Impact of sedentary behavior on large artery structure and function in children and adolescents: a systematic review

Accumulating Sedentary Time and Physical Activity From Childhood to Adolescence and Cardiac Function in Adolescence

BACKGROUND

Increased physical activity (PA) may mitigate the negative cardiovascular health effects of sedentary behavior in adolescents. However, the relationship of PA and sedentary time from childhood with cardiac function in adolescence remains underexplored. Therefore, we investigated the associations of cumulative sedentary time and PA from childhood to adolescence with cardiac function in adolescence.

METHODS AND RESULTS

Participants were 153 adolescents (69 girls) who were aged 6 to 8 years at baseline, 8 to 10 years at 2-year follow-up, and 15 to 17 years at 8-year follow-up. Cumulative sedentary time and PA exposure between baseline and 2-year follow-up and between baseline and 8-year follow-up were measured using a combined accelerometer and heart rate monitor. Cardiac function was assessed using impedance cardiography at 8-year follow-up. The data were analyzed using linear regression analyses adjusted for age and sex. Cumulative moderate to vigorous PA (standardized regression coefficient [β]=-0.323 [95% CI, -0.527 to -0.119]) and vigorous PA (β=-0.295 [95% CI, -0.508 to -0.083]) from baseline to 8-year follow-up were inversely associated with cardiac work at 8-year follow-up. Conversely, cumulative sedentary time had a positive association (β=0.245 [95% CI, 0.092-0.398]). Cumulative vigorous PA from baseline to 8-year follow-up was inversely associated with cardiac work index at 8-year follow-up (β=-0.218 [95% CI, -0.436 to 0.000]).

CONCLUSIONS

Higher levels of sedentary time and lower levels of PA during childhood were associated with higher cardiac work in adolescence, highlighting the importance of increasing PA and reducing sedentary time from childhood.

Clusters of lifestyle behaviors associated with atherosclerosis risk factors in children and adolescents with congenital heart disease: Floripa CHild Study

Secondary cardiovascular disease is the main cause of mortality in congenital heart disease (CHD) patients. The cardiovascular risk could be widely prevented with adherence to a healthy lifestyle; however, clusters of lifestyle behaviors related to atherosclerosis risk factors in children and adolescents with CHD remain unclear. We aimed to describe the clusters of lifestyle behaviors of children and adolescents with CHD and to evaluate their association with atherosclerosis risk factors. We conducted a cross-sectional study on 227 children and adolescents with CHD (median age:10.02 [IQR:7.08-13.02] years). Dietary intake, physical activity (PA), and sedentary behavior (SB) were evaluated. Clusters of lifestyle behaviors were determined using a two-step cluster analysis. Atherosclerosis risk factors evaluated include body fat mass, central obesity, blood pressure, lipid parameters, glucose, C-reactive protein, and carotid intima-media thickness (cIMT). Multiple logistic regressions were used. The "unhealthy: high SB + low PA" cluster was associated with elevated body fat mass, central obesity, and elevated cIMT. Furthermore, the "unhealthy: low PA + unhealthy eating habits" cluster was associated with elevated body fat mass, central obesity, and elevated glucose. The unhealthier lifestyle behavior clusters were associated with atherosclerosis risk factors in children and adolescents with CHD. Multidisciplinary strategies to promote healthy behaviors are needed to prevent cardiovascular disease in later life.

Sex differences in rat renal arterial responses following exercise training

During aerobic exercise, hemodynamic alterations occure; while blood flow in skeletal muscle arteries increases, it decreases in visceral vessels due to mesenterial vasoconstriction. However, maintaining renal blood flow during intensive sport is also a priority. Our aim was to investigate the changes of vascular reactivity and histology of isolated renal artery of male and female rats in response to swim-training. Wistar rats were distributed into four groups: male sedentary (MSed), male trained (MTr), female sedentary (FSed), and female trained (FTr). Trained animals underwent a 12-week-long intensive swimming program. Vascular function of isolated renal artery segments was examined by wire myography. Phenylephrine-induced contraction was lower in FSed compared to MSed animals, and it was decreased by training in male but not in female animals. Inhibition of cyclooxygenases by indomethacin reduced contraction in both sedentary groups, and in MTr but not in FTr animals. Inhibition of nitric oxide production increased contraction in both trained groups. Acetylcholine induced relaxation was similar in all experimental groups showing predominant NO-dependency. Elastin and smooth muscle cell actin density was reduced in female rats after aerobic training. This study shows that, as a result of 12-weeks-long training, there are sex differences in renal arterial responses following exercise training. Swimming moderates renal artery vasoconstriction in male animals, while it depresses elastic fiber and smooth muscle actin density in females.

