores physical inactivity levels in patients with borderline personality disorder (BPD). The first aim of this study is to describe the 12-year course of physical inactivity in patients with BPD. The second aim is to examine predictors of physical inactivity, including adversity experiences, comorbid symptomatic (formerly axis I) disorders, medical disorders, and demographic factors.

METHODS

Two hundred and forty-five patients with BPD were interviewed seven times over 12-years of prospective follow-up as part of the McLean Study of Adult Development (MSAD). Patients were categorized as ever-recovered (i.e., patient had experienced a symptomatic and psychosocial recovery from BPD) or never-recovered. At each follow-up, patients reported physical activity levels (minutes of exercise per week) via a semi-structured interview- the Medical History and Services Utilization Interview (MHSUI). Data was collected from June 1992 to December 2018.

RESULTS

Never-recovered patients with BPD were significantly more inactive than their ever-recovered counterparts (p < 0.001). These rates of inactivity remained stable over time for both groups. Two significant multivariate predictors of inactivity were found: obesity (p = 0.003) and PTSD (p < 0.001).

CONCLUSIONS

Non-recovered BPD patients are more likely to be inactive than patients who have recovered. Both clinical and medical factors appear to contribute to inactivity levels in patients with BPD.

Acceptability of Performing Resistance Exercise Breaks in the Workplace to Break Up Prolonged Sedentary Time: A Randomized Control Trial in U.S. Office Workers and Students

We investigated the acceptability of bodyweight resistance exercise breaks (REB) to disrupt prolonged sedentary behavior in the workplace. Twenty-nine individuals completed a REB, where they performed 3-min REB 4, 8, and 16 times on days 1-2, 3-4, and 5 of the workweek, respectively, and a control condition (i.e., SIT). Productivity was assessed on days 1 and 5 each week. The acceptability of each REB frequency was assessed. When asked to complete 4, 8, and 16 REB, participants completed (mean values) 3.2, 6.2, and 9.2 REB/day, respectively. Moreover, 88%, 40%, and 9% of participants expressed that the 4-, 8-, and 16-REB frequencies were acceptable, respectively. Decision-making ability and concentration levels increased from day 1-5 of the REB week (p=0.048) but were stable during SIT. REB (4/day) are highly acceptable and could be a promising intervention strategy for reducing occupational sitting, thus decreasing sedentary-behavior-induced risk.

Clustering of health behaviors and their associations with cardiometabolic risk factors among adults at high risk for type 2 diabetes in India: A latent class analysis

BACKGROUND

We aimed to identify clusters of health behaviors and study their associations with cardiometabolic risk factors in adults at high risk for type 2 diabetes in India.

METHODS

Baseline data from the Kerala Diabetes Prevention Program (n = 1000; age 30-60 years) were used for this study. Information on physical activity (PA), sedentary behavior, fruit and vegetable intake, sleep, and alcohol and tobacco use was collected using questionnaires. Blood pressure, waist circumference, 2-h plasma glucose, high-density lipoprotein and low-density lipoprotein cholesterol, and triglycerides were measured using standardized protocols. Latent class analysis was used to identify clusters of health behaviors, and multilevel mixed-effects linear regression was employed to examine their associations with cardiometabolic risk factors.

RESULTS

Two classes were identified, with 87.4% of participants in class 1 and 12.6% in class 2. Participants in both classes had a high probability of not engaging in leisure-time PA (0.80 for class 1; 0.73 for class 2) and consuming <5 servings of fruit and vegetables per day (0.70 for class 1; 0.63 for class 2). However, participants in class 1 had a lower probability of sitting for >=3 h per day (0.26 vs 0.42), tobacco use (0.10 vs 0.75), and alcohol use (0.08 vs 1.00) compared to those in class 2. Class 1 had a significantly lower mean systolic blood pressure (β = -3.70 mm Hg, 95% confidence interval [CI] -7.05, -0.36), diastolic blood pressure (β = -2.45 mm Hg, 95% CI -4.74, -0.16), and triglycerides (β = -0.81 mg/dL, 95% CI -0.75, -0.89).

CONCLUSION

Implementing intervention strategies, tailored to cluster-specific health behaviors, is required for the effective prevention of cardiometabolic disorders among high-risk adults for type 2 diabetes.