The recommended amount of physical activity, sedentary behavior, and sleep duration for healthy Saudis: A joint consensus statement of the Saudi Public Health Authority

BACKGROUND:

The goal of the 24-h Movement Practice Guidelines for Saudi Arabia is to provide policymakers, health-care providers, researchers, sports professionals, and members of the public with recommendations on the duration of time they should spend engaged in physical activity, sedentary behavior, and sleep throughout all age groups.

METHODS:

A modified RAND appropriateness method and the “GRADE-ADOLOPMENT” approach of guideline recommendations were used by a guideline development panel to develop the present recommendations.

RESULTS:

The recommendations were based on the integrated needs of the following age groups: children (0–2 years), preschoolers (3–5 years), children and adolescents (6–17 years), adults (18–64 years), and older adults (≥65 years). The guidelines also include special considerations for sleep duration in the Saudi culture, such as dawn prayer and Ramadan.

CONCLUSIONS:

Several research gaps in physical activity, sedentary behavior, and sleep were identified and highlighted by the guideline development panel for potential future research.

Vascular Ageing in Youth: A Call to Action

Extensive evidence shows that risk factors for cardiovascular disease (CVD) begin to develop early in life. Childhood obesity and elevated blood pressure (BP) have become overwhelmingly challenging, with 57% of today's children predicted to be obese by the age of 35 years, and global rates of hypertension in children and adolescents increasing by 75% from 2000 to 2015. Thus, there is an urgent need for tools that can assess early CVD risk in youth, which may lead to better risk stratification, preventative intervention, and personalised medicine. Vascular ageing (the deterioration in vascular structure and function) is a pivotal progenitor of health degeneration associated with elevated BP. Exposure to adverse environmental and genetic factors from fetal life promotes the development and accumulation of subclinical vascular changes that direct an individual towards a trajectory of early vascular ageing (EVA)-an independent predictor of target organ damage in the heart, brain, and kidneys. Therefore, characterising vascular ageing from youth may provide a window into cardiovascular risk later in life. However, vascular ageing measurements only have value when techniques are accurate/validated and when reliable thresholds are available for defining normal ranges and ranges that signal increased risk of disease. The aim of this paper is to summarise current evidence on the importance of vascular ageing assessment in youth and the impact of interventions to prevent or delay EVA, to highlight the need for standardisation and validation of measurement techniques in children and adolescents, and the importance of establishing reference values for vascular ageing measures in this population.

Mind-Body Physical Activity Interventions and Stress-Related Physiological Markers in Educational Settings: A Systematic Review and Meta-Analysis

Mind–Body Physical Activity (MBPA) in educational settings is one possible preventive strategy for ameliorating stress-related physiological health parameters. The objectives of this study were to conduct a systematic review of the literature with meta-analyses on the effects of MBPA on stress-related physiological health markers in primary, secondary, and higher education students. In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, the search for peer-reviewed articles published in English was conducted in PubMed, EBSCOhost, PsychInfo, Scopus, and Cochrane Library databases. Criteria for inclusion consisted of empirical studies targeting the student population (primary, secondary, higher education), studies examining the effectiveness of an MBPA intervention, studies including a control or comparison group (pre-test/post-test studies excluded), studies targeting physiological marker outcomes such as heart rate, blood glucose, cortisol, and blood pressure, and finally, studies examining interventions implemented within educational settings. Twenty-six interventions were eligible for the review and quantitative synthesis, which comprised a total of 1625 participants, with 783 students serving within the control/comparison group. There were statistically significant and large pooled effects for MBPA effectiveness for lowering heart rate (Hedges’ g = −1.71, 95% Confidence Interval (CI): −2.43, −0.98), cortisol (Hedges’ g = −1.32, 95% CI: −2.50, −0.16), and systolic and diastolic blood pressure (Hedges’ g = −1.04, 95% CI: −1.53, −0.58). These effects tended to be stronger in older students compared to younger students. Most analyses were characterized as having high heterogeneity and only 10 of the 26 studies were characterized as good quality (38.4%). MBPA interventions may have a positive impact on specific physiological health markers in students, especially in students within higher education. However, higher-quality research is needed in this area.