All-cause mortality attributable to sitting time and physical inactivity in chilean adults

BACKGROUND

Evidence on all-cause mortality attributable to joint sitting time and physical inactivity is lacking. In this study, we estimated the proportion and number of deaths attributable to sitting time and physical inactivity in Chilean adults.

METHODS

A sample of 5834 adults aged 20-96 years from a 2016-2017 Chilean National Health Survey was included to describe the prevalence of 16 joint categories of sitting time and physical activity. Relative risks for the joint association of sitting time and physical inactivity were obtained from a meta-analysis of individual participant data. We retrieved the number of deaths in adults ≥ 20 years in 2019 from the Chilean Ministry of Health.

RESULTS

Participants with high sitting time (> 8 h/day) and low physical activity (< 2.5 MET-hour/week) were more likely to be women, 20-64 years, non-indigenous ethnicity, lived in the urban areas, had middle education level and monthly household income, and had public health insurance. Reducing sitting time and increasing physical activity to a theoretical minimum risk exposure level could prevent up to 11,470 deaths or 10.4% of all deaths. Increasing physical activity to >35.5 MET-hour/week and maintaining sitting time could prevent approximately 10,477 deaths or 9.5% of all deaths. Reducing sitting time to < 4 h/day and maintaining physical activity would not reduce the number of deaths (-3.4% or 38 deaths).

CONCLUSION

Reducing sitting time may be ancillary for preventing mortality. Therefore, increasing physical activity should be the primary focus of interventions and policies in Chile.

Substituting sedentary time with physical activity in youngest-old to oldest-old community-dwelling older adults: Associations with body composition

Introduction

Several studies have suggested that physical activity and sedentary behavior are strongly and independently associated with body composition and obesity. However, few studies have investigated whether substituting sedentary time with moderate-to-vigorous physical activity is associated with body composition in older adults, especially among those older than 75 years.

Methods

This study examined the associations between replacing sedentary time with physical activity and obesity indices in a sample of 199 community-dwelling older Taiwanese adults (52.3% women; 80.6 ± 7.0 years). Physical activity and sedentary behavior were measured using the triaxial accelerometer (GT3X+, ActiGraph). Body composition indices were computed through a bioelectrical impedance analysis of body fat percentage and appendicular skeletal muscle mass index. Waist circumference and body mass index were measured by trained personnel. Isotemporal substitution analyses estimated these associations after adjusting for sociodemographic characteristics and nutritional status.

Results

The study showed that substituting 30 min of sedentary behavior per day with moderate-to-vigorous physical activity was associated with lower body fat percentage (B = -1.408, 95% CI = -2.55, -0.264), body mass index (B = -0.681, 95% CI = -1.300, -0.061), and waist circumference (B = -2.301, 95% CI = -4.062, -0.539) after adjusting for covariates. Substituting 30 min of light physical activity per day with moderate-to-vigorous physical activity was associated with lower waist circumference (B = -2.230, 95% CI = -4.173, -0.287) after adjusting for covariates. Stratified analyses indicated that associations were stronger in youngest-old older adults, and in older adults with a normal nutritional status (vs. underweight status).

Discussion

These findings confirm the importance of reducing sedentary behavior and increasing moderate-to-vigorous physical activity among older adults to improve their physical health, as well as highlighting the importance of taking into account nutritional status and age group.

Systematic review of electronically delivered behavioral obesity prevention interventions targeting men

Globally, obesity persists at epidemic rates. Men are underrepresented within behavior-based obesity prevention research. As men prefer individualized, self-guided interventions, electronic delivery of treatment modalities has potential to reach this population. The purpose of this study was to systematically review primary, secondary, or tertiary behavioral obesity prevention interventions that used controlled designs; targeted men; and incorporated at least one electronically delivered treatment modality explicitly designed to elicit an intervention effect. Literature searches were delimited to peer-reviewed articles; published between 2000 and 2021; in the English language; and indexed in PsycINFO, CINHAL, MEDLINE, CENTRAL, and WOS electronic databases. Interventions satisfying inclusion criteria were critiqued for methodological quality using the Jadad Scale (0 = lowest quality; 10 = highest quality). Eleven studies satisfied the inclusion criteria (n = 1748; total participants) with five reporting group-by-time intervention effects on the primary variable targeted. Jadad scale quality assessment scores ranged from 5.00 to 9.00 with a mean of 7.72. Majority of the interventions applied a randomized control trial design (n = 10). Most interventions were theory based, with eight rooted in social cognitive theory. Behavior change strategies included self-monitoring (n = 10), personalized feedback (n = 8), health counseling (n = 8), and goal setting (n = 9). Community-level theories have the potential to guide future obesity prevention interventions targeting men.

Measurement of Physical Fitness and 24/7 Physical Activity, Standing, Sedentary Behavior, and Time in Bed in Working-Age Finns: Study Protocol for FINFIT 2021

Background: Population studies gathering measured data on fitness and physical behavior, covering physical activity, standing, sedentary behavior, and time in bed, are scarce. This article describes the protocol of the FINFIT 2021 study that measures fitness and physical behavior in a population-based sample of adults and analyzes their associations and dose–response relationships with several health indicators. Methods: The study comprises a stratified random sample of 20–69-year-old men and women (n = 16,500) from seven city-centered regions in Finland. Physical behavior is measured 24/7 by tri-axial accelerometry and analyzed with validated MAD-APE algorithms. Health and fitness examinations include fasting blood samples, measurements of blood pressure, anthropometry, and health-related fitness. Domains of health, functioning, well-being, and socio-demographics are assessed by a questionnaire. The data are being collected between September 2021 and February 2022. Discussion: The study provides population data on physical fitness and physical behavior 24/7. Physical behavior patterns by intensity and duration on an hour-by-hour basis will be provided. In the future, the baseline data will be assessed against prospective register-based data on incident diseases, healthcare utilization, sickness absence, premature retirement, and death. A similar study will be conducted every fourth year with a new random population sample.

Measuring Exercise-Induced Secreted Protein Acidic and Rich in Cysteine Expression as a Molecular Tool to Optimize Personalized Medicine

The numerous exercise benefits for health as well as applications for diseases has lead to exercise being prescribed in many pathological conditions. Secreted protein acidic and rich in cysteine (SPARC) gene expression is stimulated by exercise and SPARC has been suggested as a molecular mediator of exercise. Therefore, we suggest using this property for personalized medicine. This can be achieved by prescribing the exercise with a pattern (duration, intensity, etc.) that corresponds to the optimum SPARC/Sparc expression. We expect this approach to optimize the exercise therapy in both the preventive and curative contexts. In the research field, measuring exercise -dependent expression of Sparc would represent a molecular tool to further optimize the selection of exercise animal models as well.

Sit less and move more for cardiovascular health: emerging insights and opportunities

Sedentary behaviour - put simply, too much sitting, as a distinct concept from too little exercise - is a novel determinant of cardiovascular risk. This definition provides a perspective that is complementary to the well-understood detrimental effects of physical inactivity. Sitting occupies the majority of the daily waking hours in most adults and has become even more pervasive owing to the COVID-19 pandemic. The potential for a broad cardiovascular health benefit exists through an integrated approach that involves 'sitting less and moving more'. In this Review, we first consider observational and experimental evidence on the adverse effects of prolonged, uninterrupted sitting and the evidence identifying the possible mechanisms underlying the associated risk. We summarize the results of randomized controlled trials demonstrating the feasibility of changing sedentary behaviour. We also highlight evidence on the deleterious synergies between sedentary behaviour and physical inactivity as the underpinnings of our case for addressing them jointly in mitigating cardiovascular risk. This integrated approach should not only reduce the specific risks of too much sitting but also have a positive effect on the total amount of physical activity, with the potential to more broadly benefit the health of individuals living with or at risk of developing cardiovascular disease.

Skeletal Muscle Nrf2 Contributes to Exercise-Evoked Systemic Antioxidant Defense Via Extracellular Vesicular Communication

This review explores the hypothesis that the repetitive contraction-relaxation that occurs during chronic exercise activates skeletal myocyte nuclear factor erythroid-derived 2-like 2 (Nrf2) to upregulate antioxidant enzymes. These proteins are secreted into the circulation within extracellular vesicles and taken up by remote cells, thus providing remote organs with cytoprotection against subsequent oxidative stress.